-

-

datasource/controller/controller.go

@@ -0,0 +1,71 @@
+package controller
+
+import (
+	"bytes"
+	"encoding/json"
+	"io"
+	"net/http"
+	"strconv"
+
+	"datasource/store"
+)
+
+type Controller struct {
+	store *store.Store
+}
+
+func NewController(store *store.Store) *Controller {
+	return &Controller{store: store}
+}
+
+func (c *Controller) GetMetrics(w http.ResponseWriter, r *http.Request) {
+	query := r.URL.Query()
+
+	service := query.Get("service")
+	if service == "" {
+		http.Error(w, "service cannot be empty", http.StatusBadRequest)
+		return
+	}
+
+	t0, err := strconv.ParseInt(query.Get("t0"), 10, 64)
+	if err != nil {
+		http.Error(w, err.Error(), http.StatusBadRequest)
+		return
+	}
+
+	t1, err := strconv.ParseInt(query.Get("t1"), 10, 64)
+	if err != nil {
+		http.Error(w, err.Error(), http.StatusBadRequest)
+		return
+	}
+
+	if t0 > t1 {
+		http.Error(w, "t0 cannot be larger than t1", http.StatusBadRequest)
+		return
+	}
+
+	metrics, err := c.store.GetMetrics(r.Context(), service, t0, t1)
+	if err != nil {
+		// todo (david): log internal server error
+		http.Error(w, err.Error(), http.StatusInternalServerError)
+		return
+	}
+
+	var buf bytes.Buffer
+
+	if err := json.NewEncoder(&buf).Encode(metrics); err != nil {
+		// todo (david): log internal server error
+		http.Error(w, err.Error(), http.StatusInternalServerError)
+		return
+	}
+
+	w.Header().Set("Content-Type", "application/json")
+
+	if _, err := io.Copy(w, &buf); err != nil {
+		// too late to return http.StatusInternalServerError
+		// todo (david): log internal server error
+	}
+}
+
+// todo (david)
+// func (c *Controller) DeleteMetrics(w http.ResponseWriter, r *http.Request) {}