Utopia is an extensible HTTP server framework for Luvit.io which is using "plugins" known as middlewares and is highly inspired by Connect.js.
lit install voronianski/utopia
local Utopia = require('utopia')
local app = Utopia:new()
-- respond to all requests
app:use(function (req, res)
res:finish('Hello from Utopia!')
end)
app:listen(8080)
The main component is an "app". This will store all the middleware added.
local app = Utopia:new()
The core of Utopia is "using" middleware. Middleware are added as a "stack"
where incoming requests will execute each middleware one-by-one until a middleware does not call nxt()
within it (unlike Javascript next
is predefined function in Lua, so argument cannot be named like this).
app:use(function middleware1 (req, res, nxt)
-- middleware 1
nxt()
end)
app:use(function middleware2 (req, res, nxt)
-- middleware 2
nxt()
end)
The :use()
method also takes an optional path string that is matched against
the beginning of the incoming request URL. This allows for basic routing:
app:use('/foo', function fooMiddleware (req, res, nxt)
-- req.url starts with "/foo"
nxt()
end)
app:use('/bar', function barMiddleware (req, res, nxt)
-- req.url starts with "/bar"
nxt()
end)
There are special cases of "error-handling" middleware. There are middleware where the function takes exactly 4 arguments. Errors that occur in the middleware added before the error middleware will invoke this middleware when errors occur.
app:use(function onerror (err, req, res, nxt)
-- an error occurred!
end)
The last step is to actually use the Utopia app in a server. The .listen()
method is a convenience to start a HTTP server:
local server = app:listen(port)
- favicon
- logger
- request-query
- body-parser
- cookie-parser
- route
- cors
- json-response
- static
- directory
- method-override
- timeout
- response-time
- response-methods
lit install
luvit ./test
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( OO )__________
/ | \
/o o| MIT \
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(__|__|(__|__|
MIT Licensed
Copyright (c) 2014-2016 Dmitri Voronianski [email protected]
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the 'Software'), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED 'AS IS', WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.