feat(plugins): major improvement in plugins golang code

pkg/plugins/app_plugin.go

@@ -0,0 +1,38 @@
+package plugins
+
+import (
+	"encoding/json"
+
+	"github.com/grafana/grafana/pkg/models"
+)
+
+type AppPluginPage struct {
+	Text    string          `json:"text"`
+	Icon    string          `json:"icon"`
+	Url     string          `json:"url"`
+	ReqRole models.RoleType `json:"reqRole"`
+}
+
+type AppPluginCss struct {
+	Light string `json:"light"`
+	Dark  string `json:"dark"`
+}
+
+type AppPlugin struct {
+	FrontendPluginBase
+	Enabled bool           `json:"enabled"`
+	Pinned  bool           `json:"pinned"`
+	Css     *AppPluginCss  `json:"css"`
+	Page    *AppPluginPage `json:"page"`
+}
+
+func (p *AppPlugin) Load(decoder *json.Decoder, pluginDir string) error {
+	if err := decoder.Decode(&p); err != nil {
+		return err
+	}
+
+	p.PluginDir = pluginDir
+	p.initFrontendPlugin()
+	Apps[p.Id] = p
+	return nil
+}

pkg/plugins/datasource_plugin.go

@@ -0,0 +1,25 @@
+package plugins
+
+import "encoding/json"
+
+type DataSourcePlugin struct {
+	FrontendPluginBase
+	DefaultMatchFormat string `json:"defaultMatchFormat"`
+	Annotations        bool   `json:"annotations"`
+	Metrics            bool   `json:"metrics"`
+	BuiltIn            bool   `json:"builtIn"`
+	Mixed              bool   `json:"mixed"`
+	App                string `json:"app"`
+}
+
+func (p *DataSourcePlugin) Load(decoder *json.Decoder, pluginDir string) error {
+	if err := decoder.Decode(&p); err != nil {
+		return err
+	}
+
+	p.PluginDir = pluginDir
+	p.initFrontendPlugin()
+	DataSources[p.Id] = p
+
+	return nil
+}

pkg/plugins/frontend_plugin.go

@@ -0,0 +1,47 @@
+package plugins
+
+import (
+	"net/url"
+	"path"
+)
+
+type FrontendPluginBase struct {
+	PluginBase
+	Module     string `json:"module"`
+	StaticRoot string `json:"staticRoot"`
+}
+
+func (fp *FrontendPluginBase) initFrontendPlugin() {
+	if fp.StaticRoot != "" {
+		StaticRoutes = append(StaticRoutes, &PluginStaticRoute{
+			Directory: fp.StaticRoot,
+			PluginId:  fp.Id,
+		})
+	}
+
+	fp.Info.Logos.Small = evalRelativePluginUrlPath(fp.Info.Logos.Small, fp.Id)
+	fp.Info.Logos.Large = evalRelativePluginUrlPath(fp.Info.Logos.Large, fp.Id)
+
+	fp.handleModuleDefaults()
+}
+
+func (fp *FrontendPluginBase) handleModuleDefaults() {
+	if fp.Module != "" {
+		return
+	}
+
+	if fp.StaticRoot != "" {
+		fp.Module = path.Join("plugins", fp.Type, fp.Id, "module")
+		return
+	}
+
+	fp.Module = path.Join("app/plugins", fp.Type, fp.Id, "module")
+}
+
+func evalRelativePluginUrlPath(pathStr string, pluginId string) string {
+	u, _ := url.Parse(pathStr)
+	if u.IsAbs() {
+		return pathStr
+	}
+	return path.Join("public/plugins", pluginId, pathStr)
+}

pkg/plugins/models.go

@@ -1,15 +1,22 @@
 package plugins
 
 import (
+	"encoding/json"
+
 	"github.com/grafana/grafana/pkg/models"
 )
 
-type PluginCommon struct {
-	Type       string     `json:"type"`
-	Name       string     `json:"name"`
-	Id         string     `json:"id"`
-	StaticRoot string     `json:"staticRoot"`
-	Info       PluginInfo `json:"info"`
+type PluginLoader interface {
+	Load(decoder *json.Decoder, pluginDir string) error
+}
+
+type PluginBase struct {
+	Type      string     `json:"type"`
+	Name      string     `json:"name"`
+	Id        string     `json:"id"`
+	App       string     `json:"app"`
+	Info      PluginInfo `json:"info"`
+	PluginDir string     `json:"-"`
 }
 
 type PluginInfo struct {
@@ -29,30 +36,11 @@ type PluginLogos struct {
 	Large string `json:"large"`
 }
 
-type DataSourcePlugin struct {
-	PluginCommon
-	Module             string                 `json:"module"`
-	ServiceName        string                 `json:"serviceName"`
-	Partials           map[string]interface{} `json:"partials"`
-	DefaultMatchFormat string                 `json:"defaultMatchFormat"`
-	Annotations        bool                   `json:"annotations"`
-	Metrics            bool                   `json:"metrics"`
-	BuiltIn            bool                   `json:"builtIn"`
-	Mixed              bool                   `json:"mixed"`
-	App                string                 `json:"app"`
-}
-
 type PluginStaticRoute struct {
 	Directory string
 	PluginId  string
 }
 
-type PanelPlugin struct {
-	PluginCommon
-	Module string `json:"module"`
-	App    string `json:"app"`
-}
-
 type ApiPluginRoute struct {
 	Path            string          `json:"path"`
 	Method          string          `json:"method"`
@@ -60,34 +48,11 @@ type ApiPluginRoute struct {
 	ReqGrafanaAdmin bool            `json:"reqGrafanaAdmin"`
 	ReqRole         models.RoleType `json:"reqRole"`
 	Url             string          `json:"url"`
-	App             string          `json:"app"`
-}
-
-type AppPluginPage struct {
-	Text    string          `json:"text"`
-	Icon    string          `json:"icon"`
-	Url     string          `json:"url"`
-	ReqRole models.RoleType `json:"reqRole"`
-}
-
-type AppPluginCss struct {
-	Light string `json:"light"`
-	Dark  string `json:"dark"`
 }
 
 type ApiPlugin struct {
-	PluginCommon
+	PluginBase
 	Routes []*ApiPluginRoute `json:"routes"`
-	App    string            `json:"app"`
-}
-
-type AppPlugin struct {
-	PluginCommon
-	Enabled bool           `json:"enabled"`
-	Pinned  bool           `json:"pinned"`
-	Module  string         `json:"module"`
-	Css     *AppPluginCss  `json:"css"`
-	Page    *AppPluginPage `json:"page"`
 }
 
 type EnabledPlugins struct {

pkg/plugins/panel_plugin.go

@@ -0,0 +1,19 @@
+package plugins
+
+import "encoding/json"
+
+type PanelPlugin struct {
+	FrontendPluginBase
+}
+
+func (p *PanelPlugin) Load(decoder *json.Decoder, pluginDir string) error {
+	if err := decoder.Decode(&p); err != nil {
+		return err
+	}
+
+	p.PluginDir = pluginDir
+	p.initFrontendPlugin()
+	Panels[p.Id] = p
+
+	return nil
+}

pkg/plugins/plugins.go

@@ -5,10 +5,10 @@ import (
 	"encoding/json"
 	"errors"
 	"io"
-	"net/url"
 	"os"
 	"path"
 	"path/filepath"
+	"reflect"
 	"strings"
 	"text/template"
 
@@ -24,6 +24,7 @@ var (
 	ApiPlugins   map[string]*ApiPlugin
 	StaticRoutes []*PluginStaticRoute
 	Apps         map[string]*AppPlugin
+	PluginTypes  map[string]interface{}
 )
 
 type PluginScanner struct {
@@ -37,6 +38,12 @@ func Init() error {
 	StaticRoutes = make([]*PluginStaticRoute, 0)
 	Panels = make(map[string]*PanelPlugin)
 	Apps = make(map[string]*AppPlugin)
+	PluginTypes = map[string]interface{}{
+		"panel":      PanelPlugin{},
+		"datasource": DataSourcePlugin{},
+		"api":        ApiPlugin{},
+		"app":        AppPlugin{},
+	}
 
 	scan(path.Join(setting.StaticRootPath, "app/plugins"))
 	checkPluginPaths()
@@ -115,27 +122,7 @@ func (scanner *PluginScanner) walker(currentPath string, f os.FileInfo, err erro
 	return nil
 }
 
-func evalRelativePluginUrlPath(pathStr string, pluginId string) string {
-	u, _ := url.Parse(pathStr)
-	if u.IsAbs() {
-		return pathStr
-	}
-	return path.Join("public/plugins", pluginId, pathStr)
-}
-
-func addPublicContent(plugin *PluginCommon, currentDir string) {
-	if plugin.StaticRoot != "" {
-		StaticRoutes = append(StaticRoutes, &PluginStaticRoute{
-			Directory: path.Join(currentDir, plugin.StaticRoot),
-			PluginId:  plugin.Id,
-		})
-	}
-
-	plugin.Info.Logos.Small = evalRelativePluginUrlPath(plugin.Info.Logos.Small, plugin.Id)
-	plugin.Info.Logos.Large = evalRelativePluginUrlPath(plugin.Info.Logos.Large, plugin.Id)
-}
-
-func interpolatePluginJson(reader io.Reader, pluginCommon *PluginCommon) (io.Reader, error) {
+func interpolatePluginJson(reader io.Reader, pluginCommon *PluginBase) (io.Reader, error) {
 	buf := new(bytes.Buffer)
 	buf.ReadFrom(reader)
 	jsonStr := buf.String() //
@@ -167,7 +154,7 @@ func (scanner *PluginScanner) loadPluginJson(pluginJsonFilePath string) error {
 	defer reader.Close()
 
 	jsonParser := json.NewDecoder(reader)
-	pluginCommon := PluginCommon{}
+	pluginCommon := PluginBase{}
 	if err := jsonParser.Decode(&pluginCommon); err != nil {
 		return err
 	}
@@ -177,52 +164,21 @@ func (scanner *PluginScanner) loadPluginJson(pluginJsonFilePath string) error {
 	}
 
 	reader.Seek(0, 0)
-
 	if newReader, err := interpolatePluginJson(reader, &pluginCommon); err != nil {
 		return err
 	} else {
 		jsonParser = json.NewDecoder(newReader)
 	}
 
-	switch pluginCommon.Type {
-	case "datasource":
-		p := DataSourcePlugin{}
-		if err := jsonParser.Decode(&p); err != nil {
-			return err
-		}
+	var loader PluginLoader
 
-		DataSources[p.Id] = &p
-		addPublicContent(&p.PluginCommon, currentDir)
-
-	case "panel":
-		p := PanelPlugin{}
-		reader.Seek(0, 0)
-		if err := jsonParser.Decode(&p); err != nil {
-			return err
-		}
-
-		Panels[p.Id] = &p
-		addPublicContent(&p.PluginCommon, currentDir)
-	case "api":
-		p := ApiPlugin{}
-		reader.Seek(0, 0)
-		if err := jsonParser.Decode(&p); err != nil {
-			return err
-		}
-		ApiPlugins[p.Id] = &p
-	case "app":
-		p := AppPlugin{}
-		reader.Seek(0, 0)
-		if err := jsonParser.Decode(&p); err != nil {
-			return err
-		}
-		Apps[p.Id] = &p
-		addPublicContent(&p.PluginCommon, currentDir)
-	default:
+	if pluginGoType, exists := PluginTypes[pluginCommon.Type]; !exists {
 		return errors.New("Unkown plugin type " + pluginCommon.Type)
+	} else {
+		loader = reflect.New(reflect.TypeOf(pluginGoType)).Interface().(PluginLoader)
 	}
 
-	return nil
+	return loader.Load(jsonParser, currentDir)
 }
 
 func GetEnabledPlugins(orgApps []*models.AppPlugin) EnabledPlugins {

pkg/plugins/plugins_test.go

@@ -19,6 +19,10 @@ func TestPluginScans(t *testing.T) {
 		So(err, ShouldBeNil)
 		So(len(DataSources), ShouldBeGreaterThan, 1)
 		So(len(Panels), ShouldBeGreaterThan, 1)
+
+		Convey("Should set module automatically", func() {
+			So(DataSources["graphite"].Module, ShouldEqual, "app/plugins/datasource/graphite/module")
+		})
 	})
 
 	Convey("When reading app plugin definition", t, func() {