Add graceful shutdown to worker

This commit is contained in:
Jan Oberhauser 2021-01-01 09:18:45 +01:00
parent d324082021
commit 6fb6b509e5

View file

@ -15,6 +15,7 @@ import {
} from 'n8n-workflow';
import {
ActiveExecutions,
CredentialsOverwrites,
CredentialTypes,
Db,
@ -41,15 +42,65 @@ export class Worker extends Command {
static flags = {
help: flags.help({ char: 'h' }),
concurrency: flags.integer({
default: 10,
// default: 10,
// TODO: Change setting
default: 1,
description: 'How many jobs can run in parallel.',
}),
};
runningJobs: {
static runningJobs: {
[key: string]: PCancelable<IRun>;
} = {};
static jobQueue: Bull.Queue;
static processExistCode = 0;
// static activeExecutions = ActiveExecutions.getInstance();
/**
* Stoppes the n8n in a graceful way.
* Make for example sure that all the webhooks from third party services
* get removed.
*/
static async stopProcess() {
console.log(`\nStopping n8n...`);
// Stop accepting new jobs
Worker.jobQueue.pause(true);
try {
const externalHooks = ExternalHooks();
await externalHooks.run('n8n.stop', []);
const maxStopTime = 30000;
const stopTime = new Date().getTime() + maxStopTime;
setTimeout(() => {
// In case that something goes wrong with shutdown we
// kill after max. 30 seconds no matter what
process.exit(Worker.processExistCode);
}, maxStopTime);
// Wait for active workflow executions to finish
let count = 0;
while (Object.keys(Worker.runningJobs).length !== 0) {
if (count++ % 4 === 0) {
let waitLeft = Math.ceil((stopTime - new Date().getTime()) / 1000);
console.log(`Waiting for ${Object.keys(Worker.runningJobs).length} active executions to finish... (wait ${waitLeft} more seconds)`);
}
await new Promise((resolve) => {
setTimeout(resolve, 500);
});
}
} catch (error) {
console.error('There was an error shutting down n8n.', error);
}
process.exit(Worker.processExistCode);
}
getWorkflowHooks(jobData: IBullJobData, executionId: string): WorkflowHooks {
const hookFunctions: IWorkflowExecuteHooks = {};
@ -72,7 +123,6 @@ export class Worker extends Command {
console.log(`Start job: ${job.id} (Workflow ID: ${jobData.workflowData.id})`);
// TODO: Can in the future query most of that data from the DB to lighten redis load
const workflow = new Workflow({ id: jobData.workflowData.id as string, name: jobData.workflowData.name, nodes: jobData.workflowData!.nodes, connections: jobData.workflowData!.connections, active: jobData.workflowData!.active, nodeTypes, staticData: jobData.workflowData!.staticData, settings: jobData.workflowData!.settings });
const credentials = await WorkflowCredentials(jobData.workflowData.nodes);
@ -97,12 +147,12 @@ export class Worker extends Command {
workflowRun = workflowExecute.runPartialWorkflow(workflow, jobData.runData, jobData.startNodes, jobData.destinationNode);
}
this.runningJobs[job.id] = workflowRun;
Worker.runningJobs[job.id] = workflowRun;
// Wait till the execution is finished
const runData = await workflowRun;
delete this.runningJobs[job.id];
delete Worker.runningJobs[job.id];
return {
runData,
@ -112,79 +162,82 @@ export class Worker extends Command {
async run() {
console.log('Starting n8n worker...');
try {
const { flags } = this.parse(Worker);
// Make sure that n8n shuts down gracefully if possible
process.on('SIGTERM', Worker.stopProcess);
process.on('SIGINT', Worker.stopProcess);
// Start directly with the init of the database to improve startup time
const startDbInitPromise = Db.init().catch(error => {
console.error(`There was an error initializing DB: ${error.message}`);
// Wrap that the process does not close but we can still use async
await (async () => {
try {
const { flags } = this.parse(Worker);
// Start directly with the init of the database to improve startup time
const startDbInitPromise = Db.init().catch(error => {
console.error(`There was an error initializing DB: ${error.message}`);
Worker.processExistCode = 1;
// @ts-ignore
process.emit('SIGINT');
});
// Make sure the settings exist
await UserSettings.prepareUserSettings();
// Load all node and credential types
const loadNodesAndCredentials = LoadNodesAndCredentials();
await loadNodesAndCredentials.init();
// Load the credentials overwrites if any exist
const credentialsOverwrites = CredentialsOverwrites();
await credentialsOverwrites.init();
// Load all external hooks
const externalHooks = ExternalHooks();
await externalHooks.init();
// Add the found types to an instance other parts of the application can use
const nodeTypes = NodeTypes();
await nodeTypes.init(loadNodesAndCredentials.nodeTypes);
const credentialTypes = CredentialTypes();
await credentialTypes.init(loadNodesAndCredentials.credentialTypes);
// Wait till the database is ready
await startDbInitPromise;
// Connect to bull-queue
const prefix = config.get('queue.bull.prefix') as string;
const redisOptions = config.get('queue.bull.redis') as object;
Worker.jobQueue = new Bull('jobs', { prefix, redis: redisOptions });
Worker.jobQueue.process(flags.concurrency, (job) => this.runJob(job, nodeTypes));
const versions = await GenericHelpers.getVersions();
console.log('\nn8n worker is now ready');
console.log(` * Version: ${versions.cli}`);
console.log(` * Concurrency: ${flags.concurrency}`);
console.log('');
Worker.jobQueue.on('global:progress', (jobId, progress) => {
// Progress of a job got updated which does get used
// to communicate that a job got canceled.
if (progress === -1) {
// Job has to get canceled
if (Worker.runningJobs[jobId] !== undefined) {
// Job is processed by current worker so cancel
Worker.runningJobs[jobId].cancel();
delete Worker.runningJobs[jobId];
}
}
});
} catch (error) {
this.error(`There was an error: ${error.message}`);
Worker.processExistCode = 1;
// @ts-ignore
process.emit('SIGINT');
});
}
})();
// Make sure the settings exist
await UserSettings.prepareUserSettings();
// Load all node and credential types
const loadNodesAndCredentials = LoadNodesAndCredentials();
await loadNodesAndCredentials.init();
// Load the credentials overwrites if any exist
const credentialsOverwrites = CredentialsOverwrites();
await credentialsOverwrites.init();
// Load all external hooks
const externalHooks = ExternalHooks();
await externalHooks.init();
// Add the found types to an instance other parts of the application can use
const nodeTypes = NodeTypes();
await nodeTypes.init(loadNodesAndCredentials.nodeTypes);
const credentialTypes = CredentialTypes();
await credentialTypes.init(loadNodesAndCredentials.credentialTypes);
// Wait till the database is ready
await startDbInitPromise;
// Connect to bull-queue
const prefix = config.get('queue.bull.prefix') as string;
const redisOptions = config.get('queue.bull.redis') as object;
const jobQueue = new Bull('jobs', { prefix, redis: redisOptions });
jobQueue.process(flags.concurrency, (job) => this.runJob(job, nodeTypes));
const versions = await GenericHelpers.getVersions();
console.log('\nn8n worker is now ready');
console.log(` * Version: ${versions.cli}`);
console.log(` * Concurrency: ${flags.concurrency}`);
console.log('');
jobQueue.on('global:progress', (jobId, progress) => {
// Progress of a job got updated which does get used
// to communicate that a job got canceled.
if (progress === -1) {
// Job has to get canceled
if (this.runningJobs[jobId] !== undefined) {
// Job is processed by current worker so cancel
this.runningJobs[jobId].cancel();
delete this.runningJobs[jobId];
}
}
});
} catch (e) {
// TODO: Do some testing here how to really display the error
// this.error(`There was an error: ${error.message}`);
console.error('\nGOT ERROR');
console.log('====================================');
console.error(e.message);
console.error(e.stack);
// @ts-ignore
process.emit('SIGINT');
}
}
}