Need documentation and examples on how to work with synthetic events

[ed-marquez]

Problem

As of v0.79, Mirror nodes now generate contract log events for non-EVM HAPI transactions. These "synthetic" events increase alignment between HTS and ERC standards and facilitate integrations with EVM tools, like The Graph. Events are generated for HAPI transactions like: CryptoTransfer, CryptoApproveAllowance, CryptoDeleteAllowance, TokenMint, TokenWipe, and TokenBurn.

Knowing how to work with these synthetic events can enable new solutions for the ecosystem.

The Problem:

• We haven't documented this important capability.
• We haven't created examples

Solution

• Need to include this information perhaps in core concepts. Open for discussion.

• Example:
  Created this sample that shows how to use ethers.js to listen to synthetic events from HAPI operations done with our SDK (Transfer events)
  https://github.com/ed-marquez/hedera-example-hts-synthetic-events-sdk-ethers
  Feel free to reuse as needed to support any docs or example doc page.

Note: I believe now token operations (done via SDK, Precompile, ERC calls) emit “synthetic” events. Would be good to confirm if there are any HTS operations that do not emit a synthetic event.

cc: @theekrystallee @simi-hedera

Alternatives

No response