diff --git a/packages/apollo-gateway/src/__tests__/integration/networkRequests.test.ts b/packages/apollo-gateway/src/__tests__/integration/networkRequests.test.ts index bd15db3c92d..df976f8029a 100644 --- a/packages/apollo-gateway/src/__tests__/integration/networkRequests.test.ts +++ b/packages/apollo-gateway/src/__tests__/integration/networkRequests.test.ts @@ -102,7 +102,6 @@ afterEach(() => { expect(nock.isDone()).toBeTruthy(); nock.cleanAll(); nock.restore(); - jest.useRealTimers(); }); it('Queries remote endpoints for their SDLs', async () => { @@ -399,21 +398,44 @@ describe('Downstream service health checks', () => { let resolve: () => void; const schemaChangeBlocker = new Promise(res => (resolve = res)); - const onChange = jest - .fn() - .mockImplementationOnce(() => resolve()) - const gateway = new ApolloGateway({ serviceHealthCheck: true, logger }); // @ts-ignore for testing purposes, a short pollInterval is ideal so we'll override here - gateway.experimental_pollInterval = 300; + gateway.experimental_pollInterval = 100; + // load the gateway as usual await gateway.load({ engine: { apiKeyHash, graphId } }); - gateway.onSchemaChange(onChange); + expect(gateway.schema!.getType('User')!.description).toBe('This is my User'); + + // @ts-ignore for testing purposes, we'll call the original `updateComposition` + // function from our mock + const original = gateway.updateComposition; + const mockUpdateComposition = jest + .fn(original) + .mockImplementationOnce(async opts => { + // mock the first poll and handle the error which would otherwise be caught + // and logged from within the `pollServices` class method + await expect(original.apply(gateway, [opts])) + .rejects + .toThrowErrorMatchingInlineSnapshot( + `"500: Internal Server Error"`, + ); + // finally resolve the promise which drives this test + resolve(); + }); + + // @ts-ignore for testing purposes, replace the `updateComposition` + // function on the gateway with our mock + gateway.updateComposition = mockUpdateComposition; + + // This kicks off polling within the gateway + gateway.onSchemaChange(() => {}); await schemaChangeBlocker; - expect(onChange.mock.calls.length).toBe(1); + // At this point, the mock update should have been called but the schema + // should not have updated to the new one. + expect(mockUpdateComposition.mock.calls.length).toBe(1); expect(gateway.schema!.getType('User')!.description).toBe('This is my User'); }); - }) + }); }); diff --git a/packages/apollo-gateway/src/index.ts b/packages/apollo-gateway/src/index.ts index e10dfdcdeb2..edfa1e38e5e 100644 --- a/packages/apollo-gateway/src/index.ts +++ b/packages/apollo-gateway/src/index.ts @@ -379,8 +379,6 @@ export class ApolloGateway implements GraphQLService { 'The gateway did not update its schema due to failed service health checks. ' + 'The gateway will continue to operate with the previous schema and reattempt updates.' + e ); - // TODO: Questionable notify here, but it does enable code-driven testing via schema listener callbacks - this.notifySchemaListeners(this.schema); throw e; } } @@ -391,7 +389,15 @@ export class ApolloGateway implements GraphQLService { if (this.queryPlanStore) this.queryPlanStore.flush(); this.schema = this.createSchema(result.serviceDefinitions); - this.notifySchemaListeners(this.schema); + + // Notify the schema listeners of the updated schema + try { + this.onSchemaChangeListeners.forEach(listener => listener(this.schema!)); + } catch (e) { + this.logger.error( + "An error was thrown from an 'onSchemaChange' listener. " + + "The schema will still update: " + (e && e.message || e)); + } if (this.experimental_didUpdateComposition) { this.experimental_didUpdateComposition( @@ -414,16 +420,6 @@ export class ApolloGateway implements GraphQLService { } } - private notifySchemaListeners(schema?: GraphQLSchema) { - try { - this.onSchemaChangeListeners.forEach(listener => listener(schema!)); - } catch (e) { - this.logger.error( - "An error was thrown from an 'onSchemaChange' listener. " + - "The schema will still update: " + (e && e.message || e)); - } - } - /** * This can be used without an argument in order to perform an ad-hoc health check * of the downstream services like so: @@ -780,7 +776,7 @@ export class ApolloGateway implements GraphQLService { public async stop() { if (this.pollingTimer) { - clearInterval(this.pollingTimer); + clearTimeout(this.pollingTimer); this.pollingTimer = undefined; } }