@theia/core
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Theia is a cloud & desktop IDE framework implemented in TypeScript.
266 lines • 10.7 kB
JavaScript
;
// *****************************************************************************
// Copyright (C) 2017 TypeFox and others.
//
// This program and the accompanying materials are made available under the
// terms of the Eclipse Public License v. 2.0 which is available at
// http://www.eclipse.org/legal/epl-2.0.
//
// This Source Code may also be made available under the following Secondary
// Licenses when the conditions for such availability set forth in the Eclipse
// Public License v. 2.0 are satisfied: GNU General Public License, version 2
// with the GNU Classpath Exception which is available at
// https://www.gnu.org/software/classpath/license.html.
//
// SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
// *****************************************************************************
Object.defineProperty(exports, "__esModule", { value: true });
exports.JsonRpcProxyFactory = exports.JsonRpcConnectionHandler = void 0;
/* eslint-disable @typescript-eslint/no-explicit-any */
const rpc_message_encoder_1 = require("../message-rpc/rpc-message-encoder");
const application_error_1 = require("../application-error");
const event_1 = require("../event");
const rpc_protocol_1 = require("../message-rpc/rpc-protocol");
class JsonRpcConnectionHandler {
constructor(path, targetFactory, factoryConstructor = JsonRpcProxyFactory) {
this.path = path;
this.targetFactory = targetFactory;
this.factoryConstructor = factoryConstructor;
}
onConnection(connection) {
const factory = new this.factoryConstructor();
const proxy = factory.createProxy();
factory.target = this.targetFactory(proxy);
factory.listen(connection);
}
}
exports.JsonRpcConnectionHandler = JsonRpcConnectionHandler;
const defaultRPCConnectionFactory = (channel, requestHandler) => new rpc_protocol_1.RpcProtocol(channel, requestHandler);
/**
* Factory for JSON-RPC proxy objects.
*
* A JSON-RPC proxy exposes the programmatic interface of an object through
* JSON-RPC. This allows remote programs to call methods of this objects by
* sending JSON-RPC requests. This takes place over a bi-directional stream,
* where both ends can expose an object and both can call methods each other's
* exposed object.
*
* For example, assuming we have an object of the following type on one end:
*
* class Foo {
* bar(baz: number): number { return baz + 1 }
* }
*
* which we want to expose through a JSON-RPC interface. We would do:
*
* let target = new Foo()
* let factory = new JsonRpcProxyFactory<Foo>('/foo', target)
* factory.onConnection(connection)
*
* The party at the other end of the `connection`, in order to remotely call
* methods on this object would do:
*
* let factory = new JsonRpcProxyFactory<Foo>('/foo')
* factory.onConnection(connection)
* let proxy = factory.createProxy();
* let result = proxy.bar(42)
* // result is equal to 43
*
* One the wire, it would look like this:
*
* --> {"jsonrpc": "2.0", "id": 0, "method": "bar", "params": {"baz": 42}}
* <-- {"jsonrpc": "2.0", "id": 0, "result": 43}
*
* Note that in the code of the caller, we didn't pass a target object to
* JsonRpcProxyFactory, because we don't want/need to expose an object.
* If we had passed a target object, the other side could've called methods on
* it.
*
* @param <T> - The type of the object to expose to JSON-RPC.
*/
class JsonRpcProxyFactory {
/**
* Build a new JsonRpcProxyFactory.
*
* @param target - The object to expose to JSON-RPC methods calls. If this
* is omitted, the proxy won't be able to handle requests, only send them.
*/
constructor(target, rpcConnectionFactory = defaultRPCConnectionFactory) {
this.target = target;
this.rpcConnectionFactory = rpcConnectionFactory;
this.onDidOpenConnectionEmitter = new event_1.Emitter();
this.onDidCloseConnectionEmitter = new event_1.Emitter();
this.waitForConnection();
}
waitForConnection() {
this.connectionPromise = new Promise(resolve => this.connectionPromiseResolve = resolve);
this.connectionPromise.then(connection => {
connection.channel.onClose(() => {
this.onDidCloseConnectionEmitter.fire(undefined);
// Wait for connection in case the backend reconnects
this.waitForConnection();
});
this.onDidOpenConnectionEmitter.fire(undefined);
});
}
/**
* Connect a MessageConnection to the factory.
*
* This connection will be used to send/receive JSON-RPC requests and
* response.
*/
listen(channel) {
const connection = this.rpcConnectionFactory(channel, (meth, args) => this.onRequest(meth, ...args));
connection.onNotification(event => this.onNotification(event.method, ...event.args));
this.connectionPromiseResolve(connection);
}
/**
* Process an incoming JSON-RPC method call.
*
* onRequest is called when the JSON-RPC connection received a method call
* request. It calls the corresponding method on [[target]].
*
* The return value is a Promise object that is resolved with the return
* value of the method call, if it is successful. The promise is rejected
* if the called method does not exist or if it throws.
*
* @returns A promise of the method call completion.
*/
async onRequest(method, ...args) {
try {
if (this.target) {
return await this.target[method](...args);
}
else {
throw new Error(`no target was set to handle ${method}`);
}
}
catch (error) {
const e = this.serializeError(error);
if (e instanceof rpc_message_encoder_1.ResponseError) {
throw e;
}
const reason = e.message || '';
const stack = e.stack || '';
console.error(`Request ${method} failed with error: ${reason}`, stack);
throw e;
}
}
/**
* Process an incoming JSON-RPC notification.
*
* Same as [[onRequest]], but called on incoming notifications rather than
* methods calls.
*/
onNotification(method, ...args) {
if (this.target) {
this.target[method](...args);
}
}
/**
* Create a Proxy exposing the interface of an object of type T. This Proxy
* can be used to do JSON-RPC method calls on the remote target object as
* if it was local.
*
* If `T` implements `JsonRpcServer` then a client is used as a target object for a remote target object.
*/
createProxy() {
const result = new Proxy(this, this);
return result;
}
/**
* Get a callable object that executes a JSON-RPC method call.
*
* Getting a property on the Proxy object returns a callable that, when
* called, executes a JSON-RPC call. The name of the property defines the
* method to be called. The callable takes a variable number of arguments,
* which are passed in the JSON-RPC method call.
*
* For example, if you have a Proxy object:
*
* let fooProxyFactory = JsonRpcProxyFactory<Foo>('/foo')
* let fooProxy = fooProxyFactory.createProxy()
*
* accessing `fooProxy.bar` will return a callable that, when called,
* executes a JSON-RPC method call to method `bar`. Therefore, doing
* `fooProxy.bar()` will call the `bar` method on the remote Foo object.
*
* @param target - unused.
* @param p - The property accessed on the Proxy object.
* @param receiver - unused.
* @returns A callable that executes the JSON-RPC call.
*/
get(target, p, receiver) {
if (p === 'setClient') {
return (client) => {
this.target = client;
};
}
if (p === 'getClient') {
return () => this.target;
}
if (p === 'onDidOpenConnection') {
return this.onDidOpenConnectionEmitter.event;
}
if (p === 'onDidCloseConnection') {
return this.onDidCloseConnectionEmitter.event;
}
const isNotify = this.isNotification(p);
return (...args) => {
const method = p.toString();
const capturedError = new Error(`Request '${method}' failed`);
return this.connectionPromise.then(connection => new Promise((resolve, reject) => {
try {
if (isNotify) {
connection.sendNotification(method, args);
resolve(undefined);
}
else {
const resultPromise = connection.sendRequest(method, args);
resultPromise
.catch((err) => reject(this.deserializeError(capturedError, err)))
.then((result) => resolve(result));
}
}
catch (err) {
reject(err);
}
}));
};
}
/**
* Return whether the given property represents a notification.
*
* A property leads to a notification rather than a method call if its name
* begins with `notify` or `on`.
*
* @param p - The property being called on the proxy.
* @return Whether `p` represents a notification.
*/
isNotification(p) {
return p.toString().startsWith('notify') || p.toString().startsWith('on');
}
serializeError(e) {
if (application_error_1.ApplicationError.is(e)) {
return new rpc_message_encoder_1.ResponseError(e.code, '', Object.assign({ kind: 'application' }, e.toJson()));
}
return e;
}
deserializeError(capturedError, e) {
if (e instanceof rpc_message_encoder_1.ResponseError) {
const capturedStack = capturedError.stack || '';
if (e.data && e.data.kind === 'application') {
const { stack, data, message } = e.data;
return application_error_1.ApplicationError.fromJson(e.code, {
message: message || capturedError.message,
data,
stack: `${capturedStack}\nCaused by: ${stack}`
});
}
e.stack = capturedStack;
}
return e;
}
}
exports.JsonRpcProxyFactory = JsonRpcProxyFactory;
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