indexer-wildcard

name	indexer-wildcard
description	Use when indexing all instances of a contract across all addresses (e.g., all ERC-20 transfers on a chain). Config setup (no address), wildcard handler option, and event.srcAddress.
metadata	{"managed-by":"envio"}

Wildcard Indexing

Index all events matching an event signature across all contract addresses on a chain.

Config (no address = wildcard)

contracts:
  - name: ERC20
    events:
      - event: Transfer(indexed address from, indexed address to, uint256 value)

chains:
  - id: 1
    contracts:
      - name: ERC20
        # No address = wildcard (indexes ALL matching events on the chain)

Handler with wildcard: true

Pass wildcard: true in the options object to indexer.onEvent. Use event.srcAddress to identify which contract emitted the event:

indexer.onEvent(
  {
    contract: "ERC20",
    event: "Transfer",
    wildcard: true,
    fields: { transaction: ["hash"] },
  },
  async ({ event, context }) => {
    const tokenAddress = event.srcAddress; // The actual contract address
    const id = `${event.transaction.hash}-${event.logIndex}`;

    context.Transfer.set({
      id,
      token_id: tokenAddress,
      from: event.params.from,
      to: event.params.to,
      value: event.params.value,
    });
  },
);

Combining with Event Filters (where)

Wildcard indexing produces high event volume. Use where to reduce it — see the indexer-filters skill for object, array, function, and addresses forms.

indexer.onEvent(
  {
    contract: "ERC20",
    event: "Transfer",
    wildcard: true,
    where: { params: { from: ZERO_ADDRESS } },
  },
  async ({ event, context }) => {
    /* ... */
  },
);

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