Pull-Based Oracle

Overview

In a pull-based oracle model, publishers create signed updates off-chain and make them available for consumers to retrieve. A user includes the selected update with a transaction, and the oracle contract verifies and stores or exposes it. Pull delivery can avoid continuous on-chain updates for every feed and lets applications request data close to execution. It also moves update retrieval, fee payment, and timely submission into the user’s transaction path.

Contracts must verify signatures or proofs, feed identity, observation time, sequence, decimals, and maximum age. Applications need reliable update services and safe behavior when no fresh report is available. The submitter should not be able to choose an old but favorable report, reorder updates, or replay one across incompatible feeds or chains.

This distinction is essential when a technically valid oracle message produces an economically incorrect payment, liquidation, or release decision. Operational records should retain the exact report, block reference, source configuration, and rule that consumed it. Pull-Based Oracle should specify the reported value or event, authorized sources, aggregation method, update trigger, timestamp, decimals, and validity conditions. On-chain authenticity does not guarantee freshness, correct units, or fitness for a particular business action.

Multiple reporters do not create independence when they rely on the same exchange, API, infrastructure provider, or market methodology. The trust model includes data providers, node operators, signers, transmitters, contracts, governance, and any emergency controls. Integrations should enforce freshness and deviation limits, validate the expected feed or contract, and define fallback behavior for missing, disputed, or implausible data. High-value actions may require delayed execution, secondary evidence, or a circuit breaker rather than automatic acceptance.