feat: add cache dir to configuration + getter

internal/commands/configuration.go

@@ -3,8 +3,18 @@ package commands
 import (
 	"gopkg.in/yaml.v3"
 	"io/ioutil"
+	"os"
+	"os/user"
+	"path/filepath"
+	"strings"
 )
 
+const defaultCacheDirectory = "~/.cache/courgette"
+
+type CacheConfiguration struct {
+	Dir string `yaml:"dir"`
+}
+
 type RunnerConfiguration struct {
 	Labels map[string]string `yaml:"labels"`
 }
@@ -16,6 +26,25 @@ type ContainerConfiguration struct {
 type Configuration struct {
 	Containers ContainerConfiguration `yaml:"containers"`
 	Runner     RunnerConfiguration    `yaml:"runner"`
+	Cache      CacheConfiguration     `yaml:"cache"`
+}
+
+func (c Configuration) GetCacheDir() string {
+	currentUser, _ := user.Current()
+	homeDir := currentUser.HomeDir
+
+	cacheDir := c.Cache.Dir
+
+	if filepath.HasPrefix(cacheDir, "~") {
+		parts := strings.Split(cacheDir, "/")
+
+		finalParts := []string{homeDir}
+
+		finalParts = append(finalParts, parts[1:]...)
+		cacheDir = filepath.Join(finalParts...)
+	}
+
+	return cacheDir
 }
 
 func applyConfigDefaults(config Configuration) Configuration {
@@ -23,15 +52,38 @@ func applyConfigDefaults(config Configuration) Configuration {
 		Containers: ContainerConfiguration{
 			Driver: "podman",
 		},
+		Cache: CacheConfiguration{
+			Dir: defaultCacheDirectory,
+		},
 	}
 
 	if config.Containers.Driver == "" {
 		config.Containers.Driver = defaults.Containers.Driver
 	}
 
+	if config.Cache.Dir == "" {
+		config.Cache.Dir = defaults.Cache.Dir
+	}
+
 	return config
 }
 
+func NewConfigFromYamlBytes(configRaw []byte) (*Configuration, error) {
+	var config Configuration
+
+	if yamlError := yaml.Unmarshal(configRaw, &config); yamlError != nil {
+		return nil, yamlError
+	}
+
+	config = applyConfigDefaults(config)
+
+	if err := os.MkdirAll(config.Cache.Dir, 0755); err != nil {
+		return nil, err
+	}
+
+	return &config, nil
+}
+
 func NewConfigFromFile(configPath string) (*Configuration, error) {
 	configRaw, err := ioutil.ReadFile(configPath)
 
@@ -39,13 +91,5 @@ func NewConfigFromFile(configPath string) (*Configuration, error) {
 		return nil, err
 	}
 
-	var config Configuration
-
-	if yamlError := yaml.Unmarshal(configRaw, &config); yamlError != nil {
-		return nil, yamlError
-	}
-
-	config = applyConfigDefaults(config)
-
-	return &config, nil
+	return NewConfigFromYamlBytes(configRaw)
 }

internal/commands/configuration_test.go

@@ -0,0 +1,47 @@
+package commands
+
+import (
+	"os/user"
+	"path/filepath"
+	"strings"
+	"testing"
+)
+
+func TestGetCacheDirDefault(t *testing.T) {
+	configuration, _ := NewConfigFromYamlBytes([]byte(""))
+
+	parts := strings.Split(defaultCacheDirectory, "/")
+	user, _ := user.Current()
+	defaultPathParts := []string{user.HomeDir}
+	defaultPathParts = append(defaultPathParts, parts[1:]...)
+	defaultPath := filepath.Join(defaultPathParts...)
+	if configuration.GetCacheDir() != defaultPath {
+		t.Errorf("Expected default %s, got %s instead.", defaultPath, configuration.GetCacheDir())
+	}
+}
+
+func TestGetCacheDirExpandsTilde(t *testing.T) {
+	configuration, _ := NewConfigFromYamlBytes([]byte(""))
+	user, _ := user.Current()
+
+	cacheDir := configuration.GetCacheDir()
+	if filepath.HasPrefix(configuration.GetCacheDir(), "~") {
+		t.Errorf("Expected tilde to be expanded, was not.")
+	}
+
+	if !filepath.HasPrefix(cacheDir, user.HomeDir) {
+		t.Errorf("Expected tilder to be expanded, was not.")
+	}
+}
+
+func TestGetCacheDirReturnsCachePath(t *testing.T) {
+	sample := `
+    cache:
+        dir: "/tmp/cache-dir"
+    `
+	configuration, _ := NewConfigFromYamlBytes([]byte(sample))
+	cacheDir := configuration.GetCacheDir()
+	if cacheDir != "/tmp/cache-dir" {
+		t.Errorf("Unexpected cache path: %s", cacheDir)
+	}
+}