disallow unknown fields (#98)

* disallow unknown fields

* test ci

dump.go

@@ -4,6 +4,7 @@ import (
 	"bytes"
 	"encoding/json"
 	"errors"
+	"io"
 	"strings"
 
 	"gopkg.in/yaml.v3"
@@ -23,15 +24,44 @@ func ParseAs(raw string, format Format) (Config, error) {
 	var out Config
 	switch strings.ToLower(string(format)) {
 	case "", "ini", "conf", "classic":
-		return out, out.UnmarshalClassic([]byte(raw))
+		return ParseAsClassic(raw)
 	case "yml", "yaml":
-		return out, yaml.Unmarshal([]byte(raw), &out)
+		return ParseAsYAML(raw)
 	case "json":
-		return out, json.Unmarshal([]byte(raw), &out)
+		return ParseAsJSON(raw)
 	}
 	return out, ErrFormatUnknown
 }
 
+func ParseAsClassic(raw string) (Config, error) {
+	var out Config
+	return out, out.UnmarshalClassic([]byte(raw))
+}
+
+func ParseAsYAML(raw string) (Config, error) {
+	var out Config
+	dec := yaml.NewDecoder(strings.NewReader(raw))
+	dec.KnownFields(true)
+	err := dec.Decode(&out)
+	if errors.Is(err, io.EOF) {
+		return out, nil
+	}
+
+	return out, err
+}
+
+func ParseAsJSON(raw string) (Config, error) {
+	var out Config
+	dec := json.NewDecoder(strings.NewReader(raw))
+	dec.DisallowUnknownFields()
+	err := dec.Decode(&out)
+	if errors.Is(err, io.EOF) {
+		return out, nil
+	}
+
+	return out, err
+}
+
 func (c Config) DumpAs(format Format) (string, error) {
 	switch strings.ToLower(string(format)) {
 	case "", "ini", "conf", "classic":

dump_test.go

@@ -0,0 +1,80 @@
+package fluentbitconfig
+
+import (
+	"fmt"
+	"strings"
+	"testing"
+
+	"github.com/alecthomas/assert/v2"
+	"github.com/muesli/reflow/dedent"
+
+	"github.com/calyptia/go-fluentbit-config/v2/property"
+)
+
+func TestParseAsYAML(t *testing.T) {
+	t.Run("unknown_plural_pipelines", func(t *testing.T) {
+		_, err := ParseAsYAML(configLiteral(`
+			pipelines:
+				inputs:
+					- name: dummy
+		`))
+		assert.EqualError(t, err, "yaml: unmarshal errors:\n  line 1: field pipelines not found in type fluentbitconfig.Config")
+	})
+
+	t.Run("unknown_section", func(t *testing.T) {
+		_, err := ParseAsYAML(configLiteral(`
+			unknown:
+				- name: dummy
+		`))
+		assert.EqualError(t, err, "yaml: unmarshal errors:\n  line 1: field unknown not found in type fluentbitconfig.Config")
+	})
+
+	t.Run("unknown_pipeline_plugins_kind", func(t *testing.T) {
+		_, err := ParseAsYAML(configLiteral(`
+			pipeline:
+				foos:
+					- name: bar
+		`))
+		assert.EqualError(t, err, "yaml: unmarshal errors:\n  line 2: field foos not found in type fluentbitconfig.Pipeline")
+	})
+
+	t.Run("empty", func(t *testing.T) {
+		got, err := ParseAsYAML("")
+		assert.NoError(t, err)
+		assert.Equal(t, Config{}, got)
+	})
+
+	t.Run("ok", func(t *testing.T) {
+		text := configLiteral(`
+			pipeline:
+				inputs:
+					- name: dummy
+		`)
+		fmt.Printf("text: %q\n", text)
+		cfg, err := ParseAsYAML(text)
+		assert.NoError(t, err)
+		assert.Equal(t, Config{
+			Pipeline: Pipeline{
+				Inputs: []Plugin{
+					{
+						ID:   "dummy.0",
+						Name: "dummy",
+						Properties: property.Properties{
+							{
+								Key:   "name",
+								Value: "dummy",
+							},
+						},
+					},
+				},
+			},
+		}, cfg)
+	})
+}
+
+func configLiteral(s string) string {
+	if strings.HasPrefix(s, "\n\t") {
+		s = dedent.String(s)
+	}
+	return strings.TrimSpace(strings.ReplaceAll(s, "\t", "    ")) + "\n"
+}

go.mod

@@ -4,7 +4,8 @@ go 1.22.4
 
 require (
 	github.com/alecthomas/assert/v2 v2.10.0
-	golang.org/x/exp v0.0.0-20240604190554-fc45aab8b7f8
+	github.com/muesli/reflow v0.3.0
+	golang.org/x/exp v0.0.0-20240613232115-7f521ea00fb8
 	gopkg.in/yaml.v3 v3.0.1
 )
 

go.sum

@@ -4,9 +4,13 @@ github.com/alecthomas/repr v0.4.0 h1:GhI2A8MACjfegCPVq9f1FLvIBS+DrQ2KQBFZP1iFzXc
 github.com/alecthomas/repr v0.4.0/go.mod h1:Fr0507jx4eOXV7AlPV6AVZLYrLIuIeSOWtW57eE/O/4=
 github.com/hexops/gotextdiff v1.0.3 h1:gitA9+qJrrTCsiCl7+kh75nPqQt1cx4ZkudSTLoUqJM=
 github.com/hexops/gotextdiff v1.0.3/go.mod h1:pSWU5MAI3yDq+fZBTazCSJysOMbxWL1BSow5/V2vxeg=
-golang.org/x/exp v0.0.0-20240604190554-fc45aab8b7f8 h1:LoYXNGAShUG3m/ehNk4iFctuhGX/+R1ZpfJ4/ia80JM=
-golang.org/x/exp v0.0.0-20240604190554-fc45aab8b7f8/go.mod h1:jj3sYF3dwk5D+ghuXyeI3r5MFf+NT2An6/9dOA95KSI=
-gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
+github.com/mattn/go-runewidth v0.0.12/go.mod h1:RAqKPSqVFrSLVXbA8x7dzmKdmGzieGRCM46jaSJTDAk=
+github.com/muesli/reflow v0.3.0 h1:IFsN6K9NfGtjeggFP+68I4chLZV2yIKsXJFNZ+eWh6s=
+github.com/muesli/reflow v0.3.0/go.mod h1:pbwTDkVPibjO2kyvBQRBxTWEEGDGq0FlB1BIKtnHY/8=
+github.com/rivo/uniseg v0.1.0/go.mod h1:J6wj4VEh+S6ZtnVlnTBMWIodfgj8LQOQFoIToxlJtxc=
+github.com/rivo/uniseg v0.2.0/go.mod h1:J6wj4VEh+S6ZtnVlnTBMWIodfgj8LQOQFoIToxlJtxc=
+golang.org/x/exp v0.0.0-20240613232115-7f521ea00fb8 h1:yixxcjnhBmY0nkL253HFVIm0JsFHwrHdT3Yh6szTnfY=
+golang.org/x/exp v0.0.0-20240613232115-7f521ea00fb8/go.mod h1:jj3sYF3dwk5D+ghuXyeI3r5MFf+NT2An6/9dOA95KSI=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
 gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=