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Stream USDC transfers from Portal to logger. Use case: Basic data streaming with query builder. 
import { createTarget } from "@subsquid/pipes";
import { evmPortalSource, EvmQueryBuilder } from "@subsquid/pipes/evm";

async function main() {
const queryBuilder = new EvmQueryBuilder()
  .addFields({
    block: { number: true, hash: true },
    log: { address: true, topics: true, data: true, transactionHash: true },
  })
  .addLog({
    request: {
      address: ["0xa0b86991c6218b36c1d19d4a2e9eb0ce3606eb48"], // USDC
      topic0: [
        "0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef",
      ], // Transfer
    },
    range: { from: 20000000, to: 20000000 },
  });

const source = evmPortalSource({
  portal: "https://portal.sqd.dev/datasets/ethereum-mainnet",
  query: queryBuilder,
});

const target = createTarget({
  write: async ({ logger, read }) => {
    for await (const { data } of read()) {
      logger.info(data, "data");
    }
  },
});

await source.pipeTo(target);
}

void main();
For better type safety and developer experience, use evmDecoder with ABIs generated by @subsquid/evm-typegen instead of manually specifying topic0 hashes. See the Event Decoding guide for a typed approach.