lovr-http

A Lua library for performing HTTP(S) requests. It's basically a teeny tiny version of lua-https included by default in LÖVR. Although lovr's in the name, the library is self-contained and it should work in any Lua program.

Example

http = require 'http'

status, data = http.request('https://zombo.com')

print('welcome')
print(status)
print(data)

API

The module has one function:

status, data, headers = http.request(url, [options])

Arguments

url is the URL to request. If it doesn't have a protocol, then http:// will be added.

options is optional, and is used for advanced request settings.

options.method is the HTTP method to use, also called the verb. GET is used by default if there's no data in the request, otherwise it defauls to POST. It will be converted to all-caps.

options.data is the data to send to the server, also called the body. It can be a few different types:

• When data is nil, no request body will be sent (and method will default to GET).
• When data is a string, the string will be used directly as the request body.
• When data is a table, then pairs in the table will be URL encoded and concatenated together to form an application/x-www-form-urlencoded body. For example, if data is { n = 10, k = 'v!' }, then the request body will be something like k=v%21&n=10. Keys can appear in any order. Table pairs will only be used if the key is a string and the value is a string or number.
• When data is a lightuserdata, the data pointed to by the lightuserdata will be used as the request body. Additionally, the datasize option should be an integer indicating how big the request body is, in bytes.

When options.data is set, the Content-Type request header will default to application/x-www-urlencoded unless it's set to something else.

options.headers is a table of request headers to send to the server. Pairs in the table will only be used if the key is a string and the value is a string or number.

Returns

If an error occurs, the function returns nil, errormessage.

Otherwise, 3 values are returned:

• status is an integer with the HTTP status code (200 is OK, 404 is Not Found, etc.).
• data is a string with the data sent by the server (HTML, JSON, binary, etc.).
• headers is a table of response headers.

Limitations

• multipart/form-data request bodies are not supported.
• Multi-line response headers are not parsed correctly on all platforms.
• There is no way to specify a request timeout, because not all platforms support it.
• There is currently no way to limit or restrict HTTP redirects. Redirects are generally followed.
• Adding credentials in the URL is not supported. Use the Authorization request header instead.
• There are differences in behavior between platforms. If you encounter any that are causing you problems, please open an issue.
• I don't even know what a proxy is but it's probably not going to work.

Compiling

The build system is CMake. The CMake script doesn't have any logic to link against Lua yet, so it will only build properly in LÖVR's plugins folder, where it will automatically use LÖVR's copy of Lua.

Implementation

lovr-http uses system-provided HTTP libraries:

• Windows uses wininet.
• Linux uses curl (must install e.g. libcurl4 package, but most systems have it).
• Android uses Java's HttpURLConnection via JNI.
• macOS uses NSURLSession.

The system's certificates are used for HTTPS.

License

MIT, see the LICENSE file for details.