feat(*): uids everywhere

Converts every place a dashboard has to be identified to use the uid.
This is the only reference that is shared between Grafana and Grizzly.

.gitignore

@@ -1 +1,2 @@
 /grr
+/test

cmd/grr/main.go

@@ -11,6 +11,7 @@ import (
 var Version = "dev"
 
 func main() {
+	log.SetFlags(0)
 
 	rootCmd := &cli.Command{
 		Use:     "grr",

cmd/grr/workflow.go

@@ -49,7 +49,7 @@ func showCmd() *cli.Command {
 		if err != nil {
 			return err
 		}
-		return grizzly.Show(*config, jsonnetFile, targets)
+		return grizzly.Show(*config, jsonnetFile, *targets)
 	}
 	return cmd
 }
@@ -67,7 +67,7 @@ func diffCmd() *cli.Command {
 		if err != nil {
 			return err
 		}
-		return grizzly.Diff(*config, jsonnetFile, targets)
+		return grizzly.Diff(*config, jsonnetFile, *targets)
 	}
 	return cmd
 }
@@ -85,7 +85,7 @@ func applyCmd() *cli.Command {
 		if err != nil {
 			return err
 		}
-		return grizzly.Apply(*config, jsonnetFile, targets)
+		return grizzly.Apply(*config, jsonnetFile, *targets)
 	}
 	return cmd
 }
@@ -105,7 +105,7 @@ func watchCmd() *cli.Command {
 			return err
 		}
 
-		return grizzly.Watch(*config, watchDir, jsonnetFile, targets)
+		return grizzly.Watch(*config, watchDir, jsonnetFile, *targets)
 
 	}
 	return cmd
@@ -133,7 +133,7 @@ func previewCmd() *cli.Command {
 		if err != nil {
 			return err
 		}
-		return grizzly.Preview(*config, jsonnetFile, targets, opts)
+		return grizzly.Preview(*config, jsonnetFile, *targets, opts)
 	}
 	return cmd
 }
@@ -152,7 +152,7 @@ func exportCmd() *cli.Command {
 		if err != nil {
 			return err
 		}
-		return grizzly.Export(*config, jsonnetFile, dashboardDir, targets)
+		return grizzly.Export(*config, jsonnetFile, dashboardDir, *targets)
 	}
 	return cmd
 }

pkg/grizzly/grafana.go

@@ -9,6 +9,7 @@ import (
 	"net/http"
 	"net/url"
 	"path"
+	"strings"
 )
 
 // Folder encapsulates a folder object from the Grafana API
@@ -21,17 +22,80 @@ type Folder struct {
 // Board enscapsulates a dashboard for upload to Grafana API
 type Board struct {
 	Dashboard map[string]interface{} `json:"dashboard"`
-	FolderID  int                    `json:"folderId"`
 	Overwrite bool                   `json:"overwrite"`
-	UID       string
-	Name      string
+}
+
+func (b *Board) UnmarshalJSON(data []byte) error {
+	var m map[string]interface{}
+	if err := json.Unmarshal(data, &m); err != nil {
+		return err
+	}
+
+	delete(m, "version")
+	delete(m, "id")
+
+	b.Dashboard = m
+	return nil
+}
+
+func (b Board) UID() string {
+	if s, ok := b.Dashboard["uid"]; ok {
+		return s.(string)
+	}
+	panic("no uid")
 }
 
 // Boards encasulates a set of dashboards ready for upload
 type Boards map[string]Board
 
+func (bPtr *Boards) UnmarshalJSON(data []byte) error {
+	if *bPtr == nil {
+		*bPtr = make(Boards)
+	}
+
+	var m map[string]Board
+	if err := json.Unmarshal(data, &m); err != nil {
+		return err
+	}
+
+	// check uids missing
+	var missing ErrUidsMissing
+	for key, board := range m {
+		if _, ok := board.Dashboard["uid"]; !ok {
+			missing = append(missing, key)
+		}
+	}
+	if len(missing) > 0 {
+		return missing
+	}
+
+	for k, v := range m {
+		(*bPtr)[k] = v
+	}
+
+	// check duplicate uids
+	//           uid -> name
+	uids := make(map[string]string)
+	for name, board := range m {
+		has, exist := uids[board.UID()]
+		if exist {
+			return fmt.Errorf("UID '%s' claimed by '%s' is also used by '%s'. UIDs must be unique.", board.UID(), name, has)
+		}
+		uids[board.UID()] = name
+	}
+
+	return nil
+}
+
+type ErrUidsMissing []string
+
+func (e ErrUidsMissing) Error() string {
+	return fmt.Sprintf("One or more dashboards have no UID set. UIDs are required for Grizzly to operate properly:\n - %s", strings.Join(e, "\n - "))
+}
+
 // GetAPIJSON returns JSON expected by Grafana API
 func (b Board) GetAPIJSON() (string, error) {
+	b.Overwrite = true
 	j, err := json.MarshalIndent(b, "", "  ")
 	if err != nil {
 		return "", err
@@ -48,29 +112,6 @@ func (b Board) GetDashboardJSON() (string, error) {
 	return string(j), nil
 }
 
-func parseDashboards(raw string) (Boards, error) {
-	var boards Boards
-	if err := json.Unmarshal([]byte(raw), &boards); err != nil {
-		return nil, err
-	}
-	newBoards := make(Boards)
-	for key, board := range boards {
-		board.UID = fmt.Sprintf("%v", board.Dashboard["uid"])
-		board.Name = key
-		newBoards[key] = board
-	}
-	return newBoards, nil
-}
-
-func parseDashboard(raw string) (*Board, error) {
-	var board Board
-	if err := json.Unmarshal([]byte(raw), &board); err != nil {
-		return nil, err
-	}
-	board.UID = fmt.Sprintf("%v", board.Dashboard["uid"])
-	return &board, nil
-}
-
 func searchFolder(config Config, name string) (*Folder, error) {
 	if config.GrafanaURL == "" {
 		return nil, errors.New("Must set GRAFANA_URL environment variable")
@@ -106,7 +147,6 @@ func searchFolder(config Config, name string) (*Folder, error) {
 }
 
 func getDashboard(config Config, uid string) (*Board, error) {
-
 	if config.GrafanaURL == "" {
 		return nil, errors.New("Must set GRAFANA_URL environment variable")
 	}
@@ -116,30 +156,45 @@ func getDashboard(config Config, uid string) (*Board, error) {
 		return nil, err
 	}
 	u.Path = path.Join(u.Path, "api/dashboards/uid", uid)
+
 	resp, err := http.Get(u.String())
 	if err != nil {
 		return nil, err
 	}
 	defer resp.Body.Close()
-	body, err := ioutil.ReadAll(resp.Body)
-	if err != nil {
-		return nil, err
-	}
-	if resp.StatusCode == 404 {
+
+	switch resp.StatusCode {
+	case http.StatusNotFound:
 		return nil, ErrNotFound
+	default:
+		if resp.StatusCode >= 400 {
+			return nil, errors.New(resp.Status)
+		}
 	}
-	if resp.StatusCode >= 400 {
-		return nil, errors.New(resp.Status)
-	}
-	board, err := parseDashboard(string(body))
+
+	data, err := ioutil.ReadAll(resp.Body)
 	if err != nil {
 		return nil, err
 	}
-	return board, nil
+
+	var board Board
+	if err := json.Unmarshal(data, &board); err != nil {
+		return nil, APIErr{err, data}
+	}
+
+	return &board, nil
 }
 
-func postDashboard(config Config, board Board) error {
+type APIErr struct {
+	err  error
+	body []byte
+}
+
+func (e APIErr) Error() string {
+	return fmt.Sprintf("Failed to parse response: %s.\n\nResponse:\n%s", e.err, string(e.body))
+}
 
+func postDashboard(config Config, board Board) error {
 	if config.GrafanaURL == "" {
 		return errors.New("Must set GRAFANA_URL environment variable")
 	}
@@ -153,13 +208,29 @@ func postDashboard(config Config, board Board) error {
 	if err != nil {
 		return err
 	}
-	resp, err := http.Post(u.String(), "application/json", bytes.NewBuffer([]byte(boardJSON)))
+
+	resp, err := http.Post(u.String(), "application/json", bytes.NewBufferString(boardJSON))
 	if err != nil {
 		return err
 	}
-	if resp.StatusCode != 200 {
-		return fmt.Errorf("Non-200 response from Grafana: %s", resp.Status)
+
+	switch resp.StatusCode {
+	case http.StatusOK:
+		break
+	case http.StatusPreconditionFailed:
+		d := json.NewDecoder(resp.Body)
+		var r struct {
+			Message string `json:"message"`
+		}
+		if err := d.Decode(&r); err != nil {
+			return fmt.Errorf("Failed to decode actual error (412 Precondition failed): %s", err)
+		}
+		fmt.Println(boardJSON)
+		return fmt.Errorf("Error while applying '%s' to Grafana: %s", board.UID(), r.Message)
+	default:
+		return fmt.Errorf("Non-200 response from Grafana while applying '%s': %s", resp.Status, board.UID())
 	}
+
 	return nil
 }