CartoDB-SQL-API/lib/api/middlewares/cache-control.js

35 lines
1.1 KiB
JavaScript

'use strict';
const ONE_YEAR_IN_SECONDS = 31536000; // ttl in cache provider
const FIVE_MINUTES_IN_SECONDS = 60 * 5; // ttl in cache provider
const defaultCacheTTL = {
ttl: ONE_YEAR_IN_SECONDS,
fallbackTtl: FIVE_MINUTES_IN_SECONDS
};
const cacheControl = Object.assign(defaultCacheTTL, global.settings.cache);
module.exports = function cacheControlHeader () {
return function cacheControlHeaderMiddleware (req, res, next) {
const { cachePolicy } = res.locals.params;
const { affectedTables, mayWrite } = res.locals;
if (cachePolicy === 'persist') {
res.header('Cache-Control', `public,max-age=${ONE_YEAR_IN_SECONDS}`);
return next();
}
if (affectedTables && affectedTables.getTables().every(table => table.updated_at !== null)) {
const maxAge = mayWrite ? 0 : cacheControl.ttl;
res.header('Cache-Control', `no-cache,max-age=${maxAge},must-revalidate,public`);
return next();
}
const maxAge = cacheControl.fallbackTtl;
res.header('Cache-Control', `no-cache,max-age=${maxAge},must-revalidate,public`);
return next();
};
};