url_tree.ts
/**
* @license
* Copyright Google LLC 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 {convertToParamMap, ParamMap, Params, PRIMARY_OUTLET} from './shared';
import {equalArraysOrString, forEach, shallowEqual} from './utils/collection';
export function createEmptyUrlTree() {
return new UrlTree(new UrlSegmentGroup([], {}), {}, null);
}
/**
* A set of options which specify how to determine if a `UrlTree` is active, given the `UrlTree`
* for the current router state.
*
* @publicApi
* @see Router.isActive
*/
export interface IsActiveMatchOptions {
/**
* Defines the strategy for comparing the matrix parameters of two `UrlTree`s.
*
* The matrix parameter matching is dependent on the strategy for matching the
* segments. That is, if the `paths` option is set to `'subset'`, only
* the matrix parameters of the matching segments will be compared.
*
* - `'exact'`: Requires that matching segments also have exact matrix parameter
* matches.
* - `'subset'`: The matching segments in the router's active `UrlTree` may contain
* extra matrix parameters, but those that exist in the `UrlTree` in question must match.
* - `'ignored'`: When comparing `UrlTree`s, matrix params will be ignored.
*/
matrixParams: 'exact'|'subset'|'ignored';
/**
* Defines the strategy for comparing the query parameters of two `UrlTree`s.
*
* - `'exact'`: the query parameters must match exactly.
* - `'subset'`: the active `UrlTree` may contain extra parameters,
* but must match the key and value of any that exist in the `UrlTree` in question.
* - `'ignored'`: When comparing `UrlTree`s, query params will be ignored.
*/
queryParams: 'exact'|'subset'|'ignored';
/**
* Defines the strategy for comparing the `UrlSegment`s of the `UrlTree`s.
*
* - `'exact'`: all segments in each `UrlTree` must match.
* - `'subset'`: a `UrlTree` will be determined to be active if it
* is a subtree of the active route. That is, the active route may contain extra
* segments, but must at least have all the segements of the `UrlTree` in question.
*/
paths: 'exact'|'subset';
/**
* - 'exact'`: indicates that the `UrlTree` fragments must be equal.
* - `'ignored'`: the fragments will not be compared when determining if a
* `UrlTree` is active.
*/
fragment: 'exact'|'ignored';
}
type ParamMatchOptions = 'exact'|'subset'|'ignored';
type PathCompareFn =
(container: UrlSegmentGroup, containee: UrlSegmentGroup, matrixParams: ParamMatchOptions) =>
boolean;
type ParamCompareFn = (container: Params, containee: Params) => boolean;
const pathCompareMap: Record<IsActiveMatchOptions['paths'], PathCompareFn> = {
'exact': equalSegmentGroups,
'subset': containsSegmentGroup,
};
const paramCompareMap: Record<ParamMatchOptions, ParamCompareFn> = {
'exact': equalParams,
'subset': containsParams,
'ignored': () => true,
};
export function containsTree(
container: UrlTree, containee: UrlTree, options: IsActiveMatchOptions): boolean {
return pathCompareMap[options.paths](container.root, containee.root, options.matrixParams) &&
paramCompareMap[options.queryParams](container.queryParams, containee.queryParams) &&
!(options.fragment === 'exact' && container.fragment !== containee.fragment);
}
function equalParams(container: Params, containee: Params): boolean {
// TODO: This does not handle array params correctly.
return shallowEqual(container, containee);
}
function equalSegmentGroups(
container: UrlSegmentGroup, containee: UrlSegmentGroup,
matrixParams: ParamMatchOptions): boolean {
if (!equalPath(container.segments, containee.segments)) return false;
if (!matrixParamsMatch(container.segments, containee.segments, matrixParams)) {
return false;
}
if (container.numberOfChildren !== containee.numberOfChildren) return false;
for (const c in containee.children) {
if (!container.children[c]) return false;
if (!equalSegmentGroups(container.children[c], containee.children[c], matrixParams))
return false;
}
return true;
}
function containsParams(container: Params, containee: Params): boolean {
return Object.keys(containee).length <= Object.keys(container).length &&
Object.keys(containee).every(key => equalArraysOrString(container[key], containee[key]));
}
function containsSegmentGroup(
container: UrlSegmentGroup, containee: UrlSegmentGroup,
matrixParams: ParamMatchOptions): boolean {
return containsSegmentGroupHelper(container, containee, containee.segments, matrixParams);
}
function containsSegmentGroupHelper(
container: UrlSegmentGroup, containee: UrlSegmentGroup, containeePaths: UrlSegment[],
matrixParams: ParamMatchOptions): boolean {
if (container.segments.length > containeePaths.length) {
const current = container.segments.slice(0, containeePaths.length);
if (!equalPath(current, containeePaths)) return false;
if (containee.hasChildren()) return false;
if (!matrixParamsMatch(current, containeePaths, matrixParams)) return false;
return true;
} else if (container.segments.length === containeePaths.length) {
if (!equalPath(container.segments, containeePaths)) return false;
if (!matrixParamsMatch(container.segments, containeePaths, matrixParams)) return false;
for (const c in containee.children) {
if (!container.children[c]) return false;
if (!containsSegmentGroup(container.children[c], containee.children[c], matrixParams)) {
return false;
}
}
return true;
} else {
const current = containeePaths.slice(0, container.segments.length);
const next = containeePaths.slice(container.segments.length);
if (!equalPath(container.segments, current)) return false;
if (!matrixParamsMatch(container.segments, current, matrixParams)) return false;
if (!container.children[PRIMARY_OUTLET]) return false;
return containsSegmentGroupHelper(
container.children[PRIMARY_OUTLET], containee, next, matrixParams);
}
}
function matrixParamsMatch(
containerPaths: UrlSegment[], containeePaths: UrlSegment[], options: ParamMatchOptions) {
return containeePaths.every((containeeSegment, i) => {
return paramCompareMap[options](containerPaths[i].parameters, containeeSegment.parameters);
});
}
/**
* @description
*
* Represents the parsed URL.
*
* Since a router state is a tree, and the URL is nothing but a serialized state, the URL is a
* serialized tree.
* UrlTree is a data structure that provides a lot of affordances in dealing with URLs
*
* @usageNotes
* ### Example
*
* ```
* @Component({templateUrl:'template.html'})
* class MyComponent {
* constructor(router: Router) {
* const tree: UrlTree =
* router.parseUrl('/team/33/(user/victor//support:help)?debug=true#fragment');
* const f = tree.fragment; // return 'fragment'
* const q = tree.queryParams; // returns {debug: 'true'}
* const g: UrlSegmentGroup = tree.root.children[PRIMARY_OUTLET];
* const s: UrlSegment[] = g.segments; // returns 2 segments 'team' and '33'
* g.children[PRIMARY_OUTLET].segments; // returns 2 segments 'user' and 'victor'
* g.children['support'].segments; // return 1 segment 'help'
* }
* }
* ```
*
* @publicApi
*/
export class UrlTree {
/** @internal */
// TODO(issue/24571): remove '!'.
_queryParamMap!: ParamMap;
/** @internal */
constructor(
/** The root segment group of the URL tree */
public root: UrlSegmentGroup,
/** The query params of the URL */
public queryParams: Params,
/** The fragment of the URL */
public fragment: string|null) {}
get queryParamMap(): ParamMap {
if (!this._queryParamMap) {
this._queryParamMap = convertToParamMap(this.queryParams);
}
return this._queryParamMap;
}
/** @docsNotRequired */
toString(): string {
return DEFAULT_SERIALIZER.serialize(this);
}
}
/**
* @description
*
* Represents the parsed URL segment group.
*
* See `UrlTree` for more information.
*
* @publicApi
*/
export class UrlSegmentGroup {
/** @internal */
_sourceSegment?: UrlSegmentGroup;
/** @internal */
_segmentIndexShift?: number;
/** The parent node in the url tree */
parent: UrlSegmentGroup|null = null;
constructor(
/** The URL segments of this group. See `UrlSegment` for more information */
public segments: UrlSegment[],
/** The list of children of this group */
public children: {[key: string]: UrlSegmentGroup}) {
forEach(children, (v: any, k: any) => v.parent = this);
}
/** Whether the segment has child segments */
hasChildren(): boolean {
return this.numberOfChildren > 0;
}
/** Number of child segments */
get numberOfChildren(): number {
return Object.keys(this.children).length;
}
/** @docsNotRequired */
toString(): string {
return serializePaths(this);
}
}
/**
* @description
*
* Represents a single URL segment.
*
* A UrlSegment is a part of a URL between the two slashes. It contains a path and the matrix
* parameters associated with the segment.
*
* @usageNotes
* ### Example
*
* ```
* @Component({templateUrl:'template.html'})
* class MyComponent {
* constructor(router: Router) {
* const tree: UrlTree = router.parseUrl('/team;id=33');
* const g: UrlSegmentGroup = tree.root.children[PRIMARY_OUTLET];
* const s: UrlSegment[] = g.segments;
* s[0].path; // returns 'team'
* s[0].parameters; // returns {id: 33}
* }
* }
* ```
*
* @publicApi
*/
export class UrlSegment {
/** @internal */
// TODO(issue/24571): remove '!'.
_parameterMap!: ParamMap;
constructor(
/** The path part of a URL segment */
public path: string,
/** The matrix parameters associated with a segment */
public parameters: {[name: string]: string}) {}
get parameterMap(): ParamMap {
if (!this._parameterMap) {
this._parameterMap = convertToParamMap(this.parameters);
}
return this._parameterMap;
}
/** @docsNotRequired */
toString(): string {
return serializePath(this);
}
}
export function equalSegments(as: UrlSegment[], bs: UrlSegment[]): boolean {
return equalPath(as, bs) && as.every((a, i) => shallowEqual(a.parameters, bs[i].parameters));
}
export function equalPath(as: UrlSegment[], bs: UrlSegment[]): boolean {
if (as.length !== bs.length) return false;
return as.every((a, i) => a.path === bs[i].path);
}
export function mapChildrenIntoArray<T>(
segment: UrlSegmentGroup, fn: (v: UrlSegmentGroup, k: string) => T[]): T[] {
let res: T[] = [];
forEach(segment.children, (child: UrlSegmentGroup, childOutlet: string) => {
if (childOutlet === PRIMARY_OUTLET) {
res = res.concat(fn(child, childOutlet));
}
});
forEach(segment.children, (child: UrlSegmentGroup, childOutlet: string) => {
if (childOutlet !== PRIMARY_OUTLET) {
res = res.concat(fn(child, childOutlet));
}
});
return res;
}
/**
* @description
*
* Serializes and deserializes a URL string into a URL tree.
*
* The url serialization strategy is customizable. You can
* make all URLs case insensitive by providing a custom UrlSerializer.
*
* See `DefaultUrlSerializer` for an example of a URL serializer.
*
* @publicApi
*/
export abstract class UrlSerializer {
/** Parse a url into a `UrlTree` */
abstract parse(url: string): UrlTree;
/** Converts a `UrlTree` into a url */
abstract serialize(tree: UrlTree): string;
}
/**
* @description
*
* A default implementation of the `UrlSerializer`.
*
* Example URLs:
*
* ```
* /inbox/33(popup:compose)
* /inbox/33;open=true/messages/44
* ```
*
* DefaultUrlSerializer uses parentheses to serialize secondary segments (e.g., popup:compose), the
* colon syntax to specify the outlet, and the ';parameter=value' syntax (e.g., open=true) to
* specify route specific parameters.
*
* @publicApi
*/
export class DefaultUrlSerializer implements UrlSerializer {
/** Parses a url into a `UrlTree` */
parse(url: string): UrlTree {
const p = new UrlParser(url);
return new UrlTree(p.parseRootSegment(), p.parseQueryParams(), p.parseFragment());
}
/** Converts a `UrlTree` into a url */
serialize(tree: UrlTree): string {
const segment = `/${serializeSegment(tree.root, true)}`;
const query = serializeQueryParams(tree.queryParams);
const fragment =
typeof tree.fragment === `string` ? `#${encodeUriFragment(tree.fragment)}` : '';
return `${segment}${query}${fragment}`;
}
}
const DEFAULT_SERIALIZER = new DefaultUrlSerializer();
export function serializePaths(segment: UrlSegmentGroup): string {
return segment.segments.map(p => serializePath(p)).join('/');
}
function serializeSegment(segment: UrlSegmentGroup, root: boolean): string {
if (!segment.hasChildren()) {
return serializePaths(segment);
}
if (root) {
const primary = segment.children[PRIMARY_OUTLET] ?
serializeSegment(segment.children[PRIMARY_OUTLET], false) :
'';
const children: string[] = [];
forEach(segment.children, (v: UrlSegmentGroup, k: string) => {
if (k !== PRIMARY_OUTLET) {
children.push(`${k}:${serializeSegment(v, false)}`);
}
});
return children.length > 0 ? `${primary}(${children.join('//')})` : primary;
} else {
const children = mapChildrenIntoArray(segment, (v: UrlSegmentGroup, k: string) => {
if (k === PRIMARY_OUTLET) {
return [serializeSegment(segment.children[PRIMARY_OUTLET], false)];
}
return [`${k}:${serializeSegment(v, false)}`];
});
// use no parenthesis if the only child is a primary outlet route
if (Object.keys(segment.children).length === 1 && segment.children[PRIMARY_OUTLET] != null) {
return `${serializePaths(segment)}/${children[0]}`;
}
return `${serializePaths(segment)}/(${children.join('//')})`;
}
}
/**
* Encodes a URI string with the default encoding. This function will only ever be called from
* `encodeUriQuery` or `encodeUriSegment` as it's the base set of encodings to be used. We need
* a custom encoding because encodeURIComponent is too aggressive and encodes stuff that doesn't
* have to be encoded per https://url.spec.whatwg.org.
*/
function encodeUriString(s: string): string {
return encodeURIComponent(s)
.replace(/%40/g, '@')
.replace(/%3A/gi, ':')
.replace(/%24/g, '$')
.replace(/%2C/gi, ',');
}
/**
* This function should be used to encode both keys and values in a query string key/value. In
* the following URL, you need to call encodeUriQuery on "k" and "v":
*
* http://www.site.org/html;mk=mv?k=v#f
*/
export function encodeUriQuery(s: string): string {
return encodeUriString(s).replace(/%3B/gi, ';');
}
/**
* This function should be used to encode a URL fragment. In the following URL, you need to call
* encodeUriFragment on "f":
*
* http://www.site.org/html;mk=mv?k=v#f
*/
export function encodeUriFragment(s: string): string {
return encodeURI(s);
}
/**
* This function should be run on any URI segment as well as the key and value in a key/value
* pair for matrix params. In the following URL, you need to call encodeUriSegment on "html",
* "mk", and "mv":
*
* http://www.site.org/html;mk=mv?k=v#f
*/
export function encodeUriSegment(s: string): string {
return encodeUriString(s).replace(/\(/g, '%28').replace(/\)/g, '%29').replace(/%26/gi, '&');
}
export function decode(s: string): string {
return decodeURIComponent(s);
}
// Query keys/values should have the "+" replaced first, as "+" in a query string is " ".
// decodeURIComponent function will not decode "+" as a space.
export function decodeQuery(s: string): string {
return decode(s.replace(/\+/g, '%20'));
}
export function serializePath(path: UrlSegment): string {
return `${encodeUriSegment(path.path)}${serializeMatrixParams(path.parameters)}`;
}
function serializeMatrixParams(params: {[key: string]: string}): string {
return Object.keys(params)
.map(key => `;${encodeUriSegment(key)}=${encodeUriSegment(params[key])}`)
.join('');
}
function serializeQueryParams(params: {[key: string]: any}): string {
const strParams: string[] =
Object.keys(params)
.map((name) => {
const value = params[name];
return Array.isArray(value) ?
value.map(v => `${encodeUriQuery(name)}=${encodeUriQuery(v)}`).join('&') :
`${encodeUriQuery(name)}=${encodeUriQuery(value)}`;
})
.filter(s => !!s);
return strParams.length ? `?${strParams.join('&')}` : '';
}
const SEGMENT_RE = /^[^\/()?;=#]+/;
function matchSegments(str: string): string {
const match = str.match(SEGMENT_RE);
return match ? match[0] : '';
}
const QUERY_PARAM_RE = /^[^=?&#]+/;
// Return the name of the query param at the start of the string or an empty string
function matchQueryParams(str: string): string {
const match = str.match(QUERY_PARAM_RE);
return match ? match[0] : '';
}
const QUERY_PARAM_VALUE_RE = /^[^&#]+/;
// Return the value of the query param at the start of the string or an empty string
function matchUrlQueryParamValue(str: string): string {
const match = str.match(QUERY_PARAM_VALUE_RE);
return match ? match[0] : '';
}
class UrlParser {
private remaining: string;
constructor(private url: string) {
this.remaining = url;
}
parseRootSegment(): UrlSegmentGroup {
this.consumeOptional('/');
if (this.remaining === '' || this.peekStartsWith('?') || this.peekStartsWith('#')) {
return new UrlSegmentGroup([], {});
}
// The root segment group never has segments
return new UrlSegmentGroup([], this.parseChildren());
}
parseQueryParams(): Params {
const params: Params = {};
if (this.consumeOptional('?')) {
do {
this.parseQueryParam(params);
} while (this.consumeOptional('&'));
}
return params;
}
parseFragment(): string|null {
return this.consumeOptional('#') ? decodeURIComponent(this.remaining) : null;
}
private parseChildren(): {[outlet: string]: UrlSegmentGroup} {
if (this.remaining === '') {
return {};
}
this.consumeOptional('/');
const segments: UrlSegment[] = [];
if (!this.peekStartsWith('(')) {
segments.push(this.parseSegment());
}
while (this.peekStartsWith('/') && !this.peekStartsWith('//') && !this.peekStartsWith('/(')) {
this.capture('/');
segments.push(this.parseSegment());
}
let children: {[outlet: string]: UrlSegmentGroup} = {};
if (this.peekStartsWith('/(')) {
this.capture('/');
children = this.parseParens(true);
}
let res: {[outlet: string]: UrlSegmentGroup} = {};
if (this.peekStartsWith('(')) {
res = this.parseParens(false);
}
if (segments.length > 0 || Object.keys(children).length > 0) {
res[PRIMARY_OUTLET] = new UrlSegmentGroup(segments, children);
}
return res;
}
// parse a segment with its matrix parameters
// ie `name;k1=v1;k2`
private parseSegment(): UrlSegment {
const path = matchSegments(this.remaining);
if (path === '' && this.peekStartsWith(';')) {
throw new Error(`Empty path url segment cannot have parameters: '${this.remaining}'.`);
}
this.capture(path);
return new UrlSegment(decode(path), this.parseMatrixParams());
}
private parseMatrixParams(): {[key: string]: string} {
const params: {[key: string]: string} = {};
while (this.consumeOptional(';')) {
this.parseParam(params);
}
return params;
}
private parseParam(params: {[key: string]: string}): void {
const key = matchSegments(this.remaining);
if (!key) {
return;
}
this.capture(key);
let value: any = '';
if (this.consumeOptional('=')) {
const valueMatch = matchSegments(this.remaining);
if (valueMatch) {
value = valueMatch;
this.capture(value);
}
}
params[decode(key)] = decode(value);
}
// Parse a single query parameter `name[=value]`
private parseQueryParam(params: Params): void {
const key = matchQueryParams(this.remaining);
if (!key) {
return;
}
this.capture(key);
let value: any = '';
if (this.consumeOptional('=')) {
const valueMatch = matchUrlQueryParamValue(this.remaining);
if (valueMatch) {
value = valueMatch;
this.capture(value);
}
}
const decodedKey = decodeQuery(key);
const decodedVal = decodeQuery(value);
if (params.hasOwnProperty(decodedKey)) {
// Append to existing values
let currentVal = params[decodedKey];
if (!Array.isArray(currentVal)) {
currentVal = [currentVal];
params[decodedKey] = currentVal;
}
currentVal.push(decodedVal);
} else {
// Create a new value
params[decodedKey] = decodedVal;
}
}
// parse `(a/b//outlet_name:c/d)`
private parseParens(allowPrimary: boolean): {[outlet: string]: UrlSegmentGroup} {
const segments: {[key: string]: UrlSegmentGroup} = {};
this.capture('(');
while (!this.consumeOptional(')') && this.remaining.length > 0) {
const path = matchSegments(this.remaining);
const next = this.remaining[path.length];
// if is is not one of these characters, then the segment was unescaped
// or the group was not closed
if (next !== '/' && next !== ')' && next !== ';') {
throw new Error(`Cannot parse url '${this.url}'`);
}
let outletName: string = undefined!;
if (path.indexOf(':') > -1) {
outletName = path.substr(0, path.indexOf(':'));
this.capture(outletName);
this.capture(':');
} else if (allowPrimary) {
outletName = PRIMARY_OUTLET;
}
const children = this.parseChildren();
segments[outletName] = Object.keys(children).length === 1 ? children[PRIMARY_OUTLET] :
new UrlSegmentGroup([], children);
this.consumeOptional('//');
}
return segments;
}
private peekStartsWith(str: string): boolean {
return this.remaining.startsWith(str);
}
// Consumes the prefix when it is present and returns whether it has been consumed
private consumeOptional(str: string): boolean {
if (this.peekStartsWith(str)) {
this.remaining = this.remaining.substring(str.length);
return true;
}
return false;
}
private capture(str: string): void {
if (!this.consumeOptional(str)) {
throw new Error(`Expected "${str}".`);
}
}
}
