@remix-run/headers
Version:
A toolkit for working with HTTP headers in JavaScript
750 lines (749 loc) • 27.1 kB
JavaScript
import { Accept } from "./accept.js";
import { AcceptEncoding } from "./accept-encoding.js";
import { AcceptLanguage } from "./accept-language.js";
import { CacheControl } from "./cache-control.js";
import { ContentDisposition } from "./content-disposition.js";
import { ContentRange } from "./content-range.js";
import { ContentType } from "./content-type.js";
import { Cookie } from "./cookie.js";
import { canonicalHeaderName } from "./header-names.js";
import {} from "./header-value.js";
import { IfMatch } from "./if-match.js";
import { IfNoneMatch } from "./if-none-match.js";
import { IfRange } from "./if-range.js";
import { Range } from "./range.js";
import { SetCookie } from "./set-cookie.js";
import { Vary } from "./vary.js";
import { isIterable, quoteEtag } from "./utils.js";
const CRLF = '\r\n';
const AcceptKey = 'accept';
const AcceptEncodingKey = 'accept-encoding';
const AcceptLanguageKey = 'accept-language';
const AcceptRangesKey = 'accept-ranges';
const AgeKey = 'age';
const AllowKey = 'allow';
const CacheControlKey = 'cache-control';
const ConnectionKey = 'connection';
const ContentDispositionKey = 'content-disposition';
const ContentEncodingKey = 'content-encoding';
const ContentLanguageKey = 'content-language';
const ContentLengthKey = 'content-length';
const ContentRangeKey = 'content-range';
const ContentTypeKey = 'content-type';
const CookieKey = 'cookie';
const DateKey = 'date';
const ETagKey = 'etag';
const ExpiresKey = 'expires';
const HostKey = 'host';
const IfMatchKey = 'if-match';
const IfModifiedSinceKey = 'if-modified-since';
const IfNoneMatchKey = 'if-none-match';
const IfRangeKey = 'if-range';
const IfUnmodifiedSinceKey = 'if-unmodified-since';
const LastModifiedKey = 'last-modified';
const LocationKey = 'location';
const RangeKey = 'range';
const RefererKey = 'referer';
const SetCookieKey = 'set-cookie';
const VaryKey = 'vary';
/**
* An enhanced JavaScript `Headers` interface with type-safe access.
*
* [API Reference](https://github.com/remix-run/remix/tree/main/packages/headers)
*
* [MDN `Headers` Base Class Reference](https://developer.mozilla.org/en-US/docs/Web/API/Headers)
*/
export class SuperHeaders extends Headers {
#map;
#setCookies = [];
/**
* @param init A string, iterable, object, or `Headers` instance to initialize with
*/
constructor(init) {
super();
this.#map = new Map();
if (init) {
if (typeof init === 'string') {
let lines = init.split(CRLF);
for (let line of lines) {
let match = line.match(/^([^:]+):(.*)/);
if (match) {
this.append(match[1].trim(), match[2].trim());
}
}
}
else if (isIterable(init)) {
for (let [name, value] of init) {
this.append(name, value);
}
}
else if (typeof init === 'object') {
for (let name of Object.getOwnPropertyNames(init)) {
let value = init[name];
let descriptor = Object.getOwnPropertyDescriptor(SuperHeaders.prototype, name);
if (descriptor?.set) {
descriptor.set.call(this, value);
}
else {
this.set(name, value.toString());
}
}
}
}
}
/**
* Appends a new header value to the existing set of values for a header,
* or adds the header if it does not already exist.
*
* [MDN Reference](https://developer.mozilla.org/en-US/docs/Web/API/Headers/append)
*
* @param name The name of the header to append to
* @param value The value to append
*/
append(name, value) {
let key = name.toLowerCase();
if (key === SetCookieKey) {
this.#setCookies.push(value);
}
else {
let existingValue = this.#map.get(key);
this.#map.set(key, existingValue ? `${existingValue}, ${value}` : value);
}
}
/**
* Removes a header.
*
* [MDN Reference](https://developer.mozilla.org/en-US/docs/Web/API/Headers/delete)
*
* @param name The name of the header to delete
*/
delete(name) {
let key = name.toLowerCase();
if (key === SetCookieKey) {
this.#setCookies = [];
}
else {
this.#map.delete(key);
}
}
/**
* Returns a string of all the values for a header, or `null` if the header does not exist.
*
* [MDN Reference](https://developer.mozilla.org/en-US/docs/Web/API/Headers/get)
*
* @param name The name of the header to get
* @return The header value, or `null` if not found
*/
get(name) {
let key = name.toLowerCase();
if (key === SetCookieKey) {
return this.getSetCookie().join(', ');
}
else {
let value = this.#map.get(key);
if (typeof value === 'string') {
return value;
}
else if (value != null) {
let str = value.toString();
return str === '' ? null : str;
}
else {
return null;
}
}
}
/**
* Returns an array of all values associated with the `Set-Cookie` header. This is
* useful when building headers for a HTTP response since multiple `Set-Cookie` headers
* must be sent on separate lines.
*
* [MDN Reference](https://developer.mozilla.org/en-US/docs/Web/API/Headers/getSetCookie)
*
* @return An array of `Set-Cookie` header values
*/
getSetCookie() {
return this.#setCookies.map((v) => (typeof v === 'string' ? v : v.toString()));
}
/**
* Returns `true` if the header is present in the list of headers.
*
* [MDN Reference](https://developer.mozilla.org/en-US/docs/Web/API/Headers/has)
*
* @param name The name of the header to check
* @return `true` if the header is present, `false` otherwise
*/
has(name) {
let key = name.toLowerCase();
return key === SetCookieKey ? this.#setCookies.length > 0 : this.get(key) != null;
}
/**
* Sets a new value for the given header. If the header already exists, the new value
* will replace the existing value.
*
* [MDN Reference](https://developer.mozilla.org/en-US/docs/Web/API/Headers/set)
*
* @param name The name of the header to set
* @param value The value to set
*/
set(name, value) {
let key = name.toLowerCase();
if (key === SetCookieKey) {
this.#setCookies = [value];
}
else {
this.#map.set(key, value);
}
}
/**
* Returns an iterator of all header keys (lowercase).
*
* [MDN Reference](https://developer.mozilla.org/en-US/docs/Web/API/Headers/keys)
*
* @return An iterator of header keys
*/
*keys() {
for (let [key] of this)
yield key;
}
/**
* Returns an iterator of all header values.
*
* [MDN Reference](https://developer.mozilla.org/en-US/docs/Web/API/Headers/values)
*
* @return An iterator of header values
*/
*values() {
for (let [, value] of this)
yield value;
}
/**
* Returns an iterator of all header key/value pairs.
*
* [MDN Reference](https://developer.mozilla.org/en-US/docs/Web/API/Headers/entries)
*
* @return An iterator of `[key, value]` tuples
*/
*entries() {
for (let [key] of this.#map) {
let str = this.get(key);
if (str)
yield [key, str];
}
for (let value of this.getSetCookie()) {
yield [SetCookieKey, value];
}
}
[Symbol.iterator]() {
return this.entries();
}
/**
* Invokes the `callback` for each header key/value pair.
*
* [MDN Reference](https://developer.mozilla.org/en-US/docs/Web/API/Headers/forEach)
*
* @param callback The function to call for each pair
* @param thisArg The value to use as `this` when calling the callback
*/
forEach(callback, thisArg) {
for (let [key, value] of this) {
callback.call(thisArg, value, key, this);
}
}
/**
* Returns a string representation of the headers suitable for use in a HTTP message.
*
* @return The headers formatted for HTTP
*/
toString() {
let lines = [];
for (let [key, value] of this) {
lines.push(`${canonicalHeaderName(key)}: ${value}`);
}
return lines.join(CRLF);
}
// Header-specific getters and setters
/**
* The `Accept` header is used by clients to indicate the media types that are acceptable
* in the response.
*
* [MDN `Accept` Reference](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Accept)
*
* [HTTP/1.1 Specification](https://datatracker.ietf.org/doc/html/rfc7231#section-5.3.2)
*/
get accept() {
return this.#getHeaderValue(AcceptKey, Accept);
}
set accept(value) {
this.#setHeaderValue(AcceptKey, Accept, value);
}
/**
* The `Accept-Encoding` header contains information about the content encodings that the client
* is willing to accept in the response.
*
* [MDN `Accept-Encoding` Reference](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Accept-Encoding)
*
* [HTTP/1.1 Specification](https://datatracker.ietf.org/doc/html/rfc7231#section-5.3.4)
*/
get acceptEncoding() {
return this.#getHeaderValue(AcceptEncodingKey, AcceptEncoding);
}
set acceptEncoding(value) {
this.#setHeaderValue(AcceptEncodingKey, AcceptEncoding, value);
}
/**
* The `Accept-Language` header contains information about preferred natural language for the
* response.
*
* [MDN `Accept-Language` Reference](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Accept-Language)
*
* [HTTP/1.1 Specification](https://datatracker.ietf.org/doc/html/rfc7231#section-5.3.5)
*/
get acceptLanguage() {
return this.#getHeaderValue(AcceptLanguageKey, AcceptLanguage);
}
set acceptLanguage(value) {
this.#setHeaderValue(AcceptLanguageKey, AcceptLanguage, value);
}
/**
* The `Accept-Ranges` header indicates the server's acceptance of range requests.
*
* [MDN `Accept-Ranges` Reference](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Accept-Ranges)
*
* [HTTP/1.1 Specification](https://datatracker.ietf.org/doc/html/rfc7233#section-2.3)
*/
get acceptRanges() {
return this.#getStringValue(AcceptRangesKey);
}
set acceptRanges(value) {
this.#setStringValue(AcceptRangesKey, value);
}
/**
* The `Age` header contains the time in seconds an object was in a proxy cache.
*
* [MDN `Age` Reference](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Age)
*
* [HTTP/1.1 Specification](https://datatracker.ietf.org/doc/html/rfc7234#section-5.1)
*/
get age() {
return this.#getNumberValue(AgeKey);
}
set age(value) {
this.#setNumberValue(AgeKey, value);
}
/**
* The `Allow` header lists the HTTP methods that are supported by the resource.
*
* [MDN `Allow` Reference](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Allow)
*
* [HTTP/1.1 Specification](https://httpwg.org/specs/rfc9110.html#field.allow)
*/
get allow() {
return this.#getStringValue(AllowKey);
}
set allow(value) {
this.#setStringValue(AllowKey, Array.isArray(value) ? value.join(', ') : value);
}
/**
* The `Cache-Control` header contains directives for caching mechanisms in both requests and responses.
*
* [MDN `Cache-Control` Reference](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Cache-Control)
*
* [HTTP/1.1 Specification](https://datatracker.ietf.org/doc/html/rfc7234#section-5.2)
*/
get cacheControl() {
return this.#getHeaderValue(CacheControlKey, CacheControl);
}
set cacheControl(value) {
this.#setHeaderValue(CacheControlKey, CacheControl, value);
}
/**
* The `Connection` header controls whether the network connection stays open after the current
* transaction finishes.
*
* [MDN `Connection` Reference](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Connection)
*
* [HTTP/1.1 Specification](https://datatracker.ietf.org/doc/html/rfc7230#section-6.1)
*/
get connection() {
return this.#getStringValue(ConnectionKey);
}
set connection(value) {
this.#setStringValue(ConnectionKey, value);
}
/**
* The `Content-Disposition` header is a response-type header that describes how the payload is displayed.
*
* [MDN `Content-Disposition` Reference](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Disposition)
*
* [RFC 6266](https://datatracker.ietf.org/doc/html/rfc6266)
*/
get contentDisposition() {
return this.#getHeaderValue(ContentDispositionKey, ContentDisposition);
}
set contentDisposition(value) {
this.#setHeaderValue(ContentDispositionKey, ContentDisposition, value);
}
/**
* The `Content-Encoding` header specifies the encoding of the resource.
*
* Note: If multiple encodings have been used, this value may be a comma-separated list. However, most often this
* header will only contain a single value.
*
* [MDN `Content-Encoding` Reference](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Encoding)
*
* [HTTP/1.1 Specification](https://httpwg.org/specs/rfc9110.html#field.content-encoding)
*/
get contentEncoding() {
return this.#getStringValue(ContentEncodingKey);
}
set contentEncoding(value) {
this.#setStringValue(ContentEncodingKey, Array.isArray(value) ? value.join(', ') : value);
}
/**
* The `Content-Language` header describes the natural language(s) of the intended audience for the response content.
*
* Note: If the response content is intended for multiple audiences, this value may be a comma-separated list. However,
* most often this header will only contain a single value.
*
* [MDN `Content-Language` Reference](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Language)
*
* [HTTP/1.1 Specification](https://httpwg.org/specs/rfc9110.html#field.content-language)
*/
get contentLanguage() {
return this.#getStringValue(ContentLanguageKey);
}
set contentLanguage(value) {
this.#setStringValue(ContentLanguageKey, Array.isArray(value) ? value.join(', ') : value);
}
/**
* The `Content-Length` header indicates the size of the entity-body in bytes.
*
* [MDN `Content-Length` Reference](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Length)
*
* [HTTP/1.1 Specification](https://datatracker.ietf.org/doc/html/rfc7230#section-3.3.2)
*/
get contentLength() {
return this.#getNumberValue(ContentLengthKey);
}
set contentLength(value) {
this.#setNumberValue(ContentLengthKey, value);
}
/**
* The `Content-Range` header indicates where the content of a response body
* belongs in relation to a complete resource.
*
* [MDN `Content-Range` Reference](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Range)
*
* [HTTP/1.1 Specification](https://httpwg.org/specs/rfc9110.html#field.content-range)
*/
get contentRange() {
return this.#getHeaderValue(ContentRangeKey, ContentRange);
}
set contentRange(value) {
this.#setHeaderValue(ContentRangeKey, ContentRange, value);
}
/**
* The `Content-Type` header indicates the media type of the resource.
*
* [MDN `Content-Type` Reference](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Type)
*
* [HTTP/1.1 Specification](https://datatracker.ietf.org/doc/html/rfc7231#section-3.1.1.5)
*/
get contentType() {
return this.#getHeaderValue(ContentTypeKey, ContentType);
}
set contentType(value) {
this.#setHeaderValue(ContentTypeKey, ContentType, value);
}
/**
* The `Cookie` request header contains stored HTTP cookies previously sent by the server with
* the `Set-Cookie` header.
*
* [MDN `Cookie` Reference](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Cookie)
*
* [HTTP/1.1 Specification](https://datatracker.ietf.org/doc/html/rfc6265#section-5.4)
*/
get cookie() {
return this.#getHeaderValue(CookieKey, Cookie);
}
set cookie(value) {
this.#setHeaderValue(CookieKey, Cookie, value);
}
/**
* The `Date` header contains the date and time at which the message was sent.
*
* [MDN `Date` Reference](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Date)
*
* [HTTP/1.1 Specification](https://datatracker.ietf.org/doc/html/rfc7231#section-7.1.1.2)
*/
get date() {
return this.#getDateValue(DateKey);
}
set date(value) {
this.#setDateValue(DateKey, value);
}
/**
* The `ETag` header provides a unique identifier for the current version of the resource.
*
* [MDN `ETag` Reference](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/ETag)
*
* [HTTP/1.1 Specification](https://datatracker.ietf.org/doc/html/rfc7232#section-2.3)
*/
get etag() {
return this.#getStringValue(ETagKey);
}
set etag(value) {
this.#setStringValue(ETagKey, typeof value === 'string' ? quoteEtag(value) : value);
}
/**
* The `Expires` header contains the date/time after which the response is considered stale.
*
* [MDN `Expires` Reference](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Expires)
*
* [HTTP/1.1 Specification](https://datatracker.ietf.org/doc/html/rfc7234#section-5.3)
*/
get expires() {
return this.#getDateValue(ExpiresKey);
}
set expires(value) {
this.#setDateValue(ExpiresKey, value);
}
/**
* The `Host` header specifies the domain name of the server and (optionally) the TCP port number.
*
* [MDN `Host` Reference](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Host)
*
* [HTTP/1.1 Specification](https://datatracker.ietf.org/doc/html/rfc7230#section-5.4)
*/
get host() {
return this.#getStringValue(HostKey);
}
set host(value) {
this.#setStringValue(HostKey, value);
}
/**
* The `If-Modified-Since` header makes a request conditional on the last modification date of the
* requested resource.
*
* [MDN `If-Modified-Since` Reference](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/If-Modified-Since)
*
* [HTTP/1.1 Specification](https://datatracker.ietf.org/doc/html/rfc7232#section-3.3)
*/
get ifModifiedSince() {
return this.#getDateValue(IfModifiedSinceKey);
}
set ifModifiedSince(value) {
this.#setDateValue(IfModifiedSinceKey, value);
}
/**
* The `If-Match` header makes a request conditional on the presence of a matching ETag.
*
* [MDN `If-Match` Reference](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/If-Match)
*
* [HTTP/1.1 Specification](https://datatracker.ietf.org/doc/html/rfc7232#section-3.1)
*/
get ifMatch() {
return this.#getHeaderValue(IfMatchKey, IfMatch);
}
set ifMatch(value) {
this.#setHeaderValue(IfMatchKey, IfMatch, value);
}
/**
* The `If-None-Match` header makes a request conditional on the absence of a matching ETag.
*
* [MDN `If-None-Match` Reference](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/If-None-Match)
*
* [HTTP/1.1 Specification](https://datatracker.ietf.org/doc/html/rfc7232#section-3.2)
*/
get ifNoneMatch() {
return this.#getHeaderValue(IfNoneMatchKey, IfNoneMatch);
}
set ifNoneMatch(value) {
this.#setHeaderValue(IfNoneMatchKey, IfNoneMatch, value);
}
/**
* The `If-Range` header makes a range request conditional on the resource state.
* Can contain either an entity tag (ETag) or an HTTP date.
*
* [MDN `If-Range` Reference](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/If-Range)
*
* [HTTP/1.1 Specification](https://datatracker.ietf.org/doc/html/rfc7233#section-3.2)
*/
get ifRange() {
return this.#getHeaderValue(IfRangeKey, IfRange);
}
set ifRange(value) {
this.#setHeaderValue(IfRangeKey, IfRange, value);
}
/**
* The `If-Unmodified-Since` header makes a request conditional on the last modification date of the
* requested resource.
*
* [MDN `If-Unmodified-Since` Reference](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/If-Unmodified-Since)
*
* [HTTP/1.1 Specification](https://datatracker.ietf.org/doc/html/rfc7232#section-3.4)
*/
get ifUnmodifiedSince() {
return this.#getDateValue(IfUnmodifiedSinceKey);
}
set ifUnmodifiedSince(value) {
this.#setDateValue(IfUnmodifiedSinceKey, value);
}
/**
* The `Last-Modified` header contains the date and time at which the resource was last modified.
*
* [MDN `Last-Modified` Reference](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Last-Modified)
*
* [HTTP/1.1 Specification](https://datatracker.ietf.org/doc/html/rfc7232#section-2.2)
*/
get lastModified() {
return this.#getDateValue(LastModifiedKey);
}
set lastModified(value) {
this.#setDateValue(LastModifiedKey, value);
}
/**
* The `Location` header indicates the URL to redirect to.
*
* [MDN `Location` Reference](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Location)
*
* [HTTP/1.1 Specification](https://datatracker.ietf.org/doc/html/rfc7231#section-7.1.2)
*/
get location() {
return this.#getStringValue(LocationKey);
}
set location(value) {
this.#setStringValue(LocationKey, value);
}
/**
* The `Range` header indicates the part of a resource that the client wants to receive.
*
* [MDN `Range` Reference](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Range)
*
* [HTTP/1.1 Specification](https://httpwg.org/specs/rfc9110.html#field.range)
*/
get range() {
return this.#getHeaderValue(RangeKey, Range);
}
set range(value) {
this.#setHeaderValue(RangeKey, Range, value);
}
/**
* The `Referer` header contains the address of the previous web page from which a link to the
* currently requested page was followed.
*
* [MDN `Referer` Reference](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Referer)
*
* [HTTP/1.1 Specification](https://datatracker.ietf.org/doc/html/rfc7231#section-5.5.2)
*/
get referer() {
return this.#getStringValue(RefererKey);
}
set referer(value) {
this.#setStringValue(RefererKey, value);
}
/**
* The `Set-Cookie` header is used to send cookies from the server to the user agent.
*
* [MDN `Set-Cookie` Reference](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Set-Cookie)
*
* [HTTP/1.1 Specification](https://datatracker.ietf.org/doc/html/rfc6265#section-4.1)
*/
get setCookie() {
let setCookies = this.#setCookies;
for (let i = 0; i < setCookies.length; ++i) {
if (typeof setCookies[i] === 'string') {
setCookies[i] = new SetCookie(setCookies[i]);
}
}
return setCookies;
}
set setCookie(value) {
if (value != null) {
this.#setCookies = (Array.isArray(value) ? value : [value]).map((v) => typeof v === 'string' ? v : new SetCookie(v));
}
else {
this.#setCookies = [];
}
}
/**
* The `Vary` header indicates the set of request headers that determine whether
* a cached response can be used rather than requesting a fresh response from the origin server.
*
* Common values include `Accept-Encoding`, `Accept-Language`, `Accept`, `User-Agent`, etc.
*
* [MDN `Vary` Reference](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Vary)
*
* [HTTP/1.1 Specification](https://httpwg.org/specs/rfc9110.html#field.vary)
*/
get vary() {
return this.#getHeaderValue(VaryKey, Vary);
}
set vary(value) {
this.#setHeaderValue(VaryKey, Vary, value);
}
// Helpers
#getHeaderValue(key, ctor) {
let value = this.#map.get(key);
if (value !== undefined) {
if (typeof value === 'string') {
let obj = new ctor(value);
this.#map.set(key, obj); // cache the new object
return obj;
}
else {
return value;
}
}
let obj = new ctor();
this.#map.set(key, obj); // cache the new object
return obj;
}
#setHeaderValue(key, ctor, value) {
if (value != null) {
this.#map.set(key, typeof value === 'string' ? value : new ctor(value));
}
else {
this.#map.delete(key);
}
}
#getDateValue(key) {
let value = this.#map.get(key);
return value === undefined ? null : new Date(value);
}
#setDateValue(key, value) {
if (value != null) {
this.#map.set(key, typeof value === 'string'
? value
: (typeof value === 'number' ? new Date(value) : value).toUTCString());
}
else {
this.#map.delete(key);
}
}
#getNumberValue(key) {
let value = this.#map.get(key);
return value === undefined ? null : parseInt(value, 10);
}
#setNumberValue(key, value) {
if (value != null) {
this.#map.set(key, typeof value === 'string' ? value : value.toString());
}
else {
this.#map.delete(key);
}
}
#getStringValue(key) {
let value = this.#map.get(key);
return value === undefined ? null : value;
}
#setStringValue(key, value) {
if (value != null) {
this.#map.set(key, value);
}
else {
this.#map.delete(key);
}
}
}