import os
import requests # pip install requests

# The authentication key (API Key).
# Get your own by registering at https://app.pdf.co
API_KEY = "******************************************"

# Base URL for PDF.co Web API requests
BASE_URL = "https://api.pdf.co/v1"

# Result file name
ResultFile = ".\\barcode.png"
# Barcode type. See valid barcode types in the documentation https://developer.pdf.co
BarcodeType = "Code128"
# Barcode value
BarcodeValue = "qweasd123456"


def main(args = None):
    generateBarcode(ResultFile)

def generateBarcode(destinationFile):
    """Generates Barcode using PDF.co Web API"""

    # Prepare requests params as JSON
    # See documentation: https://developer.pdf.co/api/barcode-generator
    parameters = {}
    parameters["name"] = os.path.basename(destinationFile)
    parameters["type"] = BarcodeType
    parameters["value"] = BarcodeValue

    # Prepare URL for 'Barcode Generate' API request
    url = "{}/barcode/generate".format(BASE_URL)

    # Execute request and get response as JSON
    response = requests.post(url, data=parameters, headers={ "x-api-key": API_KEY })
    if (response.status_code == 200):
        json = response.json()

        if json["error"] == False:
            #  Get URL of result file
            resultFileUrl = json["url"]
            # Download result file
            r = requests.get(resultFileUrl, stream=True)
            if (r.status_code == 200):
                with open(destinationFile, 'wb') as file:
                    for chunk in r:
                        file.write(chunk)
                print(f"Result file saved as \"{destinationFile}\" file.")
            else:
                print(f"Request error: {response.status_code} {response.reason}")
        else:
            # Show service reported error
            print(json["message"])
    else:
        print(f"Request error: {response.status_code} {response.reason}")

if __name__ == '__main__':
    main()

using System;
using System.Collections.Generic;
using System.IO;
using System.Net;
using Newtonsoft.Json;
using Newtonsoft.Json.Linq;

namespace PDFCOWebApiExample
{
  class Program
  {
    // The authentication key (API Key).
    // Get your own by registering at https://app.pdf.co
    const String API_KEY = "***********************************";


    // Result file name
    const string ResultFileName = @".\barcode.png";
    // Barcode type. See valid barcode types in the documentation https://developer.pdf.co
    const string BarcodeType = "Code128";
    // Barcode value
    const string BarcodeValue = "qweasd123456";


    static void Main(string[] args)
    {
      // Create standard .NET web client instance
      WebClient webClient = new WebClient();

      // Set API Key
      webClient.Headers.Add("x-api-key", API_KEY);

      // Prepare requests params as JSON
            // See documentation: https://apidocs.pdf.co/#barcode-generator
            Dictionary<string, string> parameters = new Dictionary<string, string>();
            parameters.Add("name", Path.GetFileName(ResultFileName));
            parameters.Add("type", BarcodeType);
            parameters.Add("value", BarcodeValue);
            // Convert dictionary of params to JSON
            string jsonPayload = JsonConvert.SerializeObject(parameters);

      try
      {
                // URL of "Barcode Generator" endpoint
                string url = "https://api.pdf.co/v1/barcode/generate";

                // Execute POST request with JSON payload
                string response = webClient.UploadString(url, jsonPayload);

        // Parse JSON response
        JObject json = JObject.Parse(response);

        if (json["error"].ToObject<bool>() == false)
        {
          // Get URL of generated barcode image file
          string resultFileURI = json["url"].ToString();

          // Download generated image file
          webClient.DownloadFile(resultFileURI, ResultFileName);

          Console.WriteLine("Generated barcode saved to \"{0}\" file.", ResultFileName);
        }
        else
        {
          Console.WriteLine(json["message"].ToString());
        }
      }
      catch (WebException e)
      {
        Console.WriteLine(e.ToString());
      }
            finally
            {
                webClient.Dispose();
            }


      Console.WriteLine();
      Console.WriteLine("Press any key...");
      Console.ReadKey();
    }
  }
}

package com.company;

import com.google.gson.JsonObject;
import com.google.gson.JsonParser;
import okhttp3.*;

import java.io.*;
import java.net.*;
import java.nio.file.Path;
import java.nio.file.Paths;

public class Main
{
    // The authentication key (API Key).
    // Get your own by registering at https://app.pdf.co
    final static String API_KEY = "***********************************";

    // Result file name
    final static Path ResultFile = Paths.get(".\\barcode.png");
    // Barcode type. See valid barcode types in the documentation https://developer.pdf.co
    final static String BarcodeType = "Code128";
    // Barcode value
    final static String BarcodeValue = "qweasd123456";


    public static void main(String[] args) throws IOException
    {
        // Create HTTP client instance
        OkHttpClient webClient = new OkHttpClient();

        // Prepare URL for `Barcode Generator` API call
        String query = "https://api.pdf.co/v1/barcode/generate";

        // Make correctly escaped (encoded) URL
        URL url = null;
        try
        {
            url = new URI(null, query, null).toURL();
        }
        catch (URISyntaxException e)
        {
            e.printStackTrace();
        }

        // Create JSON payload
        String jsonPayload = String.format("{\"name\": \"%s\", \"type\": \"%s\", \"value\": \"%s\"}",
            ResultFile.getFileName(),
            BarcodeType,
            BarcodeValue);

        // Prepare request body
        RequestBody body = RequestBody.create(MediaType.parse("application/json"), jsonPayload);

        // Prepare request
        Request request = new Request.Builder()
            .url(url)
            .addHeader("x-api-key", API_KEY) // (!) Set API Key
            .addHeader("Content-Type", "application/json")
            .post(body)
            .build();

        // Execute request
        Response response = webClient.newCall(request).execute();

        if (response.code() == 200)
        {
            // Parse JSON response
            JsonObject json = new JsonParser().parse(response.body().string()).getAsJsonObject();

            boolean error = json.get("error").getAsBoolean();
            if (!error)
            {
                // Get URL of generated barcode image file
                String resultFileUrl = json.get("url").getAsString();

                // Download the image file
                downloadFile(webClient, resultFileUrl, ResultFile);

                System.out.printf("Generated barcode saved to \"%s\" file.", ResultFile.toString());
            }
            else
            {
                // Display service reported error
                System.out.println(json.get("message").getAsString());
            }
        }
        else
        {
            // Display request error
            System.out.println(response.code() + " " + response.message());
        }
    }

    public static void downloadFile(OkHttpClient webClient, String url, Path destinationFile) throws IOException
    {
        // Prepare request
        Request request = new Request.Builder()
                .url(url)
                .build();
        // Execute request
        Response response = webClient.newCall(request).execute();

        byte[] fileBytes = response.body().bytes();

        // Save downloaded bytes to file
        OutputStream output = new FileOutputStream(destinationFile.toFile());
        output.write(fileBytes);
        output.flush();
        output.close();

        response.close();
    }
}

<?php

  // Get submitted form data
  $apiKey = $_POST["apiKey"]; // The authentication key (API Key). Get your own by registering at https://app.pdf.co
  $barcodeType = $_POST["barcodeType"];
  $barcodeValue = $_POST["inputValue"];

  // Create URL
  $url = "https://api.pdf.co/v1/barcode/generate";

  // Prepare requests params
  $parameters = array();
  $parameters["value"] = $barcodeValue;
  $parameters["type"] = $barcodeType;

  // Create Json payload
  $data = json_encode($parameters);

  // Create request
  $curl = curl_init();
  curl_setopt($curl, CURLOPT_HTTPHEADER, array("x-api-key: " . $apiKey, "Content-type: application/json"));
  curl_setopt($curl, CURLOPT_URL, $url);
  curl_setopt($curl, CURLOPT_POST, true);
  curl_setopt($curl, CURLOPT_RETURNTRANSFER, 1);
  curl_setopt($curl, CURLOPT_POSTFIELDS, $data);

  // Execute request
  $result = curl_exec($curl);

  if (curl_errno($curl) == 0)
  {
      $status_code = curl_getinfo($curl, CURLINFO_HTTP_CODE);

      if ($status_code == 200)
      {
          $json = json_decode($result, true);

          if (!isset($json["error"]) || $json["error"] == false)
          {
              $resultFileUrl = $json["url"];

              // Display generated image
              echo "<div>## Result:<img src=" . $resultFileUrl . "></div>";
          }
          else
          {
              // Display service reported errors
              echo "<p>Error: " . $json["message"] . "</p>";
          }
      }
      else
      {
          // Display request error
          echo "<p>Status code: " . $status_code . "</p>";
          echo "<p>" . $result . "</p>";
      }
  }
  else
  {
      // Display CURL error
      echo "Error: " . curl_error($curl);
  }

  // Cleanup
  curl_close($curl);

?>