The http Fortran package provides a simple and convenient way to make HTTP requests and retrieve responses. It aims to simplify the process of interacting with web services by providing a high-level API.

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http-client is Fortran library to make HTTP requests. It simplifies interacting with web services by providing a high-level and user-friendly interface.


  • HTTP request methods:
  • GET: Retrieve data from the server.
  • POST: Create new data the server.
  • PUT: Replace an existing resource on the server.
  • DELETE: Delete a resource from the server.
  • PATCH: Partially update a resource on the server.
  • HEAD: Get response headers without the response content.
  • Supported data types:
  • URL encoded fields
  • HTTP form data
  • File uploads
  • Response handling:
  • Retrieve response body (content).
  • Get the HTTP status code returned by the server.
  • Access response headers.
  • Setting custom request headers
  • Error handling with informative error messages
  • Setting request timeouts
  • Basic HTTP authentication


Before building the http-client library, ensure that you have the necessary dependencies installed. On Ubuntu, you need to install the curl development headers. Use the following command:

sudo apt install -y libcurl4-openssl-dev

To use http-client as a dependency in your fpm project, add the following to your the fpm.toml file of your package:

http = { git = "" }
stdlib = "*"

Example use

The following example demonstrates how to use http-client to make a simple GET request and process the response:

program simple_get
    use http, only : response_type, request
    implicit none
    type(response_type) :: response

    ! Send a GET request to retrieve JSON data
    response = request(url='')

    ! Check if the request was successful
    if (.not. response%ok) then
        print *, 'Error message:', response%err_msg
        ! Print the response details
        print *, 'Response Code    :', response%status_code
        print *, 'Response Length  :', response%content_length
        print *, 'Response Method  :', response%method
        print *, 'Response Content :', response%content
    end if

end program simple_get


 Response Code    :          200
 Response Length  :                    83
 Response Method  : GET
 Response Content : {
  "userId": 1,
  "id": 1,
  "title": "delectus aut autem",
  "completed": false

In this example, we make a GET request to the URL to retrieve JSON data. If the request is successful, we print the response code, content length, method, and content. If the request fails, we print the error message.

Getting Started Guides

To begin your journey with our package, dive into the comprehensive tutorial available here:

Projects using http-client

  • github-org-analyzer: An example mini-project to demonstrate the use of http-client by downloading and parsing data from the GitHub API.
  • fortran-xkcd: An fpm example project that displays the latest xkcd comic inside an X window. As a limitation, only images in PNG format are supported. The alt text will be printed to console.
  • foropenai: A Fortran library to access the OpenAI API.
  • fortelegram-bot: An Example of simple telegram bot
  • forcompile: A Fortran library to access the Compiler Explorer API.

If you're using http-client in your Fortran project and would like to be included on this list, we welcome you to contribute by creating a pull request (PR) and adding your project details.

Contributing to project

Thank you for your interest in http-client! Contributions from the community are esential for improving the package. This section provides a guide on how to get the code, build the library, and run examples and tests.

Get the code

To get started, follow these steps:

Clone the repository using Git:

git clone
cd http-client


Before building the library, ensure that you have the necessary dependencies installed. On Ubuntu, you need to install the curl development headers. Use the following command:

sudo apt install -y libcurl4-openssl-dev

Build the library

http-client uses fpm as the build system. Make sure you have fpm-0.8.x or later installed. To build the library, run the following command within the project directory:

fpm build

Run examples

http-client provides example programs that demonstrate its use. To run the examples, use the following command:

fpm run --example <example name>

Executing this command will execute the example programs, allowing you to see the package in action and understand how to utilize its features.

Run tests

http-client includes a test suite to ensure its functionality is working as expected. To run the tests, type:

fpm test

Running the tests will validate the behavior of the package and help identify any issues or regressions.

Generating API Documentation

Before generating API documentation, ensure that you have FORD installed on your system.

Once FORD is set up, execute the following command to build the API documentation:


Supported compilers

http-client is known to work with the following compilers:

  • GFortran 11 & 12 (tested in CI)
  • Intel OneAPI ifx v2023.1.0 and ifort classic v2021.9.0

Contributing guidelines

When contributing to the http Fortran package, please keep the following guidelines in mind:

  • Before making any substantial changes, it is recommended to open an issue to discuss the proposed changes and ensure they align with the project's goals.
  • Fork the repository and create a new branch for your contribution.
  • Ensure that your code adheres to the existing coding style and follows good software engineering practices.
  • Write clear and concise commit messages.
  • Make sure to test your changes and ensure they do not introduce regressions or break existing functionality.
  • Submit a pull request with your changes, providing a clear explanation of the problem you are solving and the approach you have taken.

We appreciate your contributions and look forward to your valuable input in improving http-client.

Happy coding!👋

Developer Info

Rajkumar Dongre

Just Love to build Things 🛠️