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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
"use strict";
var { Front } = require("resource://devtools/shared/protocol/Front.js");
/**
* Generates request methods as described by the given actor specification on
* the given front prototype. Returns the front prototype.
*/
var generateRequestMethods = function (actorSpec, frontProto) {
if (frontProto._actorSpec) {
throw new Error("frontProto called twice on the same front prototype!");
}
frontProto.typeName = actorSpec.typeName;
// Generate request methods.
const methods = actorSpec.methods;
methods.forEach(spec => {
const name = spec.name;
frontProto[name] = function (...args) {
// If the front is destroyed, the request will not be able to complete.
if (this.isDestroyed()) {
throw new Error(
`Can not send request '${name}' because front '${this.typeName}' is already destroyed.`
);
}
const startTime = Cu.now();
let packet;
try {
packet = spec.request.write(args, this);
} catch (ex) {
console.error("Error writing request: " + name);
throw ex;
}
if (spec.oneway) {
// Fire-and-forget oneway packets.
this.send(packet);
return undefined;
}
return this.request(packet).then(response => {
let ret;
if (!this.conn) {
throw new Error("Missing conn on " + this);
}
if (this.isDestroyed()) {
throw new Error(
`Can not interpret '${name}' response because front '${this.typeName}' is already destroyed.`
);
}
try {
ret = spec.response.read(response, this);
} catch (ex) {
console.error("Error reading response to: " + name + "\n" + ex);
throw ex;
}
ChromeUtils.addProfilerMarker(
"RDP Front",
startTime,
`${this.typeName}:${name}()`
);
return ret;
});
};
// Release methods should call the destroy function on return.
if (spec.release) {
const fn = frontProto[name];
frontProto[name] = function (...args) {
return fn.apply(this, args).then(result => {
this.destroy();
return result;
});
};
}
});
// Process event specifications
frontProto._clientSpec = {};
const actorEvents = actorSpec.events;
if (actorEvents) {
frontProto._clientSpec.events = new Map();
for (const [name, request] of actorEvents) {
frontProto._clientSpec.events.set(request.type, {
name,
request,
});
}
}
frontProto._actorSpec = actorSpec;
return frontProto;
};
/**
* Create a front class for the given actor specification and front prototype.
*
* @param object actorSpec
* The actor specification you're creating a front for.
* @param object proto
* The object prototype. Must have a 'typeName' property,
* should have method definitions, can have event definitions.
*/
var FrontClassWithSpec = function (actorSpec) {
class OneFront extends Front {}
generateRequestMethods(actorSpec, OneFront.prototype);
return OneFront;
};
exports.FrontClassWithSpec = FrontClassWithSpec;