Update README.md

Author: palchukovsky

README.md

@@ -4,24 +4,70 @@ A tool to read and modify Base64 encoded JSON to use configurations JSON-files f
 ## To install
 [Go](https://golang.org/dl/) has to be installed.
 ```shell
-    go get github.com/palchukovsky/json-env
+go get github.com/palchukovsky/json-env
 ```
 ## Examples
 ### Set value
 ```shell
-    json-env -source eyJmIjoidmFsMiIsIngiOnsieSI6eyJ6IjoidmFsMSJ9fX0 -write "x/y/z=1 2 3" z=valX
+json-env -source eyJmIjoidmFsMiIsIngiOnsieSI6eyJ6IjoidmFsMSJ9fX0 -write "x/y/z=1 2 3" z=valX
 ```
 ### Read value
 ```shell
-    json-env -source eyJmIjoidmFsMiIsIngiOnsieSI6eyJ6IjoiMSAyIDMifX0sInoiOiJ2YWxYIn0 -read x/y/z
-    json-env -source eyJmIjoidmFsMiIsIngiOnsieSI6eyJ6IjoiMSAyIDMifX0sInoiOiJ2YWxYIn0 -read z
-    json-env -source eyJmIjoidmFsMiIsIngiOnsieSI6eyJ6IjoiMSAyIDMifX0sInoiOiJ2YWxYIn0 -read zz -default "is not existent"
+json-env -source eyJmIjoidmFsMiIsIngiOnsieSI6eyJ6IjoiMSAyIDMifX0sInoiOiJ2YWxYIn0 -read x/y/z
+json-env -source eyJmIjoidmFsMiIsIngiOnsieSI6eyJ6IjoiMSAyIDMifX0sInoiOiJ2YWxYIn0 -read z
+json-env -source eyJmIjoidmFsMiIsIngiOnsieSI6eyJ6IjoiMSAyIDMifX0sInoiOiJ2YWxYIn0 -read zz -default "is not existent"
 ```
 ### Export source
 ```shell
-    json-env -source eyJmIjoidmFsMiIsIngiOnsieSI6eyJ6IjoiMSAyIDMifX0sInoiOiJ2YWxYIn0 -export
+json-env -source eyJmIjoidmFsMiIsIngiOnsieSI6eyJ6IjoiMSAyIDMifX0sInoiOiJ2YWxYIn0 -export
 ```
 ### Encode JSON-file to Base64
 ```shell
-    json-env -encode_file /path/config.json
+json-env -encode_file /path/config.json
+```
+### Use-case example
+```Makefile
+CONFIG ?= $(shell json-env -encode_file ./.config.json)
+AWS_APP_GATEWAY_ID := $(shell json-env -source ${CONFIG} -read service/aws/gateway/app/id)
+AWS_REGION := $(shell json-env -source ${CONFIG} -read service/aws/region)
+CONFIG := $(shell json-env -source ${CONFIG} -write \
+    "build/version=${VERSION}" \
+    "build/commit=${COMMIT}" \
+    "build/id=${BUILD}" \
+    "build/builder=${BUILDER}" \
+    "build/maintainer=${MAINTAINER}" \
+    "service/aws/gateway/app/endpoint=${AWS_APP_GATEWAY_ID}.execute-api.${AWS_REGION}.amazonaws.com/${VERSION}")
+AWS_ACCESS_KEY_ID := $(shell json-env -source ${CONFIG} -read builder/aws/accessKey/id)
+AWS_SECRET_ACCESS_KEY := $(shell json-env -source ${CONFIG} -read builder/aws/accessKey/secret)
+AWS_ACCOUNT_ID := $(shell json-env -source ${CONFIG} -read service/aws/accountId)
+AWS_AUTH_GATEWAY_ID := $(shell json-env -source ${CONFIG} -read service/aws/gateway/auth/id)
+    
+define create-config-file
+    -mkdir -p ${1}
+    @echo "json-env -source CONFIG -export > ${1}config.json"
+    @json-env -source ${CONFIG} -export > "${1}config.json"
+endef
+```
+``` go
+func newService(projectPackage string) service {
+	name := os.Args[0]
+
+	var config Config
+	{
+		file, err := ioutil.ReadFile("./lambda_config.json")
+		if err != nil {
+			log.Fatalf(`Failed to read config file: "%v".`, err)
+		}
+		if err := json.Unmarshal(file, &config); err != nil {
+			log.Fatalf(`Failed to parse config file: "%v".`, err)
+		}
+	}
+
+	return service{
+		name:   name,
+		log:    newProductLog(projectPackage, name, config),
+		config: config.Service,
+		build:  config.Build,
+	}
+}
 ```