init KV from .json file

.gitignore

@@ -0,0 +1 @@
+.idea

example/example.json

@@ -0,0 +1,4 @@
+{
+  "GONSUL" : "Hi, this is gonsul",
+  "VERSION" : "version 1.0"
+}

example/go.mod

@@ -1,3 +1,5 @@
 module example
 
-replace github.com/rajatm99/gonsul => ../../gonsul
+go 1.22.2
+
+require github.com/rajatm99/gonsul v0.0.0-00010101000000-000000000000

example/main.go

@@ -1,7 +1,21 @@
 package main
 
-import "fmt"
+import (
+	"fmt"
+	"github.com/rajatm99/gonsul/gonsul"
+	"net/http"
+	"time"
+)
 
 func main() {
-	fmt.Println("Hello World!")
+	x := gonsul.Gonsul{
+		Host: "http://localhost:8500/v1/kv",
+		Path: "gonsul",
+		File: "./example.json",
+		HttpClient: http.Client{
+			Timeout: time.Second * 30,
+		},
+	}
+	err := x.InitFromFile()
+	fmt.Println(err)
 }

gonsul/client.go

@@ -0,0 +1,74 @@
+package gonsul
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+)
+
+type consulResponse struct {
+	Value string `json:"Value"`
+}
+
+type apiParams struct {
+	method string
+	body   []byte
+}
+
+func (g Gonsul) callAPI(params apiParams) (httpResponse *http.Response, err error) {
+	request, err := http.NewRequest(params.method, fmt.Sprintf("%s/%s", g.Host, g.Path), bytes.NewBuffer(params.body))
+	if err != nil {
+		err = errUnableToCreateHttpRequest
+		return
+	}
+
+	request.Header.Set("Content-Type", "application/json")
+
+	httpResponse, err = g.HttpClient.Do(request)
+	if err != nil {
+		err = errUnableToCallConsulAPI
+	}
+	return
+}
+
+func (g Gonsul) getValues() (resp consulResponse, err error) {
+	response, err := g.callAPI(apiParams{method: http.MethodGet, body: nil})
+	if err != nil {
+		return
+	}
+	bodyBytes, err := io.ReadAll(response.Body)
+	if err != nil {
+		err = errUnableToReadConsulResponse
+		return
+	}
+
+	if len(bodyBytes) == 0 {
+		err = errConsulKeyNotFound
+		return
+	}
+	var r []consulResponse
+	err = json.Unmarshal(bodyBytes, &r)
+	if err != nil {
+		err = errUnableToReadConsulResponse
+		return
+	}
+	if len(r) > 0 {
+		return r[0], nil
+	}
+	return
+}
+
+func (g Gonsul) putValues(value []byte) (err error) {
+	response, err := g.callAPI(apiParams{method: http.MethodPut, body: value})
+	if err != nil {
+		return err
+	}
+
+	if response.StatusCode != 200 {
+		err = errConsulUpdateValueFailed
+		return
+	}
+	return
+}

gonsul/domain.go

@@ -0,0 +1,86 @@
+package gonsul
+
+import (
+	"encoding/base64"
+	"encoding/json"
+	"errors"
+	"net/http"
+	"os"
+)
+
+type Gonsul struct {
+	Host       string
+	Path       string
+	File       string
+	HttpClient http.Client
+}
+
+func (g Gonsul) InitFromFile() (err error) {
+	fileData, err := os.ReadFile(g.File)
+	if err != nil {
+		err = errFileNotFound
+		return
+	}
+
+	data := make(map[string]interface{})
+
+	err = json.Unmarshal(fileData, &data)
+	if err != nil {
+		err = errUnableToReadInputFile
+		return
+	}
+	kv, err := g.GetKV()
+	if err != nil && !errors.Is(err, errConsulKeyNotFound) {
+		return err
+	}
+
+	var flag bool
+	for k, v := range data {
+		if _, ok := kv[k]; !ok {
+			flag = true
+			kv[k] = v
+		}
+	}
+
+	if flag == true {
+		finalJSON, _err := json.MarshalIndent(data, "", "    ")
+		if _err != nil {
+			err = _err
+			return
+		}
+
+		err = g.putValues(finalJSON)
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func (g Gonsul) GetKV() (kv map[string]interface{}, err error) {
+	kv = make(map[string]interface{})
+
+	values, err := g.getValues()
+	if err != nil {
+		return
+	}
+
+	if len(values.Value) == 0 {
+		err = errValueNotFound
+	}
+
+	decodeString, err := base64.StdEncoding.DecodeString(values.Value)
+	if err != nil {
+		err = errUnableToReadConsulResponse
+		return
+	}
+
+	err = json.Unmarshal(decodeString, &kv)
+	if err != nil {
+		err = errUnableToReadConsulResponse
+		return
+	}
+
+	return
+}

gonsul/errors.go

@@ -0,0 +1,14 @@
+package gonsul
+
+import "errors"
+
+var (
+	errUnableToCreateHttpRequest  = errors.New("GONSUL_UNABLE_TO_CREATE_HTTP_REQUEST")
+	errUnableToCallConsulAPI      = errors.New("GONSUL_UNABLE_TO_CALL_CONSUL_API")
+	errUnableToReadConsulResponse = errors.New("GONSUL_UNABLE_TO_READ_CONSUL_RESPONSE")
+	errConsulKeyNotFound          = errors.New("GONSUL_CONSUL_KEY_NOT_FOUND")
+	errConsulUpdateValueFailed    = errors.New("GONSUL_CONSUL_UPDATE_VALUE_FAILED")
+	errUnableToReadInputFile      = errors.New("GONSUL_UNABLE_TO_READ_INPUT_FILE")
+	errFileNotFound               = errors.New("GONSUL_FILE_NOT_FOUND")
+	errValueNotFound              = errors.New("GONSUL_VALUE_NOT_FOUND")
+)