ethers_providers/rpc/transports/
rw.rs

1//! A [JsonRpcClient] implementation that serves as a wrapper around two different [JsonRpcClient]
2//! and uses a dedicated client for read and the other for write operations
3
4use crate::{errors::ProviderError, JsonRpcClient};
5use async_trait::async_trait;
6use serde::{de::DeserializeOwned, Serialize};
7use thiserror::Error;
8
9/// A client containing two clients.
10///
11/// One is used for _read_ operations
12/// One is used for _write_ operations that consume gas `["eth_sendTransaction",
13/// "eth_sendRawTransaction"]`
14///
15/// **Note**: if the method is unknown this client falls back to the _read_ client
16// # Example
17#[derive(Debug, Clone)]
18pub struct RwClient<Read, Write> {
19    /// client used to read
20    r: Read,
21    /// client used to write
22    w: Write,
23}
24
25impl<Read, Write> RwClient<Read, Write> {
26    /// Creates a new client using two different clients
27    ///
28    /// # Example
29    ///
30    /// ```no_run
31    /// # use url::Url;
32    ///  async fn t(){
33    /// use ethers_providers::{Http, RwClient, Ws};
34    /// let http = Http::new(Url::parse("http://localhost:8545").unwrap());
35    /// let ws = Ws::connect("ws://localhost:8545").await.unwrap();
36    /// let rw = RwClient::new(http, ws);
37    /// # }
38    /// ```
39    pub fn new(r: Read, w: Write) -> RwClient<Read, Write> {
40        Self { r, w }
41    }
42
43    /// Returns the client used for read operations
44    pub fn read_client(&self) -> &Read {
45        &self.r
46    }
47
48    /// Returns the client used for write operations
49    pub fn write_client(&self) -> &Write {
50        &self.w
51    }
52
53    /// Returns a new `RwClient` with transposed clients
54    pub fn transpose(self) -> RwClient<Write, Read> {
55        let RwClient { r, w } = self;
56        RwClient::new(w, r)
57    }
58
59    /// Consumes the client and returns the underlying clients
60    pub fn split(self) -> (Read, Write) {
61        let RwClient { r, w } = self;
62        (r, w)
63    }
64}
65
66#[derive(Error, Debug)]
67/// Error thrown when using either read or write client
68pub enum RwClientError<Read, Write>
69where
70    Read: JsonRpcClient,
71    <Read as JsonRpcClient>::Error: crate::RpcError + Sync + Send + 'static,
72    Write: JsonRpcClient,
73    <Write as JsonRpcClient>::Error: crate::RpcError + Sync + Send + 'static,
74{
75    /// Thrown if the _read_ request failed
76    #[error(transparent)]
77    Read(Read::Error),
78    #[error(transparent)]
79    /// Thrown if the _write_ request failed
80    Write(Write::Error),
81}
82
83impl<Read, Write> crate::RpcError for RwClientError<Read, Write>
84where
85    Read: JsonRpcClient,
86    <Read as JsonRpcClient>::Error: crate::RpcError + Sync + Send + 'static,
87    Write: JsonRpcClient,
88    <Write as JsonRpcClient>::Error: crate::RpcError + Sync + Send + 'static,
89{
90    fn as_error_response(&self) -> Option<&super::JsonRpcError> {
91        match self {
92            RwClientError::Read(e) => e.as_error_response(),
93            RwClientError::Write(e) => e.as_error_response(),
94        }
95    }
96
97    fn as_serde_error(&self) -> Option<&serde_json::Error> {
98        match self {
99            RwClientError::Read(e) => e.as_serde_error(),
100            RwClientError::Write(e) => e.as_serde_error(),
101        }
102    }
103}
104
105impl<Read, Write> From<RwClientError<Read, Write>> for ProviderError
106where
107    Read: JsonRpcClient + 'static,
108    <Read as JsonRpcClient>::Error: Sync + Send + 'static,
109    Write: JsonRpcClient + 'static,
110    <Write as JsonRpcClient>::Error: Sync + Send + 'static,
111{
112    fn from(src: RwClientError<Read, Write>) -> Self {
113        ProviderError::JsonRpcClientError(Box::new(src))
114    }
115}
116
117#[cfg_attr(target_arch = "wasm32", async_trait(?Send))]
118#[cfg_attr(not(target_arch = "wasm32"), async_trait)]
119impl<Read, Write> JsonRpcClient for RwClient<Read, Write>
120where
121    Read: JsonRpcClient + 'static,
122    <Read as JsonRpcClient>::Error: Sync + Send + 'static,
123    Write: JsonRpcClient + 'static,
124    <Write as JsonRpcClient>::Error: Sync + Send + 'static,
125{
126    type Error = RwClientError<Read, Write>;
127
128    /// Sends a POST request with the provided method and the params serialized as JSON
129    /// over HTTP
130    async fn request<T, R>(&self, method: &str, params: T) -> Result<R, Self::Error>
131    where
132        T: std::fmt::Debug + Serialize + Send + Sync,
133        R: DeserializeOwned + Send,
134    {
135        match method {
136            "eth_sendTransaction" | "eth_sendRawTransaction" => {
137                self.w.request(method, params).await.map_err(RwClientError::Write)
138            }
139            _ => self.r.request(method, params).await.map_err(RwClientError::Read),
140        }
141    }
142}
ethers_providers/rpc/transports/rw.rs

ethers_providers/rpc/transports/
rw.rs
