Rest API testing using Rest-Assured Java Framework

• This is repository of basic REST API testing framework
• The public API used for this example is - https://restful-booker.herokuapp.com
• This framework is developed using Rest-Assured library for Rest API testing
• For JSON Parsing in java the library used is - json-simple and Jackson API
• Reporting is by Allure API

Below are instructions are how to create Rest API test framework using Rest Assured Java library

• Maven Dependency to add,
	<dependency>
	    <groupId>io.rest-assured</groupId>
	    <artifactId>rest-assured</artifactId>
	    <version>3.3.0</version>
	    <scope>test</scope>
	</dependency>
	
• RestAssured.uri = "" // to specify the basic URL of the API

• Basic building blocks of Rest Assured - given, when, then

• Values that can be provided in the given block,
	○ 
• To print the response body as string,
	```
	@Test
	public void RESTAutomation() {
		RestAssured.baseURI="http://api.zippopotam.us";
		RequestSpecification requestSpecification = given();
		Response response = requestSpecification.when().get("/us/10094");
		System.out.println(response.asString());
		System.out.println(response.then().extract().response().asString());
	}
	```
• To specify particular header value when sending the request
	Header header = new Header("key","value");
	RequestSpecification requestSpecification = given().header(header);
			
• To validate response content type,
	○ response.then().contentType(ContentType.JSON);

• To get a cookie value,
	○ System.out.println(response.getCookie("__cfduid").toString());

• To get log when response is being fetched,
	○ response.then().log().all();

• To validate a particular item from the response body,
	○ REST-assured takes advantage of the power of Hamcrest matchers to perform its assertions,
	○ If equalTo is not getting detected, add this import 'import static org.hamcrest.Matchers.equalTo;'
	○ response.then().assertThat().body("places[0].'place name'", equalTo("New York City"));
	○ response.then().assertThat().body("places.'place name'", hasItem("New York City")); //to verify when array of objects are present of a particular value is present in any of the objects under the array in the given item
	○ response.then().assertThat().body("places.'place name'", hasSize(1)); // To check how many items are present in a array collection inside the json
	
• Validating status code before every test run using ResponseBuilder
	    public static ResponseSpecBuilder builder;
	    public static ResponseSpecification responseSpec;
	    @BeforeClass
	    public static void setupResponseSpecBuilder()
	    {
	        builder = new ResponseSpecBuilder();
	        builder.expectStatusCode(200);
	        responseSpec = builder.build();
	    }
		
		@Test
		public void RESTAutomation() {
			RestAssured.baseURI="http://api.zippopotam.us";
			Header header = new Header("key","value");
			RequestSpecification requestSpecification = given().header(header);
			Response response = requestSpecification.when().get("/us/90210");
			response.then().spec(responseSpec);

• RequestBuilder to specify header or login details
	    public static RequestSpecBuilder builder;
	    public static RequestSpecification requestSpec;
	    @BeforeClass
	    public static void setupRequestSpecBuilder()
	    {
	        builder = new RequestSpecBuilder();
	        builder.addHeader("Authorization", "abcd-123-xyz");
	        builder.addParameter("loginID", "joebloggs");
	        requestSpec = builder.build();
	    }
	
	@Test
	public void testAnApiPostCall()
	{
	    given().
	        spec(requestSpec).

• Traversing:
	○ REST Assured uses JsonPath/GPath and XmlPath 

• Schema Validation:
	○ get("/products").then().assertThat().body(matchesJsonSchemaInClasspath("products-schema.json").using(settings().with().checkedValidation(false)));

• JAX-RX from Java to be used to develop APIs

• Path and Query Parameters
	○ http://localhost:8081/SearchApp/book?name=java => QueryParameter
	○ http://localhost:8081/SearchApp/book/java => PathParameter
	
		§ Using pathParams
			□ Given().pathParam("key","value")
			□ When().get("//us/{key}/repose")
			□ Then.statusCode(200)
		§ Using Query parameters,
			□ Given().queryParam("key","value")  or Given().param("key","value")
			□ When().get("/us/target")
			□ Then.statusCode(200)

Deserializing JSON response:

• Using getters and setters of POJO classes, serialisation and deserialization of JSON objects can be made simple
	○ To convert a normal java class to POJO => provide the field names, ALT+SHIFT+S, generate getter and setter
• We can use JacksonAPI to easily work with json objects and below are the dependencies to be added,
	<dependency>
	    <groupId>com.fasterxml.jackson.core</groupId>
	    <artifactId>jackson-databind</artifactId>
	    <version>2.9.8</version>
	</dependency>
	
	<!-- https://mvnrepository.com/artifact/com.fasterxml.jackson.core/jackson-core -->
	<dependency>
	    <groupId>com.fasterxml.jackson.core</groupId>
	    <artifactId>jackson-core</artifactId>
	    <version>2.9.8</version>
	</dependency>
	
	<!-- https://mvnrepository.com/artifact/com.fasterxml.jackson.core/jackson-annotations -->
	<dependency>
	    <groupId>com.fasterxml.jackson.core</groupId>
	    <artifactId>jackson-annotations</artifactId>
	    <version>2.9.8</version>
	</dependency>

• In the pojo class, each class variables to be annotated with @JSONProperty. If left default the variable name is equal to JSON property name.  If we mention it as "@JSONProperty("name")" then the name mentioned here corresponds to the json object property name
• Now to convert the json response into an object of POJO class, use 'response.as(ClassName.class)' after obtaining the response normally
	○ e.g. 
	BookingDetails bookingDetails = response.as(BookingDetails.class);
	System.out.println("Additional Details are : "+bookingDetails.getAdditionalneeds());