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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
"use strict";
const {
createStringGrip,
const {
getActorIdForInternalSourceId,
class nsIConsoleListenerWatcher {
/**
* Start watching for all messages related to a given Target Actor.
* This will notify about existing messages, as well as those created in the future.
*
* @param TargetActor targetActor
* The target actor from which we should observe messages
* @param Object options
* Dictionary object with following attributes:
* - onAvailable: mandatory function
* This will be called for each resource.
*/
async watch(targetActor, { onAvailable }) {
if (!this.shouldHandleTarget(targetActor)) {
return;
}
let latestRetrievedCachedMessageTimestamp = -1;
// Create the consoleListener.
const listener = {
QueryInterface: ChromeUtils.generateQI(["nsIConsoleListener"]),
observe: message => {
if (
message.microSecondTimeStamp <= latestRetrievedCachedMessageTimestamp
) {
return;
}
if (!this.shouldHandleMessage(targetActor, message)) {
return;
}
onAvailable([this.buildResource(targetActor, message)]);
},
};
// Retrieve the cached messages and get the last cached message timestamp before
// registering the listener, so we can ignore messages we'd be notified about but that
// were already retrieved in the cache.
const cachedMessages = Services.console.getMessageArray() || [];
if (cachedMessages.length) {
latestRetrievedCachedMessageTimestamp =
cachedMessages.at(-1).microSecondTimeStamp;
}
Services.console.registerListener(listener);
this.listener = listener;
// Remove unwanted cache messages and send an array of resources.
const messages = [];
for (const message of cachedMessages) {
if (!this.shouldHandleMessage(targetActor, message, true)) {
continue;
}
messages.push(this.buildResource(targetActor, message));
}
onAvailable(messages);
}
/**
* Return false if the watcher shouldn't be created.
*
* @param {TargetActor} targetActor
* @return {Boolean}
*/
shouldHandleTarget() {
return true;
}
/**
* Return true if you want the passed message to be handled by the watcher. This should
* be implemented on the child class.
*
* @param {TargetActor} targetActor
* @param {nsIScriptError|nsIConsoleMessage} message
* @return {Boolean}
*/
shouldHandleMessage() {
throw new Error(
"'shouldHandleMessage' should be implemented in the class that extends nsIConsoleListenerWatcher"
);
}
/**
* Prepare the resource to be sent to the client. This should be implemented on the
* child class.
*
* @param _targetActor
* @param nsIScriptError|nsIConsoleMessage _message
* @return object
* The object you can send to the remote client.
*/
buildResource(_targetActor, _message) {
throw new Error(
"'buildResource' should be implemented in the class that extends nsIConsoleListenerWatcher"
);
}
/**
* Prepare a SavedFrame stack to be sent to the client.
*
* @param {TargetActor} targetActor
* @param {SavedFrame} errorStack
* Stack for an error we need to send to the client.
* @return object
* The object you can send to the remote client.
*/
prepareStackForRemote(targetActor, errorStack) {
// Convert stack objects to the JSON attributes expected by client code
// nuked, stack is going to be a dead wrapper.
if (!errorStack || (Cu && Cu.isDeadWrapper(errorStack))) {
return null;
}
const stack = [];
let s = errorStack;
while (s) {
stack.push({
filename: s.source,
sourceId: getActorIdForInternalSourceId(targetActor, s.sourceId),
lineNumber: s.line,
columnNumber: s.column,
functionName: s.functionDisplayName,
asyncCause: s.asyncCause ? s.asyncCause : undefined,
});
s = s.parent || s.asyncParent;
}
return stack;
}
/**
* Prepare error notes to be sent to the client.
*
* @param {TargetActor} targetActor
* @param {nsIArray<nsIScriptErrorNote>} errorNotes
* @return object
* The object you can send to the remote client.
*/
prepareNotesForRemote(targetActor, errorNotes) {
if (!errorNotes?.length) {
return null;
}
const notes = [];
for (let i = 0, len = errorNotes.length; i < len; i++) {
const note = errorNotes.queryElementAt(i, Ci.nsIScriptErrorNote);
notes.push({
messageBody: createStringGrip(targetActor, note.errorMessage),
frame: {
source: note.sourceName,
sourceId: getActorIdForInternalSourceId(targetActor, note.sourceId),
line: note.lineNumber,
column: note.columnNumber,
},
});
}
return notes;
}
isProcessTarget(targetActor) {
const { typeName } = targetActor;
return (
typeName === "parentProcessTarget" || typeName === "contentProcessTarget"
);
}
/**
* Stop watching for messages.
*/
destroy() {
if (this.listener) {
Services.console.unregisterListener(this.listener);
}
}
}
module.exports = nsIConsoleListenerWatcher;