tsurezure

this is a simple web server framework written in ruby. mainly made as a way for me to quickly put together rest apis in my favorite language.

it can be used in a very similar manner to the javascript framework express.

just run gem install tsurezure and you'll have whatever the latest version is that I've put up.

requires:

• ruby
• nodejs + nodemon (only for hot reloading server in development mode, not necessarily required)

after cloning this repo, from the root project directory, just run rake start to start in production mode, or rake dev to run in development mode, which adds hot reloading with nodemon. gem dependencies will install automatically.

to build the gem: run gem build tsurezure.gemspec. then, install using gem install tsurezure-version-number. version-number is whatever version is installed based on the .gemspec file.

• rake install will install dependencies
• rake check_deps will install dependencies if not installed
• rake start will run the server in production mode
• rake dev will run the server in development mode
• rake dev_silent will run the server in development mode with no logs
• rake build will build a .gem file based on tsurezure.gemspec

as for how to use tsurezure, here's a simple script to get started:

require 'tsurezure'

# create an instance of tsurezure
server = Tsurezure.new 8888

# url: http://localhost:8888

# create an endpoint
server.register 'get', '/user/:id', lambda { |req|
  url_vars = req[:vars] # { "id" => "1" }
  params = req[:params] # {}

  # create a respsonse for the endpoint
  {
    status: 200,
    message: {
      message: "hello user ##{url_vars['id']}!"
    }.to_json
  }
}, content_type: 'application/json' # options hash

# throw in some middleware
server.add_middleware '/user/:id', lambda { |req|
  url_vars = req[:vars]

  # show a different response based on the request itself.
  # if you return from middleware, the return value will
  # be sent as the final response.
  if req[:vars]['id'] == '1'
    return {
      status: 200, message: {
      message: "hey user #1! you're the first one here!"
    }.to_json
  }

  end
}, content_type: 'application/json'

#listen for connections
server.listen

after you run this file, open up your browser or whatever and go to http://localhost:8888/user/1. you should see a json response that looks like this:

{
    "message": "hey user #1! you're the first one here!"
}

by the way, any url parameters you pass in will be parsed as a hash inside req[:params]. so if you make a request like GET http://localhost:8888/user/1?hello=world, you'll be able to access those params inside your registration function. example:

server.register 'get', '/user/:id', lambda { |req|
  params = req[:params] # { 'hello' => 'world' }
}, content_type: 'application/json'

the listen method can be called with no arguments to just start the server. you can also pass in a lambda or proc that will run when the server has started. the only argument that will be passed to that proc is a hash called server_opts. it contains some information about the current configuration:

{
  port, # port that tsurezure is running on
  endpoints, # endpoints object containing the endpoints you've added
  middleware # middleware object containing the middleware you've added
}

simple example of usage:

server.listen lambda { |opts|
  puts "listening on port #{opts[:port]}!"
}

the registration function for creating endpoints is very simple:

register http_method, path, callback, options

http_method is the method to access the endpoint with. path is just the url.

path can be a path that contains variables (such as /user/:id). see the example above to see how it works.

callback is a lambda that contains the logic used to send a response. it will recieve one argument: the request that was sent to that endpoint. whatever is returned from the proc will be sent as the response from that endpoint.

options is a hash containing various options to somehow modify the response. valid options:

• content_type (default: text/plain) - determines the mime type of the response
• location - if a location header is required (301, etc), this is used to provide it.
• method - if an allow header is required (405), this is used to provide it.

for middleware, it's much the same:

add_middleware path, callback, options

path can be a path that contains variables. used in the same way as the path for endpoints.

callback is a lambda that you can use to intercept and pre-process responses. if you return from a callback in middleware, then that return value will be sent as the final response.

options for middleware are the same as the options for endpoints.

anything returned from a middleware will be interpreted as you trying to send a modified response. and of course, ruby will interpret the last reached statement in a method as an implicit return. to avoid this, if you want to have a middleware that doesn't necessarily send a response, just use a return at the end of your method to return nil.

• I'm wondering if I should change the implementation of the middleware functionality. currently, the middleware has no idea where the request it's processing is about to go. I'm thinking it may be a good idea to pass in the request's determined responder function which is determined before middleware is called (see tsurezure.rb:135-160). this will allow users to choose whether to call the final responder function. I don't know if this would be better or just different.

• make it so registered uris can only be accessed with the specified method, and everything else returns a 405 (maybe make this an option??)

• give the user an option to add middleware specifically for catching errors

disclaimer: I don't know ruby, and this is my first time using it to make something.

the name comes from yukueshirezutsurezure, one of my favorite bands. tsurezure is pronounced 'tsɯ-ɾe-dzɯ-ɾe.'