repo_description: Minimal implementation of the Mimblewimble protocol.
repo_topics: cryptocurrency cryptography grin mimblewimble rust zero-knowledge-proofs
code: use crate::rest::*;
  use crate::router::ResponseFuture;
  use futures::future::ok;
  use hyper::body;
  use hyper::{Body, Request, Response, StatusCode};
  use serde::{Deserialize, Serialize};
  use std::collections::HashMap;
  use std::fmt::Debug;
  use std::io::Cursor;
  use url::form_urlencoded;
  
  /// Parse request body
  pub async fn parse_body<T>(req: Request<Body>) -> Result<T, Error>
  where
  	for<'de> T: Deserialize<'de> + Send + 'static,
  {
  	let raw = body::to_bytes(req.into_body())
  		.await
  		.map_err(|e| Error::RequestError(format!("Failed to read request: {}", e)))?;
  
  	let cursor = Cursor::new(raw);
  	serde_json::from_reader(cursor)
  		.map_err(|e| Error::RequestError(format!("Invalid request body: {}", e)))
  }
  
  /// Convert Result to ResponseFuture
  pub fn result_to_response<T>(res: Result<T, Error>) -> ResponseFuture
  where
  	T: Serialize,
  {
  	match res {
  		Ok(s) => json_response_pretty(&s),
  		Err(e) => match e {
  			Error::Argument(msg) => response(StatusCode::BAD_REQUEST, msg.clone()),
  			Error::RequestError(msg) => response(StatusCode::BAD_REQUEST, msg.clone()),
  			Error::NotFound => response(StatusCode::NOT_FOUND, ""),
  			Error::Internal(msg) => response(StatusCode::INTERNAL_SERVER_ERROR, msg.clone()),
  			Error::ResponseError(msg) => response(StatusCode::INTERNAL_SERVER_ERROR, msg.clone()),
  			// place holder
  			Error::Router { .. } => response(StatusCode::INTERNAL_SERVER_ERROR, ""),
  		},
  	}
  }
  
  /// Utility to serialize a struct into JSON and produce a sensible Response
  /// out of it.
  pub fn json_response<T>(s: &T) -> ResponseFuture
  where
  	T: Serialize,
  {
  	match serde_json::to_string(s) {
  		Ok(json) => response(StatusCode::OK, json),
  		Err(_) => response(StatusCode::INTERNAL_SERVER_ERROR, ""),
  	}
  }
  
  /// Pretty-printed version of json response as future
  pub fn json_response_pretty<T>(s: &T) -> ResponseFuture
  where
  	T: Serialize,
  {
  	match serde_json::to_string_pretty(s) {
  		Ok(json) => response(StatusCode::OK, json),
  		Err(e) => response(
  			StatusCode::INTERNAL_SERVER_ERROR,
  			format!("can't create json response: {}", e),
  		),
  	}
  }
  
  /// Text response as HTTP response
  pub fn just_response<T: Into<Body> + Debug>(status: StatusCode, text: T) -> Response<Body> {
  	let mut resp = Response::new(text.into());
  	*resp.status_mut() = status;
  	resp
  }
  
  /// Text response as future
  pub fn response<T: Into<Body> + Debug>(status: StatusCode, text: T) -> ResponseFuture {
  	Box::pin(ok(just_response(status, text)))
  }
  
  pub struct QueryParams {
  	params: HashMap<String, Vec<String>>,
  }
  
  impl QueryParams {
  	pub fn process_multival_param<F>(&self, name: &str, mut f: F)
  	where
  		F: FnMut(&str),
  	{
  		if let Some(ids) = self.params.get(name) {
  			for id in ids {
  				for id in id.split(',') {
  					f(id);
  				}
  			}
  		}
  	}
  
  	pub fn get(&self, name: &str) -> Option<&String> {
  		self.params.get(name).and_then(|v| v.first())
  	}
  }
  
  impl From<&str> for QueryParams {
  	fn from(query_string: &str) -> Self {
  		let params = form_urlencoded::parse(query_string.as_bytes())
  			.into_owned()
  			.fold(HashMap::new(), |mut hm, (k, v)| {
  				hm.entry(k).or_insert_with(|| vec![]).push(v);
  				hm
  			});
  		QueryParams { params }
  	}
  }
  
  impl From<Option<&str>> for QueryParams {
  	fn from(query_string: Option<&str>) -> Self {
  		match query_string {
  			Some(query_string) => Self::from(query_string),
  			None => QueryParams {
  				params: HashMap::new(),
  			},
  		}
  	}
  }
  
  impl From<Request<Body>> for QueryParams {
  	fn from(req: Request<Body>) -> Self {
  		Self::from(req.uri().query())
  	}
  }
  
  #[macro_export]
  macro_rules! right_path_element(
  	($req: expr) =>(
  		match $req.uri().path().trim_end_matches('/').rsplit('/').next() {
  			None => return response(StatusCode::BAD_REQUEST, "invalid url"),
  			Some(el) => el,
  		}
  	));
  
  #[macro_export]
  macro_rules! must_get_query(
  	($req: expr) =>(
  		match $req.uri().query() {
  			Some(q) => q,
  			None => return Err(Error::RequestError("no query string".to_owned())),
  		}
  	));
  
  #[macro_export]
  macro_rules! parse_param(
  	($param: expr, $name: expr, $default: expr) =>(
  	match $param.get($name) {
  		None => $default,
  		Some(val) =>  match val.parse() {
  			Ok(val) => val,
  			Err(_) => return Err(Error::RequestError(format!("invalid value of parameter {}", $name))),
  		}
  	}
  	));
  
  #[macro_export]
  macro_rules! parse_param_no_err(
  	($param: expr, $name: expr, $default: expr) =>(
  	match $param.get($name) {
  		None => $default,
  		Some(val) =>  match val.parse() {
  			Ok(val) => val,
  			Err(_) => $default,
  		}
  	}
  	));
  
  #[macro_export]
  macro_rules! w_fut(
  	($p: expr) =>(
  		match w($p) {
  			Ok(p) => p,
  			Err(_) => return response(StatusCode::INTERNAL_SERVER_ERROR, "weak reference upgrade failed" ),
  		}
  	));
  