WASM Electrum client (#946)

* Refactor Wasm WebSocket transport
* Move boilerplate code from connection states to the WsContext
* Fix the bug when the WsIncomingReceiver is opened, but the transport closes

* Configure the Electrum client to work in the browser
* Remove host_electrum_connect, host_electrum_is_connected, host_electrum_request, host_electrum_reply from defined-in-js.js
* Implement the rpc_clients::connect_loop wasm version
* Add wasm_ws::ws_transport that filters and maps the incoming WebSocketEvent
* Extend the wasm_build's index.html example

* Fix electrum_request timeout on WASM
* Add the 'FutureTimeoutExt' trait that works on WASM

* Fix electrum metrics

* Roll back prices.rs portfolio.rs

* Add WS and WSS protocols to the electrum request

* Add the handling of the WS closure reason
* Add the 'reason' field to 'WebSocketEvent::Closing', 'WebSocketEvent::Closed'
* Add the 'ClosureReason' variant

Cargo.toml

@@ -64,9 +64,6 @@ enum-primitive-derive = "0.1"
 fomat-macros = "0.2"
 futures01 = { version = "0.1", package = "futures" }
 futures-cpupool = "0.1"
-# NB: tokio-timer 2+ is targeted at "Tokio runtime" and heavy load (spawns several timer threads there),
-# whereas futures-timer works with any reactor and spawns one global timer thread (fits out load better).
-futures-timer = "0.1"
 futures = { version = "0.3.1", package = "futures", features = ["compat", "async-await"] }
 gstuff = { version = "0.6", features = ["nightly"] }
 hash256-std-hasher = "0.15.2"

js/defined-in-js.js

@@ -4,26 +4,6 @@
 export function host_ensure_dir_is_writable(ptr, len) {
 }
 
-// fn host_electrum_connect(ptr: *const c_char, len: i32) -> i32;
-export function host_electrum_connect(ptr, len) {
-    return 0;
-}
-
-// fn host_electrum_is_connected(ri: i32) -> i32;
-export function host_electrum_is_connected(ri) {
-    return 0;
-}
-
-// fn host_electrum_request(ri: i32, ptr: *const c_char, len: i32) -> i32;
-export function host_electrum_request(ri, ptr, len) {
-    return 0;
-}
-
-// fn host_electrum_reply(ri: i32, id: i32, rbuf: *mut c_char, rcap: i32) -> i32;
-export function host_electrum_reply(ri, id, rbuf, rcap) {
-    return 0;
-}
-
 // pub fn host_env(name: *const c_char, nameˡ: i32, rbuf: *mut c_char, rcap: i32) -> i32;
 export function host_env(name, name2, rbuf, rcap) {
     return 0;

mm2src/coins/Cargo.toml

@@ -29,7 +29,6 @@ fomat-macros = "0.2"
 futures01 = { version = "0.1", package = "futures" }
 # using select macro requires the crate to be named futures, compilation failed with futures03 name
 futures = { version = "0.3", package = "futures", features = ["compat", "async-await"] }
-futures-timer = "0.1"
 gstuff = { version = "0.6", features = ["nightly"] }
 hex = "0.3.2"
 http = "0.2"

mm2src/coins/qrc20.rs

@@ -23,14 +23,14 @@ use common::log::{error, warn};
 use common::mm_ctx::MmArc;
 use common::mm_error::prelude::*;
 use common::mm_number::MmNumber;
+use common::now_ms;
 use derive_more::Display;
 use ethabi::{Function, Token};
 use ethereum_types::{H160, U256};
 use futures::compat::Future01CompatExt;
 use futures::lock::MutexGuard as AsyncMutexGuard;
 use futures::{FutureExt, TryFutureExt};
 use futures01::Future;
-use gstuff::now_ms;
 use keys::bytes::Bytes as ScriptBytes;
 use keys::{Address as UtxoAddress, Address, Public};
 #[cfg(test)] use mocktopus::macros::*;

mm2src/coins/utxo.rs

@@ -80,6 +80,7 @@ use super::{BalanceError, BalanceFut, BalanceResult, CoinTransportMetrics, Coins
             WithdrawError, WithdrawFee, WithdrawRequest};
 
 #[cfg(test)] pub mod utxo_tests;
+#[cfg(target_arch = "wasm32")] pub mod utxo_wasm_tests;
 
 const SWAP_TX_SPEND_SIZE: u64 = 305;
 const KILO_BYTE: u64 = 1000;