How to Get Values From a Url?

WelingtonJr

Hi guys,
I have a url "https://app.sm4rt.com.br/feed/timevalue.json?id=40&apikey=f9cae76090f9f4ba97d5920fd003d3d4", that has a JSON file {"time":"1549978493","value":"137.678"}, then I would like to add this value to a report.

I was trying the function below in a script and in a helper:

function getValue() {
var val;
const https = require('https');
https.get('https://app.sm4rt.com.br/feed/timevalue.json?id=40&apikey=f9cae76090f9f4ba97d5920fd003d3d4', (res) => {

  // A chunk of data has been recieved.
  resp.on('data', (chunk) => {
    data += chunk;  
    val = data.value;
  });

  // The whole response has been received. Print out the result.
  resp.on('end', () => {
    console.log(data.replace(/"/g,""));
  });

}).on("error", (err) => {
  console.log("Error: " + err.message);
});
return val;

}

But, I could not show the value in the report. How should I call this function in the template?

Could you help me with this question?

Thank you for your attention

jan_blaha

You probably want to use a jsreport script entity to run your async data fetch.
See the documentation and example
https://jsreport.net/learn/scripts
https://playground.jsreport.net/w/admin/hG7mEoll

WelingtonJr

Sorry, I can not extract that value.
I've tried it in many ways.
Please, can you give me another example besides this:
https://jsreport.net/learn/scripts
https://playground.jsreport.net/w/admin/hG7mEoll
https://playground.jsreport.net/w/anon/dqFUCAtZ
https://playground.jsreport.net/w/admin/tW8CsfTt

WelingtonJr

I was able to make a request of the data with this code below:

async function beforeRender(req, res){
var str = '';
const https = require('https');
https.get('https://app.sm4rt.com.br/feed/timevalue.json?id=40&apikey=f9cae76090f9f4ba97d5920fd003d3d4',
(result) => {
result.on('data', (b) => {
str += b;
console.log('Data :' + JSON.parse(str).value);
});
});
return {row: str};
}

However, I still do not know how to call this variable in main -Template.

bjrmatos

i think you just need

const https = require("https");

async function beforeRender(req, res, done) {
  var str = "";

  https
    .get(
      "https://app.sm4rt.com.br/feed/timevalue.json?id=40&apikey=f9cae76090f9f4ba97d5920fd003d3d4",
      res => {
        // A chunk of data has been recieved.
        resp.on("data", chunk => {
          str += chunk;
        });

        // The whole response has been received. Print out the result.
        resp.on("end", () => {
          try {
            req.data.row = JSON.parse(str)
          } catch (e) {
            done(e)
          }
        });
      }
    )
    .on("error", err => {
      done(err);
    });
}

then you can row in your template, in your previous examples you are not setting the data that you get from api into req.data, that is fundamental thing to do when you want to pass data from script to template

WelingtonJr

Hi guys.
Thank you very much for the tips, you are helping a lot.
however, when I use the script, at the time of generating the PDF, this error occurs

Anyone know what it might be?
And how to solve?

bjrmatos

ah sorry, i forgot to call done one more time in the script, here it is the script updated.

const https = require("https");

async function beforeRender(req, res, done) {
  var str = "";

  https
    .get(
      "https://app.sm4rt.com.br/feed/timevalue.json?id=40&apikey=f9cae76090f9f4ba97d5920fd003d3d4",
      res => {
        // A chunk of data has been recieved.
        resp.on("data", chunk => {
          str += chunk;
        });

        // The whole response has been received. Print out the result.
        resp.on("end", () => {
          try {
            req.data.row = JSON.parse(str)
            done()
          } catch (e) {
            done(e)
          }
        });
      }
    )
    .on("error", err => {
      done(err);
    });
}

WelingtonJr

Thank you, but the error continued.
I thought could be my server but, I tested in the Invoice example of the Playground and also gave a timeout.
Do you have any more idea what could be?
I really do not know how to solve this error.

WelingtonJr

I got it.
async function beforeRender(req, res, done) {
var str = "";

https
.get(
"https://app.sm4rt.com.br/feed/timevalue.json?id=40&apikey=f9cae76090f9f4ba97d5920fd003d3d4",
res => {

is resp => {

WelingtonJr

Thank you very very much for the help Boris.
Can I ask you one more favor?
Could you help me call this data in the Invoice-template?

bjrmatos

you just need to use call the data using the syntax of the template engine you are using (usually Handlebars), for example if the response contains some attribute named "foo" and you are exposing the response of http request as row, then you just need to put in your template {{row.foo}} if you want to print the content

WelingtonJr

It worked.
Thank you very much, once again.