Query IndexedDB for all results with index=0

This commit is contained in:
Kegan Dougal 2017-01-19 12:02:19 +00:00
parent 811086ac8e
commit 89d514a532
1 changed files with 41 additions and 5 deletions

View File

@ -24,7 +24,7 @@ limitations under the License.
// generates a random string which serves as the "ID" for that tab/session. These IDs are stored along with the log lines.
// - Bug reports are sent as a POST over HTTPS: it purposefully does not use Matrix as bug reports may be made when Matrix is
// not responsive (which may be the cause of the bug). We send the most recent N MB of UTF-8 log data, starting with the most
// recent, which we know because the "ID"s are actually timestamps. We then purge the remaining logs. We also do this check
// recent, which we know because the "ID"s are actually timestamps. We then purge the remaining logs. We also do this purge
// on startup to prevent logs from accumulating.
const FLUSH_RATE_MS = 30 * 1000;
@ -38,6 +38,7 @@ class ConsoleLogger {
const consoleFunctionsToLevels = {
log: "I",
info: "I",
warn: "W",
error: "E",
};
Object.keys(consoleFunctionsToLevels).forEach((fnName) => {
@ -110,6 +111,12 @@ class IndexedDBLogStore {
const objectStore = db.createObjectStore("logs", {
keyPath: ["id", "index"]
});
// Keys in the database look like: [ "instance-148938490", 0 ]
// Later on we need to query for everything with index=0, and query everything for an instance id.
// In order to do this, we need to set up indexes on both "id" and "index".
objectStore.createIndex("index", "index", { unique: false });
objectStore.createIndex("id", "id", { unique: false });
objectStore.add(
this._generateLogEntry(
new Date() + " ::: Log database was created."
@ -161,9 +168,11 @@ class IndexedDBLogStore {
const MAX_LOG_SIZE = 1024 * 1024 * 50; // 50 MB
// To gather all the logs, we first query for every log entry with index "0", this will let us
// know all the IDs from different tabs/sessions.
return new Promise((resolve, reject) => {
// let txn = this.db.transaction("logs", "readonly");
// let objectStore = txn.objectStore("logs");
const txn = this.db.transaction("logs", "readonly");
const objectStore = txn.objectStore("logs");
return selectQuery(objectStore.index("index"), IDBKeyRange.only(0), (cursor) => cursor.value.id).then((res) => {
console.log("Instances: ", res);
});
// we know each entry has a unique ID, and we know IDs are timestamps, so accumulate all the IDs,
// ignoring the logs for now, and sort them to work out the correct log ID ordering.
@ -175,7 +184,6 @@ class IndexedDBLogStore {
// Remove all logs that are older than the cutoff (or the entire logs if clearAll is set).
// Return the logs that are within the cutoff.
});
}
_generateLogEntry(lines) {
@ -187,6 +195,34 @@ class IndexedDBLogStore {
}
}
/**
* Helper method to collect results from a Cursor and promiseify it.
* @param {ObjectStore|Index} store The store to perform openCursor on.
* @param {IDBKeyRange=} keyRange Optional key range to apply on the cursor.
* @param {Function} resultMapper A function which is repeatedly called with a Cursor.
* Return the data you want to keep.
* @return {Promise<T[]>} Resolves to an array of whatever you returned from resultMapper.
*/
function selectQuery(store, keyRange, resultMapper) {
const query = store.openCursor(keyRange);
return new Promise((resolve, reject) => {
let results = [];
query.onerror = (event) => {
reject(new Error("Query failed: " + event.target.errorCode));
};
// collect results
query.onsuccess = (event) => {
const cursor = event.target.result;
if (!cursor) {
resolve(results);
return; // end of results
}
results.push(resultMapper(cursor));
cursor.continue();
}
});
}
let store = null;
let inited = false;