runtime: refactor NewRuntime and NewRuntimeFromConfig

we had two functions NewRuntimeFromConfig and NewRuntime that differed
only for the config file they use.

Move comon logic to newRuntimeFromConfig and let it lookup the
configuration file to use when one is not specified.

Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>

1 files changed, 32 insertions, 76 deletions

diff --git a/libpod/runtime.go b/libpod/runtime.go
index fa208a2ca..b8e933aaa 100644
--- a/libpod/runtime.go
+++ b/libpod/runtime.go
@@ -324,6 +324,22 @@ func SetXdgRuntimeDir(val string) error {
 // NewRuntime creates a new container runtime
 // Options can be passed to override the default configuration for the runtime
 func NewRuntime(options ...RuntimeOption) (runtime *Runtime, err error) {
+	return newRuntimeFromConfig("", options...)
+}
+
+// NewRuntimeFromConfig creates a new container runtime using the given
+// configuration file for its default configuration. Passed RuntimeOption
+// functions can be used to mutate this configuration further.
+// An error will be returned if the configuration file at the given path does
+// not exist or cannot be loaded
+func NewRuntimeFromConfig(userConfigPath string, options ...RuntimeOption) (runtime *Runtime, err error) {
+	if userConfigPath == "" {
+		return nil, errors.New("invalid configuration file specified")
+	}
+	return newRuntimeFromConfig(userConfigPath, options...)
+}
+
+func newRuntimeFromConfig(userConfigPath string, options ...RuntimeOption) (runtime *Runtime, err error) {
 	runtime = new(Runtime)
 	runtime.config = new(RuntimeConfig)
 	runtime.configuredFrom = new(runtimeConfiguredFrom)
@@ -358,11 +374,6 @@ func NewRuntime(options ...RuntimeOption) (runtime *Runtime, err error) {
 
 		rootlessConfigPath = filepath.Join(home, ".config/containers/libpod.conf")
 
-		configPath = rootlessConfigPath
-		if _, err := os.Stat(configPath); err != nil {
-			foundConfig = false
-		}
-
 		runtimeDir, err := util.GetRootlessRuntimeDir()
 		if err != nil {
 			return nil, err
@@ -374,6 +385,20 @@ func NewRuntime(options ...RuntimeOption) (runtime *Runtime, err error) {
 			return nil, errors.Wrapf(err, "cannot set XDG_RUNTIME_DIR")
 		}
 
+	}
+
+	if userConfigPath != "" {
+		configPath = userConfigPath
+		if _, err := os.Stat(configPath); err != nil {
+			// If the user specified a config file, we must fail immediately
+			// when it doesn't exist
+			return nil, errors.Wrapf(err, "cannot stat %s", configPath)
+		}
+	} else if rootless.IsRootless() {
+		configPath = rootlessConfigPath
+		if _, err := os.Stat(configPath); err != nil {
+			foundConfig = false
+		}
 	} else if _, err := os.Stat(OverrideConfigPath); err == nil {
 		// Use the override configuration path
 		configPath = OverrideConfigPath
@@ -465,80 +490,9 @@ func NewRuntime(options ...RuntimeOption) (runtime *Runtime, err error) {
 	return runtime, nil
 }
 
-// NewRuntimeFromConfig creates a new container runtime using the given
-// configuration file for its default configuration. Passed RuntimeOption
-// functions can be used to mutate this configuration further.
-// An error will be returned if the configuration file at the given path does
-// not exist or cannot be loaded
-func NewRuntimeFromConfig(configPath string, options ...RuntimeOption) (runtime *Runtime, err error) {
-	runtime = new(Runtime)
-	runtime.config = new(RuntimeConfig)
-	runtime.configuredFrom = new(runtimeConfiguredFrom)
-
-	// Set three fields not in the TOML config
-	runtime.config.StateType = defaultRuntimeConfig.StateType
-	runtime.config.OCIRuntime = defaultRuntimeConfig.OCIRuntime
-
-	storageConf, err := util.GetDefaultStoreOptions()
-	if err != nil {
-		return nil, errors.Wrapf(err, "error retrieving storage config")
-	}
-	runtime.config.StorageConfig = storageConf
-	runtime.config.StaticDir = filepath.Join(storageConf.GraphRoot, "libpod")
-	runtime.config.VolumePath = filepath.Join(storageConf.GraphRoot, "volumes")
-
-	tmpDir, err := getDefaultTmpDir()
-	if err != nil {
-		return nil, err
-	}
-	runtime.config.TmpDir = tmpDir
-	if rootless.IsRootless() {
-		runtimeDir, err := util.GetRootlessRuntimeDir()
-		if err != nil {
-			return nil, err
-		}
-		// containers/image uses XDG_RUNTIME_DIR to locate the auth file.
-		// So make sure the env variable is set.
-		if err := SetXdgRuntimeDir(runtimeDir); err != nil {
-			return nil, errors.Wrapf(err, "cannot set XDG_RUNTIME_DIR")
-		}
-	}
-
-	// Check to see if the given configuration file exists
-	if _, err := os.Stat(configPath); err != nil {
-		return nil, errors.Wrapf(err, "error checking existence of configuration file %s", configPath)
-	}
-
-	// Read contents of the config file
-	contents, err := ioutil.ReadFile(configPath)
-	if err != nil {
-		return nil, errors.Wrapf(err, "error reading configuration file %s", configPath)
-	}
-
-	// Decode configuration file
-	if _, err := toml.Decode(string(contents), runtime.config); err != nil {
-		return nil, errors.Wrapf(err, "error decoding configuration from file %s", configPath)
-	}
-
-	// Overwrite the config with user-given configuration options
-	for _, opt := range options {
-		if err := opt(runtime); err != nil {
-			return nil, errors.Wrapf(err, "error configuring runtime")
-		}
-	}
-
-	if err := makeRuntime(runtime); err != nil {
-		return nil, err
-	}
-
-	return runtime, nil
-}
-
 // Make a new runtime based on the given configuration
 // Sets up containers/storage, state store, OCI runtime
 func makeRuntime(runtime *Runtime) (err error) {
-	runtime.config.EventsLogFilePath = filepath.Join(runtime.config.TmpDir, "events", "events.log")
-
 	// Backward compatibility for `runtime_path`
 	if runtime.config.RuntimePath != nil {
 		// Don't print twice in rootless mode.
@@ -697,6 +651,8 @@ func makeRuntime(runtime *Runtime) (err error) {
 		runtime.config.VolumePath = dbConfig.VolumePath
 	}
 
+	runtime.config.EventsLogFilePath = filepath.Join(runtime.config.TmpDir, "events", "events.log")
+
 	logrus.Debugf("Using graph driver %s", runtime.config.StorageConfig.GraphDriverName)
 	logrus.Debugf("Using graph root %s", runtime.config.StorageConfig.GraphRoot)
 	logrus.Debugf("Using run root %s", runtime.config.StorageConfig.RunRoot)