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1 change: 1 addition & 0 deletions pages/entropy/_meta.json
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},

"generate-random-numbers": "Generate Random Numbers",
"debug-callback-failures": "Debug Callback Failures",

"-- Reference Material": {
"title": "Reference Material",
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91 changes: 91 additions & 0 deletions pages/entropy/debug-callback-failures.mdx
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# Debug Callback Failures

This guide explains how to identify and resolve issues with the Entropy callback.
The intended audience for this guide is developers who have made an Entropy random number request, but their application hasn't received a callback.

## Dependencies

This guide uses [Foundry](https://book.getfoundry.sh/getting-started/installation) to submit transactions to the blockchain.
Please install Foundry before continuing.

## Run the Callback

Developers can run the Entropy callback themselves to see the reason for the failure.
To run the callback, invoke the `revealWithCallback` function on the Entropy contract on your blockchain.
The function has the following signature:

```solidity
function revealWithCallback(address provider, uint64 sequenceNumber, bytes32 userRandomNumber, bytes32 providerRevelation)
```

This call requires the chain id, contract address and four arguments.
The chain id and contract address can be retrieved from [Contract Addresses](/entropy/contract-addresses).
Export these values as environment variables for later use:

```bash
export CHAIN_ID=blast
export ENTROPY_ADDRESS=0x5744Cbf430D99456a0A8771208b674F27f8EF0Fb
```

Three of the arguments can be retrieved from the request transaction's event logs.
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Shouldn't we give a small explanation here about these arguments?

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I'm trying to stick to the diataxis guideline to avoid explanation in how-to guides. I also think anyone reading this guide will know what these are (because they wrote the code to integrate the software in the first place)

Look at the event logs of the request transaction in a block explorer.
You should see a `RequestedWithCallback` event emitted from the Entropy contract, similar to the one below:

![Example Entropy event logs](../../images/entropy_event_log.png)

Copy the following values from the event into environment variables:

```bash
export PROVIDER=0x52DeaA1c84233F7bb8C8A45baeDE41091c616506
export SEQUENCE_NUMBER=264793
# First row of the "Data" field with a 0x prefix
export USER_RANDOM_NUMBER=0xb1db70cfe95d9e823ac591362921c20eb45f136dbf417362f0a045dc7100519e
```

Next, collect the provider's revelation.
Every provider exposes a URL which allows users to get the provider's revelation for unfulfilled requests.
The URLs for the default providers are as follows:

| Network type | Provider URL |
| ------------ | ---------------------------------------- |
| testnet | `https://fortuna-staging.dourolabs.app/` |
| mainnet | `https://fortuna.dourolabs.app` |

Retrieve the `/v1/chains/$CHAIN_ID/revelations/$SEQUENCE_NUMBER` endpoint from this server:

```bash
curl https://fortuna.dourolabs.app/v1/chains/$CHAIN_ID/revelations/$SEQUENCE_NUMBER
```

This endpoint will return the provider's revelation as a hexadecimal value, such as:

```json
{
"value": {
"encoding": "hex",
"data": "5d4bfa3abeaf15fe8b7771c74c0e3e210096015632831460870bc5374e05d4d8"
}
}
```

Export this value as an environment variable (prefixed with 0x):

```bash
export PROVIDER_REVELATION=0x5d4bfa3abeaf15fe8b7771c74c0e3e210096015632831460870bc5374e05d4d8
```

Finally, submit the transaction to invoke `revealWithCallback`:

```bash
cast send $ENTROPY_ADDRESS 'revealWithCallback(address, uint64, bytes32, bytes32)' $ENTROPY_ADDRESS $SEQUENCE_NUMBER $USER_RANDOM_NUMBER $PROVIDER_REVELATION
```

You may also need to provide the `-r` with an RPC for your chain, plus an additional argument (such as `--private-key`) to specify the wallet to use to sign the transaction.

## Interpeting the Results

If the transaction succeeds, check how much gas the transaction used.
If the gas exceeds the callback gas limit for your chain as shown on [Contract Addresses](/entropy/contract-addresses), please reduce the gas usage to allow the provider to invoke the callback in the future.

If the transaction fails, it typically indicates a failure originating from the implementation of the callback function.
Check your implementation of the `entropyCallback` function to ensure that it does not throw an error when invoked.
8 changes: 3 additions & 5 deletions pages/entropy/generate-random-numbers.mdx
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# Generate Random Numbers

Integrations use a simple one-step on-chain process:

1. **Request** a random number. Send a transaction with a random number that you have generated off-chain and receive a sequence number.

Entropy will callback your contract with the generated random number once the request is fullfilled by the provider.
Integrations simply call an on-chain function to request a random number from Entropy.
This function takes a random number that you have generated off-chain and returns a sequence number.
Entropy will then callback your contract with the generated random number once the request is fullfilled by the provider.
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drive-by simplification of the text here


See [How to Generate Random numbers in EVM dApps](generate-random-numbers/evm.mdx) to integrate your application with Pyth Entropy.
4 changes: 4 additions & 0 deletions pages/entropy/generate-random-numbers/evm.mdx
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Expand Up @@ -95,3 +95,7 @@ function entropyCallback(
```

When the final random number is ready to use, the entropyCallback function will be called by the Entropy contract. This will happen in a separate transaction submitted by the requested provider. The entropyCallback function should be implemented in the same contract that is requesting the random number.

## Additional Resources

If you are having trouble getting the callback to run, please see the guide on how to [Debug Callback Failures](/entropy/debug-callback-failures).
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