Send custom HTTP headers in Java with OkHTTP

In this guide, we'll show you how to send custom HTTP headers when converting HTML to PDF using Java and the OkHTTP library.

When converting HTML to PDF, you might need to send custom HTTP headers to access protected resources or provide additional information.

import okhttp3.*;
import java.io.IOException;

// You can get an API key at https://pdfshift.io
String apiKey = "sk_xxxxxxxxxxxx";

OkHttpClient client = new OkHttpClient();

RequestBody body = RequestBody.create(
    "{\n" +
    "  \"source\": \"https://www.example.com\",\n" +
    "  \"headers\": {\n" +
    "    \"authorization\": \"Bearer token123\",\n" +
    "    \"user-agent\": \"MyApp/1.0\"\n" +
    "  }\n" +
    "}", MediaType.parse("application/json"));

Request request = new Request.Builder()
    .url("https://api.pdfshift.io/v3/convert/pdf")
    .addHeader("X-API-Key", apiKey)
    .post(body)
    .build();

try (Response response = client.newCall(request).execute()) {
    
    // Handle errors:
    if (!response.isSuccessful()) {
        throw new IOException("Request failed with status code " + response.code());
    }
    
    ResponseBody responseBody = response.body();
    if (responseBody != null) {
        java.nio.file.Files.write(
            java.nio.file.Paths.get("result.pdf"), 
            responseBody.bytes()
        );
    }
    
    System.out.println("The PDF document was generated and saved to result.pdf");
}

This allows you to customize the HTTP requests sent to the source URL.

For further details on the headers property and its usage, please refer to our dedicated documentation.

We hope this guide was helpful. If you have any questions or noticed any issues on the code above,
feel free to drop us a line.