How can I get a json file hosted on the IC with JS in the browser? [Anonymous Dev Question]

Developers
1

My Intent

Ahoy ICP devs!

Within the internal DFINITY team channels (OpenChat, Signal, Slack), I have seen some developer-centric technical questions which I think would be great for the wider developer forum to see. I think they can be helpful to share the question/answer so future folks looking for answers can find them.

This is my first attempt at doing this, and if people do not find it useful, I will stop :slight_smile:

Let me know what you think. Thanks!

Question

How can I get a json file hosted on the IC with JS in the browser?

fetch isn’t working because I get CORS issues. Can they be set in the canister? Or should I use agent-js somehow? I believe it’s a normal CORS issue, but with IC maybe I’m missing something :sweat_smile:

Thanks!

Answer

you can configure the asset canister to return custom headers, i.e., you can configure

*Access-Control-Allow-Origin: **

there and you should be able to fetch it from a different origin.

8 Likes
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Configure it where? I didn’t know there was a config file for the standard Asset canister.

3

.ic-assets.json

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Ideally everyone asks all technical questions in the open forum, so that their answers are also searchable and in the open forum.

Anonymous posting can probably be enabled if necessary.

5

I agree.

I do think its reasonable people post things in internal channels because they expect faster reply, but I think moving more and more openly is good.

To be honest, I anonymized the question for non-obvious reason:

  1. I removed information about the problem that I thought the original author may not want in a public format.

  2. I anomymized also because I see a whole lot of internal slack questions which i think would help to be public, and anomyzing would make it easier to get the blessing to post it. I want to do LOTS more.

1 Like