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@trpc/server

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The tRPC server library

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'use strict'; var unpromise = require('../../../vendor/unpromise/unpromise.js'); var asyncIterable = require('./asyncIterable.js'); var timerResource = require('./timerResource.js'); function _ts_add_disposable_resource(env, value, async) { if (value !== null && value !== void 0) { if (typeof value !== "object" && typeof value !== "function") throw new TypeError("Object expected."); var dispose, inner; if (async) { if (!Symbol.asyncDispose) throw new TypeError("Symbol.asyncDispose is not defined."); dispose = value[Symbol.asyncDispose]; } if (dispose === void 0) { if (!Symbol.dispose) throw new TypeError("Symbol.dispose is not defined."); dispose = value[Symbol.dispose]; if (async) inner = dispose; } if (typeof dispose !== "function") throw new TypeError("Object not disposable."); if (inner) dispose = function() { try { inner.call(this); } catch (e) { return Promise.reject(e); } }; env.stack.push({ value: value, dispose: dispose, async: async }); } else if (async) { env.stack.push({ async: true }); } return value; } function _ts_dispose_resources(env) { var _SuppressedError = typeof SuppressedError === "function" ? SuppressedError : function(error, suppressed, message) { var e = new Error(message); return e.name = "SuppressedError", e.error = error, e.suppressed = suppressed, e; }; return (_ts_dispose_resources = function _ts_dispose_resources(env) { function fail(e) { env.error = env.hasError ? new _SuppressedError(e, env.error, "An error was suppressed during disposal.") : e; env.hasError = true; } var r, s = 0; function next() { while(r = env.stack.pop()){ try { if (!r.async && s === 1) return s = 0, env.stack.push(r), Promise.resolve().then(next); if (r.dispose) { var result = r.dispose.call(r.value); if (r.async) return s |= 2, Promise.resolve(result).then(next, function(e) { fail(e); return next(); }); } else s |= 1; } catch (e) { fail(e); } } if (s === 1) return env.hasError ? Promise.reject(env.error) : Promise.resolve(); if (env.hasError) throw env.error; } return next(); })(env); } const PING_SYM = Symbol('ping'); /** * Derives a new {@link AsyncGenerator} based of {@link iterable}, that yields {@link PING_SYM} * whenever no value has been yielded for {@link pingIntervalMs}. */ async function* withPing(iterable, pingIntervalMs) { const env = { stack: [], error: void 0, hasError: false }; try { const iterator = _ts_add_disposable_resource(env, asyncIterable.iteratorResource(iterable), true); ; // declaration outside the loop for garbage collection reasons let result; let nextPromise = iterator.next(); while(true){ const env = { stack: [], error: void 0, hasError: false }; try { const pingPromise = _ts_add_disposable_resource(env, timerResource.timerResource(pingIntervalMs), false); ; result = await unpromise.Unpromise.race([ nextPromise, pingPromise.start() ]); if (result === timerResource.disposablePromiseTimerResult) { // cancelled yield PING_SYM; continue; } if (result.done) { return result.value; } nextPromise = iterator.next(); yield result.value; // free up reference for garbage collection result = null; } catch (e) { env.error = e; env.hasError = true; } finally{ _ts_dispose_resources(env); } } } catch (e) { env.error = e; env.hasError = true; } finally{ const result = _ts_dispose_resources(env); if (result) await result; } } exports.PING_SYM = PING_SYM; exports.withPing = withPing;