diff --git a/src/vector/rageshake.js b/src/vector/rageshake.js index f4fe4396d..7d1a93efc 100644 --- a/src/vector/rageshake.js +++ b/src/vector/rageshake.js @@ -99,6 +99,11 @@ class IndexedDBLogStore { this.id = "instance-" + Math.random() + Date.now(); this.index = 0; this.db = null; + // Promise is not null when a flush is IN PROGRESS + this.flushPromise = null; + // Promise is not null when flush() is called when one is already in + // progress. + this.flushAgainPromise = null; } /** @@ -148,35 +153,80 @@ class IndexedDBLogStore { } /** + * Flush logs to disk. + * + * There are guards to protect against race conditions in order to ensure + * that all previous flushes have completed before the most recent flush. + * Consider without guards: + * - A calls flush() periodically. + * - B calls flush() and wants to send logs immediately afterwards. + * - If B doesn't wait for A's flush to complete, B will be missing the + * contents of A's flush. + * To protect against this, we set 'flushPromise' when a flush is ongoing. + * Subsequent calls to flush() during this period return a new promise + * 'flushAgainPromise' which is chained off the current 'flushPromise'. + * Subsequent calls to flush() when the first flush hasn't completed will + * return the same 'flushAgainPromise' as we can guarantee that we WILL + * do a brand new flush at some point in the future. Once the first flush + * has completed, 'flushAgainPromise' becomes 'flushPromise' and can be + * chained again. + * + * This guarantees that we will always eventually do a flush when flush() is + * called. + * * @return {Promise} Resolved when the logs have been flushed. */ flush() { - if (!this.db) { - // not connected yet or user rejected access for us to r/w to the db - return Promise.reject(new Error("No connected database")); + if (this.flushPromise) { // a flush is ongoing + if (this.flushAgainPromise) { // a flush is queued up, return that. + return this.flushAgainPromise; + } + // queue up a new flush + this.flushAgainPromise = this.flushPromise.then(() => { + // the current flush has completed, so shuffle the promises + // around: + // flushAgainPromise => flushPromise and null flushAgainPromise. + // flushPromise has already nulled itself. + this.flushAgainPromise = null; + return this.flush(); + }); + return this.flushAgainPromise; } - const lines = this.logger.flush(); - if (lines.length === 0) { - return Promise.resolve(); - } - return new Promise((resolve, reject) => { + + this.flushPromise = new Promise((resolve, reject) => { + if (!this.db) { + // not connected yet or user rejected access for us to r/w to + // the db. + this.flushPromise = null; + reject(new Error("No connected database")); + return; + } + const lines = this.logger.flush(); + if (lines.length === 0) { + this.flushPromise = null; + resolve(); + return; + } let txn = this.db.transaction(["logs", "logslastmod"], "readwrite"); let objStore = txn.objectStore("logs"); objStore.add(this._generateLogEntry(lines)); let lastModStore = txn.objectStore("logslastmod"); lastModStore.put(this._generateLastModifiedTime()); txn.oncomplete = (event) => { + this.flushPromise = null; resolve(); }; txn.onerror = (event) => { console.error( "Failed to flush logs : ", event ); + this.flushPromise = null; reject( new Error("Failed to write logs: " + event.target.errorCode) ); } }); + return this.flushPromise; } /** @@ -368,17 +418,6 @@ module.exports = { return initPromise; }, - /** - * Force-flush the logs to storage. - * @return {Promise} Resolved when the logs have been flushed. - */ - flush: async function() { - if (!store) { - return; - } - await store.flush(); - }, - /** * Clean up old logs. * @return Promise Resolves if cleaned logs. @@ -422,17 +461,20 @@ module.exports = { // If in incognito mode, store is null, but we still want bug report // sending to work going off the in-memory console logs. + console.log("Sending bug report."); let logs = []; if (store) { + // flush most recent logs + await store.flush(); logs = await store.consume(); } - // and add the most recent console logs which won't be in the store yet. - const consoleLogs = logger.flush(); // remove logs from console - const currentId = store ? store.id : "-"; - logs.unshift({ - lines: consoleLogs, - id: currentId, - }); + else { + logs.push({ + lines: logger.flush(), + id: "-", + }); + } + await new Promise((resolve, reject) => { request({ method: "POST",