BAC-L2-COSMOS-111Cosmos SDK
Accounts, signatures and fees
How a transaction is authenticated and priced before it ever reaches business logic.
- Level
- L2 — Appchain developer
- Duration
- 3 h
- Track
- Cosmos SDK
- Maintainer
- Cosmos Lead Architect
Learning objectives
- 01Describe the decorator chain applied to every transaction
- 02Configure a minimum price and a fee policy
- 03Implement delegated authorisation between accounts
Guided lab
Configure the chain's fees and verify that an underpriced transaction is rejected.
Independent lab
Set up a fee-sponsorship mechanism for users holding no tokens.
Security angle
A zero minimum price makes the chain free to saturate.
Assessment
Documented, tested fee policy, rejection cases included.