feat: add writer step

6_writer/write.go

@@ -0,0 +1,43 @@
+package writer
+
+import (
+	"bytes"
+	"io"
+	"os"
+	"path"
+
+	"github.com/pkg/errors"
+)
+
+func Write(src []byte, templateFile string) (int64, error) {
+	cwd, err := os.Getwd()
+
+	if err != nil {
+		return 0, errors.WithStack(err)
+	}
+
+	var writer io.Writer
+
+	if templateFile != "" {
+		if !path.IsAbs(templateFile) {
+			templateFile = path.Join(cwd, templateFile)
+		}
+		file, err := os.Create(templateFile)
+
+		if err != nil {
+			return 0, errors.WithStack(err)
+		}
+
+		writer = file
+	} else {
+		writer = os.Stdout
+	}
+
+	n, err := io.Copy(writer, bytes.NewBuffer(src))
+
+	if err != nil {
+		return n, errors.WithStack(err)
+	}
+
+	return n, nil
+}

HOW_IT_WORKS.md

@@ -54,4 +54,8 @@ Up to this point, the role of generator is to generate templates and which templ
 
 ### 5. formatter
 
-In this step we will format the output. For example, format markdown/json
+In this step we will format the output. For example, format markdown/json
+
+### 6. writer
+
+Output content at this stage, it determines whether to output a file or stdout

main.go

@@ -1,18 +1,16 @@
 package main
 
 import (
-	"bytes"
 	"flag"
 	"fmt"
-	"io"
 	"os"
-	"path"
 
 	parser "github.com/axetroy/changelog/1_parser"
 	extractor "github.com/axetroy/changelog/2_extractor"
 	transform "github.com/axetroy/changelog/3_transform"
 	generator "github.com/axetroy/changelog/4_generator"
 	formatter "github.com/axetroy/changelog/5_formatter"
+	writer "github.com/axetroy/changelog/6_writer"
 	"github.com/axetroy/changelog/internal/client"
 	"github.com/pkg/errors"
 )
@@ -154,30 +152,13 @@ func run() error {
 		return errors.WithStack(err)
 	}
 
-	var writer io.Writer
-
-	if outputFile != "" {
-		if !path.IsAbs(outputFile) {
-			outputFile = path.Join(cwd, outputFile)
-		}
-		file, err := os.Create(outputFile)
-
-		if err != nil {
-			return errors.WithStack(err)
-		}
-
-		writer = file
-	} else {
-		writer = os.Stdout
-	}
-
-	output, err = formatter.Format(output, format, templateFile)
+	formattedOutput, err := formatter.Format(output, format, templateFile)
 
 	if err != nil {
 		return errors.WithStack(err)
 	}
 
-	_, err = io.Copy(writer, bytes.NewBuffer(output))
+	_, err = writer.Write(formattedOutput, outputFile)
 
 	if err != nil {
 		return errors.WithStack(err)