I am creating a chess engine using nodejs in lambda but due to asynchronous call it showing timeout error on lambda every time. This is just partial part of the function. It is working fine on local nodejs console but not on the lambda. Please someone suggest something as I am new to this.
var chessjs = require('./chess');
var engine = require('uci');
var uciengine = new engine(process.env['LAMBDA_TASK_ROOT'] + '/stockfish');
var fs = require("fs");
var match;
function moveEngine() {
var curfen = "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1";
var depth = '20';
uciengine.runProcess().then(
() => {
console.log("Started.");
return uciengine.uciCommand();
}
).then(
() => {
console.log("Is Ready?");
return uciengine.isReadyCommand();
}
).then(
() => {
console.log("New game.");
return uciengine.uciNewGameCommand();
}
).then(
() => {
console.log("Setting position.");
return uciengine.positionCommand(curfen);
}
).then(
() => {
console.log('Starting position set');
console.log('Starting analysis');
return uciengine.depthLimitedGoCommand(depth, (info) => {
});
}
).then((bestmove) => {
console.log('Bestmove: ');
console.log(bestmove);
return uciengine.quitCommand();
}).then(() => {
console.log('Stopped');
response.sessionAttributes = {};
context.succeed(response);
}).done();
}
async call code
var chessjs = require('./chess');
var engine = require('uci');
var async= require('async');
var uciengine = new engine('/var/task/stockfish');
var fs = require("fs");
var match;
function moveEngine() {
var curfen = "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1";
var depth = '20';
async.auto({
runProcess: function(next, results) {
uciengine.runProcess(next,results);
},
checkUiEngineReady:['runProcess',function(next,results) {
uciengine.checkUiEngineReady(next,results);
}],
newGameCommand:['checkUiEngineReady',function(next,results) {
uciengine.newGameCommand(next,results);
}],
position:['newGameCommand',function(next,results) {
uciengine.positionCommand(curfen,next,results);
}],
godepth:['position',function(next,results) {
uciengine.depthLimitedGoCommand(depth,next,results);
}]
}, function(err, response) {
if (err) {
next(err);
} else {
console.log(response);
uciengine.quitCommand();
context.succeed(response);
}
});
}
moveEngine();
async call is giving the same error like before and i think it is probably wrong.
You can handle the Async call in Lambda using async npm module which is a utility module to handle asynchronous programming in Nodejs.
You can install the async module with npm install --save async.
async.auto function will be useful to manage the above call.
Here is an example through which you can manage your code.
async.auto({
runProcess: function(next, results) {
runProcess(next,results);
},
checkUiEngineReady:['runProcess',function(next,results) {
checkUiEngineReady(next,results);
}],
newGameCommand:['checkUiEngineReady',function(next,results) {
newGameCommand(next,results);
}]
}, function(err, response) {
if (err) {
next(err);
} else {
context.succeed(response);
}
});
Thanks