Indexer Architecture Overview

Learn how the indexing architecture works in Blockscout

Presentation Highlights

The following presentation describes the past, present and future iterations of Blockscout along with details about how block imports work both synchonously and asynchronously, and a description of the regular and on-demand fetchers.

1MB

Blockscout Indexer Architecture Overview.pdf

pdf

Blockscout indexers

See the pdf ⬆️ for more details about the Blockscout indexer. The indexing architecture includes all of the following indexers and fetchers

Primary Indexers

Both indexers utilize synchonous and asynchronous operations.

• Realtime: Imports new block data from the head of the chain.

• Catchup: Imports data down the chain (starting from the head and moving backwards towards the genesis block)

Secondary fetchers

Regular

• Internal transactions

• Pending transactions

• Dropped/Replaced transactions

• Contract bytecodes

• Block rewards

• Token catalog

• Token/coin balances

• NFT instances

• Uncles

On Demand

• Coin/token balances update

• Contract bytecodes fetch/re-check

• Contract source codes lookup

• NFT instance metadata re-fetch

• Token total supply

Off-chain integrations

• Coin / token price, market cap, tvl sources: CMC, Coingecko, Cryptorank, Defillama

• Smart contract verification: ETH bytecode DB, Sourcify

• Data enrichment: ENS names, public tags, AI interpreters (own, Noves Fi), sc security scanners (Solidityscan), assets portfolio (Zerion)

• Chain initialization data import: pre-mined coins, precompiled smart-contracts

Chain-specific fetchers

• There are more than a dozen of chain-specific data fetchers to account for chain differences including arbitrum, optimism, polygon edge, polygon zkevm, zksync etc.

Temporary fetchers

• Used once to resolve possible data inconsistencies.