Redo http transport

The existing implementation has accumulated a lot of crust from initial
async support and use of hyper. Now that is using reqwest we can do many
things simpler.

Removed things that were needed for hyper but are handled already by
reqwest:
- setting the proxy
- setting the auth header
- setting the content type header
- setting content length header

Other changes:
- Move from struct with Future impl to BoxFuture. We were already using
BoxFuture internally anyawy.
- Log request and response as debug strings. This makes sure no control
characters like newlines end up in the output.
- Use from_utf8_lossy for the response log so that we can still
partially log non utf8 responses.
- Fix not handling batch responses according to the jsonrpc
specification which does not guarantee the ordering of the list.
- Add more context to error logs.
- Allow giving a custom client to the transport. This is useful for
example to set a timeout.

Cargo.toml

@@ -32,7 +32,7 @@ pin-project = "1.0"
 ## HTTP
 base64 = { version = "0.13", optional = true }
 bytes = { version = "1.0", optional = true }
-reqwest = { version = "0.11", optional = true, default-features = false }
+reqwest = { version = "0.11", optional = true, default-features = false, features = ["json"] }
 headers = { version = "0.3", optional = true }
 ## WS
 # async-native-tls = { git = "https://github.com/async-email/async-native-tls.git", rev = "b5b5562d6cea77f913d4cbe448058c031833bf17", optional = true, default-features = false }

src/helpers.rs

@@ -6,6 +6,7 @@ use futures::{
     Future,
 };
 use pin_project::pin_project;
+use serde::de::DeserializeOwned;
 use std::{marker::PhantomData, pin::Pin};
 
 /// Takes any type which is deserializable from rpc::Value and such a value and
@@ -70,12 +71,19 @@ pub fn build_request(id: usize, method: &str, params: Vec<rpc::Value>) -> rpc::C
 /// Parse bytes slice into JSON-RPC response.
 /// It looks for arbitrary_precision feature as a temporary workaround for https://github.com/tomusdrw/rust-web3/issues/460.
 pub fn to_response_from_slice(response: &[u8]) -> error::Result<rpc::Response> {
+    arbitrary_precision_deserialize_workaround(response).map_err(|e| Error::InvalidResponse(format!("{:?}", e)))
+}
+
+/// Deserialize bytes into T.
+/// It looks for arbitrary_precision feature as a temporary workaround for https://github.com/tomusdrw/rust-web3/issues/460.
+pub fn arbitrary_precision_deserialize_workaround<T>(bytes: &[u8]) -> Result<T, serde_json::Error>
+where
+    T: DeserializeOwned,
+{
     if cfg!(feature = "arbitrary_precision") {
-        let val: serde_json::Value =
-            serde_json::from_slice(response).map_err(|e| Error::InvalidResponse(format!("{:?}", e)))?;
-        serde_json::from_value(val).map_err(|e| Error::InvalidResponse(format!("{:?}", e)))
+        serde_json::from_value(serde_json::from_slice(bytes)?)
     } else {
-        serde_json::from_slice(response).map_err(|e| Error::InvalidResponse(format!("{:?}", e)))
+        serde_json::from_slice(bytes)
     }
 }