Newer
Older
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
// Copyright 2019 Parity Technologies (UK) Ltd.
// This file is part of Substrate.
// Substrate is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// Substrate is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with Substrate. If not, see <http://www.gnu.org/licenses/>.
use crate::ChainSpec;
use futures01::{prelude::*, sync::oneshot, sync::mpsc};
use libp2p::wasm_ext;
use log::{debug, info};
use std::sync::Arc;
use substrate_service::{AbstractService, RpcSession, Roles as ServiceRoles, Configuration, config::DatabaseConfig};
use wasm_bindgen::prelude::*;
/// Starts the client.
///
/// You must pass a libp2p transport that supports .
#[wasm_bindgen]
pub fn start_client(wasm_ext: wasm_ext::ffi::Transport) -> Result<Client, JsValue> {
start_inner(wasm_ext)
.map_err(|err| JsValue::from_str(&err.to_string()))
}
fn start_inner(wasm_ext: wasm_ext::ffi::Transport) -> Result<Client, Box<dyn std::error::Error>> {
console_error_panic_hook::set_once();
console_log::init_with_level(log::Level::Info);
// Build the configuration to pass to the service.
let config = {
let wasm_ext = wasm_ext::ExtTransport::new(wasm_ext);
let chain_spec = ChainSpec::FlamingFir.load().map_err(|e| format!("{:?}", e))?;
let mut config = Configuration::<(), _, _>::default_with_spec_and_base_path(chain_spec, None);
config.network.transport = network::config::TransportConfig::Normal {
wasm_external_transport: Some(wasm_ext.clone()),
allow_private_ipv4: true,
enable_mdns: false,
};
config.telemetry_external_transport = Some(wasm_ext);
config.roles = ServiceRoles::LIGHT;
config.name = "Browser node".to_string();
config.database = {
let db = Arc::new(kvdb_memorydb::create(10));
DatabaseConfig::Custom(db)
};
config
};
info!("Substrate browser node");
info!(" version {}", config.full_version());
info!(" by Parity Technologies, 2017-2019");
info!("Chain specification: {}", config.chain_spec.name());
info!("Node name: {}", config.name);
info!("Roles: {:?}", config.roles);
// Create the service. This is the most heavy initialization step.
let mut service = crate::service::new_light(config).map_err(|e| format!("{:?}", e))?;
// We now dispatch a background task responsible for processing the service.
//
// The main action performed by the code below consists in polling the service with
// `service.poll()`.
// The rest consists in handling RPC requests.
let (rpc_send_tx, mut rpc_send_rx) = mpsc::unbounded::<RpcMessage>();
wasm_bindgen_futures::spawn_local(futures01::future::poll_fn(move || {
loop {
match rpc_send_rx.poll() {
Ok(Async::Ready(Some(message))) => {
let fut = service.rpc_query(&message.session, &message.rpc_json);
let _ = message.send_back.send(Box::new(fut));
},
Ok(Async::NotReady) => break,
Err(_) | Ok(Async::Ready(None)) => return Ok(Async::Ready(())),
}
}
loop {
match service.poll().map_err(|_| ())? {
Async::Ready(()) => return Ok(Async::Ready(())),
Async::NotReady => break
}
}
Ok(Async::NotReady)
}));
Ok(Client {
rpc_send_tx,
})
}
/// A running client.
#[wasm_bindgen]
pub struct Client {
rpc_send_tx: mpsc::UnboundedSender<RpcMessage>,
}
struct RpcMessage {
rpc_json: String,
session: RpcSession,
send_back: oneshot::Sender<Box<dyn Future<Item = Option<String>, Error = ()>>>,
}
#[wasm_bindgen]
impl Client {
/// Allows starting an RPC request. Returns a `Promise` containing the result of that request.
#[wasm_bindgen(js_name = "rpcSend")]
pub fn rpc_send(&mut self, rpc: &str) -> js_sys::Promise {
let rpc_session = RpcSession::new(mpsc::channel(1).0);
let (tx, rx) = oneshot::channel();
let _ = self.rpc_send_tx.unbounded_send(RpcMessage {
rpc_json: rpc.to_owned(),
session: rpc_session,
send_back: tx,
});
let fut = rx
.map_err(|_| ())
.and_then(|fut| fut)
.map(|s| JsValue::from_str(&s.unwrap_or(String::new())))
.map_err(|_| JsValue::NULL);
wasm_bindgen_futures::future_to_promise(fut)
}
/// Subscribes to an RPC pubsub endpoint.
#[wasm_bindgen(js_name = "rpcSubscribe")]
pub fn rpc_subscribe(&mut self, rpc: &str, callback: js_sys::Function) {
let (tx, rx) = mpsc::channel(4);
let rpc_session = RpcSession::new(tx);
let (fut_tx, fut_rx) = oneshot::channel();
let _ = self.rpc_send_tx.unbounded_send(RpcMessage {
rpc_json: rpc.to_owned(),
session: rpc_session.clone(),
send_back: fut_tx,
});
let fut_rx = fut_rx
.map_err(|_| ())
.and_then(|fut| fut);
wasm_bindgen_futures::spawn_local(fut_rx.then(|_| Ok(())));
wasm_bindgen_futures::spawn_local(rx.for_each(move |s| {
match callback.call1(&callback, &JsValue::from_str(&s)) {
Ok(_) => Ok(()),
Err(_) => Err(()),
}
}).then(move |v| {
// We need to keep `rpc_session` alive.
debug!("RPC subscription has ended");
drop(rpc_session);
v
}));
}
}