Deadline: 4th of December 2024 at 5pm GMT

Introduction

• Overview of TAP:
  • It replaces the older Scalar payment system.
  • Key features like efficient micropayments, reduced on-chain transactions, and indexer control over receipts.
  • How it enables decentralised gateways by allowing indexers to accept queries from multiple gateways.
• Ok, but what do we really have to do?
• Update indexer stack so that instead of running indexer-agent and indexer-service from https://github.com/graphprotocol/indexer to running indexer-agent ( https://github.com/graphprotocol/indexer but version 0.21.4 or more recent), replacing indexer-service to run rust version ( https://github.com/graphprotocol/indexer-rs) and new component indexer-tap-agent from ( https://github.com/graphprotocol/indexer-rs).
• Resources:
  • use launchpad-charts/graph-network-indexer if using Kubernetes
  • use staskequid stack if using docker-compose
  • https://thegraph.com/docs/en/tap/

Common Issues and Troubleshooting

• Unaggregated Fees and RAV Requests:

  • Issue: Indexers might see their unaggregated fees plateau, especially if the rav_request_trigger_value is set too low.
  • Explanation: The rav_request_trigger_value determines when the indexer requests a Receipt Aggregate Voucher (RAV) from the sender. If this value is too low, the trigger might not be met frequently enough, causing fees to accumulate without being aggregated.
  • Solution: Update your rav_request_trigger_value which is calculated as max_amount_willing_to_lose_grt / trigger_value_divisor.

• Sender Denial Issues:

  • Issue: Indexers might encounter situations where senders are denied, leading to disruptions in query processing and revenue.
  • Reasons for Denial: Discuss the three primary reasons for sender denial:
    • Sender not listed in tap.sender_aggregator_endpoints.
    • Sender's escrow balance insufficient to cover outstanding fees.
    • Unaggregated fees exceeding the max_fee_per_sender limit.
  • Solutions: Provide specific solutions for each denial reason:
    • Verify the sender is correctly configured in the tap.sender_aggregator_endpoints section.
    • Investigate potential issues with escrow funding and ensure sufficient balance.
    • Review and potentially adjust the max_amount_willing_to_lose_grt setting if unaggregated fees frequently hit the limit.
  • Note!! Indexer tap agent will always start with

  2024-11-13T08:41:31.200776Z ERROR indexer_tap_agent::agent::sender_accounts_manager: There was an error while starting the sender 0xDD6a6f76eb36B873C1C184e8b9b9e762FE216490, denying it. Error: No sender_aggregator_endpoints found for sender 0xDD6a6f76eb36B873C1C184e8b9b9e762FE216490
      at tap-agent/src/agent/sender_accounts_manager.rs:311
      in ractor::actor::Actor with id: "0.0"
  

  for any senders not configured in tap.sender_aggregator_endpoints or via env vars in the format INDEXER_TAP__SENDER_AGGREGATOR_ENDPOINTS__<address>

• collect-receipt-endpoint error on indexer-agent :

{"level":40,"time":1731239677641,"pid":1,"hostname":"graph-network-indexer-agent-0","name":"IndexerAgent","msg":"The option '--collect-receipts-endpoint' is deprecated. Please use the option '--gateway-endpoint' to inform the Gateway base URL."}

• RAV Request Errors:
  • Issue: Errors during RAV requests can disrupt the aggregation process.
  • Error Example: Highlight the error message: "It looks like there are no valid receipts for the RAV request...You can fix this by increasing the rav_request_trigger_value".
  • Explanation: Explain that this error suggests an insufficient rav_request_trigger_value is preventing receipts from being included in the RAV request.
  • Solution: Emphasise the solution provided in the error message – increase the rav_request_trigger_value.

Configuration and Setup

• Software Versions: Required software versions for indexer-agent, indexer-service, and tap-agent.
• Configuration File Walkthrough:
  • Shared Configuration: indexer-service and tap-agent share a common TOML configuration file but environment variables can be used as well as a replacement
• Blockchain Addresses and Endpoints:
  • Make sure to use the correct contract addresses, gateway endpoints, and chain IDs.

Monitoring and Debugging

• Log Level Configuration: To set the RUST_LOG environment variable for appropriate logging use RUST_LOG=indexer_tap_agent=debug,info.
• Metrics and Grafana Dashboard:
  • Metrics Endpoint: All components expose metrics on port 7300 for Prometheus.
  • Grafana Dashboard: https://github.com/graphprotocol/indexer-rs/blob/main/docs/dashboard.json