fix(aio): ensure that only one request per document is made

This commit is contained in:
Peter Bacon Darwin 2017-03-04 16:05:37 +00:00 committed by Igor Minar
parent b44bc9c022
commit 66cc88c8a8
2 changed files with 127 additions and 22 deletions

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@ -1,31 +1,132 @@
import { ReflectiveInjector } from '@angular/core'; import { ReflectiveInjector } from '@angular/core';
import { Location, LocationStrategy } from '@angular/common'; import { Http, ConnectionBackend, RequestOptions, BaseRequestOptions, Response, ResponseOptions } from '@angular/http';
import { MockLocationStrategy } from '@angular/common/testing';
import { Http, ConnectionBackend, RequestOptions, BaseRequestOptions } from '@angular/http'; import { Observable } from 'rxjs/Observable';
import { Subscription } from 'rxjs/Subscription';
import { BehaviorSubject } from 'rxjs/BehaviorSubject';
import { MockBackend } from '@angular/http/testing'; import { MockBackend } from '@angular/http/testing';
import { LocationService } from 'app/shared/location.service'; import { LocationService } from 'app/shared/location.service';
import { MockLocationService } from 'testing/location.service';
import { Logger } from 'app/shared/logger.service'; import { Logger } from 'app/shared/logger.service';
import { DocumentService } from './document.service'; import { MockLogger } from 'testing/logger.service';
import { DocumentService, DocumentContents } from './document.service';
const CONTENT_URL_PREFIX = 'content/docs/';
function createResponse(body: any) {
return new Response(new ResponseOptions({ body: JSON.stringify(body) }));
}
function createInjector(initialUrl: string) {
return ReflectiveInjector.resolveAndCreate([
DocumentService,
{ provide: LocationService, useFactory: () => new MockLocationService(initialUrl) },
{ provide: ConnectionBackend, useClass: MockBackend },
{ provide: RequestOptions, useClass: BaseRequestOptions },
{ provide: Logger, useClass: MockLogger },
Http,
]);
}
function getServices(initialUrl: string = '') {
const injector = createInjector(initialUrl);
return {
backend: injector.get(ConnectionBackend) as MockBackend,
location: injector.get(LocationService) as MockLocationService,
service: injector.get(DocumentService) as DocumentService,
logger: injector.get(Logger) as MockLogger
};
}
describe('DocumentService', () => { describe('DocumentService', () => {
let injector: ReflectiveInjector;
beforeEach(() => {
injector = ReflectiveInjector.resolveAndCreate([
DocumentService,
LocationService,
Location,
{ provide: LocationStrategy, useClass: MockLocationStrategy },
{ provide: ConnectionBackend, useClass: MockBackend },
{ provide: RequestOptions, useClass: BaseRequestOptions },
Http,
Logger
]);
});
it('should be creatable', () => { it('should be creatable', () => {
const service: DocumentService = injector.get(DocumentService); const { service } = getServices();
expect(service).toBeTruthy(); expect(service).toBeTruthy();
}); });
describe('currentDocument', () => {
it('should fetch a document for the initial location url', () => {
const { service, backend } = getServices('initial/url');
const connections = backend.connectionsArray;
service.currentDocument.subscribe();
expect(connections.length).toEqual(1);
expect(connections[0].request.url).toEqual(CONTENT_URL_PREFIX + 'initial/url.json');
expect(backend.connectionsArray[0].request.url).toEqual(CONTENT_URL_PREFIX + 'initial/url.json');
});
it('should emit a document each time the location changes', () => {
let latestDocument: DocumentContents;
const doc0 = { title: 'doc 0' };
const doc1 = { title: 'doc 1' };
const { service, backend, location } = getServices('initial/url');
const connections = backend.connectionsArray;
service.currentDocument.subscribe(doc => latestDocument = doc);
expect(latestDocument).toBeUndefined();
connections[0].mockRespond(createResponse(doc0));
expect(latestDocument).toEqual(doc0);
location.urlSubject.next('new/url');
connections[1].mockRespond(createResponse(doc1));
expect(latestDocument).toEqual(doc1);
});
it('should emit the not-found document if the document is not found on the server', () => {
});
it('should not make a request to the server if the doc is in the cache already', () => {
let latestDocument: DocumentContents;
let subscription: Subscription;
const doc0 = { title: 'doc 0' };
const doc1 = { title: 'doc 1' };
const { service, backend, location } = getServices('url/0');
const connections = backend.connectionsArray;
subscription = service.currentDocument.subscribe(doc => latestDocument = doc);
expect(connections.length).toEqual(1);
connections[0].mockRespond(createResponse(doc0));
expect(latestDocument).toEqual(doc0);
subscription.unsubscribe();
// modify the response so we can check that future subscriptions do not trigger another request
connections[0].response.next(createResponse({ title: 'error 0' }));
subscription = service.currentDocument.subscribe(doc => latestDocument = doc);
location.urlSubject.next('url/1');
expect(connections.length).toEqual(2);
connections[1].mockRespond(createResponse(doc1));
expect(latestDocument).toEqual(doc1);
subscription.unsubscribe();
// modify the response so we can check that future subscriptions do not trigger another request
connections[1].response.next(createResponse({ title: 'error 1' }));
subscription = service.currentDocument.subscribe(doc => latestDocument = doc);
location.urlSubject.next('url/0');
expect(connections.length).toEqual(2);
expect(latestDocument).toEqual(doc0);
subscription.unsubscribe();
subscription = service.currentDocument.subscribe(doc => latestDocument = doc);
location.urlSubject.next('url/1');
expect(connections.length).toEqual(2);
expect(latestDocument).toEqual(doc1);
subscription.unsubscribe();
});
it('should map the "empty" location to the correct document request', () => {
let latestDocument: DocumentContents;
const { service, backend } = getServices();
service.currentDocument.subscribe(doc => latestDocument = doc);
});
});
}); });

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@ -2,6 +2,7 @@ import { Injectable } from '@angular/core';
import { Http, Response } from '@angular/http'; import { Http, Response } from '@angular/http';
import { Observable } from 'rxjs/Observable'; import { Observable } from 'rxjs/Observable';
import { AsyncSubject } from 'rxjs/AsyncSubject';
import 'rxjs/add/operator/switchMap'; import 'rxjs/add/operator/switchMap';
import { LocationService } from 'app/shared/location.service'; import { LocationService } from 'app/shared/location.service';
@ -37,7 +38,8 @@ export class DocumentService {
private fetchDocument(url: string) { private fetchDocument(url: string) {
const path = this.computePath(url); const path = this.computePath(url);
this.logger.log('fetching document from', path); this.logger.log('fetching document from', path);
return this.http const subject = new AsyncSubject();
this.http
.get(path) .get(path)
.map(res => res.json()) .map(res => res.json())
.catch((error: Response) => { .catch((error: Response) => {
@ -48,7 +50,9 @@ export class DocumentService {
} else { } else {
throw error; throw error;
} }
}); })
.subscribe(subject);
return subject.asObservable();
} }
private computePath(url) { private computePath(url) {