Documentation/rest api web

doc/news/_preparation_next_release.md

@@ -321,6 +321,7 @@ The following section lists news about the [modules](https://www.libelektra.org/
 ### Reference
 
 - Fixed missing Metadata in README and METADATA.ini. _(Michael Zronek)_
+- Update README.md web tool to show, how to test REST API on localhost. _(Dmytro Moiseiuk)_
 
 ### Specload
 
@@ -445,7 +446,7 @@ you up to date with the multi-language support provided by Elektra.
 - JNA is now not experimental anymore. _(Markus Raab)_
 - gsettings is not default anymore. _(Markus Raab)_
 
-- Add fix for creating the Key and KeySet objects in the HelloElektra.java file _(Dmytro Moiseiuk)_
+- Add fix for creating the Key and KeySet objects in the HelloElektra.java file. _(Dmytro Moiseiuk)_
 - We fixed a [warning about a deprecated default constructor](https://issues.libelektra.org/2670) in the C++ binding reported by GCC 9.0. _(René Schwaiger)_
 - <<TODO>>
 

src/tools/web/README.md

@@ -114,6 +114,67 @@ Elektra web consists of multiple components:
 - [elektrad](https://master.libelektra.org/doc/api_blueprints/elektrad.apib), documentation: https://elektrad.docs.apiary.io/
 - [webd](https://master.libelektra.org/doc/api_blueprints/webd.apib), documentation: https://elektrawebd.docs.apiary.io/
 
+## Test REST API on localhost
+
+In order to test API on localhost, you have to start elektrad instance. You can do it in two ways:
+
+- run manually (if you would like to start it manually or you don't have eletrad-web tool installed)
+
+  - `cd libelektra/src/tools/web`
+  - `cd elektrad`
+  - `npm install`
+  - `npm start`
+
+- by installing elektrad tool together with Elektra and run it
+  - please see the section `Building with elektra-web Tool`
+
+Now the server is runing on [http://localhost:33333](http://localhost:33333). After that you can test API with help of Postman or other tool, which allows to send REST API requests.
+
+Additional note. It is recommended to install the elektrad tool than starting the server manually.
+When Elektra is installed, the `kdb` command together with its tools is installed globally.
+For instance, whenever you would like to write any shell script, which has to start a REST API server, you can just add the following line `kdb run-elektrad` inside your file and save it.
+After that, the created shell script can be executed from any directory.
+
+Examples:
+
+let's create the new key-value pair `user/test` and set its value to 5. You can do it next way:
+
+- through the command terminal
+  ```sh
+  kdb set user/test 5
+  ```
+- through the rest api using curl
+  ```sh
+  curl -X PUT -H "Content-Type: text/plain" --data "5" http://localhost:33333/kdb/user/test
+  ```
+
+The output of any of two commands will be: `Set string to "5"`. If the specified key didn't exist before, then the output will be `Create a new key user/test with string "5"`.
+
+Now, the command
+
+```sh
+curl http://localhost:33333/kdb/user/test
+```
+
+will return us the value of the specified key `user/test`, which is stored in the database right now
+
+<!-- prettier-ignore-start -->
+
+```json
+{
+    "exists": true,
+    "name": "test",
+    "path": "user/test",
+    "ls": [
+        "user/test"
+    ],
+    "value": "5",
+    "meta": ""
+}
+```
+
+<!-- prettier-ignore-end -->
+
 ## Auth
 
 Currently, webd does not support authentication. The best way to work around