IPFS and CORS

This subject jumps from time to time.

We will teach you, how to setup your IPFS API to accept (or deny) CORS requests, and how to test it.

Configuration of CORS

You can do it from the console before starting your IPFS daemon:

ipfs init
ipfs config Addresses.API /ip4/0.0.0.0/tcp/5001
ipfs config --json API.HTTPHeaders.Access-Control-Allow-Origin '["http://infurarocks.com"]'
ipfs config --json API.HTTPHeaders.Access-Control-Allow-Methods '["PUT", "GET", "POST"]'

If you want to accept all domains, replace http://infurarocks.com with *.

Init your IPFS daemon

ipfs daemon

Testing

Hey @infura is CORS in IPFS working?

Using curl, you can answer yourself that question:

To illustrate the example, we will suppose that the API only accept calls to http://infurarocks.com

# Bad request example
# Replace the address and port of the daemon conveniently

curl -H "Origin: http://not-infura.com" \
-H "Access-Control-Request-Method: POST" \
-H "Access-Control-Request-Headers: X-Requested-With" \
--verbose \
http://0.0.0.0:5001/api/v0/swarm/peers; echo

Will give you something like

*   Trying 0.0.0.0...
* Connected to 0.0.0.0 (127.0.0.1) port 5001 (#0)
> GET /api/v0/swarm/peers HTTP/1.1
> Host: 0.0.0.0:5001
> User-Agent: curl/7.50.1
> Accept: */*
> Origin: http://not-infura.com
> Access-Control-Request-Method: POST
> Access-Control-Request-Headers: X-Requested-With
>
< HTTP/1.1 403 Forbidden
< Date: Mon, 12 Sep 2016 07:16:46 GMT
< Content-Length: 15
< Content-Type: text/plain; charset=utf-8
<
* Connection #0 to host 0.0.0.0 left intact
403 - Forbidden

Now, for a proper domain (http://infurarocks.com):

# Good request example
# Replace the address and port of the daemon conveniently

curl -H "Origin: http://infurarocks.com" \
-H "Access-Control-Request-Method: POST" \
-H "Access-Control-Request-Headers: X-Requested-With" \
--verbose \
http://0.0.0.0:5001/api/v0/swarm/peers; echo

You will get

> GET /api/v0/swarm/peers HTTP/1.1
> Host: 0.0.0.0:5001
> User-Agent: curl/7.50.1
> Accept: */*
> Origin: http://infurarocks.com
> Access-Control-Request-Method: POST
> Access-Control-Request-Headers: X-Requested-With
>
< HTTP/1.1 200 OK
< Access-Control-Allow-Headers: X-Stream-Output, X-Chunked-Output, X-Content-Length
< Access-Control-Allow-Origin: http://infurarocks.com
< Access-Control-Expose-Headers: X-Stream-Output, X-Chunked-Output, X-Content-Length
< Content-Type: application/json
< Server: go-ipfs/0.4.2
< Trailer: X-Stream-Error
< Vary: Origin
< Date: Mon, 12 Sep 2016 07:19:27 GMT
< Transfer-Encoding: chunked
<
{"Strings":["/ip4/104.131.131.82/tcp/4001/ipfs/QmaCpDMGvV2BGHeYERUEnRQAwe3N8SzbUtfsmvsqQLuvuJ","/ip4/104.236.179.241/tcp/4001/ipfs/QmSoLPppuBtQSGwKDZT2M73ULpjvfd3aZ6ha4oFGL1KrGM","/ip4/104.236.76.40/tcp/4001/ipfs/QmSoLV4Bbm51jM9C4gDYZQ9Cy3U6aXMJDAbzgu2fzaDs64","/ip4/107.170.183.188/tcp/4001/ipfs/QmUj1nhB7j5cACy9gA9yEcxNJsHTt4LKNgw1RhuiJM9hXU","/ip4/139.59.242.36/tcp/4001/ipfs/QmWbHo1ddCjPx945BkpKjp1ap6SBzknC8GNCRGs1QNU8up","/ip4/162.243.248.213/tcp/4001/ipfs/QmSoLueR4xBeUbY9WZ9xGUUxunbKWcrNFTDAadQJmocnWm","/ip4/163.172.144.207/tcp/4001/ipfs/QmPHYb63UN3vPMTDNqGJ1PQGzhxUrdaQjEGzvwzR7QTqnJ","/ip4/169.47.12.2/tcp/4001/ipfs/QmetLDZ55on5sGQiDUxNCFaXmWY8Pw24SA2HF5o5v9sotd","/ip4/178.62.107.36/tcp/4001/ipfs/QmNQsK1Tnhe2Uh2t9s49MJjrz7wgPHj4VyrZzjRe8dj7KQ","/ip4/178.62.158.247/tcp/4001/ipfs/QmSoLer265NRgSp2LA3dPaeykiS1J6DifTC88f5uVQKNAd","/ip4/178.62.61.185/tcp/4001/ipfs/QmSoLMeWqB7YGVLJN3pNLQpmmEk35v6wYtsMGLzSr5QBU3","/ip4/193.73.242.7/tcp/4001/ipfs/QmQCeB5Sn4uw88HCG3nScHu1Qf4w5GTooSheAYHPpEMfaX","/ip4/195.154.14.157/tcp/4001/ipfs/QmYqXsApqs4BwU1eLBDMjV9XYeP4XCgjZgw2UYrJh1GAK3","/ip4/212.71.255.148/tcp/4001/ipfs/QmX4bukpF7jFEnyrAEZtsUchCbaCxsu2GEBH4GoZwfgASd","/ip4/51.254.25.17/tcp/4002/ipfs/QmdKbeXoXnMbPDfLsAFPGZDJ41bQuRNKALQSydJ66k1FfH","/ip4/52.204.245.162/tcp/4001/ipfs/QmZyJVCp2in8YfQrcj6Ahyyw3CwNKHZZbc7nMvVQov19m5","/ip4/63.152.95.125/tcp/4001/ipfs/Qme9kKrtmLQHy8RGYbVZQEsg1GC7DTgrTkmupR1s8Y4a52","/ip4/65.19.134.242/udp/4001/utp/ipfs/QmTtyvp3nBk6v7aPdNjGrm7MNwtGDpZzjycYpFD8Cijtb1","/ip4/66.11.119.165/tcp/4001/ipfs/QmZ5qTkNvvZ5eFq9T4dcCEK7kX8L7iysYEpvQmij9vokGE","/ip4/84.22.115.40/tcp/4001/ipfs/QmfPZcnVAEjXABiA7StETRUKkS8FzNt968Z8HynbJR7oci"]}
* Connection #0 to host 0.0.0.0 left intact