A squid that saves USDC Transfers to CSV files on a S3-compatible service

This tiny blockchain indexer scrapes Transfer events emitted by the USDC contract and saves the data in a file-based dataset located at the Filebase S3-compatible data storage service. It is built with the Subsquid framework, hence the term "squid".

The squid uses @subsquid/file-store, @subsquid/file-store-csv and @subsquid/file-store-s3 packages to store the dataset. S3 connection parameters are partially hardcoded to illustrate how they can be supplied programmatically.

The files are stored in a simple CSV format, but a more performant Apache Parquet format is supported as well. See the documentation page and this example for more info.

Dependencies: NodeJS, Squid CLI.

To see it in action, clone the repository and install dependencies:

$ git clone https://github.com/subsquid-labs/file-store-s3-example
$ cd file-store-s3-example/
$ npm i

Next, create a subsquid-testing-bucket bucket at your Filebase account and set your authentication credentials in .env:

S3_ACCESS_KEY_ID=myKeyId
S3_SECRET_ACCESS_KEY=mySecretAccessKey

Finally, spin up a processor, a process that ingests the data from the Ethereum Archive:

$ sqd process

You should see a transfers-data folder populated with indexer data appear in the bucket in a bit.