Add --envrc-dir flag to allow specifying location of direnv config (#2629)

## Summary
Fixes #2459 - devbox generate direnv does not respect --config

It seems that the previous mode of operation for `devbox generate direnv
--config <some-dir>` used `--config` to determine the location of the
resulting `.envrc` file, rather than as the location of the
`devbox.json` file. But in some cases it is desired to be able to
specify not only the location of not only the direnv `.envrc` file, but
also the devbox config file. Or at least to be able to specify just the
location of the devbox config with the `.envrc` being in the current
directory.

To accomplish this, without breaking the current mode of operation, a
new parameter is added, `--envrc-dir`, which specifies the location of
the resulting `.envrc` file. For example, the command `devbox generate
direnv --envrc-dir ABC --config ABC/XYZ` would create `ABC/.envrc` and
within that would be the command `eval "$(devbox generate direnv
--print-envrc --config XYZ)"`

Without the new `--envrc-dir` param, operation is the same as it was
previously.

The output from `--print-envrc` now invokes `devbox shellenv...` prior
to the `watch_file` command. This allows us to use
`$DEVBOX_PROJECT_ROOT` to specify the path to the config and lock files.
This ensures the correct files are being watched.

## How was it tested?
Several new tests have been created to cover cases with and without the
new `--envrc-dir` param.

## Community Contribution License

All community contributions in this pull request are licensed to the
project
maintainers under the terms of the
[Apache 2 License](https://www.apache.org/licenses/LICENSE-2.0).

By creating this pull request, I represent that I have the right to
license the
contributions to the project maintainers under the Apache 2 License as
stated in
the
[Community Contribution
License](https://github.com/jetify-com/opensource/blob/main/CONTRIBUTING.md#community-contribution-license).

---------

Co-authored-by: Mike Landau <mikeland86@gmail.com>

Author: pstephan-geico-external

internal/boxcli/generate.go

@@ -24,6 +24,7 @@ type generateCmdFlags struct {
 	force             bool
 	printEnvrcContent bool
 	rootUser          bool
+	envrcDir          string // only used by generate direnv command
 }
 
 type generateDockerfileCmdFlags struct {
@@ -147,10 +148,22 @@ func direnvCmd() *cobra.Command {
 	command.Flags().BoolVarP(
 		&flags.force, "force", "f", false, "force overwrite existing files")
 	command.Flags().BoolVarP(
-		&flags.printEnvrcContent, "print-envrc", "p", false, "output contents of devbox configuration to use in .envrc")
+		&flags.printEnvrcContent, "print-envrc", "p", false,
+		"output contents of devbox configuration to use in .envrc")
 	// this command marks a flag as hidden. Error handling for it is not necessary.
 	_ = command.Flags().MarkHidden("print-envrc")
 
+	// --envrc-dir allows users to specify a directory where the .envrc file should be generated
+	// separately from the devbox config directory. Without this flag, the .envrc file
+	// will be generated in the same directory as the devbox config file (i.e., either the current
+	// directory or the directory specified by --config). This flag is useful for users who want to
+	// keep their .envrc and devbox config files in different locations.
+	command.Flags().StringVar(
+		&flags.envrcDir, "envrc-dir", "",
+		"path to directory where the .envrc file should be generated.\n"+
+			"If not specified, the .envrc file will be generated in the same directory as\n"+
+			"the devbox.json.")
+
 	flags.config.register(command)
 	return command
 }
@@ -266,9 +279,17 @@ func runGenerateCmd(cmd *cobra.Command, flags *generateCmdFlags) error {
 }
 
 func runGenerateDirenvCmd(cmd *cobra.Command, flags *generateCmdFlags) error {
+	// --print-envrc is used within the .envrc file and therefore doesn't make sense to also
+	// use it with --envrc-dir, which specifies a directory where the .envrc file should be generated.
+	if flags.printEnvrcContent && flags.envrcDir != "" {
+		return usererr.New(
+			"Cannot use --print-envrc with --envrc-dir. " +
+				"Use --envrc-dir to specify the directory where the .envrc file should be generated.")
+	}
+
 	if flags.printEnvrcContent {
 		return devbox.PrintEnvrcContent(
-			cmd.OutOrStdout(), devopt.EnvFlags(flags.envFlag))
+			cmd.OutOrStdout(), devopt.EnvFlags(flags.envFlag), flags.config.path)
 	}
 
 	box, err := devbox.Open(&devopt.Opts{
@@ -280,6 +301,12 @@ func runGenerateDirenvCmd(cmd *cobra.Command, flags *generateCmdFlags) error {
 		return errors.WithStack(err)
 	}
 
-	return box.GenerateEnvrcFile(
-		cmd.Context(), flags.force, devopt.EnvFlags(flags.envFlag))
+	generateEnvrcOpts := devopt.EnvrcOpts{
+		EnvFlags:  devopt.EnvFlags(flags.envFlag),
+		Force:     flags.force,
+		EnvrcDir:  flags.envrcDir,
+		ConfigDir: flags.config.path,
+	}
+
+	return box.GenerateEnvrcFile(cmd.Context(), generateEnvrcOpts)
 }

internal/devbox/devbox.go

@@ -527,21 +527,28 @@ func (d *Devbox) GenerateDockerfile(ctx context.Context, generateOpts devopt.Gen
 	}))
 }
 
-func PrintEnvrcContent(w io.Writer, envFlags devopt.EnvFlags) error {
-	return generate.EnvrcContent(w, envFlags)
+func PrintEnvrcContent(w io.Writer, envFlags devopt.EnvFlags, configDir string) error {
+	return generate.EnvrcContent(w, envFlags, configDir)
 }
 
 // GenerateEnvrcFile generates a .envrc file that makes direnv integration convenient
-func (d *Devbox) GenerateEnvrcFile(ctx context.Context, force bool, envFlags devopt.EnvFlags) error {
+func (d *Devbox) GenerateEnvrcFile(ctx context.Context, opts devopt.EnvrcOpts) error {
 	ctx, task := trace.NewTask(ctx, "devboxGenerateEnvrc")
 	defer task.End()
 
-	envrcfilePath := filepath.Join(d.projectDir, ".envrc")
-	filesExist := fileutil.Exists(envrcfilePath)
-	if !force && filesExist {
+	// If no envrcDir was specified, use the configDir. This is for backward compatibility
+	// where the .envrc was placed in the same location as specified by --config. Note that
+	// if that is also blank, the .envrc will be generated in the current working directory.
+	if opts.EnvrcDir == "" {
+		opts.EnvrcDir = opts.ConfigDir
+	}
+
+	envrcFilePath := filepath.Join(opts.EnvrcDir, ".envrc")
+	filesExist := fileutil.Exists(envrcFilePath)
+	if !opts.Force && filesExist {
 		return usererr.New(
-			"A .envrc is already present in the current directory. " +
-				"Remove it or use --force to overwrite it.",
+			"A .envrc is already present in %q. Remove it or use --force to overwrite it.",
+			opts.EnvrcDir,
 		)
 	}
 
@@ -551,18 +558,18 @@ func (d *Devbox) GenerateEnvrcFile(ctx context.Context, force bool, envFlags dev
 	}
 
 	// .envrc file creation
-	err := generate.CreateEnvrc(ctx, d.projectDir, envFlags)
+	err := generate.CreateEnvrc(ctx, opts)
 	if err != nil {
 		return errors.WithStack(err)
 	}
-	ux.Fsuccessf(d.stderr, "generated .envrc file\n")
+	ux.Fsuccessf(d.stderr, "generated .envrc file in %q.\n", opts.EnvrcDir)
 	if cmdutil.Exists("direnv") {
-		cmd := exec.Command("direnv", "allow")
+		cmd := exec.Command("direnv", "allow", opts.EnvrcDir)
 		err := cmd.Run()
 		if err != nil {
 			return errors.WithStack(err)
 		}
-		ux.Fsuccessf(d.stderr, "ran `direnv allow`\n")
+		ux.Fsuccessf(d.stderr, "ran `direnv allow %s`\n", opts.EnvrcDir)
 	}
 	return nil
 }

internal/devbox/devopt/devboxopts.go

@@ -34,6 +34,13 @@ type EnvFlags struct {
 	EnvFile string
 }
 
+type EnvrcOpts struct {
+	EnvFlags
+	Force     bool
+	EnvrcDir  string
+	ConfigDir string
+}
+
 type PullboxOpts struct {
 	Overwrite   bool
 	URL         string

internal/devbox/generate/devcontainer_util.go

@@ -140,35 +140,68 @@ func (g *Options) CreateDevcontainer(ctx context.Context) error {
 	return err
 }
 
-func CreateEnvrc(ctx context.Context, path string, envFlags devopt.EnvFlags) error {
+func CreateEnvrc(ctx context.Context, opts devopt.EnvrcOpts) error {
 	defer trace.StartRegion(ctx, "createEnvrc").End()
 
 	// create .envrc file
-	file, err := os.Create(filepath.Join(path, ".envrc"))
+	file, err := os.Create(filepath.Join(opts.EnvrcDir, ".envrc"))
 	if err != nil {
 		return err
 	}
 	defer file.Close()
 
 	flags := []string{}
 
-	if len(envFlags.EnvMap) > 0 {
-		for k, v := range envFlags.EnvMap {
+	if len(opts.EnvMap) > 0 {
+		for k, v := range opts.EnvMap {
 			flags = append(flags, fmt.Sprintf("--env %s=%s", k, v))
 		}
 	}
-	if envFlags.EnvFile != "" {
-		flags = append(flags, fmt.Sprintf("--env-file %s", envFlags.EnvFile))
+	if opts.EnvFile != "" {
+		flags = append(flags, fmt.Sprintf("--env-file %s", opts.EnvFile))
+	}
+
+	configDir, err := getRelativePathToConfig(opts.EnvrcDir, opts.ConfigDir)
+	if err != nil {
+		return err
 	}
 
 	t := template.Must(template.ParseFS(tmplFS, "tmpl/envrc.tmpl"))
 
 	// write content into file
 	return t.Execute(file, map[string]string{
-		"Flags": strings.Join(flags, " "),
+		"EnvFlag":   strings.Join(flags, " "),
+		"ConfigDir": formatConfigDirArg(configDir),
 	})
 }
 
+// Returns the relative path from sourceDir to configDir, or an error if it cannot be determined.
+func getRelativePathToConfig(sourceDir, configDir string) (string, error) {
+	absConfigDir, err := filepath.Abs(configDir)
+	if err != nil {
+		return "", fmt.Errorf("failed to get absolute path for config dir: %w", err)
+	}
+
+	absSourceDir, err := filepath.Abs(sourceDir)
+	if err != nil {
+		return "", fmt.Errorf("failed to get absolute path for source dir: %w", err)
+	}
+
+	// We don't want the path if the config dir is a parent of the envrc dir. This way
+	// the config will be found when it recursively searches for it through the parent tree.
+	if strings.HasPrefix(absSourceDir, absConfigDir) {
+		return "", nil
+	}
+
+	relPath, err := filepath.Rel(absSourceDir, absConfigDir)
+	if err != nil {
+		// If a relative path cannot be computed, return the absolute path of configDir
+		return absConfigDir, err
+	}
+
+	return relPath, nil
+}
+
 func (g *Options) getDevcontainerContent() *devcontainerObject {
 	// object that gets written in devcontainer.json
 	devcontainerContent := &devcontainerObject{
@@ -219,17 +252,26 @@ func (g *Options) getDevcontainerContent() *devcontainerObject {
 	return devcontainerContent
 }
 
-func EnvrcContent(w io.Writer, envFlags devopt.EnvFlags) error {
-	tmplName := "envrcContent.tmpl"
-	t := template.Must(template.ParseFS(tmplFS, "tmpl/"+tmplName))
+func EnvrcContent(w io.Writer, envFlags devopt.EnvFlags, configDir string) error {
+	t := template.Must(template.ParseFS(tmplFS, "tmpl/envrcContent.tmpl"))
 	envFlag := ""
 	if len(envFlags.EnvMap) > 0 {
 		for k, v := range envFlags.EnvMap {
 			envFlag += fmt.Sprintf("--env %s=%s ", k, v)
 		}
 	}
+
 	return t.Execute(w, map[string]string{
-		"EnvFlag": envFlag,
-		"EnvFile": envFlags.EnvFile,
+		"EnvFlag":   envFlag,
+		"EnvFile":   envFlags.EnvFile,
+		"ConfigDir": formatConfigDirArg(configDir),
 	})
 }
+
+func formatConfigDirArg(configDir string) string {
+	if configDir == "" {
+		return ""
+	}
+
+	return "--config " + configDir
+}

internal/devbox/generate/tmpl/envrc.tmpl

@@ -3,7 +3,7 @@
 # Automatically sets up your devbox environment whenever you cd into this
 # directory via our direnv integration:
 
-eval "$(devbox generate direnv --print-envrc{{ if .Flags}} {{ .Flags }}{{ end }})"
+eval "$(devbox generate direnv --print-envrc{{ if .EnvFlag}} {{ .EnvFlag }}{{ end }}{{ if .ConfigDir }} {{ .ConfigDir }}{{ end }})"
 
 # check out https://www.jetify.com/docs/devbox/ide_configuration/direnv/
 # for more details

internal/devbox/generate/tmpl/envrcContent.tmpl

@@ -1,6 +1,6 @@
 use_devbox() {
-    watch_file devbox.json devbox.lock
-    eval "$(devbox shellenv --init-hook --install --no-refresh-alias{{ if .EnvFlag }} {{ .EnvFlag }}{{ end }})"
+    eval "$(devbox shellenv --init-hook --install --no-refresh-alias{{ if .EnvFlag }} {{ .EnvFlag }}{{ end }}{{ if .ConfigDir }} {{ .ConfigDir }}{{ end }})"
+    watch_file $DEVBOX_PROJECT_ROOT/devbox.json $DEVBOX_PROJECT_ROOT/devbox.lock
 }
 use devbox
 {{ if .EnvFile }}

testscripts/generate/direnv-config-envflag.test.txt

@@ -0,0 +1,26 @@
+# Testscript to validate generating the contents of the .envrc file.
+# Note that since --envrc-dir was NOT specified, the .envrc will be in the `dir` directory and
+# the config will be found there, which means the `--print-env` doesn't need to specify the dir.
+# This matches the mode of operation prior to the addition of the --envrc-dir flag.
+
+mkdir dir
+exec devbox init dir
+exists dir/devbox.json
+
+exec devbox generate direnv --env x=y --config dir
+grep 'eval "\$\(devbox generate direnv --print-envrc --env x=y\)"' dir/.envrc
+
+cd dir
+exec devbox generate direnv --print-envrc --env x=y
+
+cmp stdout ../expected-results.txt
+
+# Note: The contents of the following file ends with two blank lines. This is
+# necessary to match the blank line that follows "use devbox" in the actual output.
+-- expected-results.txt --
+use_devbox() {
+    eval "$(devbox shellenv --init-hook --install --no-refresh-alias --env x=y )"
+    watch_file $DEVBOX_PROJECT_ROOT/devbox.json $DEVBOX_PROJECT_ROOT/devbox.lock
+}
+use devbox
+

testscripts/generate/direnv-config.test.txt

@@ -0,0 +1,26 @@
+# Testscript to validate generating the contents of the .envrc file.
+# Note that since --envrc-dir was NOT specified, the .envrc will be in the `dir` directory and
+# the config will be found there, which means the `--print-env` doesn't need to specify the dir.
+# This matches the mode of operation prior to the addition of the --envrc-dir flag.
+
+mkdir dir
+exec devbox init dir
+exists dir/devbox.json
+
+exec devbox generate direnv --config dir
+grep 'eval "\$\(devbox generate direnv --print-envrc\)"' dir/.envrc
+
+cd dir
+exec devbox generate direnv --print-envrc
+
+cmp stdout ../expected-results.txt
+
+# Note: The contents of the following file ends with two blank lines. This is
+# necessary to match the blank line that follows "use devbox" in the actual output.
+-- expected-results.txt --
+use_devbox() {
+    eval "$(devbox shellenv --init-hook --install --no-refresh-alias)"
+    watch_file $DEVBOX_PROJECT_ROOT/devbox.json $DEVBOX_PROJECT_ROOT/devbox.lock
+}
+use devbox
+

testscripts/generate/direnv-envflag.test.txt

@@ -0,0 +1,21 @@
+# Testscript to validate generating the contents of the .envrc file.
+
+exec devbox init
+exists devbox.json
+
+exec devbox generate direnv --env x=y
+grep 'eval "\$\(devbox generate direnv --print-envrc --env x=y\)"' .envrc
+
+exec devbox generate direnv --print-envrc --env x=y
+
+cmp stdout expected-results.txt
+
+# Note: The contents of the following file ends with two blank lines. This is
+# necessary to match the blank line that follows "use devbox" in the actual output.
+-- expected-results.txt --
+use_devbox() {
+    eval "$(devbox shellenv --init-hook --install --no-refresh-alias --env x=y )"
+    watch_file $DEVBOX_PROJECT_ROOT/devbox.json $DEVBOX_PROJECT_ROOT/devbox.lock
+}
+use devbox
+

testscripts/generate/direnv-envrcdir-config-parent.test.txt

@@ -0,0 +1,27 @@
+# Testscript to validate generating a direnv .envrc in a specified location (./dir).
+# The devbox config is in the current dir (parent to ./dir). Since no --config
+# is specified, the normal config-finding will find the config.
+
+exec devbox init
+exists ./devbox.json
+
+mkdir dir
+
+exec devbox generate direnv --envrc-dir dir
+grep 'eval "\$\(devbox generate direnv --print-envrc\)"' dir/.envrc
+! grep '--config' dir/.envrc # redundant, but making expectations obvious
+
+cd dir
+exec devbox generate direnv --print-envrc
+
+cmp stdout ../expected-results.txt
+
+# Note: The contents of the following file ends with two blank lines. This is
+# necessary to match the blank line that follows "use devbox" in the actual output.
+-- expected-results.txt --
+use_devbox() {
+    eval "$(devbox shellenv --init-hook --install --no-refresh-alias)"
+    watch_file $DEVBOX_PROJECT_ROOT/devbox.json $DEVBOX_PROJECT_ROOT/devbox.lock
+}
+use devbox
+