Writing response into a JSON file

Rest Assured provides below methods to get a response as:-

1. As byte array :- asByteArray()
2. As input stream :- asInputStream()
3. As string :- asString()

All the above methods output can be used to write into a JSON file.

Example program

import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import com.google.common.io.Files;
 
import io.restassured.RestAssured;
import io.restassured.http.ContentType;
import io.restassured.response.Response;
import io.restassured.specification.RequestSpecification;
 
public class WriteResponseInTextFile {
 
	public static void main(String[] args) throws IOException {
 
		// There is no need to add escape character manually. Just paste string within
		// double
		// quotes. It will automatically add escape sequence as required.
		String jsonString = "{\"username\" : \"admin\",\"password\" : \"password123\"}";
 
		// Create a request specification
		RequestSpecification request = RestAssured.given();
 
		// Setting content type to specify format in which request payload will be sent.
		// ContentType is an ENUM.
		request.contentType(ContentType.JSON);
		// Adding URI
		request.baseUri("https://restful-booker.herokuapp.com/auth");
		// Adding body as string
		request.body(jsonString);
 
		// Calling POST method on URI. After hitting we get Response
		Response response = request.post();
 
		// Getting response as a string and writing in to a file
		String responseAsString = response.asString();
		// Converting in to byte array before writing
		byte[] responseAsStringByte = responseAsString.getBytes();
		// Creating a target file
		File targetFileForString = new File("src/main/resources/targetFileForString.json");
		// Writing into files
		Files.write(responseAsStringByte, targetFileForString);
 
		// Getting response as input stream and writing in to a file
		InputStream responseAsInputStream = response.asInputStream();
		// Creating a byte array with number of bytes of input stream (available()
		// method)
		byte[] responseAsInputStreamByte = new byte[responseAsInputStream.available()];
		// Reads number of bytes from the input stream and stores them into the byte
		// array responseAsInputStreamByte.
		responseAsInputStream.read(responseAsInputStreamByte);
		// Creating a target file
		File targetFileForInputStream = new File("src/main/resources/targetFileForInputStream.json");
		// Writing into files
		Files.write(responseAsInputStreamByte, targetFileForInputStream);
 
		// Directly getting a byte array
		byte[] responseAsByteArray = response.asByteArray();
		// Creating a target file
		File targetFileForByteArray = new File("src/main/resources/targetFileForByteArray.json");
		// Writing into files
		Files.write(responseAsByteArray, targetFileForByteArray);
 
	}
 
}

Output

Refresh the project folder if you are using Eclipse. You should see three files as below:-

Open a file you should see it has stored response as below:-

You may be thinking about which way is more optimal if you want to write into a file. If you notice that we get a response as String or inputStream, we just need to convert them to Byte array before writing into a file. In the third way, we are directly getting Byte Array. Hence the third way is more optimal.