apply_redirects.ts
/**
* @license
* Copyright Google Inc. All Rights Reserved.
*
* Use of this source code is governed by an MIT-style license that can be
* found in the LICENSE file at https://angular.io/license
*/
import {Injector, NgModuleRef} from '@angular/core';
import {EmptyError, Observable, Observer, from, of } from 'rxjs';
import {catchError, concatAll, first, map, mergeMap} from 'rxjs/operators';
import {LoadedRouterConfig, Route, Routes} from './config';
import {RouterConfigLoader} from './router_config_loader';
import {PRIMARY_OUTLET, Params, defaultUrlMatcher, navigationCancelingError} from './shared';
import {UrlSegment, UrlSegmentGroup, UrlSerializer, UrlTree} from './url_tree';
import {andObservables, forEach, waitForMap, wrapIntoObservable} from './utils/collection';
class NoMatch {
public segmentGroup: UrlSegmentGroup|null;
constructor(segmentGroup?: UrlSegmentGroup) { this.segmentGroup = segmentGroup || null; }
}
class AbsoluteRedirect {
constructor(public urlTree: UrlTree) {}
}
function noMatch(segmentGroup: UrlSegmentGroup): Observable<UrlSegmentGroup> {
return new Observable<UrlSegmentGroup>(
(obs: Observer<UrlSegmentGroup>) => obs.error(new NoMatch(segmentGroup)));
}
function absoluteRedirect(newTree: UrlTree): Observable<any> {
return new Observable<UrlSegmentGroup>(
(obs: Observer<UrlSegmentGroup>) => obs.error(new AbsoluteRedirect(newTree)));
}
function namedOutletsRedirect(redirectTo: string): Observable<any> {
return new Observable<UrlSegmentGroup>(
(obs: Observer<UrlSegmentGroup>) => obs.error(new Error(
`Only absolute redirects can have named outlets. redirectTo: '${redirectTo}'`)));
}
function canLoadFails(route: Route): Observable<LoadedRouterConfig> {
return new Observable<LoadedRouterConfig>(
(obs: Observer<LoadedRouterConfig>) => obs.error(navigationCancelingError(
`Cannot load children because the guard of the route "path: '${route.path}'" returned false`)));
}
/**
* Returns the `UrlTree` with the redirection applied.
*
* Lazy modules are loaded along the way.
*/
export function applyRedirects(
moduleInjector: Injector, configLoader: RouterConfigLoader, urlSerializer: UrlSerializer,
urlTree: UrlTree, config: Routes): Observable<UrlTree> {
return new ApplyRedirects(moduleInjector, configLoader, urlSerializer, urlTree, config).apply();
}
class ApplyRedirects {
private allowRedirects: boolean = true;
private ngModule: NgModuleRef<any>;
constructor(
moduleInjector: Injector, private configLoader: RouterConfigLoader,
private urlSerializer: UrlSerializer, private urlTree: UrlTree, private config: Routes) {
this.ngModule = moduleInjector.get(NgModuleRef);
}
apply(): Observable<UrlTree> {
const expanded$ =
this.expandSegmentGroup(this.ngModule, this.config, this.urlTree.root, PRIMARY_OUTLET);
const urlTrees$ = expanded$.pipe(
map((rootSegmentGroup: UrlSegmentGroup) => this.createUrlTree(
rootSegmentGroup, this.urlTree.queryParams, this.urlTree.fragment !)));
return urlTrees$.pipe(catchError((e: any) => {
if (e instanceof AbsoluteRedirect) {
// after an absolute redirect we do not apply any more redirects!
this.allowRedirects = false;
// we need to run matching, so we can fetch all lazy-loaded modules
return this.match(e.urlTree);
}
if (e instanceof NoMatch) {
throw this.noMatchError(e);
}
throw e;
}));
}
private match(tree: UrlTree): Observable<UrlTree> {
const expanded$ =
this.expandSegmentGroup(this.ngModule, this.config, tree.root, PRIMARY_OUTLET);
const mapped$ = expanded$.pipe(
map((rootSegmentGroup: UrlSegmentGroup) =>
this.createUrlTree(rootSegmentGroup, tree.queryParams, tree.fragment !)));
return mapped$.pipe(catchError((e: any): Observable<UrlTree> => {
if (e instanceof NoMatch) {
throw this.noMatchError(e);
}
throw e;
}));
}
private noMatchError(e: NoMatch): any {
return new Error(`Cannot match any routes. URL Segment: '${e.segmentGroup}'`);
}
private createUrlTree(rootCandidate: UrlSegmentGroup, queryParams: Params, fragment: string):
UrlTree {
const root = rootCandidate.segments.length > 0 ?
new UrlSegmentGroup([], {[PRIMARY_OUTLET]: rootCandidate}) :
rootCandidate;
return new UrlTree(root, queryParams, fragment);
}
private expandSegmentGroup(
ngModule: NgModuleRef<any>, routes: Route[], segmentGroup: UrlSegmentGroup,
outlet: string): Observable<UrlSegmentGroup> {
if (segmentGroup.segments.length === 0 && segmentGroup.hasChildren()) {
return this.expandChildren(ngModule, routes, segmentGroup)
.pipe(map((children: any) => new UrlSegmentGroup([], children)));
}
return this.expandSegment(ngModule, segmentGroup, routes, segmentGroup.segments, outlet, true);
}
// Recursively expand segment groups for all the child outlets
private expandChildren(
ngModule: NgModuleRef<any>, routes: Route[],
segmentGroup: UrlSegmentGroup): Observable<{[name: string]: UrlSegmentGroup}> {
return waitForMap(
segmentGroup.children,
(childOutlet, child) => this.expandSegmentGroup(ngModule, routes, child, childOutlet));
}
private expandSegment(
ngModule: NgModuleRef<any>, segmentGroup: UrlSegmentGroup, routes: Route[],
segments: UrlSegment[], outlet: string,
allowRedirects: boolean): Observable<UrlSegmentGroup> {
return of (...routes).pipe(
map((r: any) => {
const expanded$ = this.expandSegmentAgainstRoute(
ngModule, segmentGroup, routes, r, segments, outlet, allowRedirects);
return expanded$.pipe(catchError((e: any) => {
if (e instanceof NoMatch) {
// TODO(i): this return type doesn't match the declared Observable<UrlSegmentGroup> -
// talk to Jason
return of (null) as any;
}
throw e;
}));
}),
concatAll(), first((s: any) => !!s), catchError((e: any, _: any) => {
if (e instanceof EmptyError || e.name === 'EmptyError') {
if (this.noLeftoversInUrl(segmentGroup, segments, outlet)) {
return of (new UrlSegmentGroup([], {}));
}
throw new NoMatch(segmentGroup);
}
throw e;
}));
}
private noLeftoversInUrl(segmentGroup: UrlSegmentGroup, segments: UrlSegment[], outlet: string):
boolean {
return segments.length === 0 && !segmentGroup.children[outlet];
}
private expandSegmentAgainstRoute(
ngModule: NgModuleRef<any>, segmentGroup: UrlSegmentGroup, routes: Route[], route: Route,
paths: UrlSegment[], outlet: string, allowRedirects: boolean): Observable<UrlSegmentGroup> {
if (getOutlet(route) !== outlet) {
return noMatch(segmentGroup);
}
if (route.redirectTo === undefined) {
return this.matchSegmentAgainstRoute(ngModule, segmentGroup, route, paths);
}
if (allowRedirects && this.allowRedirects) {
return this.expandSegmentAgainstRouteUsingRedirect(
ngModule, segmentGroup, routes, route, paths, outlet);
}
return noMatch(segmentGroup);
}
private expandSegmentAgainstRouteUsingRedirect(
ngModule: NgModuleRef<any>, segmentGroup: UrlSegmentGroup, routes: Route[], route: Route,
segments: UrlSegment[], outlet: string): Observable<UrlSegmentGroup> {
if (route.path === '**') {
return this.expandWildCardWithParamsAgainstRouteUsingRedirect(
ngModule, routes, route, outlet);
}
return this.expandRegularSegmentAgainstRouteUsingRedirect(
ngModule, segmentGroup, routes, route, segments, outlet);
}
private expandWildCardWithParamsAgainstRouteUsingRedirect(
ngModule: NgModuleRef<any>, routes: Route[], route: Route,
outlet: string): Observable<UrlSegmentGroup> {
const newTree = this.applyRedirectCommands([], route.redirectTo !, {});
if (route.redirectTo !.startsWith('/')) {
return absoluteRedirect(newTree);
}
return this.lineralizeSegments(route, newTree).pipe(mergeMap((newSegments: UrlSegment[]) => {
const group = new UrlSegmentGroup(newSegments, {});
return this.expandSegment(ngModule, group, routes, newSegments, outlet, false);
}));
}
private expandRegularSegmentAgainstRouteUsingRedirect(
ngModule: NgModuleRef<any>, segmentGroup: UrlSegmentGroup, routes: Route[], route: Route,
segments: UrlSegment[], outlet: string): Observable<UrlSegmentGroup> {
const {matched, consumedSegments, lastChild, positionalParamSegments} =
match(segmentGroup, route, segments);
if (!matched) return noMatch(segmentGroup);
const newTree = this.applyRedirectCommands(
consumedSegments, route.redirectTo !, <any>positionalParamSegments);
if (route.redirectTo !.startsWith('/')) {
return absoluteRedirect(newTree);
}
return this.lineralizeSegments(route, newTree).pipe(mergeMap((newSegments: UrlSegment[]) => {
return this.expandSegment(
ngModule, segmentGroup, routes, newSegments.concat(segments.slice(lastChild)), outlet,
false);
}));
}
private matchSegmentAgainstRoute(
ngModule: NgModuleRef<any>, rawSegmentGroup: UrlSegmentGroup, route: Route,
segments: UrlSegment[]): Observable<UrlSegmentGroup> {
if (route.path === '**') {
if (route.loadChildren) {
return this.configLoader.load(ngModule.injector, route)
.pipe(map((cfg: LoadedRouterConfig) => {
route._loadedConfig = cfg;
return new UrlSegmentGroup(segments, {});
}));
}
return of (new UrlSegmentGroup(segments, {}));
}
const {matched, consumedSegments, lastChild} = match(rawSegmentGroup, route, segments);
if (!matched) return noMatch(rawSegmentGroup);
const rawSlicedSegments = segments.slice(lastChild);
const childConfig$ = this.getChildConfig(ngModule, route);
return childConfig$.pipe(mergeMap((routerConfig: LoadedRouterConfig) => {
const childModule = routerConfig.module;
const childConfig = routerConfig.routes;
const {segmentGroup, slicedSegments} =
split(rawSegmentGroup, consumedSegments, rawSlicedSegments, childConfig);
if (slicedSegments.length === 0 && segmentGroup.hasChildren()) {
const expanded$ = this.expandChildren(childModule, childConfig, segmentGroup);
return expanded$.pipe(
map((children: any) => new UrlSegmentGroup(consumedSegments, children)));
}
if (childConfig.length === 0 && slicedSegments.length === 0) {
return of (new UrlSegmentGroup(consumedSegments, {}));
}
const expanded$ = this.expandSegment(
childModule, segmentGroup, childConfig, slicedSegments, PRIMARY_OUTLET, true);
return expanded$.pipe(
map((cs: UrlSegmentGroup) =>
new UrlSegmentGroup(consumedSegments.concat(cs.segments), cs.children)));
}));
}
private getChildConfig(ngModule: NgModuleRef<any>, route: Route): Observable<LoadedRouterConfig> {
if (route.children) {
// The children belong to the same module
return of (new LoadedRouterConfig(route.children, ngModule));
}
if (route.loadChildren) {
// lazy children belong to the loaded module
if (route._loadedConfig !== undefined) {
return of (route._loadedConfig);
}
return runCanLoadGuard(ngModule.injector, route).pipe(mergeMap((shouldLoad: boolean) => {
if (shouldLoad) {
return this.configLoader.load(ngModule.injector, route)
.pipe(map((cfg: LoadedRouterConfig) => {
route._loadedConfig = cfg;
return cfg;
}));
}
return canLoadFails(route);
}));
}
return of (new LoadedRouterConfig([], ngModule));
}
private lineralizeSegments(route: Route, urlTree: UrlTree): Observable<UrlSegment[]> {
let res: UrlSegment[] = [];
let c = urlTree.root;
while (true) {
res = res.concat(c.segments);
if (c.numberOfChildren === 0) {
return of (res);
}
if (c.numberOfChildren > 1 || !c.children[PRIMARY_OUTLET]) {
return namedOutletsRedirect(route.redirectTo !);
}
c = c.children[PRIMARY_OUTLET];
}
}
private applyRedirectCommands(
segments: UrlSegment[], redirectTo: string, posParams: {[k: string]: UrlSegment}): UrlTree {
return this.applyRedirectCreatreUrlTree(
redirectTo, this.urlSerializer.parse(redirectTo), segments, posParams);
}
private applyRedirectCreatreUrlTree(
redirectTo: string, urlTree: UrlTree, segments: UrlSegment[],
posParams: {[k: string]: UrlSegment}): UrlTree {
const newRoot = this.createSegmentGroup(redirectTo, urlTree.root, segments, posParams);
return new UrlTree(
newRoot, this.createQueryParams(urlTree.queryParams, this.urlTree.queryParams),
urlTree.fragment);
}
private createQueryParams(redirectToParams: Params, actualParams: Params): Params {
const res: Params = {};
forEach(redirectToParams, (v: any, k: string) => {
const copySourceValue = typeof v === 'string' && v.startsWith(':');
if (copySourceValue) {
const sourceName = v.substring(1);
res[k] = actualParams[sourceName];
} else {
res[k] = v;
}
});
return res;
}
private createSegmentGroup(
redirectTo: string, group: UrlSegmentGroup, segments: UrlSegment[],
posParams: {[k: string]: UrlSegment}): UrlSegmentGroup {
const updatedSegments = this.createSegments(redirectTo, group.segments, segments, posParams);
let children: {[n: string]: UrlSegmentGroup} = {};
forEach(group.children, (child: UrlSegmentGroup, name: string) => {
children[name] = this.createSegmentGroup(redirectTo, child, segments, posParams);
});
return new UrlSegmentGroup(updatedSegments, children);
}
private createSegments(
redirectTo: string, redirectToSegments: UrlSegment[], actualSegments: UrlSegment[],
posParams: {[k: string]: UrlSegment}): UrlSegment[] {
return redirectToSegments.map(
s => s.path.startsWith(':') ? this.findPosParam(redirectTo, s, posParams) :
this.findOrReturn(s, actualSegments));
}
private findPosParam(
redirectTo: string, redirectToUrlSegment: UrlSegment,
posParams: {[k: string]: UrlSegment}): UrlSegment {
const pos = posParams[redirectToUrlSegment.path.substring(1)];
if (!pos)
throw new Error(
`Cannot redirect to '${redirectTo}'. Cannot find '${redirectToUrlSegment.path}'.`);
return pos;
}
private findOrReturn(redirectToUrlSegment: UrlSegment, actualSegments: UrlSegment[]): UrlSegment {
let idx = 0;
for (const s of actualSegments) {
if (s.path === redirectToUrlSegment.path) {
actualSegments.splice(idx);
return s;
}
idx++;
}
return redirectToUrlSegment;
}
}
function runCanLoadGuard(moduleInjector: Injector, route: Route): Observable<boolean> {
const canLoad = route.canLoad;
if (!canLoad || canLoad.length === 0) return of (true);
const obs = from(canLoad).pipe(map((injectionToken: any) => {
const guard = moduleInjector.get(injectionToken);
return wrapIntoObservable(guard.canLoad ? guard.canLoad(route) : guard(route));
}));
return andObservables(obs);
}
function match(segmentGroup: UrlSegmentGroup, route: Route, segments: UrlSegment[]): {
matched: boolean,
consumedSegments: UrlSegment[],
lastChild: number,
positionalParamSegments: {[k: string]: UrlSegment}
} {
if (route.path === '') {
if ((route.pathMatch === 'full') && (segmentGroup.hasChildren() || segments.length > 0)) {
return {matched: false, consumedSegments: [], lastChild: 0, positionalParamSegments: {}};
}
return {matched: true, consumedSegments: [], lastChild: 0, positionalParamSegments: {}};
}
const matcher = route.matcher || defaultUrlMatcher;
const res = matcher(segments, segmentGroup, route);
if (!res) {
return {
matched: false,
consumedSegments: <any[]>[],
lastChild: 0,
positionalParamSegments: {},
};
}
return {
matched: true,
consumedSegments: res.consumed !,
lastChild: res.consumed.length !,
positionalParamSegments: res.posParams !,
};
}
function split(
segmentGroup: UrlSegmentGroup, consumedSegments: UrlSegment[], slicedSegments: UrlSegment[],
config: Route[]) {
if (slicedSegments.length > 0 &&
containsEmptyPathRedirectsWithNamedOutlets(segmentGroup, slicedSegments, config)) {
const s = new UrlSegmentGroup(
consumedSegments, createChildrenForEmptySegments(
config, new UrlSegmentGroup(slicedSegments, segmentGroup.children)));
return {segmentGroup: mergeTrivialChildren(s), slicedSegments: []};
}
if (slicedSegments.length === 0 &&
containsEmptyPathRedirects(segmentGroup, slicedSegments, config)) {
const s = new UrlSegmentGroup(
segmentGroup.segments, addEmptySegmentsToChildrenIfNeeded(
segmentGroup, slicedSegments, config, segmentGroup.children));
return {segmentGroup: mergeTrivialChildren(s), slicedSegments};
}
return {segmentGroup, slicedSegments};
}
function mergeTrivialChildren(s: UrlSegmentGroup): UrlSegmentGroup {
if (s.numberOfChildren === 1 && s.children[PRIMARY_OUTLET]) {
const c = s.children[PRIMARY_OUTLET];
return new UrlSegmentGroup(s.segments.concat(c.segments), c.children);
}
return s;
}
function addEmptySegmentsToChildrenIfNeeded(
segmentGroup: UrlSegmentGroup, slicedSegments: UrlSegment[], routes: Route[],
children: {[name: string]: UrlSegmentGroup}): {[name: string]: UrlSegmentGroup} {
const res: {[name: string]: UrlSegmentGroup} = {};
for (const r of routes) {
if (isEmptyPathRedirect(segmentGroup, slicedSegments, r) && !children[getOutlet(r)]) {
res[getOutlet(r)] = new UrlSegmentGroup([], {});
}
}
return {...children, ...res};
}
function createChildrenForEmptySegments(
routes: Route[], primarySegmentGroup: UrlSegmentGroup): {[name: string]: UrlSegmentGroup} {
const res: {[name: string]: UrlSegmentGroup} = {};
res[PRIMARY_OUTLET] = primarySegmentGroup;
for (const r of routes) {
if (r.path === '' && getOutlet(r) !== PRIMARY_OUTLET) {
res[getOutlet(r)] = new UrlSegmentGroup([], {});
}
}
return res;
}
function containsEmptyPathRedirectsWithNamedOutlets(
segmentGroup: UrlSegmentGroup, segments: UrlSegment[], routes: Route[]): boolean {
return routes.some(
r => isEmptyPathRedirect(segmentGroup, segments, r) && getOutlet(r) !== PRIMARY_OUTLET);
}
function containsEmptyPathRedirects(
segmentGroup: UrlSegmentGroup, segments: UrlSegment[], routes: Route[]): boolean {
return routes.some(r => isEmptyPathRedirect(segmentGroup, segments, r));
}
function isEmptyPathRedirect(
segmentGroup: UrlSegmentGroup, segments: UrlSegment[], r: Route): boolean {
if ((segmentGroup.hasChildren() || segments.length > 0) && r.pathMatch === 'full') {
return false;
}
return r.path === '' && r.redirectTo !== undefined;
}
function getOutlet(route: Route): string {
return route.outlet || PRIMARY_OUTLET;
}