Slashed Indexer

The indexer for Slashed. Looks for slashing events using an archive node RPC, stores the events in database.

Usage

CHAIN_NAME=kujira \
TENDERMINT_RPC_URL=https://archive.kujira.network \
npm run dev

Add new chain

Add the new chain_name to src/chains.ts and start the indexer with CHAIN_NAME and TENDERMINT_RPC_URL.

On the infra side update terraform/variables.tf with the new chain_name. We also need to create a new slashed-chain_name-tendermint-rpc entry in GCP Secret Manager.

Local database

Start the local database with:

npm run supabase start

DB backup & restore

Backup everything:

docker run -it --env=PGPASSWORD --rm postgres \
pg_dump -h db.decrqnsfynvibkranfzq.supabase.co -p 5432 -d postgres -U postgres \
> backup_all.sql

Backup data only on a subset of tables:

docker run -it --env=PGPASSWORD --rm postgres \
pg_dump -h db.decrqnsfynvibkranfzq.supabase.co -p 5432 -d postgres -U postgres \
--data-only --table blocks --table chains --table slashing_events --table sync_statuses --table validators \
> backup_data.sql

Or using pg_dump custom format:

docker run -it --rm --env=PGPASSWORD --volume $(pwd)/dump:/tmp/dump postgres \
pg_dump -h db.decrqnsfynvibkranfzq.supabase.co -p 5432 -d postgres -U postgres \
-Fc --table blocks --table chains --table slashing_events --table sync_statuses --table validators \
--file /tmp/dump/backup_data.dump

Restore:

cat backup_data.sql | \
docker run -i --env=PGPASSWORD --add-host=host.docker.internal:host-gateway \
--rm postgres psql -h host.docker.internal -p 54322 -d postgres -U postgres

Restore from custom format:

cat dump/backup_data.dump | \
docker run -i --env=PGPASSWORD --add-host=host.docker.internal:host-gateway \
--rm postgres pg_restore -h host.docker.internal -p 54322 -d postgres -U postgres

Tests

npm run test

How it works

It works by querying the block_results RPC endpoint for each blocks and look for a slash event. For instance Canto got a slash event at block 10834497 which can be extracted like so:

http://localhost:26657/block_results?height=10834497 | \
jq '.result.finalize_block_events[] | select(.type == "slash")'

Output:

{
  "type": "slash",
  "attributes": [
    {
      "key": "address",
      "value": "cantovalcons1720m87a44r6h37pmuhkkwfs3d4x4str7g0acah",
      "index": true
    },
    {
      "key": "power",
      "value": "1415",
      "index": true
    },
    {
      "key": "reason",
      "value": "missing_signature",
      "index": true
    },
    {
      "key": "jailed",
      "value": "cantovalcons1720m87a44r6h37pmuhkkwfs3d4x4str7g0acah",
      "index": true
    },
    {
      "key": "mode",
      "value": "BeginBlock",
      "index": false
    }
  ]
}

Detection Modes

The indexer supports two slash detection modes:

Heuristic Mode (Default - O(log n))

Uses the SigningInfos query to detect jail events efficiently:

1. Find signing info availability - Binary search to find earliest height with signing info data
2. Detect jail events - Compare signing infos at start/end heights to identify jailed validators
3. Binary search exact blocks - For each jailed validator, binary search to find the exact jail block
4. Verify blocks - Fetch actual block results to confirm slash events

This is O(log n) per slash event instead of O(n) for sequential scanning.

Usage: This mode is enabled by default. Run normally:

CHAIN_NAME=kujira \
TENDERMINT_RPC_URL=https://archive.kujira.network \
npm run dev

Sequential Mode (O(n))

Traditional block-by-block scanning that queries every block in the range.

Usage: Set USE_HEURISTIC=false:

USE_HEURISTIC=false \
CHAIN_NAME=kujira \
TENDERMINT_RPC_URL=https://archive.kujira.network \
npm run dev

Signing Info Technical Details

The heuristic uses the signing info query which provides the most recent slashing information for each validator:

• Using the REST API: http://localhost:1317/cosmos/slashing/v1beta1/signing_infos
• Using RPC: http://localhost:26657/abci_query?path=%22/cosmos.slashing.v1beta1.Query/SigningInfos%22
• Using gRPC: grpcurl -plaintext localhost:9090 cosmos.slashing.v1beta1.Query/SigningInfos
• Using the CLI: cantod query slashing signing-infos

When using the CLI, you can supply the --height flag to query at specific heights. The indexer uses the RPC ABCI query with height parameter to enable the binary search algorithm.

For more details, refer to the documentation: Cosmos SDK Slashing Module.