Enable accessing config from gitconfig file or env variables

pkg/config.go

@@ -0,0 +1,113 @@
+package pkg
+
+import (
+	"os"
+	"path"
+	"strings"
+
+	"github.com/go-git/go-git/v5/config"
+	plumbing "github.com/go-git/go-git/v5/plumbing/format/config"
+	"github.com/mitchellh/go-homedir"
+)
+
+const (
+	CfgSection     = "gitget"
+	CfgReposRoot   = "reposRoot"
+	CfgDefaultHost = "defaultHost"
+
+	EnvReposRoot   = "GITGET_REPOSROOT"
+	EnvDefaultHost = "GITGET_DEFAULTHOST"
+
+	DefaultReposRootSubpath = "repositories"
+	DefaultHost             = "github.com"
+)
+
+var Cfg *Conf
+
+// Conf provides methods for accessing configuration values
+// Values are looked up in the following order: env variable, gitignore file, default value
+type Conf struct {
+	gitconfig *config.Config
+}
+
+func LoadConf() {
+	// We don't care if loading gitconfig file throws an error
+	// When gitconfig is nil, getters will just return the default values
+	gitconfig, _ := config.LoadConfig(config.GlobalScope)
+
+	Cfg = &Conf{
+		gitconfig: gitconfig,
+	}
+}
+
+func (c *Conf) ReposRoot() string {
+	defReposRoot := path.Join(home(), DefaultReposRootSubpath)
+
+	reposRoot := os.Getenv(EnvReposRoot)
+	if reposRoot != "" {
+		return reposRoot
+	}
+
+	if c.gitconfig == nil {
+		return defReposRoot
+	}
+
+	gitget := c.findConfigSection(CfgSection)
+	if gitget == nil {
+		return defReposRoot
+	}
+
+	reposRoot = gitget.Option(CfgReposRoot)
+	reposRoot = strings.TrimSpace(reposRoot)
+	if reposRoot == "" {
+		return defReposRoot
+	}
+
+	return reposRoot
+}
+
+func (c *Conf) DefaultHost() string {
+	defaultHost := os.Getenv(EnvDefaultHost)
+	if defaultHost != "" {
+		return defaultHost
+	}
+
+	if c.gitconfig == nil {
+		return DefaultHost
+	}
+
+	gitget := c.findConfigSection(CfgSection)
+	if gitget == nil {
+		return DefaultHost
+	}
+
+	defaultHost = gitget.Option(CfgDefaultHost)
+	defaultHost = strings.TrimSpace(defaultHost)
+	if defaultHost == "" {
+		return DefaultHost
+	}
+
+	return defaultHost
+}
+
+func (c *Conf) findConfigSection(name string) *plumbing.Section {
+	for _, s := range c.gitconfig.Raw.Sections {
+		if s.Name == name {
+			return s
+		}
+	}
+
+	return nil
+}
+
+// home returns path to a home directory or empty string if can't be found
+// Using empty string means that in the unlikely situation where home dir can't be found
+// and there's no reposRoot specified in the global config, the current dir will be used as repos root.
+func home() string {
+	home, err := homedir.Dir()
+	if err != nil {
+		return ""
+	}
+
+	return home
+}