[refactor] Move config to own package. Don't warn if overwriting defa… (#1045)

## Summary

Stacked on #1043

This is mostly a straight refactor. Just moved everything to new
package, renamed a few methods/constants if it made sense.

Only added functionality is `isModifiedConfig` in pullbox that doesn't
return error if config that is being overwritten is a default config.
(we need this because configs are created automatically so we always get
the prompt even if it's empty)

## How was it tested?

Ran `devbox global pull https://fleekgen.fly.dev/high` with global
directory:

* Empty
* Only with unmodified config
* Only with modified config
* With other files.

Author: mikeland73

devbox.go

@@ -8,6 +8,7 @@ import (
 	"context"
 	"io"
 
+	"go.jetpack.io/devbox/internal/devconfig"
 	"go.jetpack.io/devbox/internal/impl"
 	"go.jetpack.io/devbox/internal/planner/plansdk"
 	"go.jetpack.io/devbox/internal/services"
@@ -19,7 +20,7 @@ type Devbox interface {
 	// environment. It validates that the Nix packages exist, and install them.
 	// Adding duplicate packages is a no-op.
 	Add(ctx context.Context, pkgs ...string) error
-	Config() *impl.Config
+	Config() *devconfig.Config
 	ProjectDir() string
 	// Generate creates the directory of Nix files and the Dockerfile that define
 	// the devbox environment.
@@ -60,7 +61,7 @@ func Open(dir string, writer io.Writer) (Devbox, error) {
 
 // InitConfig creates a default devbox config file if one doesn't already exist.
 func InitConfig(dir string, writer io.Writer) (bool, error) {
-	return impl.InitConfig(dir, writer)
+	return devconfig.Init(dir, writer)
 }
 
 func GlobalDataPath() (string, error) {

internal/boxcli/global.go

@@ -112,9 +112,10 @@ func pullGlobalCmdFunc(
 		if err = survey.AskOne(prompt, &overwrite); err != nil {
 			return errors.WithStack(err)
 		}
-		if overwrite {
-			err = box.PullGlobal(cmd.Context(), overwrite, args[0])
+		if !overwrite {
+			return nil
 		}
+		err = box.PullGlobal(cmd.Context(), overwrite, args[0])
 	}
 	if err != nil {
 		return err

internal/impl/config.go renamed to internal/devconfig/config.go

@@ -1,13 +1,12 @@
 // Copyright 2023 Jetpack Technologies Inc and contributors. All rights reserved.
 // Use of this source code is governed by the license in the LICENSE file.
 
-package impl
+package devconfig
 
 import (
 	"io"
 	"net/http"
 	"net/url"
-	"os"
 	"path/filepath"
 	"regexp"
 	"strings"
@@ -16,12 +15,12 @@ import (
 
 	"go.jetpack.io/devbox/internal/boxcli/usererr"
 	"go.jetpack.io/devbox/internal/cuecfg"
-	"go.jetpack.io/devbox/internal/debug"
-	"go.jetpack.io/devbox/internal/fileutil"
 	"go.jetpack.io/devbox/internal/impl/shellcmd"
 	"go.jetpack.io/devbox/internal/planner/plansdk"
 )
 
+const DefaultName = "devbox.json"
+
 // Config defines a devbox environment as JSON.
 type Config struct {
 	// Packages is the slice of Nix packages that devbox makes available in
@@ -59,8 +58,9 @@ type Stage struct {
 	Command string `cue:"string" json:"command"`
 }
 
-func defaultConfig() *Config {
+func DefaultConfig() *Config {
 	return &Config{
+		Packages: []string{}, // initialize to empty slice instead of nil for consistent marshalling
 		Shell: &shellConfig{
 			Scripts: map[string]*shellcmd.Commands{
 				"test": {
@@ -80,6 +80,12 @@ func (c *Config) Hash() (string, error) {
 	return cuecfg.Hash(c)
 }
 
+func (c *Config) Equals(other *Config) bool {
+	hash1, _ := c.Hash()
+	hash2, _ := other.Hash()
+	return hash1 == hash2
+}
+
 func (c *Config) NixPkgsCommitHash() string {
 	if c == nil || c.Nixpkgs == nil || c.Nixpkgs.Commit == "" {
 		return plansdk.DefaultNixpkgsCommit
@@ -101,21 +107,27 @@ func (c *Config) InitHook() *shellcmd.Commands {
 	return c.Shell.InitHook
 }
 
+// SaveTo writes the config to a file.
+func (c *Config) SaveTo(path string) error {
+	cfgPath := filepath.Join(path, DefaultName)
+	return cuecfg.WriteFile(cfgPath, c)
+}
+
 func readConfig(path string) (*Config, error) {
 	cfg := &Config{}
 	return cfg, errors.WithStack(cuecfg.ParseFile(path, cfg))
 }
 
-// ReadConfig reads a devbox config file, and validates it.
-func ReadConfig(path string) (*Config, error) {
+// Load reads a devbox config file, and validates it.
+func Load(path string) (*Config, error) {
 	cfg, err := readConfig(path)
 	if err != nil {
 		return nil, err
 	}
 	return cfg, validateConfig(cfg)
 }
 
-func readConfigFromURL(url *url.URL) (*Config, error) {
+func LoadConfigFromURL(url *url.URL) (*Config, error) {
 	res, err := http.Get(url.String())
 	if err != nil {
 		return nil, errors.WithStack(err)
@@ -130,7 +142,10 @@ func readConfigFromURL(url *url.URL) (*Config, error) {
 	if !cuecfg.IsSupportedExtension(ext) {
 		ext = ".json"
 	}
-	return cfg, cuecfg.Unmarshal(data, ext, cfg)
+	if err = cuecfg.Unmarshal(data, ext, cfg); err != nil {
+		return nil, errors.WithStack(err)
+	}
+	return cfg, validateConfig(cfg)
 }
 
 // WriteConfig saves a devbox config file.
@@ -142,96 +157,9 @@ func WriteConfig(path string, cfg *Config) error {
 	return cuecfg.WriteFile(path, cfg)
 }
 
-// findProjectDir walks up the directory tree looking for a devbox.json
-// and upon finding it, will return the directory-path.
-//
-// If it doesn't find any devbox.json, then an error is returned.
-func findProjectDir(path string) (string, error) {
-	debug.Log("findProjectDir: path is %s\n", path)
-
-	// Sanitize the directory and use the absolute path as canonical form
-	absPath, err := filepath.Abs(path)
-	if err != nil {
-		return "", errors.WithStack(err)
-	}
-
-	// If the path  is specified, then we check directly for a config.
-	// Otherwise, we search the parent directories.
-	if path != "" {
-		return findProjectDirAtPath(absPath)
-	}
-	return findProjectDirFromParentDirSearch("/" /*root*/, absPath)
-}
-
-func findProjectDirAtPath(absPath string) (string, error) {
-	fi, err := os.Stat(absPath)
-	if err != nil {
-		return "", err
-	}
-
-	switch mode := fi.Mode(); {
-	case mode.IsDir():
-		if !fileutil.Exists(filepath.Join(absPath, configFilename)) {
-			return "", missingConfigError(absPath, false /*didCheckParents*/)
-		}
-		return absPath, nil
-	default: // assumes 'file' i.e. mode.IsRegular()
-		if !fileutil.Exists(filepath.Clean(absPath)) {
-			return "", missingConfigError(absPath, false /*didCheckParents*/)
-		}
-		// we return a directory from this function
-		return filepath.Dir(absPath), nil
-	}
-}
-
-func findProjectDirFromParentDirSearch(root string, absPath string) (string, error) {
-	cur := absPath
-	// Search parent directories for a devbox.json
-	for cur != root {
-		debug.Log("finding %s in dir: %s\n", configFilename, cur)
-		if fileutil.Exists(filepath.Join(cur, configFilename)) {
-			return cur, nil
-		}
-		cur = filepath.Dir(cur)
-	}
-	if fileutil.Exists(filepath.Join(cur, configFilename)) {
-		return cur, nil
-	}
-	return "", missingConfigError(absPath, true /*didCheckParents*/)
-}
-
-func missingConfigError(path string, didCheckParents bool) error {
-	var workingDir string
-	wd, err := os.Getwd()
-	if err == nil {
-		workingDir = wd
-	}
-	// We try to prettify the `path` before printing
-	if path == "." || path == "" || workingDir == path {
-		path = "this directory"
-	} else {
-		// Instead of a long absolute directory, print the relative directory
-
-		// if an error occurs, then just use `path`
-		if workingDir != "" {
-			relDir, err := filepath.Rel(workingDir, path)
-			if err == nil {
-				path = relDir
-			}
-		}
-	}
-
-	parentDirCheckAddendum := ""
-	if didCheckParents {
-		parentDirCheckAddendum = ", or any parent directories"
-	}
-
-	return usererr.New("No devbox.json found in %s%s. Did you run `devbox init` yet?", path, parentDirCheckAddendum)
-}
-
 func validateConfig(cfg *Config) error {
 	fns := []func(cfg *Config) error{
-		validateNixpkg,
+		ValidateNixpkg,
 		validateScripts,
 	}
 
@@ -252,16 +180,18 @@ func validateScripts(cfg *Config) error {
 			return errors.New("cannot have script with empty name in devbox.json")
 		}
 		if whitespace.MatchString(k) {
-			return errors.Errorf("cannot have script name with whitespace in devbox.json: %s", k)
+			return errors.Errorf(
+				"cannot have script name with whitespace in devbox.json: %s", k)
 		}
 		if strings.TrimSpace(scripts[k].String()) == "" {
-			return errors.Errorf("cannot have an empty script body in devbox.json: %s", k)
+			return errors.Errorf(
+				"cannot have an empty script body in devbox.json: %s", k)
 		}
 	}
 	return nil
 }
 
-func validateNixpkg(cfg *Config) error {
+func ValidateNixpkg(cfg *Config) error {
 	hash := cfg.NixPkgsCommitHash()
 	if hash == "" {
 		return nil

internal/devconfig/init.go

@@ -0,0 +1,37 @@
+// Copyright 2023 Jetpack Technologies Inc and contributors. All rights reserved.
+// Use of this source code is governed by the license in the LICENSE file.
+
+package devconfig
+
+import (
+	"fmt"
+	"io"
+	"path/filepath"
+	"strings"
+
+	"github.com/fatih/color"
+	"go.jetpack.io/devbox/internal/cuecfg"
+	"go.jetpack.io/devbox/internal/initrec"
+)
+
+func Init(dir string, writer io.Writer) (created bool, err error) {
+	cfgPath := filepath.Join(dir, DefaultName)
+
+	config := DefaultConfig()
+
+	// package suggestion
+	pkgsToSuggest, err := initrec.Get(dir)
+	if err != nil {
+		return false, err
+	}
+	if len(pkgsToSuggest) > 0 {
+		s := fmt.Sprintf("devbox add %s", strings.Join(pkgsToSuggest, " "))
+		fmt.Fprintf(
+			writer,
+			"We detected extra packages you may need. To install them, run `%s`\n",
+			color.HiYellowString(s),
+		)
+	}
+
+	return cuecfg.InitFile(cfgPath, config)
+}

internal/impl/devbox.go

@@ -18,7 +18,6 @@ import (
 	"text/tabwriter"
 	"text/template"
 
-	"github.com/fatih/color"
 	"github.com/pkg/errors"
 	"github.com/samber/lo"
 	"golang.org/x/exp/slices"
@@ -30,9 +29,9 @@ import (
 	"go.jetpack.io/devbox/internal/conf"
 	"go.jetpack.io/devbox/internal/cuecfg"
 	"go.jetpack.io/devbox/internal/debug"
+	"go.jetpack.io/devbox/internal/devconfig"
 	"go.jetpack.io/devbox/internal/envir"
 	"go.jetpack.io/devbox/internal/fileutil"
-	"go.jetpack.io/devbox/internal/initrec"
 	"go.jetpack.io/devbox/internal/lock"
 	"go.jetpack.io/devbox/internal/nix"
 	"go.jetpack.io/devbox/internal/planner/plansdk"
@@ -46,8 +45,6 @@ import (
 )
 
 const (
-	// configFilename is name of the JSON file that defines a devbox environment.
-	configFilename = "devbox.json"
 
 	// shellHistoryFile keeps the history of commands invoked inside devbox shell
 	shellHistoryFile = ".devbox/shell_history"
@@ -59,30 +56,8 @@ const (
 	arbitraryCmdFilename = ".cmd"
 )
 
-func InitConfig(dir string, writer io.Writer) (created bool, err error) {
-	cfgPath := filepath.Join(dir, configFilename)
-
-	config := defaultConfig()
-
-	// package suggestion
-	pkgsToSuggest, err := initrec.Get(dir)
-	if err != nil {
-		return false, err
-	}
-	if len(pkgsToSuggest) > 0 {
-		s := fmt.Sprintf("devbox add %s", strings.Join(pkgsToSuggest, " "))
-		fmt.Fprintf(
-			writer,
-			"We detected extra packages you may need. To install them, run `%s`\n",
-			color.HiYellowString(s),
-		)
-	}
-
-	return cuecfg.InitFile(cfgPath, config)
-}
-
 type Devbox struct {
-	cfg           *Config
+	cfg           *devconfig.Config
 	lockfile      *lock.File
 	nix           nix.Nixer
 	projectDir    string
@@ -100,9 +75,9 @@ func Open(path string, writer io.Writer) (*Devbox, error) {
 	if err != nil {
 		return nil, err
 	}
-	cfgPath := filepath.Join(projectDir, configFilename)
+	cfgPath := filepath.Join(projectDir, devconfig.DefaultName)
 
-	cfg, err := ReadConfig(cfgPath)
+	cfg, err := devconfig.Load(cfgPath)
 	if err != nil {
 		return nil, errors.WithStack(err)
 	}
@@ -130,7 +105,7 @@ func (d *Devbox) ProjectDir() string {
 	return d.projectDir
 }
 
-func (d *Devbox) Config() *Config {
+func (d *Devbox) Config() *devconfig.Config {
 	return d.cfg
 }
 
@@ -451,8 +426,7 @@ func (d *Devbox) GenerateEnvrcFile(force bool) error {
 
 // saveCfg writes the config file to the devbox directory.
 func (d *Devbox) saveCfg() error {
-	cfgPath := filepath.Join(d.projectDir, configFilename)
-	return cuecfg.WriteFile(cfgPath, d.cfg)
+	return d.cfg.SaveTo(d.ProjectDir())
 }
 
 func (d *Devbox) Services() (services.Services, error) {