--- /dev/null
+use crate::http::{HttpClient, HttpEndpoint, JsonResponse};
+
+use serde_json;
+
+use std::convert::TryFrom;
+use std::convert::TryInto;
+use std::sync::atomic::{AtomicUsize, Ordering};
+
+/// A simple RPC client for calling methods using HTTP `POST`.
+pub struct RpcClient {
+ basic_auth: String,
+ endpoint: HttpEndpoint,
+ client: HttpClient,
+ id: AtomicUsize,
+}
+
+impl RpcClient {
+ /// Creates a new RPC client connected to the given endpoint with the provided credentials. The
+ /// credentials should be a base64 encoding of a user name and password joined by a colon, as is
+ /// required for HTTP basic access authentication.
+ pub fn new(credentials: &str, endpoint: HttpEndpoint) -> std::io::Result<Self> {
+ let client = HttpClient::connect(&endpoint)?;
+ Ok(Self {
+ basic_auth: "Basic ".to_string() + credentials,
+ endpoint,
+ client,
+ id: AtomicUsize::new(0),
+ })
+ }
+
+ /// Calls a method with the response encoded in JSON format and interpreted as type `T`.
+ async fn call_method<T>(&mut self, method: &str, params: &[serde_json::Value]) -> std::io::Result<T>
+ where JsonResponse: TryFrom<Vec<u8>, Error = std::io::Error> + TryInto<T, Error = std::io::Error> {
+ let host = format!("{}:{}", self.endpoint.host(), self.endpoint.port());
+ let uri = self.endpoint.path();
+ let content = serde_json::json!({
+ "method": method,
+ "params": params,
+ "id": &self.id.fetch_add(1, Ordering::AcqRel).to_string()
+ });
+
+ let mut response = self.client.post::<JsonResponse>(&uri, &host, &self.basic_auth, content)
+ .await?.0;
+ if !response.is_object() {
+ return Err(std::io::Error::new(std::io::ErrorKind::InvalidData, "expected JSON object"));
+ }
+
+ let error = &response["error"];
+ if !error.is_null() {
+ // TODO: Examine error code for a more precise std::io::ErrorKind.
+ let message = error["message"].as_str().unwrap_or("unknown error");
+ return Err(std::io::Error::new(std::io::ErrorKind::Other, message));
+ }
+
+ let result = &mut response["result"];
+ if result.is_null() {
+ return Err(std::io::Error::new(std::io::ErrorKind::InvalidData, "expected JSON result"));
+ }
+
+ JsonResponse(result.take()).try_into()
+ }
+}
+
+#[cfg(test)]
+mod tests {
+ use super::*;
+ use crate::http::client_tests::{HttpServer, MessageBody};
+
+ /// Credentials encoded in base64.
+ const CREDENTIALS: &'static str = "dXNlcjpwYXNzd29yZA==";
+
+ /// Converts a JSON value into `u64`.
+ impl TryInto<u64> for JsonResponse {
+ type Error = std::io::Error;
+
+ fn try_into(self) -> std::io::Result<u64> {
+ match self.0.as_u64() {
+ None => Err(std::io::Error::new(std::io::ErrorKind::InvalidData, "not a number")),
+ Some(n) => Ok(n),
+ }
+ }
+ }
+
+ #[tokio::test]
+ async fn call_method_returning_unknown_response() {
+ let server = HttpServer::responding_with_not_found();
+ let mut client = RpcClient::new(CREDENTIALS, server.endpoint()).unwrap();
+
+ match client.call_method::<u64>("getblockcount", &[]).await {
+ Err(e) => assert_eq!(e.kind(), std::io::ErrorKind::NotFound),
+ Ok(_) => panic!("Expected error"),
+ }
+ }
+
+ #[tokio::test]
+ async fn call_method_returning_malfomred_response() {
+ let response = serde_json::json!("foo");
+ let server = HttpServer::responding_with_ok(MessageBody::Content(response));
+ let mut client = RpcClient::new(CREDENTIALS, server.endpoint()).unwrap();
+
+ match client.call_method::<u64>("getblockcount", &[]).await {
+ Err(e) => {
+ assert_eq!(e.kind(), std::io::ErrorKind::InvalidData);
+ assert_eq!(e.get_ref().unwrap().to_string(), "expected JSON object");
+ },
+ Ok(_) => panic!("Expected error"),
+ }
+ }
+
+ #[tokio::test]
+ async fn call_method_returning_error() {
+ let response = serde_json::json!({
+ "error": { "code": -8, "message": "invalid parameter" },
+ });
+ let server = HttpServer::responding_with_ok(MessageBody::Content(response));
+ let mut client = RpcClient::new(CREDENTIALS, server.endpoint()).unwrap();
+
+ let invalid_block_hash = serde_json::json!("foo");
+ match client.call_method::<u64>("getblock", &[invalid_block_hash]).await {
+ Err(e) => {
+ assert_eq!(e.kind(), std::io::ErrorKind::Other);
+ assert_eq!(e.get_ref().unwrap().to_string(), "invalid parameter");
+ },
+ Ok(_) => panic!("Expected error"),
+ }
+ }
+
+ #[tokio::test]
+ async fn call_method_returning_missing_result() {
+ let response = serde_json::json!({ "result": null });
+ let server = HttpServer::responding_with_ok(MessageBody::Content(response));
+ let mut client = RpcClient::new(CREDENTIALS, server.endpoint()).unwrap();
+
+ match client.call_method::<u64>("getblockcount", &[]).await {
+ Err(e) => {
+ assert_eq!(e.kind(), std::io::ErrorKind::InvalidData);
+ assert_eq!(e.get_ref().unwrap().to_string(), "expected JSON result");
+ },
+ Ok(_) => panic!("Expected error"),
+ }
+ }
+
+ #[tokio::test]
+ async fn call_method_returning_malformed_result() {
+ let response = serde_json::json!({ "result": "foo" });
+ let server = HttpServer::responding_with_ok(MessageBody::Content(response));
+ let mut client = RpcClient::new(CREDENTIALS, server.endpoint()).unwrap();
+
+ match client.call_method::<u64>("getblockcount", &[]).await {
+ Err(e) => {
+ assert_eq!(e.kind(), std::io::ErrorKind::InvalidData);
+ assert_eq!(e.get_ref().unwrap().to_string(), "not a number");
+ },
+ Ok(_) => panic!("Expected error"),
+ }
+ }
+
+ #[tokio::test]
+ async fn call_method_returning_valid_result() {
+ let response = serde_json::json!({ "result": 654470 });
+ let server = HttpServer::responding_with_ok(MessageBody::Content(response));
+ let mut client = RpcClient::new(CREDENTIALS, server.endpoint()).unwrap();
+
+ match client.call_method::<u64>("getblockcount", &[]).await {
+ Err(e) => panic!("Unexpected error: {:?}", e),
+ Ok(count) => assert_eq!(count, 654470),
+ }
+ }
+}
projects / rust-lightning / blobdiff