HTTP

HTTP client and server functionality for Julia

Documentation	Build Status

Quick Start Guide

1. Install Julia from the offical Julia website: https://julialang.org/downloads/

2. Add and import the HTTP Package

   julia> import Pkg
   julia> Pkg.add("HTTP")
   julia> using HTTP

3. Set up and a server and client:

   • Start the server in one instance of Julia

   using HTTP
   
   function handle_request(req)
       return HTTP.Response(200, "Hello World!")
   end
   
   HTTP.serve(handle_request, "localhost", 8080)

   This server will listen on port 8080 and respond "Hello World" to any incoming requests!

   • Start the client in another instance of Julia

   using HTTP
   
   url = "http://localhost:8080"
   response = HTTP.get(url)
   println("Response Status: ", response.status)
   println("Response Body: ", String(response.body))

Installation

The package can be installed with Julia's package manager, either by using the Pkg REPL mode (press ] to enter):

pkg> add HTTP

or by using Pkg functions

julia> using Pkg; Pkg.add("HTTP")

Project Status

The package has matured and is used in many production systems. But as with all open-source software, please try it out and report your experience.

The package is tested against current Julia LTS (1.6), and current master on Linux, macOS, and Windows.

Contributing and Questions

Contributions are very welcome, as are feature requests and suggestions. Please open an issue if you encounter any problems or would just like to ask a question.

Client Examples

HTTP.request sends a HTTP Request Message and returns a Response Message.

r = HTTP.request("GET", "http://httpbin.org/ip")
println(r.status)
println(String(r.body))

HTTP.open sends a HTTP Request Message and opens an IO stream from which the Response can be read.

HTTP.open(:GET, "https://tinyurl.com/bach-cello-suite-1-ogg") do http
    open(`vlc -q --play-and-exit --intf dummy -`, "w") do vlc
        write(vlc, http)
    end
end

Server Examples

HTTP.Servers.listen:

The server will start listening on 127.0.0.1:8081 by default.

using HTTP

# start a blocking server
HTTP.listen() do http::HTTP.Stream
    @show http.message
    @show HTTP.header(http, "Content-Type")
    while !eof(http)
        println("body data: ", String(readavailable(http)))
    end
    HTTP.setstatus(http, 404)
    HTTP.setheader(http, "Foo-Header" => "bar")
    HTTP.startwrite(http)
    write(http, "response body")
    write(http, "more response body")
end

HTTP.Handlers.serve:

using HTTP

# HTTP.listen! and HTTP.serve! are the non-blocking versions of HTTP.listen/HTTP.serve
server = HTTP.serve!() do request::HTTP.Request
   @show request
   @show request.method
   @show HTTP.header(request, "Content-Type")
   @show request.body
   try
       return HTTP.Response("Hello")
   catch e
       return HTTP.Response(400, "Error: $e")
   end
end
# HTTP.serve! returns an `HTTP.Server` object that we can close manually
close(server)

WebSocket Examples

julia> using HTTP.WebSockets
julia> server = WebSockets.listen!("127.0.0.1", 8081) do ws
        for msg in ws
            send(ws, msg)
        end
    end

julia> WebSockets.open("ws://127.0.0.1:8081") do ws
           send(ws, "Hello")
           s = receive(ws)
           println(s)
       end;
Hello

julia> close(server)