Reload server and edit configuration. (#15)

The first iteration for config editor and server reload from the web interface.

config/handler.go

@@ -0,0 +1,101 @@
+package config
+
+import (
+	"fmt"
+	"io/ioutil"
+	"os"
+	"path"
+
+	"github.com/ajnavarro/distribyted"
+	"github.com/sirupsen/logrus"
+	"gopkg.in/yaml.v3"
+)
+
+type EventFunc func(event string)
+type ReloadFunc func(*Root, EventFunc) error
+
+type Handler struct {
+	p          string
+	reloadFunc ReloadFunc
+}
+
+func NewHandler(path string) *Handler {
+	return &Handler{p: path}
+}
+
+func (c *Handler) createFromTemplateFile() ([]byte, error) {
+	t, err := distribyted.HttpFS.Open("/templates/config_template.yaml")
+	if err != nil {
+		return nil, err
+	}
+	defer t.Close()
+
+	tb, err := ioutil.ReadAll(t)
+	if err != nil {
+		return nil, err
+	}
+
+	if err := os.MkdirAll(path.Dir(c.p), 0744); err != nil {
+		return nil, fmt.Errorf("error creating path for configuration file: %s, %w", c.p, err)
+	}
+	return tb, ioutil.WriteFile(c.p, tb, 0644)
+}
+
+func (c *Handler) GetRaw() ([]byte, error) {
+	f, err := ioutil.ReadFile(c.p)
+	if os.IsNotExist(err) {
+		logrus.WithField("file", c.p).Info("configuration file does not exist, creating from template file")
+		return c.createFromTemplateFile()
+	}
+
+	if err != nil {
+		return nil, fmt.Errorf("error reading configuration file: %w", err)
+	}
+
+	return f, nil
+}
+
+func (c *Handler) Get() (*Root, error) {
+	b, err := c.GetRaw()
+	if err != nil {
+		return nil, err
+	}
+
+	conf := &Root{}
+	if err := yaml.Unmarshal(b, conf); err != nil {
+		return nil, fmt.Errorf("error parsing configuration file: %w", err)
+	}
+
+	conf = AddDefaults(conf)
+
+	return conf, nil
+}
+
+func (c *Handler) OnReload(reloadFunc ReloadFunc) {
+	c.reloadFunc = reloadFunc
+}
+
+func (c *Handler) Reload(ef EventFunc) error {
+	if ef == nil {
+		ef = func(string) {}
+	}
+
+	conf, err := c.Get()
+	if err != nil {
+		return err
+	}
+
+	if c.reloadFunc != nil {
+		return c.reloadFunc(conf, ef)
+	}
+
+	return nil
+}
+
+func (c *Handler) Set(b []byte) error {
+	if err := yaml.Unmarshal(b, &Root{}); err != nil {
+		return fmt.Errorf("error parsing configuration file: %w", err)
+	}
+
+	return ioutil.WriteFile(c.p, b, 0644)
+}

config/model.go

@@ -11,8 +11,8 @@ type Root struct {
 type MountPoint struct {
 	Path     string `yaml:"path"`
 	Torrents []struct {
-		MagnetURI   string `yaml:"magnetUri"`
-		TorrentPath string `yaml:"torrentPath"`
+		MagnetURI   string `yaml:"magnetUri,omitempty"`
+		TorrentPath string `yaml:"torrentPath,omitempty"`
 		FolderName  string `yaml:"folderName,omitempty"`
 	} `yaml:"torrents"`
 }
@@ -22,7 +22,7 @@ func AddDefaults(r *Root) *Root {
 		r.MaxCacheSize = 1024 // 1GB
 	}
 	if r.MetadataFolder == "" {
-		r.MetadataFolder = "./metadata"
+		r.MetadataFolder = "./distribyted-data/metadata"
 	}
 
 	return r