Sending data from post request to get request in nodejs - javascript

Hey guys just started with nodejs and express so i came up with the situation where i want to send my data to my GET req from my POST req.Here is the code below for you to understand
app.post('/run-time',(req,res)=>{
const stoptime=req.body.stop
const plannedtime=req.body.planned
const runtime=plannedtime-stoptime
res.redirect('/run-time')
})
this is my POST req where i fetched the values from the form and then calculated the 'runtime' now then i have to redirect to specific GET route
app.get('/run-time',(req,res)=>{
})
so what i want is send the 'runtime' variable calulated in my POST req to my GET req here ..how can i do this ?

I've never been use that way But I think you can use querystring
querystring can contains data in url.
app.post('/run-time',(req,res)=>{
const stoptime=req.body.stop
const plannedtime=req.body.planned
const runtime=plannedtime-stoptime
res.redirect(`/run-time?runtime={runtime}`);
})
app.get('/run-time',(req,res)=>{
var runtime = req.query.runtime;
//~
})
I think that way can be your solution.
But you have to change your code because It is not used like this.
Maybe many solution is.

Related

Sending an array with axios.get as params is undefined

I am making a get request with additional params options, since I am using that request on a filter, so the params are filters for what to get back:
const res = await axios.get("http://localhots:3000/getsomedata", {
params: {
firstFilter: someObject,
secondFilter: [someOtherObject, someOtherObject]
}
});
The request goes through just fine, on the other end, when I console.log(req.query); I see the following:
{
firstFilter: 'someObject',
'secondFilter[]': ['{someOtherObject}', '{someOtherObject}'],
}
If I do req.query.firstFilter that works just fine, but req.query.secondFilter does not work and in order for me to get the data, I have to do it with req.query["secondFilter[]"], is there a way to avoid this and be able to get my array of data with req.query.secondFilter?
My workaround for now is to do:
const filter = {
firstFilter: req.query.firstFilter,
secondFilter: req.query["secondFilter[]"]
}
And it works of course, but I don't like it, I am for sure missing something.
Some tools for parsing query strings expect arrays of data to be encoded as array_name=1&array_name=2.
This could be a problem if you have one or more items because it might be an array or might be a string.
To avoid that problem PHP required arrays of data to be encoded as array_name[]=1&array_name[]=2 and would discard all but the last item if you left the [] out (so you'd always get a string).
A lot of client libraries that generated data for submission over HTTP decided to do so in a way that was compatible with PHP (largely because PHP was and is very common).
So you need to either:
Change the backend to be able to parse PHP style
Change your call to axios so it doesn't generate PHP style
Backend
The specifics depend what backend you are using, but it looks like you might be using Express.js.
See the settings.
You can turn on Extended (PHP-style) query parsing by setting it to "extended" (although that is the default)
const app = express()
app.set("query parser", "extended");
Frontend
The axios documentation says:
// `paramsSerializer` is an optional function in charge of serializing `params`
// (e.g. https://www.npmjs.com/package/qs, http://api.jquery.com/jquery.param/)
paramsSerializer: function (params) {
return Qs.stringify(params, {arrayFormat: 'brackets'})
},
So you can override that
const res = await axios.get("http://localhots:3000/getsomedata", {
params: {
firstFilter: someObject,
secondFilter: [someOtherObject, someOtherObject]
},
paramsSerializer: (params) => Qs.stringify(params, {arrayFormat: 'repeat'})
});
My example requires the qs module
This has to do with params not being serialized correctly for HTTP GET method. Remember that GET has no "body" params similar to POST, it is a text URL.
For more information I refer to this answer, which provides more detailed info with code snippets.

js function calling an api doesn't respond with expected values

I am trying to collect all the market pairs from a crypto exchange using its API, but I'm not sure how to select the proper line in the JSON object as it does not seem to work.
the api : https://ftx.com/api/markets
my code :
requests.js
import axios from 'axios';
import parsers from './parsers';
async function ftxMarkets() {
const ftxResponse = await axios.get('https://ftx.com/api/markets');
return parsers.ftxMarkets(ftxResponse.data);
}
parsers.js
function ftxMarkets(data) {
const [ftxMarketPairs] = data;
let ftxPairs = data.map(d => d.name );
console.log(ftxPairs);
};
I'm not sure about d.name in the parsers.js file, but I tried with another exchange with the same code, changing just that part and it worked, so I guess that's where the problem comes from, although can't be sure and I don't know by what to replace it.
Thanks
I ran the api call and after looking at the response I see a result key with the list of all crypto data. So I am guessing it'll work if you call the parser with the result object like this
return parsers.ftxMarkets(ftxResponse.result);
// try parsers.ftxMarkets(ftxResponse.data.result) if the above one doesnt work
and then in the parser it should work normally
function ftxMarkets(data) {
let ftxPairs = data.map(d => d.name );
console.log(ftxPairs);
};
Update:
Since fxtResponse.data.result works. Your issue should be a CORS issue and to fix that there are two options.
CORS plugin in web browser(not recommended in production)
Proxy it through a server. By requesting the resource through a proxy - The simplest way, what you can do is, write a small node server (or if you already have a back-end associate it with your front-end you can use it) which does the request for the 3rd party API and sends back the response. And in that server response now you can allow cross-origin header.
For 2 If you already have a nodeJs server. You can use CORs Npm package and call the third party api from the server and serve the request to the front end with CORS enabled.

Save data from GET request as variable

I've got a simple axios GET request that is working with Azure directline 3.0. The GET request pulls back data and shows it in the console (as seen in the picture).
The data I want to save into a variable is the conversationId. I then want to use this variable with Axios Post in another JS file to post as part of the link e.g. let URL = "https://directline.botframework.com/v3/directline/conversations/"+convID"/activities". With convID being the variable I wish to create. Right now I am manually changing the convID with the new conversation ID, but I want to create a variable so I can place it in the post javascript file so it is automatic.enter image description here
There are various ways you can solve this problem. Easiest one being, exposing the data on a shared object window.convID = convID and then accessing it wherever required.
You could also look to make singleton objects, which can be instantiated only once and hence will share it's variables across the lifespan of the application.
axios.get(/* URL */).then(res => {
window.convID = res.data.conversationId;
});
You can save that variable value in LocalStorage. Something like this:
let routeToYourApi = '/api/conversations'; // or something like this...
axios.get(routeToYourApi).then((response) => {
let conversationId = response.data.conversationId; // not sure if data object from your image is directly nested inside response that you get from server, but you get the idea...
window.localStorage.setItem("convId", conversationId);
}) // here you can fetch your conversation id
Than you can access it anywhere in your app:
let conversationId = window.localStorage.getItem("convId");
... and eventually remove it from local storage:
window.localStorage.removeItem("convId")
Hope this will help you!

Express with JSON Data Control

I use lowDB dependency to control the JSON Data with Express and actually it works. But there is a bug and I cannot find how to solve it.
I create /create page to add information in JSON file and it contains 4 form and submit button.
And In express I code like this. each forms data will save it in variable and push with lowdb module.
router.post('/post', function (req, res) {
let pjName = req.body.projectName;
let pjURL = req.body.projectURL;
let pjtExplanation = req.body.projectExplanation;
let pjImgURL = req.body.projectImgURL;
console.log(pjName);
db.get('project').push({
name: pjName,
url: pjURL,
explanation: pjtExplanation,
imgurl: pjImgURL
}).write();
console.log(db.get('project'));
console.log(db.get('project').value());
res.redirect('/');
})
And it works well. But when I modify the JSON file myself (ex. reset the JSON file) and execute again. It shows the data that I reset before. I think in this app somewhere saves the all data and show save it in array again.
And When I shutdown the app in CMD and execute again, the Array is initialized.
As you may already know the lowdb persist the data into your secondary memory (hdd), and may return a promise depending on your environment when you call write method.As mentioned in the doc
Persists database using adapter.write (depending on the adapter, may return a promise).
So the data may be still getting write when you read them, so the old data is queried. Try this,
db.get('project').push({
name: pjName,
url: pjURL,
explanation: pjtExplanation,
imgurl: pjImgURL
}).write().then(() => {
console.log(db.get('project'));
console.log(db.get('project').value());
});

Node JS sending data via URL

Recently i started programming with Node JS and found it an amazing replacement for php . In php i used to send get requests with Data in the url .
Something like : http://sample.com/public.php?x=helloworld
How to perform something like this in Node JS or is there a better way to send data to node unlike using the url in the above case .
Also , I have noticed that in some cases like stackoverflow , queries are different and dont include the file name
like /public?= instead of /public.php?=
How is this achieved , i always thought this was something related to REST . Also , if you have the answer you might as well guide me if it could be done with Node and a few sources to learn could be of help too .
the most regular way to use REST api
req.query
// GET /search?q=foo+bar
req.query.q
// => "foo bar"
// GET /phone?order=desc&phone[color]=black&shoe[type]=apple
req.query.order
// => "desc"
req.query.phone.color
// => "black"
req.params
// GET /user/william
req.params.name
// => "william"
req.body(for form data)
// POST /login
req.body.username
// => "william"
req.body.password
// => "xxxxxx"
You'll probably be much better off using a pre-existing module as your web server. You can set one up manually, but you have to know about a lot of potential edge cases and really understand web servers. Most people in node use express. In node, as in any server-side language, you can pass data around in a few ways. The query string is one. You can also put some parameters directly in the url (like "/users/12" where 12 is a user id). Depending on the type of request, you can put data in the body of the request. You can also pass cookies. These are not node-specific. Explaining how express works in a post like this would be crazy, so I'll just give you a short example of a what a route handler matching your example route might look like:
var express = require('express');
var app = express();
app.get('/public', function(req, res, next) {
// Get the value from the query string. Express makes the query
// available as an object on the request parameter.
var x = req.query.x;
// Execute your main logic
doSomethingWithX(x);
// Send a response
res.status(200).json({ foo: 'bar' });
});

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