Misc Changes

Makefile

@@ -0,0 +1,26 @@
+GOOS?=linux
+GOARCH?=amd64
+SOURCES:=$(shell find -type f -name '*.go')
+
+PROGRAM:=journald-cloudwatch-logs
+
+.PHONY: all
+all: $(PROGRAM) $(PROGRAM).digests
+
+.PHONY: deps
+deps:
+	go get
+
+$(PROGRAM): $(SOURCES) deps
+	GOOS=$(GOOS) GOARCH=$(GOARCH) go build -o $@
+
+$(PROGRAM).digests: $(PROGRAM)
+	sha256sum $< > $@
+
+.PHONY: install
+install: build
+	go install
+
+.PHONY: clean
+clean:
+	-rm $(PROGRAM)

config.go

@@ -153,7 +153,6 @@ func (c *Config) NewAWSSession() *awsSession.Session {
 	return awsSession.New(config)
 }
 
-
 /*
  * Expand variables of the form $Foo or ${Foo} in the user provided config
  * from the EC2Metadata Instance Identity Document
@@ -167,12 +166,12 @@ func expandFileConfig(config *fileConfig, metaClient *ec2metadata.EC2Metadata) {
 	// struct extracting the string fields and their values into the vars map
 	data, err := metaClient.GetInstanceIdentityDocument()
 	if err == nil {
-		metadata := reflect.ValueOf( data )
+		metadata := reflect.ValueOf(data)
 
 		for i := 0; i < metadata.NumField(); i++ {
 			field := metadata.Field(i)
 			ftype := metadata.Type().Field(i)
-			if (field.Type() != reflect.TypeOf("")) {
+			if field.Type() != reflect.TypeOf("") {
 				continue
 			}
 			vars[ftype.Name] = fmt.Sprintf("%v", field.Interface())
@@ -199,8 +198,8 @@ func expandFileConfig(config *fileConfig, metaClient *ec2metadata.EC2Metadata) {
 								return val
 							}
 							// Unknown key => empty string
-							return "" 
-						} else if (strings.HasPrefix(varname, "env.")) {
+							return ""
+						} else if strings.HasPrefix(varname, "env.") {
 							return os.Getenv(strings.TrimPrefix(varname, "env."))
 						} else {
 							// Unknown prefix => empty string
@@ -213,7 +212,6 @@ func expandFileConfig(config *fileConfig, metaClient *ec2metadata.EC2Metadata) {
 	}
 }
 
-
 // Modified version of os.Expand() that only expands ${name} and not $name
 func expandBraceVars(s string, mapping func(string) string) string {
 	buf := make([]byte, 0, 2*len(s))
@@ -223,10 +221,10 @@ func expandBraceVars(s string, mapping func(string) string) string {
 		if s[j] == '$' && j+3 < len(s) && s[j+1] == '{' {
 			buf = append(buf, s[i:j]...)
 			idx := strings.Index(s[j+2:], "}")
-			if (idx >= 0) {
+			if idx >= 0 {
 				// We have a full ${name} string
 				buf = append(buf, mapping(s[j+2:j+2+idx])...)
-				j += 2+idx
+				j += 2 + idx
 			} else {
 				// We ran out of string (unclosed ${)
 				return string(buf)
@@ -236,6 +234,3 @@ func expandBraceVars(s string, mapping func(string) string) string {
 	}
 	return string(buf) + s[i:]
 }
-
-
-

writer.go

@@ -61,6 +61,14 @@ func (w *Writer) WriteBatch(records []Record) (string, error) {
 		return nil
 	}
 
+	createGroup := func() error {
+		request := &cloudwatchlogs.CreateLogGroupInput{
+			LogGroupName: &w.logGroupName,
+		}
+		_, err := w.conn.CreateLogGroup(request)
+		return err
+	}
+
 	createStream := func() error {
 		request := &cloudwatchlogs.CreateLogStreamInput{
 			LogGroupName:  &w.logGroupName,
@@ -74,10 +82,18 @@ func (w *Writer) WriteBatch(records []Record) (string, error) {
 	if err != nil {
 		if awsErr, ok := err.(awserr.Error); ok {
 			if awsErr.Code() == "ResourceNotFoundException" {
-				// Maybe our log stream doesn't exist yet. We'll try
-				// to create it and then, if we're successful, try
-				// writing the events again.
-				err := createStream()
+				// Maybe our log group or stream doesn't exist
+				// yet. We'll try to create it and then, if we're
+				// successful, try writing the events again.
+				err := createGroup()
+				if err != nil {
+					if awsErr, ok := err.(awserr.Error); ok {
+						if awsErr.Code() != "ResourceAlreadyExistsException" {
+							return "", fmt.Errorf("Failed to create stream: %s", err)
+						}
+					}
+				}
+				err = createStream()
 				if err != nil {
 					return "", fmt.Errorf("failed to create stream: %s", err)
 				}