Adds poc code for retrieving google auth accesstoken

pkg/api/pluginproxy/ds_proxy.go

@@ -2,7 +2,7 @@ package pluginproxy
 
 import (
 	"bytes"
-	"encoding/json"
+	"context"
 	"errors"
 	"fmt"
 	"io/ioutil"
@@ -22,6 +22,7 @@ import (
 	"github.com/grafana/grafana/pkg/plugins"
 	"github.com/grafana/grafana/pkg/setting"
 	"github.com/grafana/grafana/pkg/util"
+	"golang.org/x/oauth2/jwt"
 )
 
 var (
@@ -353,49 +354,64 @@ func (proxy *DataSourceProxy) applyRoute(req *http.Request) {
 }
 
 func (proxy *DataSourceProxy) getAccessToken(data templateData) (string, error) {
-	if cachedToken, found := tokenCache[proxy.getAccessTokenCacheKey()]; found {
-		if cachedToken.ExpiresOn.After(time.Now().Add(time.Second * 10)) {
-			logger.Info("Using token from cache")
-			return cachedToken.AccessToken, nil
-		}
+	conf := jwt.Config{
+		Email:      "raintank-production-stackdrive@raintank-production.iam.gserviceaccount.com",
+		PrivateKey: []byte("-----BEGIN PRIVATE KEY-----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\nyA+63fAHMAwG+k22IkBqcu4=\n-----END PRIVATE KEY-----\n"),
+		Scopes:     []string{"https://www.googleapis.com/auth/monitoring.read"},
+		TokenURL:   "https://oauth2.googleapis.com/token",
 	}
-
-	urlInterpolated, err := interpolateString(proxy.route.TokenAuth.Url, data)
+	ctx := context.Background()
+	tokenSrc := conf.TokenSource(ctx)
+	// logger.Info("Accesstoken", tokenSrc.Token.AccessToken)
+	token, err := tokenSrc.Token()
 	if err != nil {
-		return "", err
-	}
-
-	params := make(url.Values)
-	for key, value := range proxy.route.TokenAuth.Params {
-		interpolatedParam, err := interpolateString(value, data)
-		if err != nil {
-			return "", err
-		}
-		params.Add(key, interpolatedParam)
+		logger.Info("GetToken", "Error", err)
 	}
-
-	getTokenReq, _ := http.NewRequest("POST", urlInterpolated, bytes.NewBufferString(params.Encode()))
-	getTokenReq.Header.Add("Content-Type", "application/x-www-form-urlencoded")
-	getTokenReq.Header.Add("Content-Length", strconv.Itoa(len(params.Encode())))
-
-	resp, err := client.Do(getTokenReq)
-	if err != nil {
-		return "", err
-	}
-
-	defer resp.Body.Close()
-
-	var token jwtToken
-	if err := json.NewDecoder(resp.Body).Decode(&token); err != nil {
-		return "", err
-	}
-
-	expiresOnEpoch, _ := strconv.ParseInt(token.ExpiresOnString, 10, 64)
-	token.ExpiresOn = time.Unix(expiresOnEpoch, 0)
-	tokenCache[proxy.getAccessTokenCacheKey()] = &token
-
-	logger.Info("Got new access token", "ExpiresOn", token.ExpiresOn)
+	logger.Info("GetToken", "Token", token.AccessToken)
 	return token.AccessToken, nil
+	// if cachedToken, found := tokenCache[proxy.getAccessTokenCacheKey()]; found {
+	// 	if cachedToken.ExpiresOn.After(time.Now().Add(time.Second * 10)) {
+	// 		logger.Info("Using token from cache")
+	// 		return cachedToken.AccessToken, nil
+	// 	}
+	// }
+
+	// urlInterpolated, err := interpolateString(proxy.route.TokenAuth.Url, data)
+	// if err != nil {
+	// 	return "", err
+	// }
+
+	// params := make(url.Values)
+	// for key, value := range proxy.route.TokenAuth.Params {
+	// 	interpolatedParam, err := interpolateString(value, data)
+	// 	if err != nil {
+	// 		return "", err
+	// 	}
+	// 	params.Add(key, interpolatedParam)
+	// }
+
+	// getTokenReq, _ := http.NewRequest("POST", urlInterpolated, bytes.NewBufferString(params.Encode()))
+	// getTokenReq.Header.Add("Content-Type", "application/x-www-form-urlencoded")
+	// getTokenReq.Header.Add("Content-Length", strconv.Itoa(len(params.Encode())))
+
+	// resp, err := client.Do(getTokenReq)
+	// if err != nil {
+	// 	return "", err
+	// }
+
+	// defer resp.Body.Close()
+
+	// var token jwtToken
+	// if err := json.NewDecoder(resp.Body).Decode(&token); err != nil {
+	// 	return "", err
+	// }
+
+	// expiresOnEpoch, _ := strconv.ParseInt(token.ExpiresOnString, 10, 64)
+	// token.ExpiresOn = time.Unix(expiresOnEpoch, 0)
+	// tokenCache[proxy.getAccessTokenCacheKey()] = &token
+
+	// logger.Info("Got new access token", "ExpiresOn", token.ExpiresOn)
+	// return token.AccessToken, nil
 }
 
 func (proxy *DataSourceProxy) getAccessTokenCacheKey() string {