// Copyright 2018 The Grin Developers // // Licensed under the Apache License, Version 2.0 (the "License"); // you may not use this file except in compliance with the License. // You may obtain a copy of the License at // // http://www.apache.org/licenses/LICENSE-2.0 // // Unless required by applicable law or agreed to in writing, software // distributed under the License is distributed on an "AS IS" BASIS, // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. // See the License for the specific language governing permissions and // limitations under the License. //! High level JSON/HTTP client API use failure::{Fail, ResultExt}; use http::uri::{InvalidUri, Uri}; use hyper::header::{ACCEPT, USER_AGENT}; use hyper::rt::{Future, Stream}; use hyper::{Body, Client, Request}; use serde::{Deserialize, Serialize}; use serde_json; use futures::future::{err, ok, Either}; use tokio_core::reactor::Core; use rest::{Error, ErrorKind}; /// Helper function to easily issue a HTTP GET request against a given URL that /// returns a JSON object. Handles request building, JSON deserialization and /// response code checking. pub fn get<'a, T>(url: &'a str) -> Result where for<'de> T: Deserialize<'de>, { let uri = url.parse::().map_err::(|e: InvalidUri| { e.context(ErrorKind::Argument(format!("Invalid url {}", url))) .into() })?; let req = Request::builder() .method("GET") .uri(uri) .header(USER_AGENT, "grin-client") .header(ACCEPT, "application/json") .body(Body::empty()) .map_err(|_e| ErrorKind::RequestError("Bad request".to_owned()))?; handle_request(req) } /// Helper function to easily issue a HTTP POST request with the provided JSON /// object as body on a given URL that returns a JSON object. Handles request /// building, JSON serialization and deserialization, and response code /// checking. pub fn post(url: &str, input: &IN) -> Result where IN: Serialize, for<'de> OUT: Deserialize<'de>, { let req = create_post_request(url, input)?; handle_request(req) } /// Helper function to easily issue a HTTP POST request with the provided JSON /// object as body on a given URL that returns nothing. Handles request /// building, JSON serialization, and response code /// checking. pub fn post_no_ret(url: &str, input: &IN) -> Result<(), Error> where IN: Serialize, { let req = create_post_request(url, input)?; send_request(req)?; Ok(()) } fn create_post_request(url: &str, input: &IN) -> Result, Error> where IN: Serialize, { let json = serde_json::to_string(input).context(ErrorKind::Internal( "Could not serialize data to JSON".to_owned(), ))?; let uri = url.parse::().map_err::(|e: InvalidUri| { e.context(ErrorKind::Argument(format!("Invalid url {}", url))) .into() })?; Request::builder() .method("POST") .uri(uri) .header(USER_AGENT, "grin-client") .header(ACCEPT, "application/json") .body(json.into()) .map_err::(|e| { e.context(ErrorKind::RequestError("Bad request".to_owned())) .into() }) } fn handle_request(req: Request) -> Result where for<'de> T: Deserialize<'de>, { let data = send_request(req)?; serde_json::from_str(&data).map_err(|e| { e.context(ErrorKind::ResponseError("Cannot parse response".to_owned())) .into() }) } fn send_request(req: Request) -> Result { let mut event_loop = Core::new().unwrap(); let client = Client::new(); let task = client .request(req) .map_err(|_e| ErrorKind::RequestError("Cannot make request".to_owned())) .and_then(|resp| { if !resp.status().is_success() { Either::A(err(ErrorKind::RequestError( "Wrong response code".to_owned(), ))) } else { Either::B( resp.into_body() .map_err(|_e| { ErrorKind::RequestError("Cannot read response body".to_owned()) }) .concat2() .and_then(|ch| ok(String::from_utf8_lossy(&ch.to_vec()).to_string())), ) } }); Ok(event_loop.run(task)?) }