Rejecting Undesired Requests

Rest API (Without Stealth)

You can use rejectResourceTypes and rejectRequestPattern to block undesired content, resources and requests.

Bot detection

Browserless recommends using our REST API to take screenshots, unless you need to get past bot detectors.

JSON payload

// Will reject any images and .css files
{
  "url": "https://browserless.io/"
  "rejectResourceTypes": ["image"],
  "rejectRequestPattern": ["/^.*\\.(css)"]
}

cURL

curl -X POST \
  https://production-sfo.browserless.io/screenshot?token=YOUR_API_TOKEN_HERE \
  -H 'Cache-Control: no-cache' \
  -H 'Content-Type: application/json' \
  -d '{
  "url": "https://browserless.io/",
  "rejectResourceTypes": ["image"],
  "rejectRequestPattern": ["/^.*\\.(css)"]
}' \
  --output "screenshot.png"

Javascript

import fs from 'fs/promises';

const TOKEN = "YOUR_API_TOKEN_HERE";
const url = `https://production-sfo.browserless.io/screenshot?token=${TOKEN}`;
const headers = {
  "Cache-Control": "no-cache",
  "Content-Type": "application/json"
};

const data = {
  url: "https://browserless.io/",
  rejectResourceTypes: ["image"],
  rejectRequestPattern: ["^.*\\.(css)"]
};

const takeScreenshot = async () => {
  const response = await fetch(url, {
    method: 'POST',
    headers: headers,
    body: JSON.stringify(data)
  });

  const imageBuffer = await response.arrayBuffer();
  await fs.writeFile("screenshot.png", Buffer.from(imageBuffer));
  console.log("Screenshot saved as screenshot.png");
};

takeScreenshot();

Python

import requests

TOKEN = "YOUR_API_TOKEN_HERE"
url = f"https://production-sfo.browserless.io/screenshot?token={TOKEN}"
headers = {
    "Cache-Control": "no-cache",
    "Content-Type": "application/json"
}

data = {
    "url": "https://browserless.io/",
    "rejectResourceTypes": ["image"],
    "rejectRequestPattern": ["^.*\\.(css)"]
}

response = requests.post(url, headers=headers, json=data)

with open("screenshot.png", "wb") as file:
    file.write(response.content)

print("Screenshot saved as screenshot.png")

Java

import java.io.*;
import java.net.URI;
import java.net.http.*;
import java.nio.file.*;

public class TakeScreenshotWithRejections {
    public static void main(String[] args) {
        String TOKEN = "YOUR_API_TOKEN_HERE";
        String url = "https://production-sfo.browserless.io/screenshot?token=" + TOKEN;

        String jsonData = """
        {
            "url": "https://browserless.io/",
            "rejectResourceTypes": ["image"],
            "rejectRequestPattern": ["^.*\\\\.(css)"]
        }
        """;

        HttpClient client = HttpClient.newHttpClient();

        HttpRequest request = HttpRequest.newBuilder()
            .uri(URI.create(url))
            .header("Cache-Control", "no-cache")
            .header("Content-Type", "application/json")
            .POST(HttpRequest.BodyPublishers.ofString(jsonData))
            .build();

        try {
            HttpResponse<InputStream> response = client.send(request, HttpResponse.BodyHandlers.ofInputStream());
            Files.copy(response.body(), Paths.get("screenshot.png"), StandardCopyOption.REPLACE_EXISTING);
            System.out.println("Screenshot saved as screenshot.png");
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

C#

  using System;
  using System.IO;
  using System.Net.Http;
  using System.Text;
  using System.Threading.Tasks;

  class Program
  {
      static async Task Main(string[] args)
      {
          string TOKEN = "YOUR_API_TOKEN_HERE";
          string url = $"https://production-sfo.browserless.io/screenshot?token={TOKEN}";

          string jsonData = @"
            {
                ""url"": ""https://browserless.io/"",
                ""rejectResourceTypes"": [""image""],
                ""rejectRequestPattern"": [""^.*\\\\.(css)""]
            }";

          using var client = new HttpClient();

          
          var request = new HttpRequestMessage(HttpMethod.Post, url)
          {
              Content = new StringContent(jsonData, Encoding.UTF8, "application/json")
          };

          
          request.Headers.Add("Cache-Control", "no-cache");

          try
          {
              var response = await client.SendAsync(request);
              response.EnsureSuccessStatusCode();

              var imageBytes = await response.Content.ReadAsByteArrayAsync();

              await File.WriteAllBytesAsync("screenshot.png", imageBytes);

              Console.WriteLine("Screenshot saved as screenshot.png");
          }
          catch (Exception ex)
          {
              Console.WriteLine($"Error: {ex.Message}");
          }
      }
  }

BQL (Stealth)

If the /screenshot API is getting blocked by bot detectors, then we would recommend trying BrowserQL.

BQL Query

mutation Screenshot {
  reject(type: [image, stylesheet]) {
    enabled
    time
  }
  
  goto(url: "https://browserless.io/") {
    status
  }

  screenshot(type: webp) {
    base64
  }
}

cURL

curl --request POST \
  --url 'https://production-sfo.browserless.io/chromium/bql?token=YOUR_API_TOKEN_HERE' \
  --header 'Content-Type: application/json' \
  --data '{"query":"mutation Screenshot {\n  reject(type: [image, stylesheet]) {\n    enabled\n    time\n  }\n  \n  goto(url: \"https://browserless.io/\") {\n    status\n  }\n\n  screenshot(type: webp) {\n    base64\n  }\n}","variables":"","operationName":"Screenshot"}'

Javascript

const endpoint = "https://production-sfo.browserless.io/chromium/bql";
const token = "YOUR_API_TOKEN_HERE";

const options = {
  method: 'POST',
  headers: {
    'Content-Type': 'application/json',
  },
  body: JSON.stringify({"query":"mutation Screenshot {\n  reject(type: [image, stylesheet]) {\n    enabled\n    time\n  }\n  \n  goto(url: \"https://browserless.io/\") {\n    status\n  }\n\n  screenshot(type: webp) {\n    base64\n  }\n}","variables":"","operationName":"Screenshot"})
};

const url = `${endpoint}?token=${token}`;
const response = await fetch(url, options);
const data = await response.json();

console.log(data);

Python

import requests

endpoint = "https://production-sfo.browserless.io/chromium/bql"
query_string = {
    "token": "YOUR_API_TOKEN_HERE",
}
headers = {
    "Content-Type": "application/json",
}
payload = {
    "query": "mutation Screenshot {\n  reject(type: [image, stylesheet]) {\n    enabled\n    time\n  }\n  \n  goto(url: \"https://browserless.io/\") {\n    status\n  }\n\n  screenshot(type: webp) {\n    base64\n  }\n}",
    "variables": None,
    "operationName": "Screenshot",
}

response = requests.post(endpoint, params=query_string, headers=headers, json=payload)
print(response.json())

Java

String url = "https://production-sfo.browserless.io/chromium/bql";
String token = "YOUR_API_TOKEN_HERE";
String endpoint = String.format("%s?token=%s%s%s", url, token);

HttpResponse<String> response = Unirest.post(endpoint)
    .header("Content-Type", "application/json")
    .body({"query":"mutation Screenshot {\n  reject(type: [image, stylesheet]) {\n    enabled\n    time\n  }\n  \n  goto(url: \"https://browserless.io/\") {\n    status\n  }\n\n  screenshot(type: webp) {\n    base64\n  }\n}","variables":"","operationName":"Screenshot"})
    .asString();

C#

string url = "https://production-sfo.browserless.io/chromium/bql";
string token = "YOUR_API_TOKEN_HERE";
string endpoint = $"{url}?token={token}";

var payload = new
{
    query = @"mutation Screenshot {
  reject(type: [image, stylesheet]) {
    enabled
    time
  }
  
  goto(url: ""https://browserless.io/"") {
    status
  }

  screenshot(type: webp) {
    base64
  }
}",
    variables = "",
    operationName = "Screenshot"
};

using (HttpClient client = new HttpClient())
{
    var jsonPayload = System.Text.Json.JsonSerializer.Serialize(payload);
    var content = new StringContent(jsonPayload, Encoding.UTF8, "application/json");

    var response = await client.PostAsync(endpoint, content);
    string responseBody = await response.Content.ReadAsStringAsync();
    
    Console.WriteLine(responseBody);
}

BQL Schemas

For more details on BQL mutations, refer to the BrowserQL Schema reference pages.