1 //! Simple REST client implementation which implements [`BlockSource`] against a Bitcoin Core REST
4 use crate::{BlockData, BlockHeaderData, BlockSource, AsyncBlockSourceResult};
5 use crate::http::{BinaryResponse, HttpEndpoint, HttpClient, JsonResponse};
6 use crate::gossip::UtxoSource;
7 use crate::convert::GetUtxosResponse;
10 use bitcoin::hash_types::BlockHash;
12 use std::convert::TryFrom;
13 use std::convert::TryInto;
16 /// A simple REST client for requesting resources using HTTP `GET`.
17 pub struct RestClient {
18 endpoint: HttpEndpoint,
19 client: Mutex<Option<HttpClient>>,
23 /// Creates a new REST client connected to the given endpoint.
25 /// The endpoint should contain the REST path component (e.g., http://127.0.0.1:8332/rest).
26 pub fn new(endpoint: HttpEndpoint) -> std::io::Result<Self> {
27 Ok(Self { endpoint, client: Mutex::new(None) })
30 /// Requests a resource encoded in `F` format and interpreted as type `T`.
31 pub async fn request_resource<F, T>(&self, resource_path: &str) -> std::io::Result<T>
32 where F: TryFrom<Vec<u8>, Error = std::io::Error> + TryInto<T, Error = std::io::Error> {
33 let host = format!("{}:{}", self.endpoint.host(), self.endpoint.port());
34 let uri = format!("{}/{}", self.endpoint.path().trim_end_matches("/"), resource_path);
35 let mut client = if let Some(client) = self.client.lock().unwrap().take() { client }
36 else { HttpClient::connect(&self.endpoint)? };
37 let res = client.get::<F>(&uri, &host).await?.try_into();
38 *self.client.lock().unwrap() = Some(client);
43 impl BlockSource for RestClient {
44 fn get_header<'a>(&'a self, header_hash: &'a BlockHash, _height: Option<u32>) -> AsyncBlockSourceResult<'a, BlockHeaderData> {
46 let resource_path = format!("headers/1/{}.json", header_hash.to_string());
47 Ok(self.request_resource::<JsonResponse, _>(&resource_path).await?)
51 fn get_block<'a>(&'a self, header_hash: &'a BlockHash) -> AsyncBlockSourceResult<'a, BlockData> {
53 let resource_path = format!("block/{}.bin", header_hash.to_string());
54 Ok(BlockData::FullBlock(self.request_resource::<BinaryResponse, _>(&resource_path).await?))
58 fn get_best_block<'a>(&'a self) -> AsyncBlockSourceResult<'a, (BlockHash, Option<u32>)> {
60 Ok(self.request_resource::<JsonResponse, _>("chaininfo.json").await?)
65 impl UtxoSource for RestClient {
66 fn get_block_hash_by_height<'a>(&'a self, block_height: u32) -> AsyncBlockSourceResult<'a, BlockHash> {
68 let resource_path = format!("blockhashbyheight/{}.bin", block_height);
69 Ok(self.request_resource::<BinaryResponse, _>(&resource_path).await?)
73 fn is_output_unspent<'a>(&'a self, outpoint: OutPoint) -> AsyncBlockSourceResult<'a, bool> {
75 let resource_path = format!("getutxos/{}-{}.json", outpoint.txid.to_string(), outpoint.vout);
77 self.request_resource::<JsonResponse, GetUtxosResponse>(&resource_path).await?;
78 Ok(utxo_result.hit_bitmap_nonempty)
86 use crate::http::BinaryResponse;
87 use crate::http::client_tests::{HttpServer, MessageBody};
88 use bitcoin::hashes::Hash;
90 /// Parses binary data as a string-encoded `u32`.
91 impl TryInto<u32> for BinaryResponse {
92 type Error = std::io::Error;
94 fn try_into(self) -> std::io::Result<u32> {
95 match std::str::from_utf8(&self.0) {
96 Err(e) => Err(std::io::Error::new(std::io::ErrorKind::InvalidData, e)),
97 Ok(s) => match u32::from_str_radix(s, 10) {
98 Err(e) => Err(std::io::Error::new(std::io::ErrorKind::InvalidData, e)),
106 async fn request_unknown_resource() {
107 let server = HttpServer::responding_with_not_found();
108 let client = RestClient::new(server.endpoint()).unwrap();
110 match client.request_resource::<BinaryResponse, u32>("/").await {
111 Err(e) => assert_eq!(e.kind(), std::io::ErrorKind::Other),
112 Ok(_) => panic!("Expected error"),
117 async fn request_malformed_resource() {
118 let server = HttpServer::responding_with_ok(MessageBody::Content("foo"));
119 let client = RestClient::new(server.endpoint()).unwrap();
121 match client.request_resource::<BinaryResponse, u32>("/").await {
122 Err(e) => assert_eq!(e.kind(), std::io::ErrorKind::InvalidData),
123 Ok(_) => panic!("Expected error"),
128 async fn request_valid_resource() {
129 let server = HttpServer::responding_with_ok(MessageBody::Content(42));
130 let client = RestClient::new(server.endpoint()).unwrap();
132 match client.request_resource::<BinaryResponse, u32>("/").await {
133 Err(e) => panic!("Unexpected error: {:?}", e),
134 Ok(n) => assert_eq!(n, 42),
139 async fn parses_negative_getutxos() {
140 let server = HttpServer::responding_with_ok(MessageBody::Content(
141 // A real response contains a few more fields, but we actually only look at the
142 // "bitmap" field, so this should suffice for testing
143 "{\"chainHeight\": 1, \"bitmap\":\"0\",\"utxos\":[]}"
145 let client = RestClient::new(server.endpoint()).unwrap();
147 let outpoint = OutPoint::new(bitcoin::Txid::from_byte_array([0; 32]), 0);
148 let unspent_output = client.is_output_unspent(outpoint).await.unwrap();
149 assert_eq!(unspent_output, false);
153 async fn parses_positive_getutxos() {
154 let server = HttpServer::responding_with_ok(MessageBody::Content(
155 // A real response contains lots more data, but we actually only look at the "bitmap"
156 // field, so this should suffice for testing
157 "{\"chainHeight\": 1, \"bitmap\":\"1\",\"utxos\":[]}"
159 let client = RestClient::new(server.endpoint()).unwrap();
161 let outpoint = OutPoint::new(bitcoin::Txid::from_byte_array([0; 32]), 0);
162 let unspent_output = client.is_output_unspent(outpoint).await.unwrap();
163 assert_eq!(unspent_output, true);