restructure project

src/function.go

@@ -0,0 +1,98 @@
+package coffee
+
+import (
+	"context"
+	"encoding/json"
+	"log"
+	"net/http"
+	"os"
+
+	"cloud.google.com/go/logging"
+)
+
+type reply struct {
+	Response_type string `json:"response_type"`
+	Text          string `json:"text"`
+}
+
+type message struct {
+	Message      string `json:"message"`
+	Channel_id   string `json:"channel_id"`
+	Channel_name string `json:"channel_name"`
+	Team_domain  string `json:"team_domain"`
+	Team_id      string `json:"team_id"`
+	Post_id      string `json:"post_id"`
+	Text         string `json:"text"`
+	Timestamp    int64  `json:"timestamp"`
+	Token        string `json:"token"`
+	Trigger_word string `json:"trigger_word"`
+	User_id      string `json:"user_id"`
+	User_name    string `json:"user_name"`
+}
+
+func contains(haystack []string, needle string) bool {
+	for _, shiny := range haystack {
+		if shiny == needle {
+			return true
+		}
+	}
+	return false
+}
+
+// Coffee() replies to mattermost webhooks with the correct token value
+func Coffee(writer http.ResponseWriter, request *http.Request) {
+	project_id := os.Getenv("PROJECT_ID")
+
+	if project_id == "" {
+		log.Fatal("Environment variable PROJECT_ID is empty")
+	}
+
+	// Create cloud logging client
+	ctx := context.Background()
+	client, err := logging.NewClient(ctx, project_id)
+
+	logger := client.Logger("Coffee-log")
+	var stdlog *log.Logger
+
+	if err != nil {
+		defer client.Close()
+		stdlog = logger.StandardLogger(logging.Debug)
+	} else {
+		log.Printf("Failed to create logging client: %v", err)
+		stdlog = log.New(os.Stderr, "", log.LstdFlags)
+	}
+
+	// Load valid tokens to reply to
+	tokens := make([]string, 0)
+
+	for _, envvar := range []string{"MATTERMOST_TOKEN", "TEST_TOKEN"} {
+		token := os.Getenv(envvar)
+		if token != "" {
+			tokens = append(tokens, token)
+		} else {
+			stdlog.Printf("Environment variable %v is empty\n", token)
+		}
+	}
+
+	// Unmarshal message and reply
+	incoming := message{}
+	err = json.NewDecoder(request.Body).Decode(&incoming)
+
+	if err != nil {
+		stdlog.Printf("Failed to decode message: %v\n", err)
+		http.Error(writer, http.StatusText(http.StatusBadRequest), http.StatusBadRequest)
+		return
+	}
+
+	if !contains(tokens, incoming.Token) {
+		stdlog.Printf("Invalid request received with token %+v", incoming.Token)
+		http.Error(writer, http.StatusText(http.StatusBadRequest), http.StatusBadRequest)
+		return
+	}
+
+	err = json.NewEncoder(writer).Encode(&reply{Response_type: "comment", Text: "@omorud"})
+
+	if err != nil {
+		stdlog.Printf("Failed to encode response: %v\n", err)
+	}
+}