Axios set Content-Length manually, nodeJS

Question

Is there a way to send a post request in nodeJS and specify th content-length.

I tried (using axios):

let data = `Some text data...........`;

let form = await Axios.post(
    "url.......",
    data,
    {
        headers: {
            Authentication: "token.....",
            "Content-Type": "multipart/form-data; boundary=c9236fb18bed42c49590f58f8cc327e3",
            //set content-length manually 
            "Content-Length": "268"
        }
    }
).catch(e => e);

It doesn't work, the length is set automatically to a value other then the one I pass.

I am using axios but open to using any other way to post from nodeJS.

why do you need to do that? this setting is populated automattically. — Ashish Modi, Jan 28 '20 at 18:51
@Ashish Modi I was having issues and was trying to debug, I actually solved my issue without setting the content-length manually. — Shmili Breuer, Jan 28 '20 at 18:53
this is what `got` doc'n says - The content-length header will be automatically set if body is a string / Buffer / fs.createReadStream instance / form-data instance, and content-length and transfer-encoding are not manually set in options.headers. — Ashish Modi, Jan 28 '20 at 18:53

Dawid Piechota · Answer 1 · 2022-10-11T08:57:05.567

5

I can't add a comment because of low reputation, but part of Sandeep Patel's answer regarding Axios is outdated. You can set Content-Length manually. Axios will not override Content-Length if content-length header is present:

// Add Content-Length header if data exists
  if (!headerNames['content-length']) {
    headers['Content-Length'] = data.length;
  }

Source: https://github.com/axios/axios/blob/main/lib/adapters/http.js#L209-L213

So in your case it would be:

let data = `Some text data...`;

let form = await Axios.post(
    "url...",
    data,
    {
        headers: {
            Authentication: "token....",
            "Content-Type": "contentType...",
            //set content-length manually 
            "Content-Length": "268",
            "content-length": "268"
        }
    }
).catch(e => e);

edited Oct 11 '22 at 08:57

answered Mar 01 '22 at 10:48

Dawid Piechota

51
1
5

Notice the difference in upper case / lower case: Axios sets `Content-Length` (upper case) if there is no `content-length` (lower case). So you set a `Content-Length` (upper case), as you did in your example, it might still be overwritten by axios. – kca Jul 27 '22 at 12:14
@kca At the time of writing my answer I did some testing, and Axios did not overwrite the `Content-Length` – Dawid Piechota Jul 27 '22 at 15:44
Sorry, "as you did in your example" was wrong here: I didn't mean _your_ example Dawid Piechota, I meant the example in the question by Shmili Breuer. – kca Jul 28 '22 at 07:18

Sandeep Patel · Answer 2 · 2020-01-29T06:01:40.653

In Axios, If data is present it will set length calculated from data, so even if you pass header content-length, it will be overridden by code:

Check this out for more details: https://github.com/axios/axios/blob/master/lib/adapters/http.js

Using http or https module you can do:

const https = require('https')

const data = JSON.stringify({
  key:values
})

const options = {
  hostname: 'example.com',
  port: 443,
  path: '/testpath',
  method: 'POST',
  headers: {
    'Content-Type': 'application/json',
    'Content-Length': data.length
  }
}
const req = https.request(options, (res) => {
  console.log(`statusCode: ${res.statusCode}`)

  res.on('data', (d) => {
    process.stdout.write(d)
  })
})

req.on('error', (error) => {
  console.error(error)
})

req.write(data)
req.end()

Axios set Content-Length manually, nodeJS

2 Answers2

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