SequenceDiagram/bin/server/RequestHandler.js

97 lines
1.9 KiB
JavaScript

function makeCacheControlHeader({
mode = 'public',
maxAgeSeconds = -1,
staleIfErrorSeconds = -1,
staleWhileRevalidateSeconds = -1,
immutable = false,
}) {
const parts = [];
if(mode) {
parts.push(mode);
}
if(maxAgeSeconds >= 0) {
parts.push(`max-age=${maxAgeSeconds}`);
}
if(staleIfErrorSeconds >= 0) {
parts.push(`stale-if-error=${staleIfErrorSeconds}`);
}
if(staleWhileRevalidateSeconds >= 0) {
parts.push(`stale-while-revalidate=${staleWhileRevalidateSeconds}`);
}
if(immutable) {
parts.push('immutable');
}
return parts.join(', ');
}
class RequestHandler {
constructor(method, matcher, handleFn) {
this.method = method;
this.matcher = matcher;
this.handleFn = handleFn;
this.cacheControl = '';
this.allowAllOrigins = false;
this.staticHeaders = [];
this.info = `Custom handler at ${this.method} ${this.matcher}`;
}
setCache(options) {
this.cacheControl = options ? makeCacheControlHeader(options) : '';
return this;
}
setCrossOrigin(allowAll) {
this.allowAllOrigins = allowAll;
return this;
}
addHeader(name, value) {
this.staticHeaders.push({ name, value });
return this;
}
applyCommonHeaders(req, res) {
if(this.allowAllOrigins) {
res.setHeader('Access-Control-Allow-Origin', '*');
}
if(this.cacheControl) {
res.setHeader('Cache-Control', this.cacheControl);
}
for(const header of this.staticHeaders) {
res.setHeader(header.name, header.value);
}
}
apply(req, res, info) {
if(req.method !== this.method) {
return false;
}
const match = this.matcher.exec(req.url);
if(!match) {
return false;
}
if(this.handle(req, res, Object.assign({match}, info)) === false) {
return false;
}
return true;
}
handle(req, res, info) {
return this.handleFn(req, res, info);
}
printInfo(target) {
target.write(this.info + '\n');
}
begin() {
return true;
}
close() {
return true;
}
}
module.exports = {RequestHandler};