Merge pull request #1095 from balena-io/roman/error-handling

Unify API errors processing

src/api-binder.ts

@@ -935,7 +935,7 @@ export class APIBinder {
 		router.use(bodyParser.urlencoded({ limit: '10mb', extended: true }));
 		router.use(bodyParser.json({ limit: '10mb' }));
 
-		router.post('/v1/update', (req, res) => {
+		router.post('/v1/update', (req, res, next) => {
 			apiBinder.eventTracker.track('Update notification');
 			if (apiBinder.readyForUpdates) {
 				this.config
@@ -953,15 +953,7 @@ export class APIBinder {
 							res.sendStatus(202);
 						}
 					})
-					.catch(err => {
+					.catch(next);
-						const msg =
-							err.message != null
-								? err.message
-								: err != null
-								? err
-								: 'Unknown error';
-						res.status(503).send(msg);
-					});
 			} else {
 				res.sendStatus(202);
 			}

src/device-api/v1.coffee

@@ -9,7 +9,7 @@ exports.createV1Api = (router, applications) ->
 
 	{ eventTracker } = applications
 
-	router.post '/v1/restart', (req, res) ->
+	router.post '/v1/restart', (req, res, next) ->
 		appId = checkInt(req.body.appId)
 		force = checkTruthy(req.body.force)
 		eventTracker.track('Restart container (v1)', { appId })
@@ -18,10 +18,9 @@ exports.createV1Api = (router, applications) ->
 		doRestart(applications, appId, force)
 		.then ->
 			res.status(200).send('OK')
-		.catch (err) ->
+		.catch(next)
-			res.status(503).send(err?.message or err or 'Unknown error')
 
-	v1StopOrStart = (req, res, action) ->
+	v1StopOrStart = (req, res, next, action) ->
 		appId = checkInt(req.params.appId)
 		force = checkTruthy(req.body.force)
 		if !appId?
@@ -47,16 +46,14 @@ exports.createV1Api = (router, applications) ->
 					return service
 			.then (service) ->
 				res.status(200).json({ containerId: service.containerId })
-		.catch (err) ->
+		.catch(next)
-			res.status(503).send(err?.message or err or 'Unknown error')
 
-	router.post '/v1/apps/:appId/stop', (req, res) ->
+	createV1StopOrStartHandler = (action) -> _.partial(v1StopOrStart, _, _, _, action)
-		v1StopOrStart(req, res, 'stop')
 
-	router.post '/v1/apps/:appId/start', (req, res) ->
+	router.post('/v1/apps/:appId/stop', createV1StopOrStartHandler('stop'))
-		v1StopOrStart(req, res, 'start')
+	router.post('/v1/apps/:appId/start', createV1StopOrStartHandler('start'))
 
-	router.get '/v1/apps/:appId', (req, res) ->
+	router.get '/v1/apps/:appId', (req, res, next) ->
 		appId = checkInt(req.params.appId)
 		eventTracker.track('GET app (v1)', { appId })
 		if !appId?
@@ -82,10 +79,9 @@ exports.createV1Api = (router, applications) ->
 					appToSend.commit = status.commit
 				res.json(appToSend)
 		)
-		.catch (err) ->
+		.catch(next)
-			res.status(503).send(err?.message or err or 'Unknown error')
 
-	router.post '/v1/purge', (req, res) ->
+	router.post '/v1/purge', (req, res, next) ->
 		appId = checkInt(req.body.appId)
 		force = checkTruthy(req.body.force)
 		if !appId?
@@ -94,6 +90,4 @@ exports.createV1Api = (router, applications) ->
 		doPurge(applications, appId, force)
 		.then ->
 			res.status(200).json(Data: 'OK', Error: '')
-		.catch (err) ->
+		.catch(next)
-			res.status(503).send(err?.message or err or 'Unknown error')
-

src/device-api/v2.ts

@@ -1,5 +1,5 @@
 import * as Bluebird from 'bluebird';
-import { Request, Response, Router } from 'express';
+import { NextFunction, Request, Response, Router } from 'express';
 import * as _ from 'lodash';
 import { fs } from 'mz';
 
@@ -22,21 +22,10 @@ import { checkInt, checkTruthy } from '../lib/validation';
 export function createV2Api(router: Router, applications: ApplicationManager) {
 	const { _lockingIfNecessary, deviceState } = applications;
 
-	const messageFromError = (err?: Error | string | null): string => {
-		let message = 'Unknown error';
-		if (err != null) {
-			if (_.isError(err) && err.message != null) {
-				message = err.message;
-			} else {
-				message = err as string;
-			}
-		}
-		return message;
-	};
-
 	const handleServiceAction = (
 		req: Request,
 		res: Response,
+		next: NextFunction,
 		action: any,
 	): Bluebird<void> => {
 		const { imageId, serviceName, force } = req.body;
@@ -85,15 +74,16 @@ export function createV2Api(router: Router, applications: ApplicationManager) {
 							res.status(200).send('OK');
 						});
 				})
-				.catch(err => {
+				.catch(next);
-					res.status(503).send(messageFromError(err));
-				});
 		});
 	};
 
+	const createServiceActionHandler = (action: string) =>
+		_.partial(handleServiceAction, _, _, _, action);
+
 	router.post(
 		'/v2/applications/:appId/purge',
-		(req: Request, res: Response) => {
+		(req: Request, res: Response, next: NextFunction) => {
 			const { force } = req.body;
 			const { appId } = req.params;
 
@@ -101,45 +91,28 @@ export function createV2Api(router: Router, applications: ApplicationManager) {
 				.then(() => {
 					res.status(200).send('OK');
 				})
-				.catch(err => {
+				.catch(next);
-					let message;
-					if (err != null) {
-						message = err.message;
-						if (message == null) {
-							message = err;
-						}
-					} else {
-						message = 'Unknown error';
-					}
-					res.status(503).send(message);
-				});
 		},
 	);
 
 	router.post(
 		'/v2/applications/:appId/restart-service',
-		(req: Request, res: Response) => {
+		createServiceActionHandler('restart'),
-			return handleServiceAction(req, res, 'restart');
-		},
 	);
 
 	router.post(
 		'/v2/applications/:appId/stop-service',
-		(req: Request, res: Response) => {
+		createServiceActionHandler('stop'),
-			return handleServiceAction(req, res, 'stop');
-		},
 	);
 
 	router.post(
 		'/v2/applications/:appId/start-service',
-		(req: Request, res: Response) => {
+		createServiceActionHandler('start'),
-			return handleServiceAction(req, res, 'start');
-		},
 	);
 
 	router.post(
 		'/v2/applications/:appId/restart',
-		(req: Request, res: Response) => {
+		(req: Request, res: Response, next: NextFunction) => {
 			const { force } = req.body;
 			const { appId } = req.params;
 
@@ -147,14 +120,14 @@ export function createV2Api(router: Router, applications: ApplicationManager) {
 				.then(() => {
 					res.status(200).send('OK');
 				})
-				.catch(err => {
+				.catch(next);
-					res.status(503).send(messageFromError(err));
-				});
 		},
 	);
 
 	// TODO: Support dependent applications when this feature is complete
-	router.get('/v2/applications/state', async (_req: Request, res: Response) => {
+	router.get(
+		'/v2/applications/state',
+		async (_req: Request, res: Response, next: NextFunction) => {
 			// It's kinda hacky to access the services and db via the application manager
 			// maybe refactor this code
 			Bluebird.join(
@@ -224,21 +197,24 @@ export function createV2Api(router: Router, applications: ApplicationManager) {
 
 					res.status(200).json(response);
 				},
+			).catch(next);
+		},
 	);
-	});
 
 	router.get(
 		'/v2/applications/:appId/state',
-		(_req: Request, res: Response) => {
+		(_req: Request, res: Response, next: NextFunction) => {
 			// Get all services and their statuses, and return it
-			applications.getStatus().then(apps => {
+			applications
+				.getStatus()
+				.then(apps => {
 					res.status(200).json(apps);
-			});
+				})
+				.catch(next);
 		},
 	);
 
 	router.get('/v2/local/target-state', async (_req, res) => {
-		try {
 		const localMode = await deviceState.config.get('localMode');
 		if (!localMode) {
 			return res.status(400).json({
@@ -292,18 +268,11 @@ export function createV2Api(router: Router, applications: ApplicationManager) {
 			status: 'success',
 			state: target,
 		});
-		} catch (err) {
-			res.status(503).send({
-				status: 'failed',
-				message: messageFromError(err),
-			});
-		}
 	});
 
 	router.post('/v2/local/target-state', async (req, res) => {
 		// let's first ensure that we're in local mode, otherwise
 		// this function should not do anything
-		try {
 		const localMode = await deviceState.config.get('localMode');
 		if (!localMode) {
 			return res.status(400).json({
@@ -328,19 +297,11 @@ export function createV2Api(router: Router, applications: ApplicationManager) {
 				message: e.message,
 			});
 		}
-		} catch (e) {
-			const message = 'Could not apply target state: ';
-			res.status(503).json({
-				status: 'failed',
-				message: message + messageFromError(e),
-			});
-		}
 	});
 
 	router.get('/v2/local/device-info', async (_req, res) => {
 		// Return the device type and slug so that local mode builds can use this to
 		// resolve builds
-		try {
 		// FIXME: We should be mounting the following file into the supervisor from the
 		// start-resin-supervisor script, changed in meta-resin - but until then, hardcode it
 		const data = await fs.readFile(
@@ -356,13 +317,6 @@ export function createV2Api(router: Router, applications: ApplicationManager) {
 				deviceType: deviceInfo.slug,
 			},
 		});
-		} catch (e) {
-			const message = 'Could not fetch device information: ';
-			res.status(503).json({
-				status: 'failed',
-				message: message + messageFromError(e),
-			});
-		}
 	});
 
 	router.get('/v2/local/logs', async (_req, res) => {
@@ -392,15 +346,11 @@ export function createV2Api(router: Router, applications: ApplicationManager) {
 	});
 
 	router.get('/v2/containerId', async (req, res) => {
-		try {
 		const services = await applications.services.getAll();
 
 		if (req.query.serviceName != null || req.query.service != null) {
 			const serviceName = req.query.serviceName || req.query.service;
-				const service = _.find(
+			const service = _.find(services, svc => svc.serviceName === serviceName);
-					services,
-					svc => svc.serviceName === serviceName,
-				);
 			if (service != null) {
 				res.status(200).json({
 					status: 'success',
@@ -421,12 +371,6 @@ export function createV2Api(router: Router, applications: ApplicationManager) {
 					.value(),
 			});
 		}
-		} catch (e) {
-			res.status(503).json({
-				status: 'failed',
-				message: messageFromError(e),
-			});
-		}
 	});
 
 	router.get('/v2/state/status', async (_req, res) => {
@@ -481,60 +425,36 @@ export function createV2Api(router: Router, applications: ApplicationManager) {
 	});
 
 	router.get('/v2/device/name', async (_req, res) => {
-		try {
 		const deviceName = await applications.config.get('name');
 		res.json({
 			status: 'success',
 			deviceName,
 		});
-		} catch (e) {
-			res.status(503).json({
-				status: 'failed',
-				message: messageFromError(e),
-			});
-		}
 	});
 
 	router.get('/v2/device/tags', async (_req, res) => {
-		try {
 		const tags = await applications.apiBinder.fetchDeviceTags();
 		return res.json({
 			status: 'success',
 			tags,
 		});
-		} catch (e) {
-			res.status(503).json({
-				status: 'failed',
-				message: messageFromError(e),
-			});
-		}
 	});
 
 	router.get('/v2/cleanup-volumes', async (_req, res) => {
-		try {
 		const targetState = await applications.getTargetApps();
 		const referencedVolumes: string[] = [];
 		_.each(targetState, app => {
 			_.each(app.volumes, vol => {
-					referencedVolumes.push(
+				referencedVolumes.push(Volume.generateDockerName(vol.appId, vol.name));
-						Volume.generateDockerName(vol.appId, vol.name),
-					);
 			});
 		});
 		await applications.volumes.removeOrphanedVolumes(referencedVolumes);
 		res.json({
 			status: 'success',
 		});
-		} catch (e) {
-			res.status(503).json({
-				status: 'failed',
-				message: messageFromError(e),
-			});
-		}
 	});
 
 	router.post('/v2/journal-logs', (req, res) => {
-		try {
 		const all = checkTruthy(req.body.all) || false;
 		const follow = checkTruthy(req.body.follow) || false;
 		const count = checkInt(req.body.count, { positive: true }) || undefined;
@@ -551,15 +471,5 @@ export function createV2Api(router: Router, applications: ApplicationManager) {
 			journald.stdout.unpipe();
 			res.end();
 		});
-		} catch (e) {
-			log.error('There was an error reading the journalctl process', e);
-			if (res.headersSent) {
-				return;
-			}
-			res.json({
-				status: 'failed',
-				message: messageFromError(e),
-			});
-		}
 	});
 }

src/supervisor-api.ts

@@ -1,3 +1,4 @@
+import { NextFunction, Request, Response } from 'express';
 import * as express from 'express';
 import { Server } from 'http';
 import * as _ from 'lodash';
@@ -102,15 +103,11 @@ export class SupervisorAPI {
 		this.api.use(expressLogger);
 
 		this.api.get('/v1/healthy', async (_req, res) => {
-			try {
 			const healths = await Promise.all(this.healthchecks.map(fn => fn()));
 			if (!_.every(healths)) {
 				throw new Error('Unhealthy');
 			}
 			return res.sendStatus(200);
-			} catch (e) {
-				res.sendStatus(500);
-			}
 		});
 
 		this.api.get('/ping', (_req, res) => res.send('OK'));
@@ -127,19 +124,44 @@ export class SupervisorAPI {
 		// Expires the supervisor's API key and generates a new one.
 		// It also communicates the new key to the balena API.
 		this.api.post('/v1/regenerate-api-key', async (_req, res) => {
-			try {
 			const secret = await this.config.newUniqueKey();
 			await this.config.set({ apiSecret: secret });
 			res.status(200).send(secret);
-			} catch (e) {
-				res.status(503).send(e != null ? e.message : e || 'Unknown error');
-			}
 		});
 
 		// And assign all external routers
 		for (const router of this.routers) {
 			this.api.use(router);
 		}
+
+		// Error handling.
+
+		const messageFromError = (err?: Error | string | null): string => {
+			let message = 'Unknown error';
+			if (err != null) {
+				if (_.isError(err) && err.message != null) {
+					message = err.message;
+				} else {
+					message = err as string;
+				}
+			}
+			return message;
+		};
+
+		this.api.use(
+			(err: Error, req: Request, res: Response, next: NextFunction) => {
+				if (res.headersSent) {
+					// Error happens while we are writing the response - default handler closes the connection.
+					next(err);
+					return;
+				}
+				log.error(`Error on ${req.method} ${req.path}: `, err);
+				res.status(503).send({
+					status: 'failed',
+					message: messageFromError(err),
+				});
+			},
+		);
 	}
 
 	public async listen(