Allow an ENV var for APPPACK_TOML to specify the path to the toml file. See Issue #10

CHANGELOG.md

@@ -10,3 +10,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Fixed
 
 * Release tasks work with latest metadata from Heroku Buildpacks
+
+## [2.2.0] - 2025-09-19
+
+### Added
+
+* apppack.toml file is now accessible by APPPACK_TOML environment variable, allowing different services in different environments. 

builder/build/apppacktoml.go

@@ -6,6 +6,7 @@ import (
 	"os"
 	"strings"
 
+	"github.com/apppackio/codebuild-image/builder/filesystem"
 	"github.com/BurntSushi/toml"
 	"github.com/rs/zerolog/log"
 )
@@ -103,19 +104,21 @@ func (a *AppPackToml) GetTestEnv() map[string]string {
 func ParseAppPackToml(ctx context.Context) (*AppPackToml, error) {
 	var config AppPackToml
 	// if the file doesn't exist, just return an empty config
-	if _, err := os.Stat("apppack.toml"); os.IsNotExist(err) {
-		log.Ctx(ctx).Debug().Msg("apppack.toml not found")
+	filename := filesystem.GetAppPackTomlFilename()
+	if _, err := os.Stat(filename); os.IsNotExist(err) {
+		log.Ctx(ctx).Debug().Msg(fmt.Sprintf("%s not found", filename))
 		return &config, nil
 	}
-	if _, err := toml.DecodeFile("apppack.toml", &config); err != nil {
+	if _, err := toml.DecodeFile(filename, &config); err != nil {
 		return nil, err
 	}
 	return &config, nil
 }
 
 func (a AppPackToml) Write(ctx context.Context) error {
-	log.Ctx(ctx).Debug().Msg("writing apppack.toml")
-	f, err := os.Create("apppack.toml")
+	filename := filesystem.GetAppPackTomlFilename()
+	log.Ctx(ctx).Debug().Msg(fmt.Sprintf("writing %s", filename))
+	f, err := os.Create(filename)
 	if err != nil {
 		return err
 	}

builder/build/prebuild.go

@@ -148,15 +148,16 @@ func (b *Build) ConvertAppJson() error {
 		return err
 	}
 	// check if apppack.toml file exists
-	apppackTomlExists, err := b.state.FileExists("apppack.toml")
+	filename := filesystem.GetAppPackTomlFilename()
+	apppackTomlExists, err := b.state.FileExists(filename)
 	if err != nil {
 		return err
 	}
 	if appJsonExists && !apppackTomlExists {
 		// convert app.json to apppack.toml
-		b.Log().Info().Msg("Converting app.json to apppack.toml")
+		b.Log().Info().Msg(fmt.Sprintf("Converting app.json to %s", filename))
 		t := b.AppJSON.ToApppackToml()
-		return b.state.WriteTomlToFile("apppack.toml", t)
+		return b.state.WriteTomlToFile(filename, t)
 	}
 	return nil
 }

builder/filesystem/filesystem.go

@@ -58,7 +58,9 @@ func (f *FileState) Log() *zerolog.Logger {
 
 func (f *FileState) CreateIfNotExists() error {
 	// touch files codebuild expects to exist
-	for _, filename := range []string{"apppack.toml", "build.log", "metadata.toml", "test.log"} {
+	apppackToml := GetAppPackTomlFilename()
+
+	for _, filename := range []string{apppackToml, "build.log", "metadata.toml", "test.log"} {
 		exists, err := f.FileExists(filename)
 		if err != nil {
 			return err
@@ -177,3 +179,11 @@ func (f *FileState) WriteJsonToFile(filename string, v interface{}) error {
 	}
 	return nil
 }
+
+func GetAppPackTomlFilename() string {
+	filename := "apppack.toml"
+	if envFile := os.Getenv("APPPACK_TOML"); envFile != "" {
+		filename = envFile
+	}
+	return filename
+}

builder/filesystem/filesystem_test.go

@@ -4,6 +4,7 @@ import (
 	"archive/tar"
 	"bytes"
 	"context"
+	"fmt"
 	"io"
 	"os"
 	"testing"
@@ -16,8 +17,11 @@ var testContext = zerolog.New(os.Stdout).With().Timestamp().Logger().WithContext
 
 func TestCreateIfNotExists(t *testing.T) {
 	fs := afero.Afero{Fs: afero.NewMemMapFs()}
-	if _, err := fs.Stat("apppack.toml"); !os.IsNotExist(err) {
-		t.Error("apppack.toml should not exist")
+
+	filename := GetAppPackTomlFilename()
+
+	if _, err := fs.Stat(filename); !os.IsNotExist(err) {
+		t.Error(fmt.Sprintf("%s should not exist", filename))
 	}
 	s := &FileState{
 		fs:  fs,
@@ -27,8 +31,8 @@ func TestCreateIfNotExists(t *testing.T) {
 	if err != nil {
 		t.Error(err)
 	}
-	if _, err := fs.Stat("apppack.toml"); os.IsNotExist(err) {
-		t.Error("apppack.toml should exist")
+	if _, err := fs.Stat(filename); os.IsNotExist(err) {
+		t.Error(fmt.Sprintf("%s should exist", filename))
 	}
 }
 
@@ -105,6 +109,27 @@ func TestWriteEnvFile(t *testing.T) {
 	}
 }
 
+func TestGetFilename(t *testing.T) {
+	// Check that there is no env variable set
+	if os.Getenv("APPPACK_TOML") != "" {
+		t.Error("APPPACK_TOML env variable should not be set")
+	}
+	// Call GetAppPackTomlFilename and check the default value
+
+	filename := GetAppPackTomlFilename()
+	if filename != "apppack.toml" {
+		t.Errorf("expected apppack.toml, got %s", filename)
+	}
+
+	// Set the env variable and check again
+	os.Setenv("APPPACK_TOML", "custom.toml")
+	defer os.Unsetenv("APPPACK_TOML") // Clean up after the test
+	filename = GetAppPackTomlFilename()
+	if filename != "custom.toml" {
+		t.Errorf("expected custom.toml, got %s", filename)
+	}
+}
+
 func dummyTarBuffer() (*io.Reader, error) {
 	var buf bytes.Buffer
 	tw := tar.NewWriter(&buf)