Skip to main content
Module

std/node/internal/streams/utils.mjs

Deno standard library
Go to Latest
File
// Copyright 2018-2022 the Deno authors. All rights reserved. MIT license.// Copyright Joyent and Node contributors. All rights reserved. MIT license.// deno-lint-ignore-file
const kIsDisturbed = Symbol("kIsDisturbed");
function isReadableNodeStream(obj) { return !!( obj && typeof obj.pipe === "function" && typeof obj.on === "function" && (!obj._writableState || obj._readableState?.readable !== false) && // Duplex (!obj._writableState || obj._readableState) // Writable has .pipe. );}
function isWritableNodeStream(obj) { return !!( obj && typeof obj.write === "function" && typeof obj.on === "function" && (!obj._readableState || obj._writableState?.writable !== false) // Duplex );}
function isDuplexNodeStream(obj) { return !!( obj && (typeof obj.pipe === "function" && obj._readableState) && typeof obj.on === "function" && typeof obj.write === "function" );}
function isNodeStream(obj) { return ( obj && ( obj._readableState || obj._writableState || (typeof obj.write === "function" && typeof obj.on === "function") || (typeof obj.pipe === "function" && typeof obj.on === "function") ) );}
function isIterable(obj, isAsync) { if (obj == null) return false; if (isAsync === true) return typeof obj[Symbol.asyncIterator] === "function"; if (isAsync === false) return typeof obj[Symbol.iterator] === "function"; return typeof obj[Symbol.asyncIterator] === "function" || typeof obj[Symbol.iterator] === "function";}
function isDestroyed(stream) { if (!isNodeStream(stream)) return null; const wState = stream._writableState; const rState = stream._readableState; const state = wState || rState; return !!(stream.destroyed || state?.destroyed);}
// Have been end():d.function isWritableEnded(stream) { if (!isWritableNodeStream(stream)) return null; if (stream.writableEnded === true) return true; const wState = stream._writableState; if (wState?.errored) return false; if (typeof wState?.ended !== "boolean") return null; return wState.ended;}
// Have emitted 'finish'.function isWritableFinished(stream, strict) { if (!isWritableNodeStream(stream)) return null; if (stream.writableFinished === true) return true; const wState = stream._writableState; if (wState?.errored) return false; if (typeof wState?.finished !== "boolean") return null; return !!( wState.finished || (strict === false && wState.ended === true && wState.length === 0) );}
// Have been push(null):d.function isReadableEnded(stream) { if (!isReadableNodeStream(stream)) return null; if (stream.readableEnded === true) return true; const rState = stream._readableState; if (!rState || rState.errored) return false; if (typeof rState?.ended !== "boolean") return null; return rState.ended;}
// Have emitted 'end'.function isReadableFinished(stream, strict) { if (!isReadableNodeStream(stream)) return null; const rState = stream._readableState; if (rState?.errored) return false; if (typeof rState?.endEmitted !== "boolean") return null; return !!( rState.endEmitted || (strict === false && rState.ended === true && rState.length === 0) );}
function isDisturbed(stream) { return !!(stream && ( stream.readableDidRead || stream.readableAborted || stream[kIsDisturbed] ));}
function isReadable(stream) { const r = isReadableNodeStream(stream); if (r === null || typeof stream?.readable !== "boolean") return null; if (isDestroyed(stream)) return false; return r && stream.readable && !isReadableFinished(stream);}
function isWritable(stream) { const r = isWritableNodeStream(stream); if (r === null || typeof stream?.writable !== "boolean") return null; if (isDestroyed(stream)) return false; return r && stream.writable && !isWritableEnded(stream);}
function isFinished(stream, opts) { if (!isNodeStream(stream)) { return null; }
if (isDestroyed(stream)) { return true; }
if (opts?.readable !== false && isReadable(stream)) { return false; }
if (opts?.writable !== false && isWritable(stream)) { return false; }
return true;}
function isClosed(stream) { if (!isNodeStream(stream)) { return null; }
const wState = stream._writableState; const rState = stream._readableState;
if ( typeof wState?.closed === "boolean" || typeof rState?.closed === "boolean" ) { return wState?.closed || rState?.closed; }
if (typeof stream._closed === "boolean" && isOutgoingMessage(stream)) { return stream._closed; }
return null;}
function isOutgoingMessage(stream) { return ( typeof stream._closed === "boolean" && typeof stream._defaultKeepAlive === "boolean" && typeof stream._removedConnection === "boolean" && typeof stream._removedContLen === "boolean" );}
function isServerResponse(stream) { return ( typeof stream._sent100 === "boolean" && isOutgoingMessage(stream) );}
function isServerRequest(stream) { return ( typeof stream._consuming === "boolean" && typeof stream._dumped === "boolean" && stream.req?.upgradeOrConnect === undefined );}
function willEmitClose(stream) { if (!isNodeStream(stream)) return null;
const wState = stream._writableState; const rState = stream._readableState; const state = wState || rState;
return (!state && isServerResponse(stream)) || !!( state && state.autoDestroy && state.emitClose && state.closed === false );}
export default { isDisturbed, kIsDisturbed, isClosed, isDestroyed, isDuplexNodeStream, isFinished, isIterable, isReadable, isReadableNodeStream, isReadableEnded, isReadableFinished, isNodeStream, isWritable, isWritableNodeStream, isWritableEnded, isWritableFinished, isServerRequest, isServerResponse, willEmitClose,};export { isClosed, isDestroyed, isDisturbed, isDuplexNodeStream, isFinished, isIterable, isNodeStream, isReadable, isReadableEnded, isReadableFinished, isReadableNodeStream, isServerRequest, isServerResponse, isWritable, isWritableEnded, isWritableFinished, isWritableNodeStream, kIsDisturbed, willEmitClose,};