I am trying to use Substrate Offchain Worker. I implemented as mentioned here https://github.com/paritytech/polkadot-sdk/tree/master/substrate/frame/examples/offchain-worker.

I am using same sample

 let deadline = sp_io::offchain::timestamp().add(Duration::from_millis(2_000));
        let request =
        let pending = request.deadline(deadline).send().map_err(|_| http::Error::IoError)?;
        let response = pending.try_wait(deadline).map_err(|_| http::Error::DeadlineReached)??;
        if response.code != 200 {
            log::warn!("Unexpected status code: {}", response.code);
            return Err(http::Error::Unknown)

When I start my local parachain node with --offchain-worker always, I get below error after each block production:

Evicting failed runtime instance error=Runtime panicked: Accessing a forbidden API: http_request_start. No: HTTP capability.

This URL https://min-api.cryptocompare.com/data/price?fsym=BTC&tsyms=USD is working fine in my browser.

Can somebody please guide me what I am missing here?

1 Answer 1


You need to allow http requests.


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