From 479838ab281aa1e8c5b9d6a693c259552f4e2cfd Mon Sep 17 00:00:00 2001
From: Dakota Paasman <dpaasman00@gmail.com>
Date: Mon, 5 Feb 2024 10:12:12 -0500
Subject: [PATCH 1/9] write ottl key value func

---
 pkg/ottl/ottlfuncs/func_parse_key_value.go    | 100 +++++++
 .../ottlfuncs/func_parse_key_value_test.go    | 270 ++++++++++++++++++
 pkg/ottl/ottlfuncs/functions.go               |   1 +
 3 files changed, 371 insertions(+)
 create mode 100644 pkg/ottl/ottlfuncs/func_parse_key_value.go
 create mode 100644 pkg/ottl/ottlfuncs/func_parse_key_value_test.go

diff --git a/pkg/ottl/ottlfuncs/func_parse_key_value.go b/pkg/ottl/ottlfuncs/func_parse_key_value.go
new file mode 100644
index 000000000000..14aa09f1e472
--- /dev/null
+++ b/pkg/ottl/ottlfuncs/func_parse_key_value.go
@@ -0,0 +1,100 @@
+package ottlfuncs
+
+import (
+	"context"
+	"fmt"
+	"strings"
+
+	"github.com/open-telemetry/opentelemetry-collector-contrib/pkg/ottl"
+	"go.opentelemetry.io/collector/pdata/pcommon"
+)
+
+type ParseKeyValueArguments[K any] struct {
+	Target        ottl.StringGetter[K]
+	Delimiter     ottl.Optional[string]
+	PairDelimiter ottl.Optional[string]
+}
+
+func NewParseKeyValueFactory[K any]() ottl.Factory[K] {
+	return ottl.NewFactory("ParseKeyValue", &ParseKeyValueArguments[K]{}, createParseKeyValueFunction[K])
+}
+
+func createParseKeyValueFunction[K any](_ ottl.FunctionContext, oArgs ottl.Arguments) (ottl.ExprFunc[K], error) {
+	args, ok := oArgs.(*ParseKeyValueArguments[K])
+
+	if !ok {
+		return nil, fmt.Errorf("ParseKeyValueFactory args must be of type *ParseKeyValueArguments[K]")
+	}
+
+	return parseKeyValue[K](args.Target, args.Delimiter, args.PairDelimiter)
+}
+
+func parseKeyValue[K any](target ottl.StringGetter[K], d ottl.Optional[string], p ottl.Optional[string]) (ottl.ExprFunc[K], error) {
+	delimiter := "="
+	if !d.IsEmpty() {
+		delimiter = d.Get()
+	}
+
+	pair_delimiter := " "
+	if !p.IsEmpty() {
+		pair_delimiter = p.Get()
+		if pair_delimiter == delimiter {
+			return nil, fmt.Errorf("pair delimiter \"%s\" cannot be equal to delimiter \"%s\"", pair_delimiter, delimiter)
+		}
+	}
+
+	return func(ctx context.Context, tCtx K) (any, error) {
+		source, err := target.Get(ctx, tCtx)
+		if err != nil {
+			return nil, err
+		}
+
+		if source == "" {
+			return nil, fmt.Errorf("cannot parse from empty target")
+		}
+
+		parsed := make(map[string]any)
+		for _, s := range splitString(source, pair_delimiter) {
+			pair := strings.SplitN(s, delimiter, 2)
+			if len(pair) != 2 {
+				return nil, fmt.Errorf("cannot split '%s' into 2 items, got %d", s, len(pair))
+			}
+			key := strings.TrimSpace(strings.Trim(pair[0], "\"'"))
+			value := strings.TrimSpace(strings.Trim(pair[1], "\"'"))
+			parsed[key] = value
+		}
+
+		result := pcommon.NewMap()
+		err = result.FromRaw(parsed)
+		return result, err
+	}, nil
+}
+
+func splitString(input, delimiter string) []string {
+	var result []string
+	inQuotes := false
+	currentPair := ""
+	delimiterLength := len(delimiter)
+
+	for i := 0; i < len(input); i++ {
+		if i+delimiterLength <= len(input) && input[i:i+delimiterLength] == delimiter && !inQuotes {
+			if currentPair == "" {
+				continue
+			}
+			result = append(result, currentPair)
+			currentPair = ""
+			i += delimiterLength - 1
+		} else if input[i] == '"' || input[i] == '\'' {
+			inQuotes = !inQuotes
+			currentPair += string(input[i])
+		} else {
+			currentPair += string(input[i])
+		}
+	}
+
+	if currentPair != "" {
+		result = append(result, currentPair)
+	}
+
+	return result
+}
diff --git a/pkg/ottl/ottlfuncs/func_parse_key_value_test.go b/pkg/ottl/ottlfuncs/func_parse_key_value_test.go
new file mode 100644
index 000000000000..e7d4d12d4da1
--- /dev/null
+++ b/pkg/ottl/ottlfuncs/func_parse_key_value_test.go
@@ -0,0 +1,270 @@
+package ottlfuncs
+
+import (
+	"context"
+	"testing"
+
+	"github.com/open-telemetry/opentelemetry-collector-contrib/pkg/ottl"
+	"github.com/stretchr/testify/assert"
+	"go.opentelemetry.io/collector/pdata/pcommon"
+)
+
+func Test_parseKeyValue(t *testing.T) {
+	tests := []struct {
+		name           string
+		target         ottl.StringGetter[any]
+		delimiter      ottl.Optional[string]
+		pair_delimiter ottl.Optional[string]
+		expected       map[string]any
+	}{
+		{
+			name: "simple",
+			target: ottl.StandardStringGetter[any]{
+				Getter: func(ctx context.Context, tCtx any) (any, error) {
+					return "name=ottl func=key_value", nil
+				},
+			},
+			delimiter:      ottl.Optional[string]{},
+			pair_delimiter: ottl.Optional[string]{},
+			expected: map[string]any{
+				"name": "ottl",
+				"func": "key_value",
+			},
+		},
+		{
+			name: "large",
+			target: ottl.StandardStringGetter[any]{
+				Getter: func(ctx context.Context, tCtx any) (any, error) {
+					return `name=ottl age=1 job="software engineering" location="grand rapids michigan" src="10.3.3.76" dst=172.217.0.10 protocol=udp sport=57112 port=443 translated_src_ip=96.63.176.3 translated_port=57112`, nil
+				},
+			},
+			delimiter:      ottl.Optional[string]{},
+			pair_delimiter: ottl.Optional[string]{},
+			expected: map[string]any{
+				"age":               "1",
+				"port":              "443",
+				"dst":               "172.217.0.10",
+				"job":               "software engineering",
+				"location":          "grand rapids michigan",
+				"name":              "ottl",
+				"protocol":          "udp",
+				"sport":             "57112",
+				"src":               "10.3.3.76",
+				"translated_port":   "57112",
+				"translated_src_ip": "96.63.176.3",
+			},
+		},
+		{
+			name: "double quotes",
+			target: ottl.StandardStringGetter[any]{
+				Getter: func(ctx context.Context, tCtx any) (any, error) {
+					return `requestClientApplication="Mozilla/5.0 (Windows NT 6.1; WOW64; rv:40.0) Gecko/20100101 Firefox/40.0"`, nil
+				},
+			},
+			delimiter:      ottl.Optional[string]{},
+			pair_delimiter: ottl.Optional[string]{},
+			expected: map[string]any{
+				"requestClientApplication": "Mozilla/5.0 (Windows NT 6.1; WOW64; rv:40.0) Gecko/20100101 Firefox/40.0",
+			},
+		},
+		{
+			name: "single quotes",
+			target: ottl.StandardStringGetter[any]{
+				Getter: func(ctx context.Context, tCtx any) (any, error) {
+					return "requestClientApplication='Mozilla/5.0 (Windows NT 6.1; WOW64; rv:40.0) Gecko/20100101 Firefox/40.0'", nil
+				},
+			},
+			delimiter:      ottl.Optional[string]{},
+			pair_delimiter: ottl.Optional[string]{},
+			expected: map[string]any{
+				"requestClientApplication": "Mozilla/5.0 (Windows NT 6.1; WOW64; rv:40.0) Gecko/20100101 Firefox/40.0",
+			},
+		},
+		{
+			name: "double quotes strip leading & trailing spaces",
+			target: ottl.StandardStringGetter[any]{
+				Getter: func(ctx context.Context, tCtx any) (any, error) {
+					return `name="   ottl " func="  key_ value"`, nil
+				},
+			},
+			delimiter:      ottl.Optional[string]{},
+			pair_delimiter: ottl.Optional[string]{},
+			expected: map[string]any{
+				"name": "ottl",
+				"func": "key_ value",
+			},
+		},
+		{
+			name: "! delimiter && whitespace pair delimiter",
+			target: ottl.StandardStringGetter[any]{
+				Getter: func(ctx context.Context, tCtx any) (any, error) {
+					return "   name!ottl     func!key_value hello!world  ", nil
+				},
+			},
+			delimiter:      ottl.NewTestingOptional[string]("!"),
+			pair_delimiter: ottl.Optional[string]{},
+			expected: map[string]any{
+				"name":  "ottl",
+				"func":  "key_value",
+				"hello": "world",
+			},
+		},
+		{
+			name: "!! delimiter && whitespace pair delimiter with newlines",
+			target: ottl.StandardStringGetter[any]{
+				Getter: func(ctx context.Context, tCtx any) (any, error) {
+					return `   
+name!!ottl     
+func!!key_value                      hello!!world  `, nil
+				},
+			},
+			delimiter:      ottl.NewTestingOptional[string]("!!"),
+			pair_delimiter: ottl.Optional[string]{},
+			expected: map[string]any{
+				"name":  "ottl",
+				"func":  "key_value",
+				"hello": "world",
+			},
+		},
+		{
+			name: "!! delimiter && newline pair delimiter",
+			target: ottl.StandardStringGetter[any]{
+				Getter: func(ctx context.Context, tCtx any) (any, error) {
+					return `name!!ottl     
+func!!      key_value another!!pair
+hello!!world  `, nil
+				},
+			},
+			delimiter:      ottl.NewTestingOptional[string]("!!"),
+			pair_delimiter: ottl.NewTestingOptional[string]("\n"),
+			expected: map[string]any{
+				"name":  "ottl",
+				"func":  "key_value another!!pair",
+				"hello": "world",
+			},
+		},
+		{
+			name: "quoted value contains delimiter and pair delimiter",
+			target: ottl.StandardStringGetter[any]{
+				Getter: func(ctx context.Context, tCtx any) (any, error) {
+					return `name="ottl="_func="=key_value"`, nil
+				},
+			},
+			delimiter:      ottl.Optional[string]{},
+			pair_delimiter: ottl.NewTestingOptional("_"),
+			expected: map[string]any{
+				"name": "ottl=",
+				"func": "=key_value",
+			},
+		},
+		{
+			name: "complicated delimiters",
+			target: ottl.StandardStringGetter[any]{
+				Getter: func(ctx context.Context, tCtx any) (any, error) {
+					return `k1@*v1_!_k2@**v2_!__k3@@*v3__`, nil
+				},
+			},
+			delimiter:      ottl.NewTestingOptional("@*"),
+			pair_delimiter: ottl.NewTestingOptional("_!_"),
+			expected: map[string]any{
+				"k1":   "v1",
+				"k2":   "*v2",
+				"_k3@": "v3__",
+			},
+		},
+		{
+			name: "leading and trailing pair delimiter",
+			target: ottl.StandardStringGetter[any]{
+				Getter: func(ctx context.Context, tCtx any) (any, error) {
+					return "   k1=v1   k2==v2       k3=v3= ", nil
+				},
+			},
+			delimiter:      ottl.Optional[string]{},
+			pair_delimiter: ottl.Optional[string]{},
+			expected: map[string]any{
+				"k1": "v1",
+				"k2": "=v2",
+				"k3": "v3=",
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(t.Name(), func(t *testing.T) {
+			exprFunc, err := parseKeyValue[any](tt.target, tt.delimiter, tt.pair_delimiter)
+			assert.NoError(t, err)
+
+			result, err := exprFunc(context.Background(), nil)
+			assert.NoError(t, err)
+
+			actual, ok := result.(pcommon.Map)
+			assert.True(t, ok)
+
+			expected := pcommon.NewMap()
+			assert.NoError(t, expected.FromRaw(tt.expected))
+
+			assert.Equal(t, expected.Len(), actual.Len())
+			expected.Range(func(k string, v pcommon.Value) bool {
+				ev, _ := expected.Get(k)
+				av, ok := actual.Get(k)
+				assert.True(t, ok)
+				assert.Equal(t, ev, av)
+				return true
+			})
+		})
+	}
+}
+
+func Test_parseKeyValue_equal_delimiters(t *testing.T) {
+	target := ottl.StandardStringGetter[any]{
+		Getter: func(ctx context.Context, tCtx any) (any, error) {
+			return "", nil
+		},
+	}
+	delimiter := ottl.NewTestingOptional[string]("=")
+	pair_delimiter := ottl.NewTestingOptional[string]("=")
+	_, err := parseKeyValue[any](target, delimiter, pair_delimiter)
+	assert.Error(t, err)
+}
+
+func Test_parseKeyValue_bad_target(t *testing.T) {
+	target := ottl.StandardStringGetter[any]{
+		Getter: func(ctx context.Context, tCtx any) (any, error) {
+			return 1, nil
+		},
+	}
+	delimiter := ottl.NewTestingOptional[string]("=")
+	pair_delimiter := ottl.NewTestingOptional[string]("!")
+	exprFunc, err := parseKeyValue[any](target, delimiter, pair_delimiter)
+	assert.NoError(t, err)
+	_, err = exprFunc(context.Background(), nil)
+	assert.Error(t, err)
+}
+
+func Test_parseKeyValue_empty_target(t *testing.T) {
+	target := ottl.StandardStringGetter[any]{
+		Getter: func(ctx context.Context, tCtx any) (any, error) {
+			return "", nil
+		},
+	}
+	delimiter := ottl.NewTestingOptional[string]("=")
+	pair_delimiter := ottl.NewTestingOptional[string]("!")
+	exprFunc, err := parseKeyValue[any](target, delimiter, pair_delimiter)
+	assert.NoError(t, err)
+	_, err = exprFunc(context.Background(), nil)
+	assert.Error(t, err)
+}
+
+func Test_parseKeyValue_bad_split(t *testing.T) {
+	target := ottl.StandardStringGetter[any]{
+		Getter: func(ctx context.Context, tCtx any) (any, error) {
+			return "name=ottl!hello_world", nil
+		},
+	}
+	delimiter := ottl.NewTestingOptional[string]("=")
+	pair_delimiter := ottl.NewTestingOptional[string]("!")
+	exprFunc, err := parseKeyValue[any](target, delimiter, pair_delimiter)
+	assert.NoError(t, err)
+	_, err = exprFunc(context.Background(), nil)
+	assert.Error(t, err)
+}
diff --git a/pkg/ottl/ottlfuncs/functions.go b/pkg/ottl/ottlfuncs/functions.go
index 3e498549a58c..657b88280367 100644
--- a/pkg/ottl/ottlfuncs/functions.go
+++ b/pkg/ottl/ottlfuncs/functions.go
@@ -57,6 +57,7 @@ func converters[K any]() []ottl.Factory[K] {
 		NewNanosecondsFactory[K](),
 		NewNowFactory[K](),
 		NewParseJSONFactory[K](),
+		NewParseKeyValueFactory[K](),
 		NewSecondsFactory[K](),
 		NewSHA1Factory[K](),
 		NewSHA256Factory[K](),

From e36dbd7cdcf97d9552a1b24ccc6de7eafffa28e7 Mon Sep 17 00:00:00 2001
From: Dakota Paasman <dpaasman00@gmail.com>
Date: Mon, 5 Feb 2024 11:01:04 -0500
Subject: [PATCH 2/9] add e2e tests, documentation, and changelog entry

---
 ...pkg-ottl-add-parse-key-value-function.yaml | 27 +++++++++++++++++++
 pkg/ottl/e2e/e2e_test.go                      | 24 +++++++++++++++++
 pkg/ottl/ottlfuncs/README.md                  | 21 +++++++++++++++
 3 files changed, 72 insertions(+)
 create mode 100644 .chloggen/pkg-ottl-add-parse-key-value-function.yaml

diff --git a/.chloggen/pkg-ottl-add-parse-key-value-function.yaml b/.chloggen/pkg-ottl-add-parse-key-value-function.yaml
new file mode 100644
index 000000000000..c6a5b206dcde
--- /dev/null
+++ b/.chloggen/pkg-ottl-add-parse-key-value-function.yaml
@@ -0,0 +1,27 @@
+# Use this changelog template to create an entry for release notes.
+
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: enhancement
+
+# The name of the component, or a single word describing the area of concern, (e.g. filelogreceiver)
+component: pkg/ottl
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: Add `ParseKeyValue` function for parsing key value pairs from a target string
+
+# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
+issues: [30998]
+
+# (Optional) One or more lines of additional information to render under the primary note.
+# These lines will be padded with 2 spaces and then inserted directly into the document.
+# Use pipe (|) for multiline entries.
+subtext:
+
+# If your change doesn't affect end users or the exported elements of any package,
+# you should instead start your pull request title with [chore] or use the "Skip Changelog" label.
+# Optional: The change log or logs in which this entry should be included.
+# e.g. '[user]' or '[user, api]'
+# Include 'user' if the change is relevant to end users.
+# Include 'api' if there is a change to a library API.
+# Default: '[user]'
+change_logs: []
diff --git a/pkg/ottl/e2e/e2e_test.go b/pkg/ottl/e2e/e2e_test.go
index 57bbedb708fe..4235d506d568 100644
--- a/pkg/ottl/e2e/e2e_test.go
+++ b/pkg/ottl/e2e/e2e_test.go
@@ -437,6 +437,30 @@ func Test_e2e_converters(t *testing.T) {
 				m.PutDouble("id", 1)
 			},
 		},
+		{
+			statement: `set(attributes["test"], ParseKeyValue("k1=v1 k2=v2"))`,
+			want: func(tCtx ottllog.TransformContext) {
+				m := tCtx.GetLogRecord().Attributes().PutEmptyMap("test")
+				m.PutStr("k1", "v1")
+				m.PutStr("k2", "v2")
+			},
+		},
+		{
+			statement: `set(attributes["test"], ParseKeyValue("k1!v1_k2!v2", "!", "_"))`,
+			want: func(tCtx ottllog.TransformContext) {
+				m := tCtx.GetLogRecord().Attributes().PutEmptyMap("test")
+				m.PutStr("k1", "v1")
+				m.PutStr("k2", "v2")
+			},
+		},
+		{
+			statement: `set(attributes["test"], ParseKeyValue("k1!v1_k2!\"v2__!__v2\"", "!", "_"))`,
+			want: func(tCtx ottllog.TransformContext) {
+				m := tCtx.GetLogRecord().Attributes().PutEmptyMap("test")
+				m.PutStr("k1", "v1")
+				m.PutStr("k2", "v2__!__v2")
+			},
+		},
 		{
 			statement: `set(attributes["test"], Seconds(Duration("1m")))`,
 			want: func(tCtx ottllog.TransformContext) {
diff --git a/pkg/ottl/ottlfuncs/README.md b/pkg/ottl/ottlfuncs/README.md
index f4d6923e96f9..2f2a7ce9a7f8 100644
--- a/pkg/ottl/ottlfuncs/README.md
+++ b/pkg/ottl/ottlfuncs/README.md
@@ -410,6 +410,7 @@ Available Converters:
 - [Nanoseconds](#nanoseconds)
 - [Now](#now)
 - [ParseJSON](#parsejson)
+- [ParseKeyValue](#parsekeyvalue)
 - [Seconds](#seconds)
 - [SHA1](#sha1)
 - [SHA256](#sha256)
@@ -840,6 +841,26 @@ Examples:
 
 - `ParseJSON(body)`
 
+### ParseKeyValue
+
+`ParseKeyValue(target, Optional[delimiter], Optional[pair_delimiter])`
+
+The `ParseKeyValue` Converter returns a `pcommon.Map` that is a result of parsing the target string for key value pairs.
+
+`target` is a Getter that returns a string. `delimiter` is an optional string that is used to split the key and value in a pair, the default is `=`. `pair_delimiter` is an optional string that is used to split key value pairs, the default is white space.
+
+For example, the following target `"k1=v1 k2=v2 k3=v3"` will use default delimiters and be parsed into the following map:
+```
+{ "k1": "v1", "k2": "v2", "k3": "v3" }
+```
+
+Examples:
+
+- `ParseKeyValue("k1=v1 k2=v2 k3=v3")`
+- `ParseKeyValue("k1!v1_k2!v2_k3!v3", "!", "_")`
+- `ParseKeyValue(attributes["pairs"])`
+
+
 ### Seconds
 
 `Seconds(value)`

From 885a56627ae04d35619129c7893d725181142dae Mon Sep 17 00:00:00 2001
From: Dakota Paasman <dpaasman00@gmail.com>
Date: Mon, 5 Feb 2024 13:59:38 -0500
Subject: [PATCH 3/9] internal feedback

---
 pkg/ottl/ottlfuncs/func_parse_key_value.go    | 52 +++++++++++++------
 .../ottlfuncs/func_parse_key_value_test.go    | 44 ++++++++++++++++
 2 files changed, 81 insertions(+), 15 deletions(-)

diff --git a/pkg/ottl/ottlfuncs/func_parse_key_value.go b/pkg/ottl/ottlfuncs/func_parse_key_value.go
index 14aa09f1e472..759c100892a3 100644
--- a/pkg/ottl/ottlfuncs/func_parse_key_value.go
+++ b/pkg/ottl/ottlfuncs/func_parse_key_value.go
@@ -38,9 +38,10 @@ func parseKeyValue[K any](target ottl.StringGetter[K], d ottl.Optional[string],
 	pair_delimiter := " "
 	if !p.IsEmpty() {
 		pair_delimiter = p.Get()
-		if pair_delimiter == delimiter {
-			return nil, fmt.Errorf("pair delimiter \"%s\" cannot be equal to delimiter \"%s\"", pair_delimiter, delimiter)
-		}
+	}
+
+	if pair_delimiter == delimiter {
+		return nil, fmt.Errorf("pair delimiter \"%s\" cannot be equal to delimiter \"%s\"", pair_delimiter, delimiter)
 	}
 
 	return func(ctx context.Context, tCtx K) (any, error) {
@@ -53,11 +54,16 @@ func parseKeyValue[K any](target ottl.StringGetter[K], d ottl.Optional[string],
 			return nil, fmt.Errorf("cannot parse from empty target")
 		}
 
+		pairs, err := splitString(source, pair_delimiter)
+		if err != nil {
+			return nil, fmt.Errorf("splitting pairs failed: %w", err)
+		}
+
 		parsed := make(map[string]any)
-		for _, s := range splitString(source, pair_delimiter) {
-			pair := strings.SplitN(s, delimiter, 2)
+		for _, p := range pairs {
+			pair := strings.SplitN(p, delimiter, 2)
 			if len(pair) != 2 {
-				return nil, fmt.Errorf("cannot split '%s' into 2 items, got %d", s, len(pair))
+				return nil, fmt.Errorf("cannot split '%s' into 2 items, got %d", p, len(pair))
 			}
 			key := strings.TrimSpace(strings.Trim(pair[0], "\"'"))
 			value := strings.TrimSpace(strings.Trim(pair[1], "\"'"))
@@ -70,31 +76,47 @@ func parseKeyValue[K any](target ottl.StringGetter[K], d ottl.Optional[string],
 	}, nil
 }
 
-func splitString(input, delimiter string) []string {
+// splitString will split the input on the delimiter and return the resulting slice.
+// `strings.Split` is not used because it does not respect quotes and will split if the delimiter appears in a quoted value
+func splitString(input, delimiter string) ([]string, error) {
 	var result []string
+	quoteType := ""
 	inQuotes := false
 	currentPair := ""
 	delimiterLength := len(delimiter)
 
-	for i := 0; i < len(input); i++ {
-		if i+delimiterLength <= len(input) && input[i:i+delimiterLength] == delimiter && !inQuotes {
+	i := 0
+	for i < len(input) {
+		if !inQuotes && i+delimiterLength <= len(input) && input[i:i+delimiterLength] == delimiter {
 			if currentPair == "" {
+				i++
 				continue
 			}
 			result = append(result, currentPair)
 			currentPair = ""
-			i += delimiterLength - 1
+			i += delimiterLength
+			continue
 		} else if input[i] == '"' || input[i] == '\'' {
-			inQuotes = !inQuotes
-			currentPair += string(input[i])
-		} else {
-			currentPair += string(input[i])
+			if inQuotes {
+				if quoteType == string(input[i]) {
+					inQuotes = !inQuotes
+				}
+			} else {
+				quoteType = string(input[i])
+				inQuotes = !inQuotes
+			}
 		}
+		currentPair += string(input[i])
+		i++
+	}
+
+	if inQuotes {
+		return nil, fmt.Errorf("never reached end of a quoted value, failed to parse input")
 	}
 
 	if currentPair != "" {
 		result = append(result, currentPair)
 	}
 
-	return result
+	return result, nil
 }
diff --git a/pkg/ottl/ottlfuncs/func_parse_key_value_test.go b/pkg/ottl/ottlfuncs/func_parse_key_value_test.go
index e7d4d12d4da1..f153063be311 100644
--- a/pkg/ottl/ottlfuncs/func_parse_key_value_test.go
+++ b/pkg/ottl/ottlfuncs/func_parse_key_value_test.go
@@ -54,6 +54,20 @@ func Test_parseKeyValue(t *testing.T) {
 				"translated_src_ip": "96.63.176.3",
 			},
 		},
+		{
+			name: "embedded double quotes in single quoted value",
+			target: ottl.StandardStringGetter[any]{
+				Getter: func(ctx context.Context, tCtx any) (any, error) {
+					return `a=b c='this is a "co ol" value'`, nil
+				},
+			},
+			delimiter:      ottl.Optional[string]{},
+			pair_delimiter: ottl.Optional[string]{},
+			expected: map[string]any{
+				"a": "b",
+				"c": "this is a \"co ol\" value",
+			},
+		},
 		{
 			name: "double quotes",
 			target: ottl.StandardStringGetter[any]{
@@ -187,6 +201,20 @@ hello!!world  `, nil
 				"k3": "v3=",
 			},
 		},
+		{
+			name: "double quotes",
+			target: ottl.StandardStringGetter[any]{
+				Getter: func(ctx context.Context, tCtx any) (any, error) {
+					return `a=b c='this is a "cool" value'`, nil
+				},
+			},
+			delimiter:      ottl.Optional[string]{},
+			pair_delimiter: ottl.Optional[string]{},
+			expected: map[string]any{
+				"a": "b",
+				"c": "this is a \"cool\" value",
+			},
+		},
 	}
 
 	for _, tt := range tests {
@@ -225,6 +253,10 @@ func Test_parseKeyValue_equal_delimiters(t *testing.T) {
 	pair_delimiter := ottl.NewTestingOptional[string]("=")
 	_, err := parseKeyValue[any](target, delimiter, pair_delimiter)
 	assert.Error(t, err)
+
+	delimiter = ottl.NewTestingOptional[string](" ")
+	_, err = parseKeyValue[any](target, delimiter, ottl.Optional[string]{})
+	assert.Error(t, err)
 }
 
 func Test_parseKeyValue_bad_target(t *testing.T) {
@@ -268,3 +300,15 @@ func Test_parseKeyValue_bad_split(t *testing.T) {
 	_, err = exprFunc(context.Background(), nil)
 	assert.Error(t, err)
 }
+
+func Test_parseKeyValue_mismatch_quotes(t *testing.T) {
+	target := ottl.StandardStringGetter[any]{
+		Getter: func(ctx context.Context, tCtx any) (any, error) {
+			return `k1=v1 k2='v2"`, nil
+		},
+	}
+	exprFunc, err := parseKeyValue[any](target, ottl.Optional[string]{}, ottl.Optional[string]{})
+	assert.NoError(t, err)
+	_, err = exprFunc(context.Background(), nil)
+	assert.Error(t, err)
+}

From 967289ccbe8a2ba2e63036f994cef28f2fc82e6d Mon Sep 17 00:00:00 2001
From: Dakota Paasman <dpaasman00@gmail.com>
Date: Mon, 5 Feb 2024 14:45:22 -0500
Subject: [PATCH 4/9] name changes & remove inQuotes

---
 pkg/ottl/ottlfuncs/func_parse_key_value.go | 34 ++++++++++------------
 1 file changed, 16 insertions(+), 18 deletions(-)

diff --git a/pkg/ottl/ottlfuncs/func_parse_key_value.go b/pkg/ottl/ottlfuncs/func_parse_key_value.go
index 759c100892a3..c1ac1d06d25f 100644
--- a/pkg/ottl/ottlfuncs/func_parse_key_value.go
+++ b/pkg/ottl/ottlfuncs/func_parse_key_value.go
@@ -35,13 +35,13 @@ func parseKeyValue[K any](target ottl.StringGetter[K], d ottl.Optional[string],
 		delimiter = d.Get()
 	}
 
-	pair_delimiter := " "
+	pairDelimiter := " "
 	if !p.IsEmpty() {
-		pair_delimiter = p.Get()
+		pairDelimiter = p.Get()
 	}
 
-	if pair_delimiter == delimiter {
-		return nil, fmt.Errorf("pair delimiter \"%s\" cannot be equal to delimiter \"%s\"", pair_delimiter, delimiter)
+	if pairDelimiter == delimiter {
+		return nil, fmt.Errorf("pair delimiter \"%s\" cannot be equal to delimiter \"%s\"", pairDelimiter, delimiter)
 	}
 
 	return func(ctx context.Context, tCtx K) (any, error) {
@@ -54,7 +54,7 @@ func parseKeyValue[K any](target ottl.StringGetter[K], d ottl.Optional[string],
 			return nil, fmt.Errorf("cannot parse from empty target")
 		}
 
-		pairs, err := splitString(source, pair_delimiter)
+		pairs, err := splitPairs(source, pairDelimiter)
 		if err != nil {
 			return nil, fmt.Errorf("splitting pairs failed: %w", err)
 		}
@@ -76,18 +76,17 @@ func parseKeyValue[K any](target ottl.StringGetter[K], d ottl.Optional[string],
 	}, nil
 }
 
-// splitString will split the input on the delimiter and return the resulting slice.
+// splitPairs will split the input on the pairDelimiter and return the resulting slice.
 // `strings.Split` is not used because it does not respect quotes and will split if the delimiter appears in a quoted value
-func splitString(input, delimiter string) ([]string, error) {
+func splitPairs(input, pairDelimiter string) ([]string, error) {
 	var result []string
-	quoteType := ""
-	inQuotes := false
 	currentPair := ""
-	delimiterLength := len(delimiter)
+	delimiterLength := len(pairDelimiter)
+	quoteChar := "" // "" means we are not in quotes
 
 	i := 0
 	for i < len(input) {
-		if !inQuotes && i+delimiterLength <= len(input) && input[i:i+delimiterLength] == delimiter {
+		if quoteChar == "" && i+delimiterLength <= len(input) && input[i:i+delimiterLength] == pairDelimiter {
 			if currentPair == "" {
 				i++
 				continue
@@ -97,21 +96,20 @@ func splitString(input, delimiter string) ([]string, error) {
 			i += delimiterLength
 			continue
 		} else if input[i] == '"' || input[i] == '\'' {
-			if inQuotes {
-				if quoteType == string(input[i]) {
-					inQuotes = !inQuotes
+			if quoteChar != "" {
+				if quoteChar == string(input[i]) {
+					quoteChar = ""
 				}
 			} else {
-				quoteType = string(input[i])
-				inQuotes = !inQuotes
+				quoteChar = string(input[i])
 			}
 		}
 		currentPair += string(input[i])
 		i++
 	}
 
-	if inQuotes {
-		return nil, fmt.Errorf("never reached end of a quoted value, failed to parse input")
+	if quoteChar != "" {
+		return nil, fmt.Errorf("never reached end of a quoted value")
 	}
 
 	if currentPair != "" {

From 2ecf32deedb5114ff4a5620582fd84dcdc39d441 Mon Sep 17 00:00:00 2001
From: Dakota Paasman <dpaasman00@gmail.com>
Date: Tue, 6 Feb 2024 15:36:46 -0500
Subject: [PATCH 5/9] update parsing to reflect changes made to stanza keyvalue
 parser

---
 pkg/ottl/ottlfuncs/func_parse_key_value.go    | 40 +++++++++----------
 .../ottlfuncs/func_parse_key_value_test.go    |  6 +--
 2 files changed, 22 insertions(+), 24 deletions(-)

diff --git a/pkg/ottl/ottlfuncs/func_parse_key_value.go b/pkg/ottl/ottlfuncs/func_parse_key_value.go
index c1ac1d06d25f..188225bb8a86 100644
--- a/pkg/ottl/ottlfuncs/func_parse_key_value.go
+++ b/pkg/ottl/ottlfuncs/func_parse_key_value.go
@@ -65,8 +65,8 @@ func parseKeyValue[K any](target ottl.StringGetter[K], d ottl.Optional[string],
 			if len(pair) != 2 {
 				return nil, fmt.Errorf("cannot split '%s' into 2 items, got %d", p, len(pair))
 			}
-			key := strings.TrimSpace(strings.Trim(pair[0], "\"'"))
-			value := strings.TrimSpace(strings.Trim(pair[1], "\"'"))
+			key := strings.TrimSpace(pair[0])
+			value := strings.TrimSpace(pair[1])
 			parsed[key] = value
 		}
 
@@ -84,36 +84,34 @@ func splitPairs(input, pairDelimiter string) ([]string, error) {
 	delimiterLength := len(pairDelimiter)
 	quoteChar := "" // "" means we are not in quotes
 
-	i := 0
-	for i < len(input) {
-		if quoteChar == "" && i+delimiterLength <= len(input) && input[i:i+delimiterLength] == pairDelimiter {
-			if currentPair == "" {
-				i++
+	for i := 0; i < len(input); i++ {
+		if quoteChar == "" && i+delimiterLength <= len(input) && input[i:i+delimiterLength] == pairDelimiter { // delimiter
+			if currentPair == "" { // leading || trailing delimiter; ignore
 				continue
 			}
 			result = append(result, currentPair)
 			currentPair = ""
-			i += delimiterLength
+			i += delimiterLength - 1
+			continue
+		}
+
+		if quoteChar == "" && (input[i] == '"' || input[i] == '\'') { // start of quote
+			quoteChar = string(input[i])
 			continue
-		} else if input[i] == '"' || input[i] == '\'' {
-			if quoteChar != "" {
-				if quoteChar == string(input[i]) {
-					quoteChar = ""
-				}
-			} else {
-				quoteChar = string(input[i])
-			}
 		}
+		if string(input[i]) == quoteChar { // end of quote
+			quoteChar = ""
+			continue
+		}
+
 		currentPair += string(input[i])
-		i++
 	}
 
-	if quoteChar != "" {
+	if quoteChar != "" { // check for closed quotes
 		return nil, fmt.Errorf("never reached end of a quoted value")
 	}
-
-	if currentPair != "" {
-		result = append(result, currentPair)
+	if currentPair != "" { // avoid adding empty value bc of a trailing delimiter
+		return append(result, currentPair), nil
 	}
 
 	return result, nil
diff --git a/pkg/ottl/ottlfuncs/func_parse_key_value_test.go b/pkg/ottl/ottlfuncs/func_parse_key_value_test.go
index f153063be311..6b1200fae034 100644
--- a/pkg/ottl/ottlfuncs/func_parse_key_value_test.go
+++ b/pkg/ottl/ottlfuncs/func_parse_key_value_test.go
@@ -202,17 +202,17 @@ hello!!world  `, nil
 			},
 		},
 		{
-			name: "double quotes",
+			name: " embedded double quotes end single quoted value",
 			target: ottl.StandardStringGetter[any]{
 				Getter: func(ctx context.Context, tCtx any) (any, error) {
-					return `a=b c='this is a "cool" value'`, nil
+					return `a=b c='this is a "co ol"'`, nil
 				},
 			},
 			delimiter:      ottl.Optional[string]{},
 			pair_delimiter: ottl.Optional[string]{},
 			expected: map[string]any{
 				"a": "b",
-				"c": "this is a \"cool\" value",
+				"c": "this is a \"co ol\"",
 			},
 		},
 	}

From 6b0a26d6806fa5d4fd6798d2dff3c66c70d3aed5 Mon Sep 17 00:00:00 2001
From: Dakota Paasman <dpaasman00@gmail.com>
Date: Thu, 8 Feb 2024 08:28:57 -0500
Subject: [PATCH 6/9] add license

---
 pkg/ottl/ottlfuncs/func_parse_key_value.go      | 3 +++
 pkg/ottl/ottlfuncs/func_parse_key_value_test.go | 3 +++
 2 files changed, 6 insertions(+)

diff --git a/pkg/ottl/ottlfuncs/func_parse_key_value.go b/pkg/ottl/ottlfuncs/func_parse_key_value.go
index 188225bb8a86..44327060e664 100644
--- a/pkg/ottl/ottlfuncs/func_parse_key_value.go
+++ b/pkg/ottl/ottlfuncs/func_parse_key_value.go
@@ -1,3 +1,6 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
 package ottlfuncs
 
 import (
diff --git a/pkg/ottl/ottlfuncs/func_parse_key_value_test.go b/pkg/ottl/ottlfuncs/func_parse_key_value_test.go
index 6b1200fae034..b6efa35abb99 100644
--- a/pkg/ottl/ottlfuncs/func_parse_key_value_test.go
+++ b/pkg/ottl/ottlfuncs/func_parse_key_value_test.go
@@ -1,3 +1,6 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
 package ottlfuncs
 
 import (

From 0dbc0d92cdc1ba5399a04ab7abdb0e9d71d17832 Mon Sep 17 00:00:00 2001
From: Dakota Paasman <dpaasman00@gmail.com>
Date: Mon, 12 Feb 2024 14:06:40 -0500
Subject: [PATCH 7/9] put pair parsing into internal pkg, add some more unit
 tests, update fmt specifier for errs

---
 internal/coreinternal/parseutils/doc.go       |   4 +
 .../coreinternal/parseutils/package_test.go   |  14 ++
 internal/coreinternal/parseutils/parser.go    |  49 +++++
 .../coreinternal/parseutils/parser_test.go    | 186 ++++++++++++++++++
 pkg/ottl/ottlfuncs/README.md                  |   2 +-
 pkg/ottl/ottlfuncs/func_parse_key_value.go    |  54 +----
 .../ottlfuncs/func_parse_key_value_test.go    | 143 ++++++++++----
 7 files changed, 361 insertions(+), 91 deletions(-)
 create mode 100644 internal/coreinternal/parseutils/doc.go
 create mode 100644 internal/coreinternal/parseutils/package_test.go
 create mode 100644 internal/coreinternal/parseutils/parser.go
 create mode 100644 internal/coreinternal/parseutils/parser_test.go

diff --git a/internal/coreinternal/parseutils/doc.go b/internal/coreinternal/parseutils/doc.go
new file mode 100644
index 000000000000..f63f940df0a8
--- /dev/null
+++ b/internal/coreinternal/parseutils/doc.go
@@ -0,0 +1,4 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package parseutils // import "github.com/open-telemetry/opentelemetry-collector-contrib/internal/coreinternal/parseutils"
diff --git a/internal/coreinternal/parseutils/package_test.go b/internal/coreinternal/parseutils/package_test.go
new file mode 100644
index 000000000000..20e63515f3af
--- /dev/null
+++ b/internal/coreinternal/parseutils/package_test.go
@@ -0,0 +1,14 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package parseutils
+
+import (
+	"testing"
+
+	"go.uber.org/goleak"
+)
+
+func TestMain(m *testing.M) {
+	goleak.VerifyTestMain(m)
+}
diff --git a/internal/coreinternal/parseutils/parser.go b/internal/coreinternal/parseutils/parser.go
new file mode 100644
index 000000000000..03dfc7096677
--- /dev/null
+++ b/internal/coreinternal/parseutils/parser.go
@@ -0,0 +1,49 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package parseutils
+
+import "fmt"
+
+// SplitString will split the input on the delimiter and return the resulting slice while respecting quotes. Outer quotes are stripped.
+// Use in place of `strings.Split` when quotes need to be respected.
+// Requires `delimiter` not be an empty string
+func SplitString(input, delimiter string) ([]string, error) {
+	var result []string
+	current := ""
+	delimiterLength := len(delimiter)
+	quoteChar := "" // "" means we are not in quotes
+
+	for i := 0; i < len(input); i++ {
+		if quoteChar == "" && i+delimiterLength <= len(input) && input[i:i+delimiterLength] == delimiter { // delimiter
+			if current == "" { // leading || trailing delimiter; ignore
+				i += delimiterLength - 1
+				continue
+			}
+			result = append(result, current)
+			current = ""
+			i += delimiterLength - 1
+			continue
+		}
+
+		if quoteChar == "" && (input[i] == '"' || input[i] == '\'') { // start of quote
+			quoteChar = string(input[i])
+			continue
+		}
+		if string(input[i]) == quoteChar { // end of quote
+			quoteChar = ""
+			continue
+		}
+
+		current += string(input[i])
+	}
+
+	if quoteChar != "" { // check for closed quotes
+		return nil, fmt.Errorf("never reached the end of a quoted value")
+	}
+	if current != "" { // avoid adding empty value bc of a trailing delimiter
+		return append(result, current), nil
+	}
+
+	return result, nil
+}
diff --git a/internal/coreinternal/parseutils/parser_test.go b/internal/coreinternal/parseutils/parser_test.go
new file mode 100644
index 000000000000..d78ac812604f
--- /dev/null
+++ b/internal/coreinternal/parseutils/parser_test.go
@@ -0,0 +1,186 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package parseutils
+
+import (
+	"fmt"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func Test_SplitString(t *testing.T) {
+	testCases := []struct {
+		name        string
+		input       string
+		delimiter   string
+		expected    []string
+		expectedErr error
+	}{
+		{
+			name:      "simple",
+			input:     "a b c",
+			delimiter: " ",
+			expected: []string{
+				"a",
+				"b",
+				"c",
+			},
+		},
+		{
+			name:      "single quotes",
+			input:     "a 'b c d'",
+			delimiter: " ",
+			expected: []string{
+				"a",
+				"b c d",
+			},
+		},
+		{
+			name:      "double quotes",
+			input:     `a " b c " d`,
+			delimiter: " ",
+			expected: []string{
+				"a",
+				" b c ",
+				"d",
+			},
+		},
+		{
+			name:      "multi-char delimiter",
+			input:     "abc!@!  def !@! g",
+			delimiter: "!@!",
+			expected: []string{
+				"abc",
+				"  def ",
+				" g",
+			},
+		},
+		{
+			name:      "leading and trailing delimiters",
+			input:     "   name=ottl        func=key_value   hello=world ",
+			delimiter: " ",
+			expected: []string{
+				"name=ottl",
+				"func=key_value",
+				"hello=world",
+			},
+		},
+		{
+			name:      "embedded double quotes in single quoted value",
+			input:     `ab c='this is a "co ol" value'`,
+			delimiter: " ",
+			expected: []string{
+				"ab",
+				`c=this is a "co ol" value`,
+			},
+		},
+		{
+			name:      "embedded double quotes end single quoted value",
+			input:     `ab c='this is a "co ol"'`,
+			delimiter: " ",
+			expected: []string{
+				"ab",
+				`c=this is a "co ol"`,
+			},
+		},
+		{
+			name:      "quoted values include whitespace",
+			input:     `name="    ottl " func="  key_ value"`,
+			delimiter: " ",
+			expected: []string{
+				"name=    ottl ",
+				"func=  key_ value",
+			},
+		},
+		{
+			name:      "delimiter longer than input",
+			input:     "abc",
+			delimiter: "aaaa",
+			expected: []string{
+				"abc",
+			},
+		},
+		{
+			name:      "delimiter not found",
+			input:     "a b c",
+			delimiter: "!",
+			expected: []string{
+				"a b c",
+			},
+		},
+		{
+			name: "newlines in input",
+			input: `a
+b
+c`,
+			delimiter: " ",
+			expected: []string{
+				"a\nb\nc",
+			},
+		},
+		{
+			name: "newline delimiter",
+			input: `a b c
+d e f
+g 
+h`,
+			delimiter: "\n",
+			expected: []string{
+				"a b c",
+				"d e f",
+				"g ",
+				"h",
+			},
+		},
+		{
+			name:      "empty input",
+			input:     "",
+			delimiter: " ",
+			expected:  nil,
+		},
+		{
+			name:      "equal input and delimiter",
+			input:     "abc",
+			delimiter: "abc",
+			expected:  nil,
+		},
+		{
+			name:        "unclosed quotes",
+			input:       "a 'b c",
+			delimiter:   " ",
+			expectedErr: fmt.Errorf("never reached the end of a quoted value"),
+		},
+		{
+			name:        "mismatched quotes",
+			input:       `a 'b c' "d '`,
+			delimiter:   " ",
+			expectedErr: fmt.Errorf("never reached the end of a quoted value"),
+		},
+		{
+			name:      "tab delimiters",
+			input:     "a	b	c",
+			delimiter: "\t",
+			expected: []string{
+				"a",
+				"b",
+				"c",
+			},
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			result, err := SplitString(tc.input, tc.delimiter)
+
+			if tc.expectedErr == nil {
+				assert.NoError(t, err)
+				assert.Equal(t, tc.expected, result)
+			} else {
+				assert.EqualError(t, err, tc.expectedErr.Error())
+				assert.Nil(t, result)
+			}
+		})
+	}
+}
diff --git a/pkg/ottl/ottlfuncs/README.md b/pkg/ottl/ottlfuncs/README.md
index 2f2a7ce9a7f8..d99125af2868 100644
--- a/pkg/ottl/ottlfuncs/README.md
+++ b/pkg/ottl/ottlfuncs/README.md
@@ -847,7 +847,7 @@ Examples:
 
 The `ParseKeyValue` Converter returns a `pcommon.Map` that is a result of parsing the target string for key value pairs.
 
-`target` is a Getter that returns a string. `delimiter` is an optional string that is used to split the key and value in a pair, the default is `=`. `pair_delimiter` is an optional string that is used to split key value pairs, the default is white space.
+`target` is a Getter that returns a string. `delimiter` is an optional string that is used to split the key and value in a pair, the default is `=`. `pair_delimiter` is an optional string that is used to split key value pairs, the default is a single space (` `).
 
 For example, the following target `"k1=v1 k2=v2 k3=v3"` will use default delimiters and be parsed into the following map:
 ```
diff --git a/pkg/ottl/ottlfuncs/func_parse_key_value.go b/pkg/ottl/ottlfuncs/func_parse_key_value.go
index 44327060e664..21eff3b2e014 100644
--- a/pkg/ottl/ottlfuncs/func_parse_key_value.go
+++ b/pkg/ottl/ottlfuncs/func_parse_key_value.go
@@ -8,6 +8,7 @@ import (
 	"fmt"
 	"strings"
 
+	"github.com/open-telemetry/opentelemetry-collector-contrib/internal/coreinternal/parseutils"
 	"github.com/open-telemetry/opentelemetry-collector-contrib/pkg/ottl"
 	"go.opentelemetry.io/collector/pdata/pcommon"
 )
@@ -34,17 +35,17 @@ func createParseKeyValueFunction[K any](_ ottl.FunctionContext, oArgs ottl.Argum
 
 func parseKeyValue[K any](target ottl.StringGetter[K], d ottl.Optional[string], p ottl.Optional[string]) (ottl.ExprFunc[K], error) {
 	delimiter := "="
-	if !d.IsEmpty() {
+	if !d.IsEmpty() && d.Get() != "" {
 		delimiter = d.Get()
 	}
 
 	pairDelimiter := " "
-	if !p.IsEmpty() {
+	if !p.IsEmpty() && p.Get() != "" {
 		pairDelimiter = p.Get()
 	}
 
 	if pairDelimiter == delimiter {
-		return nil, fmt.Errorf("pair delimiter \"%s\" cannot be equal to delimiter \"%s\"", pairDelimiter, delimiter)
+		return nil, fmt.Errorf("pair delimiter %q cannot be equal to delimiter %q", pairDelimiter, delimiter)
 	}
 
 	return func(ctx context.Context, tCtx K) (any, error) {
@@ -57,16 +58,16 @@ func parseKeyValue[K any](target ottl.StringGetter[K], d ottl.Optional[string],
 			return nil, fmt.Errorf("cannot parse from empty target")
 		}
 
-		pairs, err := splitPairs(source, pairDelimiter)
+		pairs, err := parseutils.SplitString(source, pairDelimiter)
 		if err != nil {
-			return nil, fmt.Errorf("splitting pairs failed: %w", err)
+			return nil, fmt.Errorf("splitting source %q into pairs failed: %w", source, err)
 		}
 
 		parsed := make(map[string]any)
 		for _, p := range pairs {
 			pair := strings.SplitN(p, delimiter, 2)
 			if len(pair) != 2 {
-				return nil, fmt.Errorf("cannot split '%s' into 2 items, got %d", p, len(pair))
+				return nil, fmt.Errorf("cannot split %q into 2 items, got %d item(s)", p, len(pair))
 			}
 			key := strings.TrimSpace(pair[0])
 			value := strings.TrimSpace(pair[1])
@@ -78,44 +79,3 @@ func parseKeyValue[K any](target ottl.StringGetter[K], d ottl.Optional[string],
 		return result, err
 	}, nil
 }
-
-// splitPairs will split the input on the pairDelimiter and return the resulting slice.
-// `strings.Split` is not used because it does not respect quotes and will split if the delimiter appears in a quoted value
-func splitPairs(input, pairDelimiter string) ([]string, error) {
-	var result []string
-	currentPair := ""
-	delimiterLength := len(pairDelimiter)
-	quoteChar := "" // "" means we are not in quotes
-
-	for i := 0; i < len(input); i++ {
-		if quoteChar == "" && i+delimiterLength <= len(input) && input[i:i+delimiterLength] == pairDelimiter { // delimiter
-			if currentPair == "" { // leading || trailing delimiter; ignore
-				continue
-			}
-			result = append(result, currentPair)
-			currentPair = ""
-			i += delimiterLength - 1
-			continue
-		}
-
-		if quoteChar == "" && (input[i] == '"' || input[i] == '\'') { // start of quote
-			quoteChar = string(input[i])
-			continue
-		}
-		if string(input[i]) == quoteChar { // end of quote
-			quoteChar = ""
-			continue
-		}
-
-		currentPair += string(input[i])
-	}
-
-	if quoteChar != "" { // check for closed quotes
-		return nil, fmt.Errorf("never reached end of a quoted value")
-	}
-	if currentPair != "" { // avoid adding empty value bc of a trailing delimiter
-		return append(result, currentPair), nil
-	}
-
-	return result, nil
-}
diff --git a/pkg/ottl/ottlfuncs/func_parse_key_value_test.go b/pkg/ottl/ottlfuncs/func_parse_key_value_test.go
index b6efa35abb99..02b67ee79da2 100644
--- a/pkg/ottl/ottlfuncs/func_parse_key_value_test.go
+++ b/pkg/ottl/ottlfuncs/func_parse_key_value_test.go
@@ -14,11 +14,11 @@ import (
 
 func Test_parseKeyValue(t *testing.T) {
 	tests := []struct {
-		name           string
-		target         ottl.StringGetter[any]
-		delimiter      ottl.Optional[string]
-		pair_delimiter ottl.Optional[string]
-		expected       map[string]any
+		name          string
+		target        ottl.StringGetter[any]
+		delimiter     ottl.Optional[string]
+		pairDelimiter ottl.Optional[string]
+		expected      map[string]any
 	}{
 		{
 			name: "simple",
@@ -27,8 +27,8 @@ func Test_parseKeyValue(t *testing.T) {
 					return "name=ottl func=key_value", nil
 				},
 			},
-			delimiter:      ottl.Optional[string]{},
-			pair_delimiter: ottl.Optional[string]{},
+			delimiter:     ottl.Optional[string]{},
+			pairDelimiter: ottl.Optional[string]{},
 			expected: map[string]any{
 				"name": "ottl",
 				"func": "key_value",
@@ -41,8 +41,8 @@ func Test_parseKeyValue(t *testing.T) {
 					return `name=ottl age=1 job="software engineering" location="grand rapids michigan" src="10.3.3.76" dst=172.217.0.10 protocol=udp sport=57112 port=443 translated_src_ip=96.63.176.3 translated_port=57112`, nil
 				},
 			},
-			delimiter:      ottl.Optional[string]{},
-			pair_delimiter: ottl.Optional[string]{},
+			delimiter:     ottl.Optional[string]{},
+			pairDelimiter: ottl.Optional[string]{},
 			expected: map[string]any{
 				"age":               "1",
 				"port":              "443",
@@ -64,8 +64,8 @@ func Test_parseKeyValue(t *testing.T) {
 					return `a=b c='this is a "co ol" value'`, nil
 				},
 			},
-			delimiter:      ottl.Optional[string]{},
-			pair_delimiter: ottl.Optional[string]{},
+			delimiter:     ottl.Optional[string]{},
+			pairDelimiter: ottl.Optional[string]{},
 			expected: map[string]any{
 				"a": "b",
 				"c": "this is a \"co ol\" value",
@@ -78,8 +78,8 @@ func Test_parseKeyValue(t *testing.T) {
 					return `requestClientApplication="Mozilla/5.0 (Windows NT 6.1; WOW64; rv:40.0) Gecko/20100101 Firefox/40.0"`, nil
 				},
 			},
-			delimiter:      ottl.Optional[string]{},
-			pair_delimiter: ottl.Optional[string]{},
+			delimiter:     ottl.Optional[string]{},
+			pairDelimiter: ottl.Optional[string]{},
 			expected: map[string]any{
 				"requestClientApplication": "Mozilla/5.0 (Windows NT 6.1; WOW64; rv:40.0) Gecko/20100101 Firefox/40.0",
 			},
@@ -91,8 +91,8 @@ func Test_parseKeyValue(t *testing.T) {
 					return "requestClientApplication='Mozilla/5.0 (Windows NT 6.1; WOW64; rv:40.0) Gecko/20100101 Firefox/40.0'", nil
 				},
 			},
-			delimiter:      ottl.Optional[string]{},
-			pair_delimiter: ottl.Optional[string]{},
+			delimiter:     ottl.Optional[string]{},
+			pairDelimiter: ottl.Optional[string]{},
 			expected: map[string]any{
 				"requestClientApplication": "Mozilla/5.0 (Windows NT 6.1; WOW64; rv:40.0) Gecko/20100101 Firefox/40.0",
 			},
@@ -104,8 +104,8 @@ func Test_parseKeyValue(t *testing.T) {
 					return `name="   ottl " func="  key_ value"`, nil
 				},
 			},
-			delimiter:      ottl.Optional[string]{},
-			pair_delimiter: ottl.Optional[string]{},
+			delimiter:     ottl.Optional[string]{},
+			pairDelimiter: ottl.Optional[string]{},
 			expected: map[string]any{
 				"name": "ottl",
 				"func": "key_ value",
@@ -118,8 +118,8 @@ func Test_parseKeyValue(t *testing.T) {
 					return "   name!ottl     func!key_value hello!world  ", nil
 				},
 			},
-			delimiter:      ottl.NewTestingOptional[string]("!"),
-			pair_delimiter: ottl.Optional[string]{},
+			delimiter:     ottl.NewTestingOptional[string]("!"),
+			pairDelimiter: ottl.Optional[string]{},
 			expected: map[string]any{
 				"name":  "ottl",
 				"func":  "key_value",
@@ -135,8 +135,8 @@ name!!ottl
 func!!key_value                      hello!!world  `, nil
 				},
 			},
-			delimiter:      ottl.NewTestingOptional[string]("!!"),
-			pair_delimiter: ottl.Optional[string]{},
+			delimiter:     ottl.NewTestingOptional[string]("!!"),
+			pairDelimiter: ottl.Optional[string]{},
 			expected: map[string]any{
 				"name":  "ottl",
 				"func":  "key_value",
@@ -152,8 +152,8 @@ func!!      key_value another!!pair
 hello!!world  `, nil
 				},
 			},
-			delimiter:      ottl.NewTestingOptional[string]("!!"),
-			pair_delimiter: ottl.NewTestingOptional[string]("\n"),
+			delimiter:     ottl.NewTestingOptional[string]("!!"),
+			pairDelimiter: ottl.NewTestingOptional[string]("\n"),
 			expected: map[string]any{
 				"name":  "ottl",
 				"func":  "key_value another!!pair",
@@ -167,8 +167,8 @@ hello!!world  `, nil
 					return `name="ottl="_func="=key_value"`, nil
 				},
 			},
-			delimiter:      ottl.Optional[string]{},
-			pair_delimiter: ottl.NewTestingOptional("_"),
+			delimiter:     ottl.Optional[string]{},
+			pairDelimiter: ottl.NewTestingOptional("_"),
 			expected: map[string]any{
 				"name": "ottl=",
 				"func": "=key_value",
@@ -181,8 +181,8 @@ hello!!world  `, nil
 					return `k1@*v1_!_k2@**v2_!__k3@@*v3__`, nil
 				},
 			},
-			delimiter:      ottl.NewTestingOptional("@*"),
-			pair_delimiter: ottl.NewTestingOptional("_!_"),
+			delimiter:     ottl.NewTestingOptional("@*"),
+			pairDelimiter: ottl.NewTestingOptional("_!_"),
 			expected: map[string]any{
 				"k1":   "v1",
 				"k2":   "*v2",
@@ -196,8 +196,8 @@ hello!!world  `, nil
 					return "   k1=v1   k2==v2       k3=v3= ", nil
 				},
 			},
-			delimiter:      ottl.Optional[string]{},
-			pair_delimiter: ottl.Optional[string]{},
+			delimiter:     ottl.Optional[string]{},
+			pairDelimiter: ottl.Optional[string]{},
 			expected: map[string]any{
 				"k1": "v1",
 				"k2": "=v2",
@@ -205,24 +205,66 @@ hello!!world  `, nil
 			},
 		},
 		{
-			name: " embedded double quotes end single quoted value",
+			name: "embedded double quotes end single quoted value",
 			target: ottl.StandardStringGetter[any]{
 				Getter: func(ctx context.Context, tCtx any) (any, error) {
 					return `a=b c='this is a "co ol"'`, nil
 				},
 			},
-			delimiter:      ottl.Optional[string]{},
-			pair_delimiter: ottl.Optional[string]{},
+			delimiter:     ottl.Optional[string]{},
+			pairDelimiter: ottl.Optional[string]{},
 			expected: map[string]any{
 				"a": "b",
 				"c": "this is a \"co ol\"",
 			},
 		},
+		{
+			name: "more quotes",
+			target: ottl.StandardStringGetter[any]{
+				Getter: func(ctx context.Context, tCtx any) (any, error) {
+					return "a=b c=d'='", nil
+				},
+			},
+			delimiter:     ottl.Optional[string]{},
+			pairDelimiter: ottl.Optional[string]{},
+			expected: map[string]any{
+				"a": "b",
+				"c": "d=",
+			},
+		},
+
+		{
+			name: "long pair delimiter",
+			target: ottl.StandardStringGetter[any]{
+				Getter: func(ctx context.Context, tCtx any) (any, error) {
+					return "a=b c=d", nil
+				},
+			},
+			delimiter:     ottl.Optional[string]{},
+			pairDelimiter: ottl.NewTestingOptional("aaaaaaaaaaaaaaaa"),
+			expected: map[string]any{
+				"a": "b c=d", // occurs because `SplitString()` returns original string and `strings.SplitN` with N=2 will split on just the first instance of delimiter("=")
+			},
+		},
+		{
+			name: "empty delimiters",
+			target: ottl.StandardStringGetter[any]{
+				Getter: func(ctx context.Context, tCtx any) (any, error) {
+					return "a=b c=d", nil
+				},
+			},
+			delimiter:     ottl.NewTestingOptional(""),
+			pairDelimiter: ottl.NewTestingOptional(""),
+			expected: map[string]any{
+				"a": "b",
+				"c": "d",
+			},
+		},
 	}
 
 	for _, tt := range tests {
-		t.Run(t.Name(), func(t *testing.T) {
-			exprFunc, err := parseKeyValue[any](tt.target, tt.delimiter, tt.pair_delimiter)
+		t.Run(tt.name, func(t *testing.T) {
+			exprFunc, err := parseKeyValue[any](tt.target, tt.delimiter, tt.pairDelimiter)
 			assert.NoError(t, err)
 
 			result, err := exprFunc(context.Background(), nil)
@@ -253,8 +295,8 @@ func Test_parseKeyValue_equal_delimiters(t *testing.T) {
 		},
 	}
 	delimiter := ottl.NewTestingOptional[string]("=")
-	pair_delimiter := ottl.NewTestingOptional[string]("=")
-	_, err := parseKeyValue[any](target, delimiter, pair_delimiter)
+	pairDelimiter := ottl.NewTestingOptional[string]("=")
+	_, err := parseKeyValue[any](target, delimiter, pairDelimiter)
 	assert.Error(t, err)
 
 	delimiter = ottl.NewTestingOptional[string](" ")
@@ -269,8 +311,8 @@ func Test_parseKeyValue_bad_target(t *testing.T) {
 		},
 	}
 	delimiter := ottl.NewTestingOptional[string]("=")
-	pair_delimiter := ottl.NewTestingOptional[string]("!")
-	exprFunc, err := parseKeyValue[any](target, delimiter, pair_delimiter)
+	pairDelimiter := ottl.NewTestingOptional[string]("!")
+	exprFunc, err := parseKeyValue[any](target, delimiter, pairDelimiter)
 	assert.NoError(t, err)
 	_, err = exprFunc(context.Background(), nil)
 	assert.Error(t, err)
@@ -283,8 +325,8 @@ func Test_parseKeyValue_empty_target(t *testing.T) {
 		},
 	}
 	delimiter := ottl.NewTestingOptional[string]("=")
-	pair_delimiter := ottl.NewTestingOptional[string]("!")
-	exprFunc, err := parseKeyValue[any](target, delimiter, pair_delimiter)
+	pairDelimiter := ottl.NewTestingOptional[string]("!")
+	exprFunc, err := parseKeyValue[any](target, delimiter, pairDelimiter)
 	assert.NoError(t, err)
 	_, err = exprFunc(context.Background(), nil)
 	assert.Error(t, err)
@@ -297,11 +339,11 @@ func Test_parseKeyValue_bad_split(t *testing.T) {
 		},
 	}
 	delimiter := ottl.NewTestingOptional[string]("=")
-	pair_delimiter := ottl.NewTestingOptional[string]("!")
-	exprFunc, err := parseKeyValue[any](target, delimiter, pair_delimiter)
+	pairDelimiter := ottl.NewTestingOptional[string]("!")
+	exprFunc, err := parseKeyValue[any](target, delimiter, pairDelimiter)
 	assert.NoError(t, err)
 	_, err = exprFunc(context.Background(), nil)
-	assert.Error(t, err)
+	assert.ErrorContains(t, err, "cannot split \"hello_world\" into 2 items, got 1 item(s)")
 }
 
 func Test_parseKeyValue_mismatch_quotes(t *testing.T) {
@@ -315,3 +357,18 @@ func Test_parseKeyValue_mismatch_quotes(t *testing.T) {
 	_, err = exprFunc(context.Background(), nil)
 	assert.Error(t, err)
 }
+
+func Test_parseKeyValue_bad_delimiter(t *testing.T) {
+	target := ottl.StandardStringGetter[any]{
+		Getter: func(ctx context.Context, tCtx any) (any, error) {
+			return "a=b c=d", nil
+		},
+	}
+
+	// covers too long of a delimiter && delimiter not found
+	delimiter := ottl.NewTestingOptional[string]("=============")
+	exprFunc, err := parseKeyValue[any](target, delimiter, ottl.Optional[string]{})
+	assert.NoError(t, err)
+	_, err = exprFunc(context.Background(), nil)
+	assert.ErrorContains(t, err, "cannot split \"a=b\" into 2 items, got 1 item(s)")
+}

From ca573d970112d10f39e2fc49f991731aea39fb63 Mon Sep 17 00:00:00 2001
From: Dakota Paasman <dpaasman00@gmail.com>
Date: Tue, 13 Feb 2024 07:44:08 -0500
Subject: [PATCH 8/9] update how empty string is handled

---
 pkg/ottl/ottlfuncs/func_parse_key_value.go    | 13 ++++++--
 .../ottlfuncs/func_parse_key_value_test.go    | 32 ++++++++++---------
 2 files changed, 27 insertions(+), 18 deletions(-)

diff --git a/pkg/ottl/ottlfuncs/func_parse_key_value.go b/pkg/ottl/ottlfuncs/func_parse_key_value.go
index 21eff3b2e014..71a6c6eab7df 100644
--- a/pkg/ottl/ottlfuncs/func_parse_key_value.go
+++ b/pkg/ottl/ottlfuncs/func_parse_key_value.go
@@ -8,9 +8,10 @@ import (
 	"fmt"
 	"strings"
 
+	"go.opentelemetry.io/collector/pdata/pcommon"
+
 	"github.com/open-telemetry/opentelemetry-collector-contrib/internal/coreinternal/parseutils"
 	"github.com/open-telemetry/opentelemetry-collector-contrib/pkg/ottl"
-	"go.opentelemetry.io/collector/pdata/pcommon"
 )
 
 type ParseKeyValueArguments[K any] struct {
@@ -35,12 +36,18 @@ func createParseKeyValueFunction[K any](_ ottl.FunctionContext, oArgs ottl.Argum
 
 func parseKeyValue[K any](target ottl.StringGetter[K], d ottl.Optional[string], p ottl.Optional[string]) (ottl.ExprFunc[K], error) {
 	delimiter := "="
-	if !d.IsEmpty() && d.Get() != "" {
+	if !d.IsEmpty() {
+		if d.Get() == "" {
+			return nil, fmt.Errorf("delimiter cannot be set to an empty string")
+		}
 		delimiter = d.Get()
 	}
 
 	pairDelimiter := " "
-	if !p.IsEmpty() && p.Get() != "" {
+	if !p.IsEmpty() {
+		if p.Get() == "" {
+			return nil, fmt.Errorf("pair delimiter cannot be set to an empty string")
+		}
 		pairDelimiter = p.Get()
 	}
 
diff --git a/pkg/ottl/ottlfuncs/func_parse_key_value_test.go b/pkg/ottl/ottlfuncs/func_parse_key_value_test.go
index 02b67ee79da2..77ad9a8c9431 100644
--- a/pkg/ottl/ottlfuncs/func_parse_key_value_test.go
+++ b/pkg/ottl/ottlfuncs/func_parse_key_value_test.go
@@ -7,9 +7,10 @@ import (
 	"context"
 	"testing"
 
-	"github.com/open-telemetry/opentelemetry-collector-contrib/pkg/ottl"
 	"github.com/stretchr/testify/assert"
 	"go.opentelemetry.io/collector/pdata/pcommon"
+
+	"github.com/open-telemetry/opentelemetry-collector-contrib/pkg/ottl"
 )
 
 func Test_parseKeyValue(t *testing.T) {
@@ -246,20 +247,6 @@ hello!!world  `, nil
 				"a": "b c=d", // occurs because `SplitString()` returns original string and `strings.SplitN` with N=2 will split on just the first instance of delimiter("=")
 			},
 		},
-		{
-			name: "empty delimiters",
-			target: ottl.StandardStringGetter[any]{
-				Getter: func(ctx context.Context, tCtx any) (any, error) {
-					return "a=b c=d", nil
-				},
-			},
-			delimiter:     ottl.NewTestingOptional(""),
-			pairDelimiter: ottl.NewTestingOptional(""),
-			expected: map[string]any{
-				"a": "b",
-				"c": "d",
-			},
-		},
 	}
 
 	for _, tt := range tests {
@@ -372,3 +359,18 @@ func Test_parseKeyValue_bad_delimiter(t *testing.T) {
 	_, err = exprFunc(context.Background(), nil)
 	assert.ErrorContains(t, err, "cannot split \"a=b\" into 2 items, got 1 item(s)")
 }
+
+func Test_parseKeyValue_empty_delimiters(t *testing.T) {
+	target := ottl.StandardStringGetter[any]{
+		Getter: func(ctx context.Context, tCtx any) (any, error) {
+			return "a=b c=d", nil
+		},
+	}
+	delimiter := ottl.NewTestingOptional[string]("")
+
+	_, err := parseKeyValue[any](target, delimiter, ottl.Optional[string]{})
+	assert.ErrorContains(t, err, "delimiter cannot be set to an empty string")
+
+	_, err = parseKeyValue[any](target, ottl.Optional[string]{}, delimiter)
+	assert.ErrorContains(t, err, "pair delimiter cannot be set to an empty string")
+}

From e1bbb38b026879ff2c2cd2abc4db6e83b2a14844 Mon Sep 17 00:00:00 2001
From: Dakota Paasman <dpaasman00@gmail.com>
Date: Thu, 15 Feb 2024 07:27:42 -0500
Subject: [PATCH 9/9] move key-value split into parseutils

---
 internal/coreinternal/parseutils/parser.go    | 28 +++++-
 .../coreinternal/parseutils/parser_test.go    | 90 +++++++++++++++++++
 pkg/ottl/ottlfuncs/README.md                  |  2 +-
 pkg/ottl/ottlfuncs/func_parse_key_value.go    | 15 +---
 .../ottlfuncs/func_parse_key_value_test.go    |  4 +-
 5 files changed, 123 insertions(+), 16 deletions(-)

diff --git a/internal/coreinternal/parseutils/parser.go b/internal/coreinternal/parseutils/parser.go
index 03dfc7096677..2758161ec565 100644
--- a/internal/coreinternal/parseutils/parser.go
+++ b/internal/coreinternal/parseutils/parser.go
@@ -1,9 +1,14 @@
 // Copyright The OpenTelemetry Authors
 // SPDX-License-Identifier: Apache-2.0
 
-package parseutils
+package parseutils // import "github.com/open-telemetry/opentelemetry-collector-contrib/internal/coreinternal/parseutils"
 
-import "fmt"
+import (
+	"fmt"
+	"strings"
+
+	"go.uber.org/multierr"
+)
 
 // SplitString will split the input on the delimiter and return the resulting slice while respecting quotes. Outer quotes are stripped.
 // Use in place of `strings.Split` when quotes need to be respected.
@@ -47,3 +52,22 @@ func SplitString(input, delimiter string) ([]string, error) {
 
 	return result, nil
 }
+
+// ParseKeyValuePairs will split each string in `pairs` on the `delimiter` into a key and value string that get added to a map and returned.
+func ParseKeyValuePairs(pairs []string, delimiter string) (map[string]any, error) {
+	parsed := make(map[string]any)
+	var err error
+	for _, p := range pairs {
+		pair := strings.SplitN(p, delimiter, 2)
+		if len(pair) != 2 {
+			err = multierr.Append(err, fmt.Errorf("cannot split %q into 2 items, got %d item(s)", p, len(pair)))
+			continue
+		}
+
+		key := strings.TrimSpace(pair[0])
+		value := strings.TrimSpace(pair[1])
+
+		parsed[key] = value
+	}
+	return parsed, err
+}
diff --git a/internal/coreinternal/parseutils/parser_test.go b/internal/coreinternal/parseutils/parser_test.go
index d78ac812604f..f4f8f4b14e5d 100644
--- a/internal/coreinternal/parseutils/parser_test.go
+++ b/internal/coreinternal/parseutils/parser_test.go
@@ -184,3 +184,93 @@ h`,
 		})
 	}
 }
+
+func Test_ParseKeyValuePairs(t *testing.T) {
+	testCases := []struct {
+		name        string
+		pairs       []string
+		delimiter   string
+		expected    map[string]any
+		expectedErr error
+	}{
+		{
+			name:      "multiple delimiters",
+			pairs:     []string{"a==b", "c=d=", "e=f"},
+			delimiter: "=",
+			expected: map[string]any{
+				"a": "=b",
+				"c": "d=",
+				"e": "f",
+			},
+		},
+		{
+			name:        "no delimiter found",
+			pairs:       []string{"ab"},
+			delimiter:   "=",
+			expectedErr: fmt.Errorf("cannot split \"ab\" into 2 items, got 1 item(s)"),
+		},
+		{
+			name:        "no delimiter found 2x",
+			pairs:       []string{"ab", "cd"},
+			delimiter:   "=",
+			expectedErr: fmt.Errorf("cannot split \"ab\" into 2 items, got 1 item(s); cannot split \"cd\" into 2 items, got 1 item(s)"),
+		},
+		{
+			name:      "empty pairs",
+			pairs:     []string{},
+			delimiter: "=",
+			expected:  map[string]any{},
+		},
+		{
+			name:        "empty pair string",
+			pairs:       []string{""},
+			delimiter:   "=",
+			expectedErr: fmt.Errorf("cannot split \"\" into 2 items, got 1 item(s)"),
+		},
+		{
+			name:      "empty delimiter",
+			pairs:     []string{"a=b", "c=d"},
+			delimiter: "",
+			expected: map[string]any{
+				"a": "=b",
+				"c": "=d",
+			},
+		},
+		{
+			name:      "empty pairs & delimiter",
+			pairs:     []string{},
+			delimiter: "",
+			expected:  map[string]any{},
+		},
+		{
+			name:      "early delimiter",
+			pairs:     []string{"=a=b"},
+			delimiter: "=",
+			expected: map[string]any{
+				"": "a=b",
+			},
+		},
+		{
+			name:      "weird spacing",
+			pairs:     []string{"        a=   b    ", "     c       =  d "},
+			delimiter: "=",
+			expected: map[string]any{
+				"a": "b",
+				"c": "d",
+			},
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			result, err := ParseKeyValuePairs(tc.pairs, tc.delimiter)
+
+			if tc.expectedErr == nil {
+				assert.NoError(t, err)
+				assert.Equal(t, tc.expected, result)
+			} else {
+				assert.EqualError(t, err, tc.expectedErr.Error())
+			}
+		})
+	}
+}
diff --git a/pkg/ottl/ottlfuncs/README.md b/pkg/ottl/ottlfuncs/README.md
index d99125af2868..794d1f411387 100644
--- a/pkg/ottl/ottlfuncs/README.md
+++ b/pkg/ottl/ottlfuncs/README.md
@@ -847,7 +847,7 @@ Examples:
 
 The `ParseKeyValue` Converter returns a `pcommon.Map` that is a result of parsing the target string for key value pairs.
 
-`target` is a Getter that returns a string. `delimiter` is an optional string that is used to split the key and value in a pair, the default is `=`. `pair_delimiter` is an optional string that is used to split key value pairs, the default is a single space (` `).
+`target` is a Getter that returns a string. If the returned string is empty, an error will be returned. `delimiter` is an optional string that is used to split the key and value in a pair, the default is `=`. `pair_delimiter` is an optional string that is used to split key value pairs, the default is a single space (` `).
 
 For example, the following target `"k1=v1 k2=v2 k3=v3"` will use default delimiters and be parsed into the following map:
 ```
diff --git a/pkg/ottl/ottlfuncs/func_parse_key_value.go b/pkg/ottl/ottlfuncs/func_parse_key_value.go
index 71a6c6eab7df..1b896656ebe2 100644
--- a/pkg/ottl/ottlfuncs/func_parse_key_value.go
+++ b/pkg/ottl/ottlfuncs/func_parse_key_value.go
@@ -1,12 +1,11 @@
 // Copyright The OpenTelemetry Authors
 // SPDX-License-Identifier: Apache-2.0
 
-package ottlfuncs
+package ottlfuncs // import "github.com/open-telemetry/opentelemetry-collector-contrib/pkg/ottl/ottlfuncs"
 
 import (
 	"context"
 	"fmt"
-	"strings"
 
 	"go.opentelemetry.io/collector/pdata/pcommon"
 
@@ -70,15 +69,9 @@ func parseKeyValue[K any](target ottl.StringGetter[K], d ottl.Optional[string],
 			return nil, fmt.Errorf("splitting source %q into pairs failed: %w", source, err)
 		}
 
-		parsed := make(map[string]any)
-		for _, p := range pairs {
-			pair := strings.SplitN(p, delimiter, 2)
-			if len(pair) != 2 {
-				return nil, fmt.Errorf("cannot split %q into 2 items, got %d item(s)", p, len(pair))
-			}
-			key := strings.TrimSpace(pair[0])
-			value := strings.TrimSpace(pair[1])
-			parsed[key] = value
+		parsed, err := parseutils.ParseKeyValuePairs(pairs, delimiter)
+		if err != nil {
+			return nil, fmt.Errorf("failed to split pairs into key-values: %w", err)
 		}
 
 		result := pcommon.NewMap()
diff --git a/pkg/ottl/ottlfuncs/func_parse_key_value_test.go b/pkg/ottl/ottlfuncs/func_parse_key_value_test.go
index 77ad9a8c9431..340c29b8300a 100644
--- a/pkg/ottl/ottlfuncs/func_parse_key_value_test.go
+++ b/pkg/ottl/ottlfuncs/func_parse_key_value_test.go
@@ -330,7 +330,7 @@ func Test_parseKeyValue_bad_split(t *testing.T) {
 	exprFunc, err := parseKeyValue[any](target, delimiter, pairDelimiter)
 	assert.NoError(t, err)
 	_, err = exprFunc(context.Background(), nil)
-	assert.ErrorContains(t, err, "cannot split \"hello_world\" into 2 items, got 1 item(s)")
+	assert.ErrorContains(t, err, "failed to split pairs into key-values: cannot split \"hello_world\" into 2 items, got 1 item(s)")
 }
 
 func Test_parseKeyValue_mismatch_quotes(t *testing.T) {
@@ -357,7 +357,7 @@ func Test_parseKeyValue_bad_delimiter(t *testing.T) {
 	exprFunc, err := parseKeyValue[any](target, delimiter, ottl.Optional[string]{})
 	assert.NoError(t, err)
 	_, err = exprFunc(context.Background(), nil)
-	assert.ErrorContains(t, err, "cannot split \"a=b\" into 2 items, got 1 item(s)")
+	assert.ErrorContains(t, err, "failed to split pairs into key-values: cannot split \"a=b\" into 2 items, got 1 item(s)")
 }
 
 func Test_parseKeyValue_empty_delimiters(t *testing.T) {