AWS Lambda - NodeJS POST request and asynch write/read file

Question

I am new to NodeJS and inside of AWS Lambda I am trying to make a POST request that calls an external API with a JSON object, creates a document with the response and then r

Answer 1

In general, I'd recommend starting like this:

var querystring = require('querystring');
var https = require('https');
var fs = require('fs');

exports.handler = function(event, context) {
    console.info('Received event', event);

    var data = {
        "accessKey": accessKey,
        "templateName": templateName,
        "outputName": outputName,
        "data": event.data
    };

    // Build the post string from an object
    var post_data = JSON.stringify(data);

    // An object of options to indicate where to post to
    var post_options = {
        host: 'hostname.com',
        port: '443',
        path: '/path/to/api',
        method: 'POST',
        headers: {
            'Content-Type': 'application/json',
            'Content-Length': post_data.length
        }
    };

    var post_request = https.request(post_options, function(res) {
        var body = '';

        res.on('data', function(chunk)  {
            body += chunk;
        });

        res.on('end', function() {
            context.done(body);
        });

        res.on('error', function(e) {
            context.fail('error:' + e.message);
        });
    });

    // post the data
    post_request.write(post_data);
    post_request.end();
};

You can see I simplified your code quite a bit. I'd recommend avoiding the file system since that would slow down your program. I'm also not sure about what is the real goal of your function so I just return the HTTP response.