TAP Migration Guide
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Learn about The Graph’s new payment system, Timeline Aggregation Protocol, TAP. This system provides fast, efficient microtransactions with minimized trust.
is a drop-in replacement to the Scalar payment system currently in place. It provides the following key features:
- Efficiently handles micropayments.
- Adds a layer of consolidations to on-chain transactions and costs.
- Allows Indexers control of receipts and payments, guaranteeing payment for queries.
- It enables decentralized, trustless gateways and improves
indexer-service
performance for multiple senders.
TAP allows a sender to make multiple payments to a receiver, TAP Receipts, which aggregates these payments into a single payment, a Receipt Aggregate Voucher, also known as a RAV. This aggregated payment can then be verified on the blockchain, reducing the number of transactions and simplifying the payment process.
For each query, the gateway will send you a signed receipt
that is stored on your database. Then, these queries will be aggregated by a tap-agent
through a request. Afterwards, you’ll receive a RAV. You can update a RAV by sending it with newer receipts and this will generate a new RAV with an increased value.
-
It’s money that is waiting to be sent to the blockchain.
-
It will continue to send requests to aggregate and ensure that the total value of non-aggregated receipts does not exceed the
amount willing to lose
. -
Each RAV can be redeemed once in the contracts, which is why they are sent after the allocation is closed.
As long as you run tap-agent
and indexer-agent
, everything will be executed automatically. The following provides a detailed breakdown of the process:
An Indexer closes allocation.
<recently-closed-allocation-buffer> period, tap-agent
takes all pending receipts for that specific allocation and requests an aggregation into a RAV, marking it aslast
.indexer-agent
takes all the last RAVS and sends redeem requests to the blockchain, which will update the value ofredeem_at
.During the
<finality-time>
period,indexer-agent
monitors if the blockchain has any reorganizations that revert the transaction.- If it was reverted, the RAV is resent to the blockchain. If it was not reverted, it gets marked as
final
.
- If it was reverted, the RAV is resent to the blockchain. If it was not reverted, it gets marked as
Contract | Arbitrum Sepolia (421614) | Arbitrum Mainnet (42161) |
---|---|---|
TAP Verifier | 0xfC24cE7a4428A6B89B52645243662A02BA734ECF | 0x33f9E93266ce0E108fc85DdE2f71dab555A0F05a |
AllocationIDTracker | 0xAaC28a10d707bbc6e02029f1bfDAEB5084b2aD11 | 0x5B2F33d7Ca6Ec88f5586f2528f58c20843D9FE7c |
Escrow | 0x1e4dC4f9F95E102635D8F7ED71c5CdbFa20e2d02 | 0x8f477709eF277d4A880801D01A140a9CF88bA0d3 |
Component | Edge and Node Mainnet (Arbitrum Sepolia) | Edge and Node Testnet (Aribtrum Mainnet) |
---|---|---|
Sender | 0xDDE4cfFd3D9052A9cb618fC05a1Cd02be1f2F467 | 0xC3dDf37906724732FfD748057FEBe23379b0710D |
Signers | 0xfF4B7A5EfD00Ff2EC3518D4F250A27e4c29A2211 | 0xFb142dE83E261e43a81e9ACEADd1c66A0DB121FE |
Aggregator | https://tap-aggregator.network.thegraph.com | https://tap-aggregator.testnet.thegraph.com |
In addition to the typical requirements to run an indexer, you’ll need a tap-escrow-subgraph
endpoint to query TAP updates. You can use The Graph Network to query or host yourself on your graph-node
.
Note: indexer-agent
does not currently handle the indexing of this subgraph like it does for the network subgraph deployement. As a result, you have to index it manually.
The required software version can be found .
Indexer Agent
Indexer Service
TAP Agent
Configure Indexer Service and TAP Agent
Configuration is a TOML file shared between
indexer-service
andtap-agent
, supplied with the argument--config /path/to/config.toml
.
For minimal configuration, use the following template:
# You will have to change *all* the values below to match your setup.## Some of the config below are global graph network values, which you can find here:# <https://github.com/graphprotocol/indexer/tree/main/docs/networks>## Pro tip: if you need to load some values from the environment into this config, you# can overwrite with environment variables. For example, the following can be replaced# by [PREFIX]_DATABASE_POSTGRESURL, where PREFIX can be `INDEXER_SERVICE` or `TAP_AGENT`:## [database]# postgres_url = "postgresql://indexer:${POSTGRES_PASSWORD}@postgres:5432/indexer_components_0"[indexer]indexer_address = "0x1111111111111111111111111111111111111111"operator_mnemonic = "celery smart tip orange scare van steel radio dragon joy alarm crane"[database]# The URL of the Postgres database used for the indexer components. The same database# that is used by the `indexer-agent`. It is expected that `indexer-agent` will create# the necessary tables.postgres_url = "postgres://postgres@postgres:5432/postgres"[graph_node]# URL to your graph-node's query endpointquery_url = "<http://graph-node:8000>"# URL to your graph-node's status endpointstatus_url = "<http://graph-node:8000/graphql>"[subgraphs.network]# Query URL for the Graph Network subgraph.query_url = "<http://example.com/network-subgraph>"# Optional, deployment to look for in the local `graph-node`, if locally indexed.# Locally indexing the subgraph is recommended.# NOTE: Use `query_url` or `deployment_id` onlydeployment_id = "Qmaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"[subgraphs.escrow]# Query URL for the Escrow subgraph.query_url = "<http://example.com/network-subgraph>"# Optional, deployment to look for in the local `graph-node`, if locally indexed.# Locally indexing the subgraph is recommended.# NOTE: Use `query_url` or `deployment_id` onlydeployment_id = "Qmaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"[blockchain]# The chain ID of the network that the graph network is running onchain_id = 1337# Contract address of TAP's receipt aggregate voucher (RAV) verifier.receipts_verifier_address = "0x2222222222222222222222222222222222222222"######################################### Specific configurations to tap-agent #########################################[tap]# This is the amount of fees you are willing to risk at any given time. For ex.# if the sender stops supplying RAVs for long enough and the fees exceed this# amount, the indexer-service will stop accepting queries from the sender# until the fees are aggregated.# NOTE: Use strings for decimal values to prevent rounding errors# e.g:# max_amount_willing_to_lose_grt = "0.1"max_amount_willing_to_lose_grt = 20[tap.sender_aggregator_endpoints]# Key-Value of all senders and their aggregator endpoints# This one below is for the E&N testnet gateway for example.0xDDE4cfFd3D9052A9cb618fC05a1Cd02be1f2F467 = "https://tap-aggregator.network.thegraph.com"
Notes:
- Values for
tap.sender_aggregator_endpoints
can be found in the . - Values for
blockchain.receipts_verifier_address
must be used accordingly to the using the appropriate chain id.
Log Level
- You can set the log level by using the
RUST_LOG
environment variable. - It’s recommended that you set it to
RUST_LOG=indexer_tap_agent=debug,info
.
All components expose the port 7300 to be queried by prometheus.
Currently, there is a WIP version of indexer-rs
and tap-agent
that can be found