spawn ENOENT

[samirlegdah]

hi,
great job... but how can i use this binari ?

i tried with https://github.com/sina-masnadi/node-gs

              gs()
                .batch()
                .nopause()
                .option('-r' + 50 * 2)
                .option('-dDownScaleFactor=2')
                .executablePath()
                .device('png16m')
                .output(tempNewPath)
                .input(tempFilePath)
                .exec( (err, stdout, stderr) =>{
                    if (!err) {
                        console.log('gs executed w/o error');
                        console.log('stdout', stdout);
                        console.log('stderr', stderr);
                        //resolve();
                        return true
                    } else {
                        console.log('gs error:', err);
                        //reject(err);
                        return false
                    }
                });
        

but i have this error:

Error: spawn ../lambda-ghostscript/bin/gs ENOENT
    at exports._errnoException (util.js:1020:11)
    at Process.ChildProcess._handle.onexit (internal/child_process.js:197:32)
    at onErrorNT (internal/child_process.js:376:16)
    at _combinedTickCallback (internal/process/next_tick.js:80:11)
    at process._tickDomainCallback (internal/process/next_tick.js:128:9)

I thought the problem was the gs module, so I tried calling the binary file directly with spawn

var path = require('path')
const { spawn } = require('child_process');

var opz = ["-dBATCH","-dNOPAUSE","-r100","-dDownScaleFactor=2","-sDEVICE=png16m","-sOutputFile=/tmp/1-Introduzione_2018.png","/dist/in.pdf"];

var nwDir = path.dirname(process.execPath);
var a = path.join(__dirname,"lambda-ghostscript","bin","gs")
spawn(a, opz).stdout.on("data", function(d) {
    console.log(d);
  });

BUT

Error: spawn c:\Users\Samir\Documents\GitHub\esempi\provaGs\lambda-ghostscript\bin\gs ENOENT
util.js:1024
    at _errnoException (util.js:1024:11)
    at Process.ChildProcess._handle.onexit (internal/child_process.js:192:19)
    at onErrorNT (internal/child_process.js:374:16)
    at _combinedTickCallback (internal/process/next_tick.js:138:11)
    at process._tickCallback (internal/process/next_tick.js:180:9)
    at Function.Module.runMain (module.js:655:11)
    at startup (bootstrap_node.js:187:16)
    at bootstrap_node.js:608:3

what am I doing wrong?? thanks

[mcodina86]

Try using exec instead spawn. See more here

[Codezhak]

@samirlegdah Do you find the solution? I am also got stuck on this. Any suggestion would be appreciated.

[Codezhak]

Solved my issue. It was just a permission issue!!. I added complete permission (r, w, x) using Linux OS and then uploaded to lambda, worked for me.

[adwaitpatankar]

Using the node-gs wrapper and the compiled ghostscript for generating the pdf report. We are able to generate a pdf report when executed on a linux machine. However when executed as part of the AWS lambda function not getting any output. No errors, but not getting in any of the below blocks when added loggers.

proc.stdout.on('data', function (data) {
totalBytes += data.length;
_data.push(data);
});
proc.on('close', function () {
var buf = Buffer.concat(_data, totalBytes);

            return cb.call(self, null, buf.toString());
        });
        process.on('exit', function () {
            proc.kill();
        });

[brunokunace]

@Codezhak i cant test it, you can send a example working with node and gs? only simple example, i can try here and receive errors

[brunokunace]

you can help @sina-masnadi ?

index.js on lambda

exports.handler = async (event) => {
var gs = require('gs');
gs()
    .batch()
    .nopause()
    .option('-r' + 50 * 2)
    .option('-dDownScaleFactor=2')
    .executablePath('/var/tasks/ghostscript/bin/gs')
    .device('png16m')
    .output('tmp/123.png')
    .input('tmp/123.pdf')
    .exec(function (err, stdout, stderr) {
        if (!err) {
		   // no error
		   console.log('no errors')
        } else {
		   // handle errors
		   console.log('deu merda')
        }
	});
};

ghostscript folder, downloaded here https://github.com/sina-masnadi/lambda-ghostscript

[brunokunace]

the console error:

INFO	gs command: -dBATCH,-dNOPAUSE,-r100,-dDownScaleFactor=2,-sDEVICE=png16m,-sOutputFile=tmp/123.png,tmp/123.pdf
ERROR	Uncaught Exception	{"errorType":"Error","errorMessage":"spawn /var/tasks/ghostscript/bin/gs ENOENT","code":"ENOENT","stack":["Error: spawn /var/tasks/ghostscript/bin/gs ENOENT","    at Process.ChildProcess._handle.onexit (internal/child_process.js:240:19)","    at onErrorNT (internal/child_process.js:415:16)","    at process._tickCallback (internal/process/next_tick.js:63:19)"],"errno":"ENOENT","syscall":"spawn /var/tasks/ghostscript/bin/gs","path":"/var/tasks/ghostscript/bin/gs","spawnargs":["-dBATCH","-dNOPAUSE","-r100","-dDownScaleFactor=2","-sDEVICE=png16m","-sOutputFile=tmp/123.png","tmp/123.pdf"]}

when i remove /var/taks and put only: executablePath('ghostscript/bin/gs') i receive it

INFO	gs command: -dBATCH,-dNOPAUSE,-r100,-dDownScaleFactor=2,-sDEVICE=png16m,-sOutputFile=tmp/123.png,tmp/123.pdf
ERROR	Invoke Error	{"errorType":"TypeError","errorMessage":"Cannot read property 'on' of undefined","stack":["TypeError: Cannot read property 'on' of undefined","    at Object.exec (/var/task/node_modules/gs/index.js:91:24)","    at Runtime.exports.handler (/var/task/index.js:34:6)","    at Runtime.handleOnce (/var/runtime/Runtime.js:63:25)","    at process._tickCallback (internal/process/next_tick.js:68:7)"]}
2019-07-12T17:25:14.142Z	bb5844cd-6d2f-4eb7-9b48-1e81e2b2fbbb	ERROR	Uncaught Exception	{"errorType":"Error","errorMessage":"spawn ghostscript/bin/gs EACCES","code":"EACCES","stack":["Error: spawn ghostscript/bin/gs EACCES","    at Process.ChildProcess._handle.onexit (internal/child_process.js:240:19)","    at onErrorNT (internal/child_process.js:415:16)","    at process._tickCallback (internal/process/next_tick.js:63:19)"],"errno":"EACCES","syscall":"spawn ghostscript/bin/gs","path":"ghostscript/bin/gs","spawnargs":["-dBATCH","-dNOPAUSE","-r100","-dDownScaleFactor=2","-sDEVICE=png16m","-sOutputFile=tmp/123.png","tmp/123.pdf"]}

[Codezhak]

Actually what solved my issue is I Just added execution permission for the entire files from Linux system and uploaded to lambda.
While I uploaded from Windows this ENOENT occurs.

[brunokunace]

Actually what solved my issue is I Just added execution permission for the entire files from Linux system and uploaded to lambda.
While I uploaded from Windows this ENOENT occurs.

FINE! you have a example on gist.github.com or repository working?

what version of node you run on lambda? 10?

thanks so much

[Codezhak]

I tested with the sample code given in the readme.
My node version is 10 on lambda.

[n123456789k]

@Codezhak @brunokunace did you find what was causing this error, running it on lambda and it's throwing this:

Error: spawn gs ENOENT
at exports._errnoException (util.js:1018:11)
at Process.ChildProcess._handle.onexit (internal/child_process.js:193:32)
at onErrorNT (internal/child_process.js:367:16)
at _combinedTickCallback (internal/process/next_tick.js:80:11)
at process._tickDomainCallback (internal/process/next_tick.js:128:9)

[brunokunace]

@narwy i solve this change permissions of folders before send it to lambda, on windows i cant fiz it, only in mac or linux, for chmod method

[n123456789k]

@brunokunace it’s just recently happened the function hasn’t been updated for 9 months on lambda and is throwing this error. Is your lambda function still working can you share your function please ?

[adwaitpatankar]

It has worked in my case too with following things:

• Have to give execute permissions on the "gs" executable on a linux machine.
• Build the lambda function zip on the linux machien and update the lambda function using the aws command line.

Another thing I had tried was I had to make use of spawnsync instead of spawn as in, my requirement was to generate the pdf report and send it back as response to the API Gateway.