developer-roadmap/src/data/roadmaps/cpp/content/libraries/102-poco.md

Poco

Poco (also known as POCO C++ Libraries) is a collection of open-source class libraries, which simplifies the creation of network-centric, portable, and maintainable software in C++.

Overview

Poco library provides functionality for various areas, such as:

• Networking: HTTP, FTP, SMTP, POP3, and other internet protocols
• File handling: FileSystem, Path, File, and Directory classes
• XML processing: XML parsing and DOM manipulation
• Logging: Loggers, levels, channels, patterns, etc.
• Data manipulation: Stream, ByteBuffer, Buffer, etc.
• Multithreading and synchronization: Threads, Mutex, Event, and Condition

Code Example

Here's an example demonstrating an HTTP client using the Poco library:

#include <Poco/Net/HTTPClientSession.h>
#include <Poco/Net/HTTPRequest.h>
#include <Poco/Net/HTTPResponse.h>
#include <Poco/Net/HTTPMessage.h>
#include <Poco/StreamCopier.h>
#include <iostream>
#include <string>

using namespace Poco::Net;
using namespace Poco;
using namespace std;

int main()
{
  try
  {
    // Prepare the request
    URI uri("http://example.com");
    HTTPClientSession session(uri.getHost(), uri.getPort());

    HTTPRequest request(HTTPRequest::HTTP_GET, uri.getPath(), HTTPMessage::HTTP_1_1);
    request.setContentType("application/json");

    session.sendRequest(request);

    // Process the response
    HTTPResponse response;
    istream& responseStream = session.receiveResponse(response);
    if (response.getStatus() == HTTPResponse::HTTP_OK)
    {
      // Successful
      StreamCopier::copyToString(responseStream, responseBody);
      cout << "Response: " << responseBody << endl;
    }
    else
    {
      // Error
      cout << "Error: " << response.getStatus() << " " << response.getReason() << endl;
    }
  }
  catch(const Exception& e)
  {
    cerr << "Error: " << e.displayText() << endl;
    return -1;
  }

  return 0;
}

In the above example, Poco is used to send an HTTP GET request and process the response. It manages tasks like connecting to the server, handling exceptions, and managing HTTP headers.

• Official Docs for Poco Library