ENSIndexer Startup Sequence
Below is an architecture diagram describing ENSIndexer start sequence in detail.
Ponder app lifecycle
Section titled “Ponder app lifecycle”Here is the top-level view on the ENSIndexer start sequence. It’s really the overview of the Ponder app lifecycle running inside the ENSIndexer instance. The example assumes that the ENSIndexer was started with the ENSINDEXER_SCHEMA_NAME environment variable set to prod_0, but the same sequence applies to any ENSIndexer Schema.
ENSIndexer Schema migrations
Section titled “ENSIndexer Schema migrations”When Ponder app lifecycle reaches the “Execute migrations for the prod_0 ENSIndexer Schema” step, Ponder will execute all pending migrations for the prod_0 ENSIndexer Schema.
This ensures that the database schema is up to date before indexing onchain events start.
Omnichain indexing strategy
Section titled “Omnichain indexing strategy”When Ponder app lifecycle reaches the “Run omnichain indexing strategy” step, Ponder will start writing data concurrently to Ponder Schema (caching RPC calls) and ENSIndexer Schema (storing indexed data). ENSIndexer app lifecycle “injects” a special “Execute onchain event handlers preconditions” step.
Init onchain event handlers
Section titled “Init onchain event handlers”The special “Execute onchain event handlers preconditions” step occurs before any onchain event is indexed. This allows ENSIndexer to execute ENSNode Schema migrations and populate ENSNode Metadata table with relevant data before any onchain event handlers are executed.
