fetch merges multiple "set-cookie" headers into one string

How-to Discussions
1

There are three separate Set-Cookie in the response header. Each one of them has different key-value pairs in it.
However, when I do response.headers.get('Set-Cookie') that merges all three Set-Cookie values into one big string and I can’t parse them by ; anymore.

fetch(url, {
    headers: {
      'Content-Type': 'application/json'
    },
    cache: 'no-cache'
  }).
  then(response => {
    headers = response.headers.get('Set-Cookie')
    console.log(headers)
    return response.json()
  })

This could be a pure javascript error but I’m not sure cause I can’t iterate through response.headers. It returns fuse objects.

2

Please post a complete reproduction that one could run. Unfortunately there’s not much we can help with, because we don’t know what headers your url there returns.

I added this line in the response block:

console.log(JSON.stringify(response.headers));

and tested with a random JSON API. I see that the headers are just a plain object, and I do not think that JSON objects allow several properties have the same name. You’re likely mixing something up.

3

Hi,

Please find it below. As you can see, there is only one “Set-Cookie” in the header and the values are merged. My-service and AWSELB should have separated by ; .

{  
   "map":{  
      "expires":[  
         "Thu, 01 Jan 1970 00:00:00 GMT"
      ],
      "x-android-selected-protocol":[  
         "http/1.1"
      ],
      "set-cookie":[  
         "JSESSIONID=node01pz39az7dsyunkzwr36xdbnpt42.node0;Path=/;My-service=6#06b8c158-86fe-446d-938e-2dc32be30589AWSELB=39C1CB2504672352592767B2CC8E871333B8A132A58C25955239B29FE2F6A83C8B7186F218837203C81AC91FC70814AFC4B05C685203728161BCE5B068789BED868EE35D81;PATH=/"
      ],
      "connection":[  
         "keep-alive"
      ],
      "x-android-response-source":[  
         "CONDITIONAL_CACHE 200"
      ],
      "x-android-sent-millis":[  
         "1504625017274"
      ],
      "content-type":[  
         "application/json"
      ],
      "cache-control":[  
         "no-cache=\"set-cookie\""
      ],
      "date":[  
         "Tue, 05 Sep 2017 15:23:35 GMT"
      ],
      "content-length":[  
         "108"
      ],
      "server":[  
         "nginx/1.10.3 (Ubuntu)"
      ],
      "null":[  
         "HTTP/1.1 200 OK"
      ],
      "x-android-received-millis":[  
         "1504625017311"
      ]
   }
4

Have you tried debugging what cookie string your backend sends? Is the “merging” behaviour specific to Fuse, or does, for example, a browser receive the same?

And again, please provide a complete reproduction that we could run.