How can i respond with JSON with a Lambda function - javascript

Below I am trying to repond to a GET with the weather in JSON format. I am attempting the use the const done in order to deliver the response. This does not seem to work. I get the response and weather in console but return nothing to the client.
'use strict';
console.log('Loading function');
const doc = require('dynamodb-doc');
const http = require('http');
const dynamo = new doc.DynamoDB();
function get_json(url, callback) {
http.get(url, function(res) {
var body = '';
res.on('data', function(chunk) {
body += chunk;
});
res.on('end', function() {
var response = JSON.parse(body);
callback(response);
});
});
}
exports.handler = (event, context, callback) => {
const done = (err, res) => callback(null, {
statusCode: err ? '400' : '200',
body: err ? err.message : JSON.stringify(res),
headers: {
'Content-Type': 'application/json',
},
});
switch (event.httpMethod) {
case 'DELETE':
dynamo.deleteItem(JSON.parse(event.body), done)
break;
case 'GET':
// dynamo.scan({ TableName: event.queryStringParameters.TableName }, done);
done(get_json("http://api.openweathermap.org/data/2.5/weather?q=London,uk&appid=92f14e06a6652e81a5a58bd13d152f70", callback, function (resp) {
callback(resp);
}));
break;
}
};

get_json() doesn't return anything, so passing it into done is definitely the wrong thing to do.
It looks like you need to do this:
get_json(
"http://api.openweathermap.org/data/2.5/weather?q=London,uk&appid=92f14e06a6652e81a5a58bd13d152f70",
resp => done(null, resp)
);

Related

how to resolve 'NodeJS API call response is an un-parsable object'?

I am getting the below result after my API call.
My node version is 12.x
{"type":"Buffer","data":[123,34,101,114,114,111,114,115,34,58,91,34,74,87,84,32,105,115,32,101,120,112,105,114,101,100,32,111,114,32,100,111,101,115,32,110,111,116,32,104,97,118,101,32,112,114,111,112,101,114,32,39,101,120,112,39,32,99,108,97,105,109,34,93,125,11]}
Please see the code snippet below:
let postOptions = {
host: 'vault.server',
path: '/v1/auth/gcp/login',
method: HTTPS.POST_REQUEST,
headers: {
'Content-Type': 'application/json; charset=utf-8',
'X-Vault-Namespace': 'mynamespace'
},
json: true,
rpDefaults: {
strictSSL: false
}
};
let requestPayLoad = {
"role": this._vaultRole,
"jwt": signedJWT
};
console.log(JSON.stringify(requestPayLoad));
console.log(JSON.stringify(postOptions));
try {
let result = await HTTPS.makeRequest(postOptions, JSON.stringify(requestPayLoad), HTTPS.POST_REQUEST);
console.log('Response***************',JSON.stringify(result));
return result.auth.client_token;
}
Please see the below code snippet for the http make request method.
return new Promise((resolve, reject) => {
let rq = https.request(options, (res) => {
let response;
let chunks = [];
res.on('data', (chunk) => {
chunks.push(chunk);
});
res.on('end', () => {
response = Buffer.concat(chunks);
return resolve(response);
});
});
rq.on('error', (e) => {
return reject({'statusCode': 500, 'success': false, 'error': e.toString()});
});
if (type === 'POST') {
rq.write(data);
}
rq.end();
});
Please help me to resolve this
You are receiving the data as a Buffer. Use the toString() method to convert this buffer into a string inside the try block.
try {
let result = await HTTPS.makeRequest(postOptions, JSON.stringify(requestPayLoad), HTTPS.POST_REQUEST);
console.log('Response***************', result.toString());
return result.auth.client_token;
}
If you want to access the data from the response returned from you API call
do:
let data = result.data;
and I you want to get client_token as showing here:
return result.auth.client_token;
it's not possible because the response does not have auth attribute on it:
{"type":"Buffer","data":[123,34,101,114,114,111,114,115,34,58,91,34,74,87,84,32,105,115,32,101,120,112,105,114,101,100,32,111,114,32,100,111,101,115,32,110,111,116,32,104,97,118,101,32,112,114,111,112,101,114,32,39,101,120,112,39,32,99,108,97,105,109,34,93,125,11]}

How to get a variable out of http request NodeJS?

I would like to use two IBM Watson services and combine the responses from both in one variable and return it as a callback. I couldn't figure out how to get response1 value outside the http request to combine it with response2 from the other IBM Watson service.
I tried the below code and it didn't work. I read that I can use promises, but I'm pretty new to this, and couldn't figure out how to do this.
Can anyone help please?
const AWS = require('aws-sdk');
var http = require('https');
exports.handler = (event, context, callback) => {
var text = JSON.stringify(event.text);
var options = {
method: process.env.method,
hostname: process.env.watson_hostname,
port: null,
path: process.env.path,
headers: {
'content-type': process.env.content_type,
authorization: process.env.authorization,
'cache-control': process.env.cache_control,
'X-Watson-Learning-Opt-Out': 'true'
}
};
var req = http.request(options, function (res) {
var chunks = "";
res.on("data", function (chunk) {
chunks+ = chunk.toString();;
});
res.on("end", function () {
var response1 = (chunks);
//////////////here I need to get reponse2
var response2 = IBM2();
var bothResponses = response1 + response2
callback(null,bothResponses)
});
})
req.write(text);
req.end()
function IBM2(){
var text = JSON.stringify(event.text);
var options = {
method: process.env.method2,
hostname: process.env.watson_hostname2,
port: null,
path: process.env.path2,
headers: {
'content-type': process.env.content_type2,
authorization: process.env.authorization2,
'cache-control': process.env.cache_control,
'X-Watson-Learning-Opt-Out': 'true'
}
};
var req = http.request(options, function (res) {
var chunks = [];
res.on("data", function (chunk) {
chunks.push(chunk);
});
res.on("end", function () {
var response2 = JSON.parse(Buffer.concat(chunks));
return(response2)
}
Return a promise from your IBM2 function and handle using async await in the calling function. Notice the async keyword before on end callback.
I have tried to add Promise to your existing flow:
const AWS = require('aws-sdk');
var http = require('https');
exports.handler = (event, context, callback) => {
var text = JSON.stringify(event.text);
var options = {
method: process.env.method,
hostname: process.env.watson_hostname,
port: null,
path: process.env.path,
headers: {
'content-type': process.env.content_type,
authorization: process.env.authorization,
'cache-control': process.env.cache_control,
'X-Watson-Learning-Opt-Out': 'true'
}
};
var req = http.request(options, function (res) {
var chunks = "";
res.on("data", function (chunk) {
chunks += chunk.toString();;
});
res.on("end", async function () {
var response1 = (chunks);
//////////////here I need to get reponse2
var response2 = await IBM2();
// validate response2 (in case IBM2 throws error)
var bothResponses = response1 + response2;
callback(null,bothResponses)
});
});
req.write(text);
req.end();
function IBM2(){
return new Promise((resolve, reject) =>{
var text = JSON.stringify(event.text);
var options = {
method: process.env.method2,
hostname: process.env.watson_hostname2,
port: null,
path: process.env.path2,
headers: {
'content-type': process.env.content_type2,
authorization: process.env.authorization2,
'cache-control': process.env.cache_control,
'X-Watson-Learning-Opt-Out': 'true'
}
};
var req = http.request(options, function (res) {
var chunks = [];
res.on("data", function (chunk) {
chunks.push(chunk);
});
res.on("end", function () {
var response2 = JSON.parse(Buffer.concat(chunks));
resolve(response2)
});
res.on("error", function (err) {
reject(err);
});
})
});
}
};
Before making any changes to your code, I would suggest you go thru these topics first.
For reference, do take a look into the concept of promises and async-await
Promiese
Async/Await
Dont know if you have other errors, but it looks like youre not waiting for response2 to finish, maybe something like
const response2 = await IBM2():
or if you want to use promises maybe something like:
res.on('end', function () {
var response2 = IBM2().then(
val => {
var bothResponses = response1 + val;
callback(null, bothResponses);
},
reject => {
/* handle rejection here */
},
);
});

Use a value from a function into another function nodejs express

I want to return the value that has been declared in the first Function CreateTag and using it as variable in the second Function CreateStream, but it won't work..
I'm working with nodejs Express.
I try to use RETURN but it won't work..
I have tried it in differance ways, but still not work..
Can you someone help me, please?
'use strict';
var express = require('express');
var router = express.Router();
/* GET home page. */
//Function 1: createTag
var createTag = function hi (TanentValue) {
var https = require('https');
var data = JSON.stringify({
name: TanentValue,
schemaPath: "Tag"
});
var options = {
hostname: 'qlik_dev.be',
path: '/meteor/qrs/tag?xrfkey=1234567890123456',
method: 'POST',
headers: {
'x-qlik-xrfkey': '1234567890123456',
'hdr-usr': 'gak\\gaka',
'Content-Type': 'application/json'
},
};
var req = https.request(options, (res) => {
//console.log(res)
res.on('data', (d) => {
console.log("hi tag")
var getResult = "GaLvAnI"; // ----> return this and use it into the function createStream
return getResult;
})
})
;
req.on('error', (error) => {
console.error(error)
});
req.write(data);
req.end();
}
//Function 2: createStream
var createStream = function (TanentValue) {
var https = require('https');
var galvani = hi(); // --------> here I made a variable to call return value
var data = JSON.stringify({
name: TanentValue,
});
var options = {
hostname: 'qlik_dev.be',
path: '/meteor/qrs/stream?xrfkey=1234567890123456',
method: 'POST',
headers: {
'x-qlik-xrfkey': '1234567890123456',
'hdr-usr': 'gak\\gaka',
'Content-Type': 'application/json'
},
};
var req = https.request(options, (res) => {
res.on('data', (d) => {
console.log(galvani); // -----> use the variable here
})
})
;
req.on('error', (error) => {
console.error(error)
});
req.write(data);
req.end();
}
//homepage
router.get('/', function (req, res) {
res.render('index', { title: 'MCS Test' });
});
//create
router.post('/create', function (req, res) {
//create tag
console.log('POST / Call Create Tag');
createTag(req.body.TanentValue);
//create stream
console.log('POST / Call Create Stream');
createStream(req.body.TanentValue);
res.send('Stream and Tag has been created');
});
module.exports = router;
you can not directly return value from async function. you have to use promise. something like this:
'use strict';
var express = require('express');
var router = express.Router();
/* GET home page. */
//Function 1: createTag
var createTag = function (TanentValue) { // function should be anonymouse
return new Promise((resolve, reject) => {
var https = require('https');
var data = JSON.stringify({
name: TanentValue,
schemaPath: "Tag"
});
var options = {
hostname: 'qlik_dev.be',
path: '/meteor/qrs/tag?xrfkey=1234567890123456',
method: 'POST',
headers: {
'x-qlik-xrfkey': '1234567890123456',
'hdr-usr': 'gak\\gaka',
'Content-Type': 'application/json'
},
};
var req = https.request(options, (res) => {
//console.log(res)
res.on('data', (d) => {
console.log("hi tag")
var getResult = "GaLvAnI"; // ----> return this and use it into the function createStream
resolve(getResult); // success call
})
})
;
req.on('error', (error) => {
reject(error); // error call
});
req.write(data);
req.end();
});
}
//Function 2: createStream
var createStream = function (TanentValue) {
createTag().then((val) => {
var https = require('https');
var galvani = val; // use that value from sucess call
var data = JSON.stringify({
name: TanentValue,
});
var options = {
hostname: 'qlik_dev.be',
path: '/meteor/qrs/stream?xrfkey=1234567890123456',
method: 'POST',
headers: {
'x-qlik-xrfkey': '1234567890123456',
'hdr-usr': 'gak\\gaka',
'Content-Type': 'application/json'
},
};
var req = https.request(options, (res) => {
res.on('data', (d) => {
console.log(galvani); // -----> use the variable here
})
})
;
req.on('error', (error) => {
console.error(error)
});
req.write(data);
req.end();
})
.catch((error) => {
// handle error from createTag function here
});
}
//homepage
router.get('/', function (req, res) {
res.render('index', { title: 'MCS Test' });
});
//create
router.post('/create', function (req, res) {
//create tag
console.log('POST / Call Create Tag');
createTag(req.body.TanentValue);
//create stream
console.log('POST / Call Create Stream');
createStream(req.body.TanentValue);
res.send('Stream and Tag has been created');
});
module.exports = router;
You can solve it using just callback function or the promise.
Using callbacks.
'use strict';
var express = require('express');
var router = express.Router();
/* GET home page. */
//Function 1: createTag
var createTag = (TanentValue, callback) => {
var https = require('https');
var data = JSON.stringify({
name: TanentValue,
schemaPath: "Tag"
});
var options = {
hostname: 'qlik_dev.be',
path: '/meteor/qrs/tag?xrfkey=1234567890123456',
method: 'POST',
headers: {
'x-qlik-xrfkey': '1234567890123456',
'hdr-usr': 'gak\\gaka',
'Content-Type': 'application/json'
},
};
var req = https.request(options, (res) => {
res.on('data', (d) => {
console.log("hi tag")
var getResult = "GaLvAnI"; // ----> return this and use it into the function createStream
callback(false, getResult);
})
});
req.on('error', (error) => {
//console.error(error)
callback(true, error);
});
req.write(data);
req.end();
}
//Function 2: createStream
var createStream = (TanentValue, callback) => {
var https = require('https');
var data = JSON.stringify({
name: TanentValue,
});
var options = {
hostname: 'qlik_dev.be',
path: '/meteor/qrs/stream?xrfkey=1234567890123456',
method: 'POST',
headers: {
'x-qlik-xrfkey': '1234567890123456',
'hdr-usr': 'gak\\gaka',
'Content-Type': 'application/json'
},
};
createTag(TanentValue, (is_error, galvani) => {
if(err || !data){
// do error handling...
callback(true); // true for there was an error
}else{
var req = https.request(options, (res) => {
res.on('data', (d) => {
callback(false);
console.log(galvani); // -----> use the variable here
})
});
req.on('error', (error) => {
callback(true);
console.error(error)
});
req.write(data);
req.end();
}
})
}
//homepage
router.get('/', function (req, res) {
res.render('index', { title: 'MCS Test' });
});
//create
router.post('/create', function (req, res) {
/*
// Since the stream seems to depend on the tag created,
// you don't need to call createTag explicitly because
// it is always/already called from createStream.
//create tag
console.log('POST / Call Create Tag');
createTag(req.body.TanentValue, function(is_error, data){
if(!is_error){
// do something
}else{
// do error handling
console.error(error);
res.send('Tag could not be created, please try later again..');
}
});
*/
//create stream
console.log('POST / Call Create Stream');
createStream(req.body.TanentValue, is_error => {
if(!is_error){
res.send('Stream and Tag has been created');
}else{
res.send('Stream could not be created, please try later again..');
}
});
});
module.exports = router;
Using Promise
'use strict';
var express = require('express');
var router = express.Router();
/* GET home page. */
//Function 1: createTag
var createTag = TanentValue => {
var https = require('https');
var data = JSON.stringify({
name: TanentValue,
schemaPath: "Tag"
});
var options = {
hostname: 'qlik_dev.be',
path: '/meteor/qrs/tag?xrfkey=1234567890123456',
method: 'POST',
headers: {
'x-qlik-xrfkey': '1234567890123456',
'hdr-usr': 'gak\\gaka',
'Content-Type': 'application/json'
},
};
return new Promise((resolve, reject) => {
var req = https.request(options, (res) => {
res.on('data', (d) => {
console.log("hi tag")
var getResult = "GaLvAnI"; // ----> return this and use it into the function createStream
resolve(getResult);
})
});
req.on('error', (error) => {
//console.error(error)
reject(error);
});
req.write(data);
req.end();
})
}
//Function 2: createStream
var createStream = TanentValue => {
var https = require('https');
var data = JSON.stringify({
name: TanentValue,
});
var options = {
hostname: 'qlik_dev.be',
path: '/meteor/qrs/stream?xrfkey=1234567890123456',
method: 'POST',
headers: {
'x-qlik-xrfkey': '1234567890123456',
'hdr-usr': 'gak\\gaka',
'Content-Type': 'application/json'
},
};
createTag(TanentValue).then( galvani => {
return new Promise((resolve, reject) => {
var req = https.request(options, (res) => {
res.on('data', (d) => {
console.log(galvani); // -----> use the variable here
resolve(d);
})
});
req.on('error', (error) => {
console.error(error)
reject({ msg: 'request error while creating the stream', error: error})
});
req.write(data);
req.end();
})
}).catch( error => {
// do error handling...
reject({msg: 'Error while creating a tag', error: error}); // true for there was an error
});
}
//homepage
router.get('/', function (req, res) {
res.render('index', { title: 'MCS Test' });
});
//create
router.post('/create', function (req, res) {
/*
// Since the stream seems to depend on the tag created,
// you don't need to call createTag explicitly because
// it is always/already called from createStream.
//create tag
console.log('POST / Call Create Tag');
createTag(req.body.TanentValue).then( data => {
// do something
}).catch( error => {
// do error handling
});
*/
//create stream
console.log('POST / Call Create Stream');
createStream(req.body.TanentValue).then( data => {
res.send('Stream and Tag has been created');
}).catch(error => {
// 'Stream could not be created, please try later again..'
res.send(error.msg);
});
});
module.exports = router;
Very handfull!! thank you it works!
But while passing the data (Json) from function 1 to function 2 with Promise, the data (json) is undefine in function 2. If I pass a data (String) from function 1 to function 2 than it works..
Why does it give me 'undefine' when it is a json?
//var id;
var req = https.request(options, (res) => {
//console.log(res)
res.setEncoding('utf8');
res.on('data', function (data) {
var json = JSON.parse(data);
var TagId = JSON.stringify(json[0]);
console.log("2 hi getTap");
console.log(TagId); // -------> here it works well
resolve(TagId);
});
});
var req = https.request(options, (res) => {
res.on('data', (d) => {
console.log("3 hi createStream");
console.log(galvani); // -------> here it doesn't work.. it gives me undefine
})
});
here a printscreen of response

javascript promise callback

I am calling a javascript function , which in turn calls a web service;The response of this service is used to call another function which also calls a service. At end of both services we set session attributes. This code gives no errors, but the callback gets called before the service has returned data. The main motive of this code is to set the session attributes before return of flow from this code, when the callback gets called before the service has returned values the session attributes are not set and the requirement of the code is not fulfilled.
'use strict';
function close(sessionAttributes, fulfillmentState, message) {
return {
sessionAttributes,
dialogAction: {
type: 'Close',
fulfillmentState,
message : 'For security purpose answer these questions '
},
};
}
function getSecurityQuestions(intentRequest, context, post_options, callback){
const sessionAttributes = intentRequest.sessionAttributes || {};
var policynumber = sessionAttributes.policynumber;
var interactionID = sessionAttributes.interactionID;
var body = "";
var body2;
const http = require('https');
const promise = new Promise((resolve, reject) => {
const post_data = JSON.stringify({"Purpose":"SecurityQuestions", "InteractionID":interactionID, "SearchStringAcctNum":policynumber});
//ignores SSL
process.env.NODE_TLS_REJECT_UNAUTHORIZED = "0";
var post_request = http.request(post_options, function(res) {
res.on('data', function(chunk) {
body += chunk;
});
res.on('end', function() {
context.done(body);
resolve(body);
});
res.on('error', function(e) {
reject(Error(e.message));
context.fail('error:' + e.message);
});
});
// post the data
post_request.write(post_data);
post_request.end();
});
callback( promise.then((body) => {
body2 = JSON.parse(body);
sessionAttributes.question1 = body2.SecurityDetails[0].Question;
close(sessionAttributes, 'Fulfilled');
}, (error) => {
console.log(error.message);
})
);
}
function getInteraction(intentRequest, context, callback) {
const slots = intentRequest.currentIntent.slots;
var policynumber = "PA"+slots.PolicyNumber;
var questionOne = slots.questionOne;
var questionTwo = slots.questionTwo;
const sessionAttributes = intentRequest.sessionAttributes || {};
console.log("policy number : "+policynumber + "question 1 : "+questionOne + "question 2 : "+questionTwo);
sessionAttributes.policynumber = policynumber;
var body = "";
var body2;
// An object of options to indicate where to post to
var post_options = {
host: 'example.com',
protocol: 'https:',
port: '3000',
path: '/hiddenPath',
method: 'POST',
headers: {
'Content-Type': 'application/json'
}
};
const http = require('https');
const promise = new Promise((resolve, reject) => {
const post_data = JSON.stringify({"Purpose":"CreateInteraction"});
//ignores SSL
process.env.NODE_TLS_REJECT_UNAUTHORIZED = "0";
var post_request = http.request(post_options, function(res) {
res.on('data', function(chunk) {
body += chunk;
});
res.on('end', function() {
context.done(body);
resolve(body);
});
res.on('error', function(e) {
console.log("rejected here");
reject(Error(e.message));
context.fail('error:' + e.message);
});
});
// post the data
post_request.write(post_data);
post_request.end();
});
callback( promise.then((body) => {
body2 = JSON.parse(body);
console.log("interaction ID : "+body2.InteractionID);
sessionAttributes.interactionID = body2.InteractionID;
getSecurityQuestions(intentRequest, context, post_options, callback);
}, (error) => {
console.log('Promise rejected.');
console.log(error.message);
}));
}
// --------------- Intents -----------------------
/**
* Called when the user specifies an intent for this skill.
*/
function dispatch(intentRequest, context, callback) {
const intentName = intentRequest.currentIntent.name;
if (intentName === 'currIntent') {
return getInteraction(intentRequest, context, callback);
}
throw new Error(`Intent with name ${intentName} not supported`);
}
// --------------- Main handler -----------------------
function loggingCallback(response, originalCallback) {
console.log("logging callback called......");
originalCallback(null, response);
}
exports.handler = (event, context, callback) => {
try {
dispatch(event, context, (response) => loggingCallback(response, callback));
} catch (err) {
callback(err);
}
};
You should resolve your promise only after the request ends.. Have updated your sample below. Hope it helps. Also, you were sending an invalid object as your post body. Fixed that as well.
function getValue(context, post_options, callback) {
var body = "";
var body2;
const http = require('http');
const promise = new Promise((resolve, reject) => {
// INVALID OBJECT
//const post_data = JSON.stringify({"something"});
const post_data = JSON.stringify({
something: "something"
});
//ignores SSL
process.env.NODE_TLS_REJECT_UNAUTHORIZED = "0";
var post_request = http.request(post_options, function(res) {
res.on('data', function(chunk) {
body += chunk;
console.log("inside " + JSON.stringify(body));
// DONT RESOLVE HERE, REQUEST IS NOT COMPLETE
//resolve(body);
});
res.on('end', function() {
context.done(body);
//RESOLVE HERE INSTEAD
resolve(body);
});
res.on('error', function(e) {
reject(Error(e.message));
context.fail('error:' + e.message);
});
});
// post the data
post_request.write(post_data);
post_request.end();
});
promise.then((body) => {
console.log("response data " + JSON.stringify(body));
body2 = JSON.parse(body);
callback(delegate(sessionAttributes, intentRequest.currentIntent.slots));
}, (error) => {
console.log('Promise rejected.');
console.log(error.message);
});
}

Using the results of a GET request in Express router

First Node/Express app.
I'm having a hard time wrapping my head around on how to retrieve data from an endpoint and rendering it in the browser.
I have a dataservice.js that gets a JSON object from an endpoint like this:
const http = require('http');
getFinhockeyData = function() {
http.get('http://tilastopalvelu.fi/ih/modules/mod_standings/helper/standings.php?statgroupid=3545', (res) => {
console.log(`Got response: ${res.statusCode}`);
var body = "";
res.on('data', function (chunk) {
body += chunk;
})
res.on('end', function () {
var data = JSON.parse(body);
console.log('data parsed.');
console.log('first team name: ' + data.teams[0].TeamName);
console.log(typeof data);
return data;
})
}).on('error', (e) => {
console.log(`Got error from Finhockey: ${e.message}`);
});
}
module.exports.getFinhockeyData = getFinhockeyData;
Up until now things work and the data object can be console.logged and its content is usable.
The router.js looks currently like this:
'use strict';
const express = require('express');
const async = require('async');
const router = express.Router();
const dataservice = require('./dataservice.js')
router.get('/', function(req, res) {
async.series([
function(callback) {
getFinhockeyData(callback)
}
],
function(err, results) {
console.log('start rendering');
res.render('index', { data: data });
})
});
module.exports = router;
When I run the app and refresh the / route, I can see from the console that the getFinhockeyData is called and the data object's content is available in dataservice.js's console.logs, but the browser window hangs and the res.render part is never reached.
I understand that the rendering should be done only after the endpoint data request has finished (async.series usage), but it seems that I lack a fundamental understanding on how to actually use the result data from the getFinhockeyData function in the main route.
Any advice on this? I'll be happy to provide more info if necessary.
Firstly, doing the request is asynchronous, so you'll have to use either a callback or a promise.
Even the async middleware won't let you just return data from an asynchronous call, it requires a callback, but using native promises seems easier here
const http = require('http');
getFinhockeyData = function() {
return new Promise( (resolve, reject) => {
http.get('http://tilastopalvelu.fi/ih/modules/mod_standings/helper/standings.php?statgroupid=3545', (res) => {
var body = "";
res.on('data', function(chunk) {
body += chunk;
});
res.on('end', function() {
resolve( JSON.parse(body) );
});
}).on('error', reject);
});
}
module.exports.getFinhockeyData = getFinhockeyData;
Also note that you're exporting as a module with a property
module.exports.getFinhockeyData = getFinhockeyData;
when you're going to use that in the routes, you have to use the property
const dataservice = require('./dataservice.js');
router.get('/', function(req, res) {
dataservice.getFinhockeyData().then(function(data) {
res.render('index', { data: JSON.stringify(data) });
}).catch(function(err) {
// epic fail, handle error here
});
});
You are responding to your route call with
res.render('index', { data: data });
But there is no data variable. It should be
res.render('index', { data: results });
Which is the variable where you are storing your data when it comes from the callback
The reason for res.render() not being called is, http requests are async. To get the response a callback must be passed, which you did but forgot to call it in the dataservice.js
This should help...
Change your dataservice.js like the following...
const http = require('http');
getFinhockeyData = function(callback) {
http.get('http://tilastopalvelu.fi/ih/modules/mod_standings/helper/standings.php?statgroupid=3545', (res) => {
console.log(`Got response: ${res.statusCode}`);
var body = "";
res.on('data', function (chunk) {
body += chunk;
})
res.on('end', function () {
var data = JSON.parse(body);
console.log('data parsed.');
console.log('first team name: ' + data.teams[0].TeamName);
console.log(typeof data);
callback(null, data); //returning the data to the callback
})
}).on('error', (e) => {
console.log(`Got error from Finhockey: ${e.message}`);
callback(e, null);
});
}
module.exports.getFinhockeyData = getFinhockeyData;
Change your router.js like the following...
router.get('/', function(req, res) {
async.series([
function(callback) {
getFinhockeyData(callback)
}
],
function(err, results) {
if(err === null){
console.log('start rendering');
res.render('index', { data: results[0] });
}
})
});

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