Local Event Indexer

The Flow local event indexer is available on github and docker and can be used during development before set up your Graffle projects. It is a trimmed down version of the event indexers on the Projects page within the Graffle management dashboard. https://hub.docker.com/r/graffle/flow-event-processor https://github.com/Graffle/flow-event-processor We recommend using the Docker image and running the local indexer using docker, but you can pull the code from GitHub and debug it in your IDE or run it with docker-compose.


  • FlowNode: MainNet, TestNet, or Emulator. Note: Emulator support is currently limited to running from VS Code.

  • MaximumBlockScanRange: Block size to scan when catching up after falling behind, should normally be set to 200.

  • WebhookUrl: Your url which will receive POST requests containing your processed events.

  • EventId: Flow event Id of the event type you want to process. ex: A.c1e4f4f4c4257510.Market.MomentPurchased

  • Verbose: Log found events to the console when posting to WebhookUrl.

  • HMACToken: Base-64 encoded string for HMAC authentication headers.


docker pull graffle/flow-event-processor


docker run -e "FlowNode=TestNet" -e "WebhookUrl=url" -e "EventId=A.c1e4f4f4c4257510.TopShotMarketV3.MomentPurchased" graffle/flow-event-processor


docker run -e "FlowNode=MainNet" -e "WebhookUrl=url" -e "EventId=A.c1e4f4f4c4257510.TopShotMarketV3.MomentPurchased" graffle/flow-event-processor

Note: When using the HMAC variable to set a token, this application always adds the following headers to the request. x-graffle-company-id: 00000000-0000-0000-0000-000000000000 x-graffle-project-id: 00000000-0000-0000-0000-000000000000 See "Securing Indexer Webhooks" for information about decoding/validating HMAC auth headers.


Create a .env.local file in the root of your repository, next to docker-compose.yml:

WEBHOOKURL=https://<your url>
HMACTOKEN=[base64 string]

Open a terminal window in the root of your repository and run one of the following:

 docker-compose build test_net_graffle_flow_event_processor
 docker-compose --env-file .\.env.local up test_net_graffle_flow_event_processor
 docker-compose build main_net_graffle_flow_event_processor
 docker-compose --env-file .\.env.local up main_net_graffle_flow_event_processor

for test net or main net event processing.

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