reorganize packages and add tests for zabbix datasource instance methods

pkg/datasource/resource_handler.go

@@ -0,0 +1,84 @@
+package datasource
+
+import (
+	"encoding/json"
+	"io/ioutil"
+	"net/http"
+
+	"github.com/grafana/grafana-plugin-sdk-go/backend/resource/httpadapter"
+)
+
+func (ds *ZabbixDatasource) RootHandler(rw http.ResponseWriter, req *http.Request) {
+	ds.logger.Debug("Received resource call", "url", req.URL.String(), "method", req.Method)
+
+	rw.Write([]byte("Hello from Zabbix data source!"))
+	rw.WriteHeader(http.StatusOK)
+}
+
+func (ds *ZabbixDatasource) ZabbixAPIHandler(rw http.ResponseWriter, req *http.Request) {
+	if req.Method != http.MethodPost {
+		return
+	}
+
+	body, err := ioutil.ReadAll(req.Body)
+	defer req.Body.Close()
+	if err != nil || len(body) == 0 {
+		writeError(rw, http.StatusBadRequest, err)
+		return
+	}
+
+	var reqData ZabbixAPIResourceRequest
+	err = json.Unmarshal(body, &reqData)
+	if err != nil {
+		ds.logger.Error("Cannot unmarshal request", "error", err.Error())
+		writeError(rw, http.StatusInternalServerError, err)
+		return
+	}
+
+	pluginCxt := httpadapter.PluginConfigFromContext(req.Context())
+	dsInstance, err := ds.GetDatasource(pluginCxt)
+	if err != nil {
+		ds.logger.Error("Error loading datasource", "error", err)
+		writeError(rw, http.StatusInternalServerError, err)
+		return
+	}
+
+	apiReq := &ZabbixAPIRequest{Method: reqData.Method, Params: reqData.Params}
+
+	result, err := dsInstance.ZabbixAPIQuery(req.Context(), apiReq)
+	if err != nil {
+		ds.logger.Error("Zabbix API request error", "error", err)
+		writeError(rw, http.StatusInternalServerError, err)
+		return
+	}
+
+	writeResponse(rw, result)
+}
+
+func writeResponse(rw http.ResponseWriter, result *ZabbixAPIResourceResponse) {
+	resultJson, err := json.Marshal(*result)
+	if err != nil {
+		writeError(rw, http.StatusInternalServerError, err)
+	}
+
+	rw.Header().Add("Content-Type", "application/json")
+	rw.WriteHeader(http.StatusOK)
+	rw.Write(resultJson)
+}
+
+func writeError(rw http.ResponseWriter, statusCode int, err error) {
+	data := make(map[string]interface{})
+
+	data["error"] = "Internal Server Error"
+	data["message"] = err.Error()
+
+	var b []byte
+	if b, err = json.Marshal(data); err != nil {
+		rw.WriteHeader(statusCode)
+		return
+	}
+
+	rw.Header().Add("Content-Type", "application/json")
+	rw.WriteHeader(http.StatusInternalServerError)
+	rw.Write(b)
+}