Add feature to hold configs in filesystem

This patch adds feature to hold config files
on filesystem and adds all unit tests to have
enough coverage for milestones.

Change-Id: Icd6f3dc93e0f419500f82f0a6ccd62e500dfc918
Issue-ID: MUSIC-42
Signed-off-by: Shashank Kumar Shankar <shashank.kumar.shankar@intel.com>

1 files changed, 153 insertions, 0 deletions

diff --git a/src/dkv/api/utils.go b/src/dkv/api/utils.go
new file mode 100644
index 0000000..c1094ab
--- /dev/null
+++ b/src/dkv/api/utils.go
@@ -0,0 +1,153 @@
+/*
+ * Copyright 2018 Intel Corporation, Inc
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package api
+
+import (
+	"encoding/json"
+	"errors"
+	"io/ioutil"
+	"net/http"
+)
+
+var (
+	IoutilRead  = ioutil.ReadFile
+	IoutilWrite = ioutil.WriteFile
+	JsonReader  = ReadJSON
+)
+
+type Token_service_map struct {
+	Token   string `json:"token"`
+	Service string `json:"service"`
+}
+
+func ReadJSON(path string) ([]Token_service_map, error) {
+	var tsm_list []Token_service_map
+	// raw, err := ioutil.ReadFile("./token_service_map.json")
+	raw, err := IoutilRead(path)
+	if err != nil {
+		return tsm_list, err
+	}
+	json.Unmarshal(raw, &tsm_list)
+	return tsm_list, nil
+}
+
+func WriteJSON(path string, token string, service string) error {
+	tsm_list, err := JsonReader(path)
+	if err != nil {
+		return err
+	}
+	var tsm Token_service_map
+	tsm.Token = token
+	tsm.Service = service
+	tsm_list = append(tsm_list, tsm)
+	raw, err := json.Marshal(tsm_list)
+	if err != nil {
+		return err
+	}
+	err = IoutilWrite(path, raw, 0644)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+func DeleteInJSON(path string, token string) error {
+	serviceList, err := JsonReader(path)
+	if err != nil {
+		return err
+	}
+
+	var resultList []Token_service_map
+	var foundFlag = false
+
+	// Linear search for the token. If found set found flag. If not, keep
+	// copying the different values to resultList.
+	for _, service := range serviceList {
+		if service.Token == token {
+			foundFlag = true
+		} else {
+			resultList = append(resultList, service)
+		}
+	}
+
+	if foundFlag == false {
+		return errors.New("Service not found. Check if Token is correct or service is registered.")
+	} else {
+		// This is done to avoid writing 'null' in the json file.
+		if len(serviceList) == 1 {
+			dummy := Token_service_map{Token: "", Service: ""}
+			resultList = append(resultList, dummy)
+		}
+		raw, err := json.Marshal(resultList)
+		if err != nil {
+			return err
+		}
+		err = IoutilWrite(path, raw, 0644)
+		if err != nil {
+			return err
+		}
+		return nil
+	}
+}
+
+func FindTokenInJSON(path string, token string) (bool, error) {
+	serviceList, err := JsonReader(path)
+	if err != nil {
+		return false, err
+	}
+
+	for _, service := range serviceList {
+		if service.Token == token {
+			return true, nil
+		}
+	}
+	return false, nil
+}
+
+func FindServiceInJSON(path string, serviceName string) (bool, error) {
+	serviceList, err := JsonReader(path)
+	if err != nil {
+		return false, err
+	}
+
+	for _, service := range serviceList {
+		if service.Service == serviceName {
+			return true, nil
+		}
+	}
+	return false, nil
+}
+
+func GetServicebyToken(path string, token string) (string, bool, error) {
+	serviceList, err := JsonReader(path)
+	if err != nil {
+		return "", false, err
+	}
+	for _, service := range serviceList {
+		if service.Token == token {
+			return service.Service, true, nil
+		}
+	}
+	return "", false, nil
+}
+
+func GenerateResponse(w http.ResponseWriter, r *http.Request, httpStatus int, msg string) {
+	req := ResponseStringStruct{Response: msg}
+	w.Header().Set("Content-Type", "application/json")
+	w.WriteHeader(httpStatus)
+	json.NewEncoder(w).Encode(req)
+}