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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/. */
// A doctor for our collections. She can be asked to make a consultation, and
// may just diagnose an issue without attempting to cure it, may diagnose and
// attempt to cure, or may decide she is overworked and underpaid.
// Or something - naming is hard :)
import { Log } from "resource://gre/modules/Log.sys.mjs";
import { Async } from "resource://services-common/async.sys.mjs";
import { Observers } from "resource://services-common/observers.sys.mjs";
import { Service } from "resource://services-sync/service.sys.mjs";
import { Resource } from "resource://services-sync/resource.sys.mjs";
import { Svc } from "resource://services-sync/util.sys.mjs";
const log = Log.repository.getLogger("Sync.Doctor");
export var Doctor = {
async consult(recentlySyncedEngines) {
if (!Services.telemetry.canRecordBase) {
log.info("Skipping consultation: telemetry reporting is disabled");
return;
}
let engineInfos = this._getEnginesToValidate(recentlySyncedEngines);
await this._runValidators(engineInfos);
},
_getEnginesToValidate(recentlySyncedEngines) {
let result = {};
for (let e of recentlySyncedEngines) {
let prefPrefix = `engine.${e.name}.`;
if (
!Svc.PrefBranch.getBoolPref(prefPrefix + "validation.enabled", false)
) {
log.info(`Skipping check of ${e.name} - disabled via preferences`);
continue;
}
// Check the last validation time for the engine.
let lastValidation = Svc.PrefBranch.getIntPref(
prefPrefix + "validation.lastTime",
0
);
let validationInterval = Svc.PrefBranch.getIntPref(
prefPrefix + "validation.interval"
);
let nowSeconds = this._now();
if (nowSeconds - lastValidation < validationInterval) {
log.info(
`Skipping validation of ${e.name}: too recent since last validation attempt`
);
continue;
}
// Update the time now, even if we decline to actually perform a
// validation. We don't want to check the rest of these more frequently
// than once a day.
Svc.PrefBranch.setIntPref(
prefPrefix + "validation.lastTime",
Math.floor(nowSeconds)
);
// Validation only occurs a certain percentage of the time.
let validationProbability =
Svc.PrefBranch.getIntPref(
prefPrefix + "validation.percentageChance",
0
) / 100.0;
if (validationProbability < Math.random()) {
log.info(
`Skipping validation of ${e.name}: Probability threshold not met`
);
continue;
}
let maxRecords = Svc.PrefBranch.getIntPref(
prefPrefix + "validation.maxRecords"
);
if (!maxRecords) {
log.info(`Skipping validation of ${e.name}: No maxRecords specified`);
continue;
}
// OK, so this is a candidate - the final decision will be based on the
// number of records actually found.
result[e.name] = { engine: e, maxRecords };
}
return result;
},
async _runValidators(engineInfos) {
if (!Object.keys(engineInfos).length) {
log.info("Skipping validation: no engines qualify");
return;
}
if (Object.values(engineInfos).filter(i => i.maxRecords != -1).length) {
// at least some of the engines have maxRecord restrictions which require
// us to ask the server for the counts.
let countInfo = await this._fetchCollectionCounts();
for (let [engineName, recordCount] of Object.entries(countInfo)) {
if (engineName in engineInfos) {
engineInfos[engineName].recordCount = recordCount;
}
}
}
for (let [
engineName,
{ engine, maxRecords, recordCount },
] of Object.entries(engineInfos)) {
// maxRecords of -1 means "any number", so we can skip asking the server.
// Used for tests.
if (maxRecords >= 0 && recordCount > maxRecords) {
log.debug(
`Skipping validation for ${engineName} because ` +
`the number of records (${recordCount}) is greater ` +
`than the maximum allowed (${maxRecords}).`
);
continue;
}
let validator = engine.getValidator();
if (!validator) {
// This is probably only possible in profile downgrade cases.
log.warn(
`engine.getValidator returned null for ${engineName} but the pref that controls validation is enabled.`
);
continue;
}
if (!(await validator.canValidate())) {
log.debug(
`Skipping validation for ${engineName} because validator.canValidate() is false`
);
continue;
}
// Let's do it!
Services.console.logStringMessage(
`Sync is about to run a consistency check of ${engine.name}. This may be slow, and ` +
`can be controlled using the pref "services.sync.${engine.name}.validation.enabled".\n` +
`If you encounter any problems because of this, please file a bug.`
);
try {
log.info(`Running validator for ${engine.name}`);
let result = await validator.validate(engine);
let { problems, version, duration, recordCount } = result;
Observers.notify(
"weave:engine:validate:finish",
{
version,
checked: recordCount,
took: duration,
problems: problems ? problems.getSummary(true) : null,
},
engine.name
);
} catch (ex) {
if (Async.isShutdownException(ex)) {
throw ex;
}
log.error(`Failed to run validation on ${engine.name}!`, ex);
Observers.notify("weave:engine:validate:error", ex, engine.name);
// Keep validating -- there's no reason to think that a failure for one
// validator would mean the others will fail.
}
}
},
// mainly for mocking.
async _fetchCollectionCounts() {
let collectionCountsURL = Service.userBaseURL + "info/collection_counts";
try {
let infoResp = await Service._fetchInfo(collectionCountsURL);
if (!infoResp.success) {
log.error(
"Can't fetch collection counts: request to info/collection_counts responded with " +
infoResp.status
);
return {};
}
return infoResp.obj; // might throw because obj is a getter which parses json.
} catch (ex) {
if (Async.isShutdownException(ex)) {
throw ex;
}
// Not running validation is totally fine, so we just write an error log and return.
log.error("Caught error when fetching counts", ex);
return {};
}
},
// functions used so tests can mock them
_now() {
// We use the server time, which is SECONDS
return Resource.serverTime;
},
};