feature: Add remote config support

docs/configuration.md

@@ -7,6 +7,10 @@
   - [`skip_output`](#skip_output)
   - [`source_dir`](#source_dir)
   - [`source_dir_local`](#source_dir_local)
+- [`remote` (Beta :test_tube:)](#remote)
+  - [`git_url`](#git_url)
+  - [`ref`](#ref)
+  - [`config`](#config)
 - [Hook](#git-hook)
   - [`files`](#files-global)
   - [`parallel`](#parallel)
@@ -57,23 +61,20 @@ colors: false
 
 ### `extends`
 
-You can extend your config with another one YAML file.
+You can extend your config with another one YAML file. Its content will be merged. Extends for `lefthook.yml`, `lefthook-local.yml`, and [`remote`](#remote) configs are handled separately, so you can have different extends in these files.
 
 **Example**
 
 ```yml
 # lefthook.yml
 
 extends:
-  - $HOME/work/lefthook-extend.yml
-  - $HOME/work/lefthook-extend-2.yml
+  - /home/user/work/lefthook-extend.yml
+  - /home/user/work/lefthook-extend-2.yml
+  - lefthook-extends/file.yml
+  - ../extend.yml
 ```
 
-**Notes**
-
-Files for extend should *not* be named "lefthook.yml". All file names should be unique.
-
-
 ### `min_version`
 
 If you want to specify a minimum version for lefthook binary (e.g. if you need some features older versions don't have) you can set this option.
@@ -138,6 +139,80 @@ Change a directory for *local* script files (not stored in VCS).
 
 This option is useful if you have a `lefthook-local.yml` config file and want to reference different scripts there.
 
+## `remote`
+
+> :test_tube: This feature is in **Beta** version
+
+You can provide a remote config if you want to share your lefthook configuration across many projects. Lefthook will automatically download and merge the configuration into your local `lefthook.yml`.
+
+You can use [`extends`](#extends) related to the config file (not absolute paths).
+
+If you provide [`scripts`](#scripts) in a remote file, the [scripts](#source_dir) folder must be in the **root of the repository**.
+
+**Note**
+
+Configuration in `remote` will be merged to confiuration in `lefthook.yml`, so the priority will be the following:
+
+- `lefthook.yml`
+- `remote`
+- `lefthook-local.yml`
+
+This can be changed in the future. For convenience, please use `remote` configuration without any hooks configuration in `lefthook.yml`.
+
+### `git_url`
+
+A URL to Git repository. It will be accessed with priveleges of the machine lefthook runs on.
+
+**Example**
+
+```yml
+# lefthook.yml
+
+remote:
+  git_url: git@github.com:evilmartians/lefthook
+```
+
+Or
+
+```yml
+# lefthook.yml
+
+remote:
+  git_url: https://github.com/evilmartians/lefthook
+```
+
+### `ref`
+
+An optional *branch* or *tag* name.
+
+**Example**
+
+```yml
+# lefthook.yml
+
+remote:
+  git_url: git@github.com:evilmartians/lefthook
+  ref: v1.0.0
+```
+
+
+### `config`
+
+**Default:** `lefthook.yml`
+
+An optional config path from remote's root.
+
+**Example**
+
+```yml
+# lefthook.yml
+
+remote:
+  git_url: git@github.com:evilmartians/remote
+  ref: v1.0.0
+  config: examples/ruby-linter.yml
+```
+
 ## Git hook
 
 Commands and scripts are defined for git hooks. You can defined a hook for all hooks listed in [this file](../internal/config/available_hooks.go).

examples/remote/ping.yml

@@ -0,0 +1,13 @@
+# Test `remote` config of lefthook.
+#
+# # lefthook.yml
+#
+# remote:
+#   git_url: git@github.com:evilmartians/lefthook
+#   config: examples/remote/ping.yml
+#
+# $ lefthook run pre-commit
+
+pre-commit:
+  commands:
+    run: echo pong

go.mod

@@ -24,7 +24,7 @@ require (
 	github.com/inconshreveable/mousetrap v1.0.0 // indirect
 	github.com/magiconair/properties v1.8.6 // indirect
 	github.com/mattn/go-colorable v0.1.12 // indirect
-	github.com/mattn/go-isatty v0.0.14 // indirect
+	github.com/mattn/go-isatty v0.0.14
 	github.com/pelletier/go-toml v1.9.5 // indirect
 	github.com/pelletier/go-toml/v2 v2.0.1 // indirect
 	github.com/spf13/cast v1.5.0 // indirect

internal/config/config.go

@@ -7,6 +7,7 @@ import (
 type Config struct {
 	Colors         bool     `mapstructure:"colors"`
 	Extends        []string `mapstructure:"extends"`
+	Remote         Remote   `mapstructure:"remote"`
 	MinVersion     string   `mapstructure:"min_version"`
 	SkipOutput     []string `mapstructure:"skip_output"`
 	SourceDir      string   `mapstructure:"source_dir"`

internal/config/load.go

@@ -1,15 +1,20 @@
 package config
 
 import (
+	"fmt"
 	"path/filepath"
 	"regexp"
 	"strings"
 
 	"github.com/spf13/afero"
 	"github.com/spf13/viper"
+
+	"github.com/evilmartians/lefthook/internal/git"
+	"github.com/evilmartians/lefthook/internal/log"
 )
 
 const (
+	DefaultConfigName     = "lefthook.yml"
 	DefaultSourceDir      = ".lefthook"
 	DefaultSourceDirLocal = ".lefthook-local"
 	DefaultColorsEnabled  = true
@@ -18,13 +23,13 @@ const (
 var hookKeyRegexp = regexp.MustCompile(`^(?P<hookName>[^.]+)\.(scripts|commands)`)
 
 // Loads configs from the given directory with extensions.
-func Load(fs afero.Fs, path string) (*Config, error) {
-	global, err := read(fs, path, "lefthook")
+func Load(fs afero.Fs, repo *git.Repository) (*Config, error) {
+	global, err := read(fs, repo.RootPath, "lefthook")
 	if err != nil {
 		return nil, err
 	}
 
-	extends, err := mergeAllExtends(fs, path)
+	extends, err := mergeAll(fs, repo)
 	if err != nil {
 		return nil, err
 	}
@@ -61,43 +66,93 @@ func read(fs afero.Fs, path string, name string) (*viper.Viper, error) {
 	return v, nil
 }
 
-// Merges extends from .lefthook and .lefthook-local.
-func mergeAllExtends(fs afero.Fs, path string) (*viper.Viper, error) {
-	extends, err := read(fs, path, "lefthook")
+// mergeAll merges remotes and extends from .lefthook and .lefthook-local.
+func mergeAll(fs afero.Fs, repo *git.Repository) (*viper.Viper, error) {
+	extends, err := read(fs, repo.RootPath, "lefthook")
 	if err != nil {
 		return nil, err
 	}
 
-	if err := extend(fs, extends); err != nil {
+	if err := extend(extends, repo.RootPath); err != nil {
 		return nil, err
 	}
 
-	extends.SetConfigName("lefthook-local")
-	if err := extends.MergeInConfig(); err != nil {
+	if err := mergeRemote(fs, repo, extends); err != nil {
+		return nil, err
+	}
+
+	if err := merge("lefthook-local", "", extends); err != nil {
 		if _, notFoundErr := err.(viper.ConfigFileNotFoundError); !notFoundErr {
 			return nil, err
 		}
 	}
 
-	if err := extend(fs, extends); err != nil {
+	if err := extend(extends, repo.RootPath); err != nil {
 		return nil, err
 	}
 
 	return extends, nil
 }
 
-func extend(fs afero.Fs, v *viper.Viper) error {
-	for _, path := range v.GetStringSlice("extends") {
-		name := strings.TrimSuffix(filepath.Base(path), filepath.Ext(path))
+// mergeRemote merges remote config to the current one.
+func mergeRemote(fs afero.Fs, repo *git.Repository, v *viper.Viper) error {
+	var remote Remote
+	err := v.UnmarshalKey("remote", &remote)
+	if err != nil {
+		return err
+	}
 
-		another, err := read(fs, filepath.Dir(path), name)
-		if err != nil {
-			return err
+	if !remote.Configured() {
+		return nil
+	}
+
+	remotePath := repo.RemoteFolder(remote.GitURL)
+	configFile := DefaultConfigName
+	if len(remote.Config) > 0 {
+		configFile = remote.Config
+	}
+	configPath := filepath.Join(remotePath, configFile)
+
+	log.Debugf("Merging remote config: %s", configPath)
+
+	_, err = fs.Stat(configPath)
+	if err != nil {
+		return nil
+	}
+
+	if err := merge("remote", configPath, v); err != nil {
+		return err
+	}
+
+	if err := extend(v, filepath.Dir(configPath)); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+// extend merges all files listed in 'extends' option into the config.
+func extend(v *viper.Viper, root string) error {
+	for i, path := range v.GetStringSlice("extends") {
+		if !filepath.IsAbs(path) {
+			path = filepath.Join(root, path)
 		}
-		if err = v.MergeConfigMap(another.AllSettings()); err != nil {
+		if err := merge(fmt.Sprintf("extend_%d", i), path, v); err != nil {
 			return err
 		}
 	}
+	return nil
+}
+
+// merge merges the configuration using viper builtin MergeInConfig.
+func merge(name, path string, v *viper.Viper) error {
+	v.SetConfigName(name)
+	if len(path) > 0 {
+		v.SetConfigFile(path)
+	}
+	if err := v.MergeInConfig(); err != nil {
+		return err
+	}
 
 	return nil
 }
@@ -112,7 +167,7 @@ func unmarshalConfigs(base, extra *viper.Viper, c *Config) error {
 	}
 
 	// For extra non-git hooks.
-	// This behavior will be deprecated in next versions.
+	// This behavior may be deprecated in next versions.
 	for _, maybeHook := range base.AllKeys() {
 		if !hookKeyRegexp.MatchString(maybeHook) {
 			continue