What is "406-Not Acceptable Response" in HTTP? - json

Question

In my Ruby on Rails application I tried to upload an image through the POSTMAN REST client in Base64 format. When I POST the image I am getting a 406 Not Acceptable Response. When I checked my database, the image was there and was successfully saved.
What is the reason for this error, is there anything I need to specify in my header?
My request:
URL --- http://localhost:3000/exercises.json
Header:
Content-Type - application/json
Raw data:
{
"exercise": {
"subbodypart_ids": [
"1",
"2"
],
"name": "Exercise14"
},
"image_file_name": "Pressurebar Above.jpg",
"image":"******base64 Format*******"
}

Answer 1

Your operation did not fail.
Your backend service is saying that the response type it is returning is not provided in the Accept HTTP header in your Client request.
Ref: http://en.wikipedia.org/wiki/List_of_HTTP_header_fields
Find out the response (content type) returned by Service.
Provide this (content type) in your request Accept header.
http://en.wikipedia.org/wiki/HTTP_status_code -> 406

Answer 2

406 Not Acceptable
The resource identified by the request is only capable of generating response entities which have content characteristics not
acceptable according to the accept headers sent in the request.
406 happens when the server cannot respond with the accept-header specified in the request.
In your case it seems application/json for the response may not be acceptable to the server.

Answer 3

You mentioned you're using Ruby on Rails as a backend. You didn't post the code for the relevant method, but my guess is that it looks something like this:
def create
post = Post.create params[:post]
respond_to do |format|
format.json { render :json => post }
end
end
Change it to:
def create
post = Post.create params[:post])
render :json => post
end
And it will solve your problem. It worked for me :)

Answer 4

"Sometimes" this can mean that the server had an internal error, and wanted to respond with an error message (ex: 500 with JSON payload) but since the request headers didn't say it accepted JSON, it returns a 406 instead. Go figure. (in this case: spring boot webapp).
In which case, your operation did fail. But the failure message was obscured by another.

Answer 5

You can also receive a 406 response when invalid cookies are stored or referenced in the browser - for example, when running a Rails server in Dev mode locally.
If you happened to run two different projects on the same port, the browser might reference a cookie from a different localhost session.
This has happened to me...tripped me up for a minute. Looking in browser > Developer Mode > Network showed it.

Answer 6

const request = require('request');
const headers = {
'Accept': '*/*',
'User-Agent': 'request',
};
const options = {
url: "https://example.com/users/6",
headers: headers
};
request.get(options, (error, response, body) => {
console.log(response.body);
});

Answer 7

Changing header to Accept: */* resolved my issue and make sure you don't have any other Accept Header

Answer 8

In my case, I added:
Content-Type: application/x-www-form-urlencoded
solved my problem completely.

Answer 9

If you are using 'request.js' you might use the following:
var options = {
url: 'localhost',
method: 'GET',
headers:{
Accept: '*/*'
}
}
request(options, function (error, response, body) {
...
})

Answer 10

In my case for a API in .NET-Core, the api is set to work with XML (by default is set to response with JSON), so I add this annotation in my Controller :
[Produces("application/xml")]
public class MyController : ControllerBase {...}
Thank you for putting me on the path !

Answer 11

It could also be due to a firewall blocking the request. In my case the request payload contained string properties - "like %abc%" and ampersand symbol "&" - which caused the firewall to think it is a security risk (eg. a sql injection attack) and it blocked the request. Note here the request does not actually go to the server but is returned at the firewall level itself.
In my case, there were no application server logs generated so I knew that the request did not actually reach the server and was blocked before that. The logs that helped me were Web application firewall (WAF) logs.