Simple Http

Simple Http is a header only C++ wrapper for libcurl. The aim is to have a small wrapper that introduces type safety and ergonomics while maintaining a small footprint.

Quick Start

The following example demonstrates an HTTP GET request with JSON parsing provided by nlohmann::json. All calls will return an HttpResult, which holds an underlying type of std::variant<SimpleHttp::HttpFailure, SimpleHttp::HttpSuccess>. An exhaustive handling of this result type can be performed by calling the match method and providing functions to handle success and failure. The match function expects unification of the witness type.

#include <iostream>
#include "nlohmann/json.hpp"
#include "simple_http.hpp"

int main() {
  SimpleHttp::Client client;
  SimpleHttp::HttpUrl url{"https://jsonplaceholder.typicode.com/users"};
  client.get(url).template match<void>(
      [&url](const SimpleHttp::HttpFailure &failure){
        failure.template match<void>(
            [&url](const SimpleHttp::HttpConnectionFailure &connectionFailure) {
              std::cout << "Failed GET for: " << url.value() << ", " << connectionFailure.value() << std::endl;
            },
            [&url](const SimpleHttp::HttpResponse &semanticFailure) {
              std::cout << "Failed GET for: " << url.value() << ", " << semanticFailure << std::endl;
            }
        );
      },
      [](const SimpleHttp::HttpSuccess &success){
        auto parsed = nlohmann::json::parse(success.body().value());
        std::cout << parsed[0]["id"] << std::endl;
      }
  );
}

Installation

Simple Http is a header only library. You can simply download and place in your project, or embed it with your favorite package manager. Using Simple Http will introduce a dependency on cURL, so you will need to ensure you link to curl when compiling your program.

Embedding With CMake

The following example demonstrates how to embed Simple Http into your project using CMake's FetchContent (CMake 3.11 or later).

include(FetchContent)

FetchContent_Declare(simple_http
    GIT_REPOSITORY https://github.com/abedra/simple_http
    GIT_TAG master # it's better to pick specific sha or tag here
    CONFIGURE_COMMAND ""
    BUILD_COMMAND "")

FetchContent_GetProperties(simple_http)

if(NOT simple_http_POPULATED)
  FetchContent_Populate(simple_http)
endif()

add_library(simple_http INTERFACE)
target_include_directories(simple_http INTERFACE ${simple_http_SOURCE_DIR})

# You may have a different way of resolving cURL. This is only here to provide a complete example
find_package(CURL)
if (CURL_FOUND)
  include_directories(${CURL_INCLUDE_DIR})
else (CURL_FOUND)
  message(FATAL_ERROR "CURL not found")
endif (CURL_FOUND)

target_link_libraries(${PROJECT_NAME} PRIVATE simple_http curl)

Advanced Usage

The integration tests are a good source of examples for the features provided by Simple Http. It is recommended to read through the tests to get a better sense for how to consume this library.