warp-dsl

DSL to write routes for warp, inspired by Akka HTTP.

At this moment, this implementation is just a proof of concept.

It works on Rust stable, using proc-macro-hack.

Getting Started

1. Add the following dependencies to your Cargo.toml:

   [dependencies]
   warp = "0.1"
   warp_dsl = "0.0.1"

2. Use #[macro_use] to declare both crates:

   #[macro_use] extern crate warp;
   #[macro_use] extern crate warp_dsl;

3. Write some routes:

   use warp::Filter;
   
   fn main() {
       let routes = router!(
           path("foo" / u64) |num| {
               get {
                   complete { format!("GET /foo/{}\n", num) }
               }
   
               post {
                   complete { format!("POST /foo/{}\n", num) }
               }
           }
       );
   
       warp::serve(routes).run(([0; 4], 3030));
   }

Then, type cargo run to start the HTTP server with these routes.

$ cargo run &

$ curl -X POST localhost:3030/foo/1 
POST /foo/1

Writing Routes

This section is just a draft. It needs to be expanded.

This crate uses the concept of directives from Akka HTTP.

Some common filters are recognized by the parser:

Directive	Expression
path(...)	path!(...)
index	warp::index()
get, post, put, …	HTTP methods
cookie("..")	::warp::filters::cookie::cookie
cookie(optional "..")	::warp::filters::cookie::optional

Any function can be used as a directive if:

• It returns a Filter.
• The expression is surrounded by parenthesis.

Nested directives are combined using Filter::and. Directives in the same level are combined using Filter::or.

The & operator can be used to combine nested directives. foo & bar { ... } is equivalent to foo { bar { ... } }.

HTTP methods are moved to the top of the filter, since in wrap 0.1 they can't be used with and().

The response is set using the complete directive.

Debugging

If you have problems writing the routes, it may help to verify the generated code. Set the WARPDSL_DEBUG to output, and the code for every call to router!() is printed to stderr.

With the code of the Getting Started section, you get the following output:

======== [DEBUG:OUTPUT] ========
(((::warp::get((path!("foo" / u64)).map(|num| {format ! ( "GET /foo/{}\n" , num )}))))
.or((::warp::post((path!("foo" / u64)).map(|num| {format ! ( "POST /foo/{}\n" , num )})))))
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