smc-hub
Version:
CoCalc: Backend webserver component
226 lines • 10.4 kB
JavaScript
"use strict";
/*
* This file is part of CoCalc: Copyright © 2020 Sagemath, Inc.
* License: AGPLv3 s.t. "Commons Clause" – see LICENSE.md for details
*/
var __extends = (this && this.__extends) || (function () {
var extendStatics = function (d, b) {
extendStatics = Object.setPrototypeOf ||
({ __proto__: [] } instanceof Array && function (d, b) { d.__proto__ = b; }) ||
function (d, b) { for (var p in b) if (Object.prototype.hasOwnProperty.call(b, p)) d[p] = b[p]; };
return extendStatics(d, b);
};
return function (d, b) {
if (typeof b !== "function" && b !== null)
throw new TypeError("Class extends value " + String(b) + " is not a constructor or null");
extendStatics(d, b);
function __() { this.constructor = d; }
d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
};
})();
var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, P, generator) {
function adopt(value) { return value instanceof P ? value : new P(function (resolve) { resolve(value); }); }
return new (P || (P = Promise))(function (resolve, reject) {
function fulfilled(value) { try { step(generator.next(value)); } catch (e) { reject(e); } }
function rejected(value) { try { step(generator["throw"](value)); } catch (e) { reject(e); } }
function step(result) { result.done ? resolve(result.value) : adopt(result.value).then(fulfilled, rejected); }
step((generator = generator.apply(thisArg, _arguments || [])).next());
});
};
var __generator = (this && this.__generator) || function (thisArg, body) {
var _ = { label: 0, sent: function() { if (t[0] & 1) throw t[1]; return t[1]; }, trys: [], ops: [] }, f, y, t, g;
return g = { next: verb(0), "throw": verb(1), "return": verb(2) }, typeof Symbol === "function" && (g[Symbol.iterator] = function() { return this; }), g;
function verb(n) { return function (v) { return step([n, v]); }; }
function step(op) {
if (f) throw new TypeError("Generator is already executing.");
while (_) try {
if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
if (y = 0, t) op = [op[0] & 2, t.value];
switch (op[0]) {
case 0: case 1: t = op; break;
case 4: _.label++; return { value: op[1], done: false };
case 5: _.label++; y = op[1]; op = [0]; continue;
case 7: op = _.ops.pop(); _.trys.pop(); continue;
default:
if (!(t = _.trys, t = t.length > 0 && t[t.length - 1]) && (op[0] === 6 || op[0] === 2)) { _ = 0; continue; }
if (op[0] === 3 && (!t || (op[1] > t[0] && op[1] < t[3]))) { _.label = op[1]; break; }
if (op[0] === 6 && _.label < t[1]) { _.label = t[1]; t = op; break; }
if (t && _.label < t[2]) { _.label = t[2]; _.ops.push(op); break; }
if (t[2]) _.ops.pop();
_.trys.pop(); continue;
}
op = body.call(thisArg, _);
} catch (e) { op = [6, e]; y = 0; } finally { f = t = 0; }
if (op[0] & 5) throw op[1]; return { value: op[0] ? op[1] : void 0, done: true };
}
};
var __read = (this && this.__read) || function (o, n) {
var m = typeof Symbol === "function" && o[Symbol.iterator];
if (!m) return o;
var i = m.call(o), r, ar = [], e;
try {
while ((n === void 0 || n-- > 0) && !(r = i.next()).done) ar.push(r.value);
}
catch (error) { e = { error: error }; }
finally {
try {
if (r && !r.done && (m = i["return"])) m.call(i);
}
finally { if (e) throw e.error; }
}
return ar;
};
Object.defineProperty(exports, "__esModule", { value: true });
exports.query = void 0;
/*
Does the queries to update changefeeds, deduplicating across
both all changefeeds and a small interval of time.
*/
// set to false to completely disable for debugging/testing
var THROTTLE = true;
// 10ms when running unit tests, still throttle, but make it quick.
// Otherwise, we default to 250ms, which is enough to be massively
// useful, but also not noticed by user.
var THROTTLE_MS = process.env.SMC_TEST ? 10 : 500;
// THROTTLE_MS can be overridden the POSTGRES_THROTTLE_CHANGEFEED_MS
// environment variable.
if (process.env.POSTGRES_THROTTLE_CHANGEFEED_MS != null) {
THROTTLE_MS = parseInt(process.env.POSTGRES_THROTTLE_CHANGEFEED_MS);
}
var events_1 = require("events");
var awaiting_1 = require("awaiting");
var async_utils_1 = require("smc-util/async-utils");
var misc_1 = require("smc-util/misc");
var _a = require("../postgres-base"), one_result = _a.one_result, all_results = _a.all_results;
function key(obj) {
return "query-" + JSON.stringify(obj);
}
var ThrottledTableQueue = /** @class */ (function (_super) {
__extends(ThrottledTableQueue, _super);
function ThrottledTableQueue(db, table, interval_ms) {
var _this = _super.call(this) || this;
_this.queue = {};
_this.state = "ready";
_this.db = db;
_this.table = table;
_this.interval_ms = interval_ms;
// client listens for results of query -- if queries pile up, and
// there are many tables, the default of 10 can easily be exceeded.
_this.setMaxListeners(100);
return _this;
}
ThrottledTableQueue.prototype.dbg = function (f) {
return this.db._dbg("ThrottledTableQueue('" + this.table + "')." + f);
};
ThrottledTableQueue.prototype.close = function () {
if (this.state == "closed") {
return;
}
if (this.process_timer != null) {
clearTimeout(this.process_timer);
}
for (var k in this.queue) {
this.emit(k, "closed");
}
this.emit("closed");
this.removeAllListeners();
misc_1.close(this);
this.state = "closed";
};
ThrottledTableQueue.prototype.enqueue = function (query) {
if (this.state == "closed") {
throw Error("trying to enqueue after close");
}
var k = key(query);
this.queue[k] = query;
if (this.process_timer == null) {
this.dbg("enqueue")("will process queue in " + this.interval_ms + "ms...");
this.process_timer = setTimeout(this.process_queue.bind(this), this.interval_ms);
}
return k;
};
ThrottledTableQueue.prototype.process_queue = function () {
return __awaiter(this, void 0, void 0, function () {
var dbg, queue, _a, _b, _i, k, _c, select, where, result, err_1;
return __generator(this, function (_d) {
switch (_d.label) {
case 0:
dbg = this.dbg("process_queue");
delete this.process_timer; // it just fired
queue = misc_1.copy(this.queue);
this.queue = {};
_a = [];
for (_b in queue)
_a.push(_b);
_i = 0;
_d.label = 1;
case 1:
if (!(_i < _a.length)) return [3 /*break*/, 6];
k = _a[_i];
dbg(k);
_c = queue[k], select = _c.select, where = _c.where;
_d.label = 2;
case 2:
_d.trys.push([2, 4, , 5]);
return [4 /*yield*/, awaiting_1.callback(one_query, this.db, select, this.table, where)];
case 3:
result = _d.sent();
if (this.state == "closed")
return [2 /*return*/];
dbg("success", k);
this.emit(k, undefined, result);
return [3 /*break*/, 5];
case 4:
err_1 = _d.sent();
if (this.state == "closed")
return [2 /*return*/];
dbg("fail", k);
this.emit(k, err_1, undefined);
return [3 /*break*/, 5];
case 5:
_i++;
return [3 /*break*/, 1];
case 6: return [2 /*return*/];
}
});
});
};
return ThrottledTableQueue;
}(events_1.EventEmitter));
var throttled_table_queues = {};
function throttled_table_queue(db, table, interval_ms) {
if (throttled_table_queues[table] != null) {
return throttled_table_queues[table];
}
return (throttled_table_queues[table] = new ThrottledTableQueue(db, table, interval_ms));
}
function query(opts) {
return __awaiter(this, void 0, void 0, function () {
var Table, k, _a, err, result;
return __generator(this, function (_b) {
switch (_b.label) {
case 0:
if (!(THROTTLE && opts.one)) return [3 /*break*/, 2];
Table = throttled_table_queue(opts.db, opts.table, THROTTLE_MS);
k = Table.enqueue({ select: opts.select, where: opts.where });
return [4 /*yield*/, async_utils_1.once(Table, k)];
case 1:
_a = __read.apply(void 0, [_b.sent(), 2]), err = _a[0], result = _a[1];
if (err != null) {
throw err;
}
return [2 /*return*/, result];
case 2: return [4 /*yield*/, awaiting_1.callback(opts.one ? one_query : all_query, opts.db, opts.select, opts.table, opts.where)];
case 3: return [2 /*return*/, _b.sent()];
}
});
});
}
exports.query = query;
function all_query(db, select, table, where, cb) {
db._query({ select: select, table: table, where: where, cb: all_results(cb) });
}
function one_query(db, select, table, where, cb) {
db._query({ select: select, table: table, where: where, cb: one_result(cb) });
}
//# sourceMappingURL=changefeed-query.js.map