Crate frame_system

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System Pallet

The System pallet provides low-level access to core types and cross-cutting utilities. It acts as the base layer for other pallets to interact with the Substrate framework components.

Overview

The System pallet defines the core data types used in a Substrate runtime. It also provides several utility functions (see Pallet) for other FRAME pallets.

In addition, it manages the storage items for extrinsics data, indexes, event records, and digest items, among other things that support the execution of the current block.

It also handles low-level tasks like depositing logs, basic set up and take down of temporary storage entries, and access to previous block hashes.

Interface

Dispatchable Functions

The System pallet does not implement any dispatchable functions.

Public Functions

See the Pallet struct for details of publicly available functions.

Signed Extensions

The System pallet defines the following extensions:

  • CheckWeight: Checks the weight and length of the block and ensure that it does not exceed the limits.
  • CheckNonce: Checks the nonce of the transaction. Contains a single payload of type T::Nonce.
  • CheckEra: Checks the era of the transaction. Contains a single payload of type Era.
  • CheckGenesis: Checks the provided genesis hash of the transaction. Must be a part of the signed payload of the transaction.
  • CheckSpecVersion: Checks that the runtime version is the same as the one used to sign the transaction.
  • CheckTxVersion: Checks that the transaction version is the same as the one used to sign the transaction.

Lookup the runtime aggregator file (e.g. node/runtime) to see the full list of signed extensions included in a chain.

Re-exports

Modules

  • Block resource limits configuration structures.
  • Migrate the reference counting state.
  • Provide types to help defining a mock environment when testing pallets.
  • Module helpers for off-chain calls.
  • The pallet module in each FRAME pallet hosts the most important items needed to construct this pallet.
  • Prelude to be used alongside pallet macro, for ease of use.
  • Autogenerated weights for frame_system

Structs

Enums

  • Some resultant status relevant to decrementing a provider/self-sufficient reference.
  • Some resultant status relevant to incrementing a provider/self-sufficient reference.
  • A phase of a block’s execution.
  • Origin for the System pallet.
  • Reference status; can be either referenced or unreferenced.

Traits

  • Numeric limits over the ability to add a consumer ref using inc_consumers.
  • Do something when we should be setting the code.

Functions

  • Ensure that the origin o represents an unsigned extrinsic. Returns Ok or an Err otherwise.
  • Ensure that the origin o represents the root. Returns Ok or an Err otherwise.
  • Ensure that the origin o represents a signed extrinsic (i.e. transaction). Returns Ok with the account that signed the extrinsic or an Err otherwise.
  • Ensure that the origin o represents either a signed extrinsic (i.e. transaction) or the root. Returns Ok with the account that signed the extrinsic, None if it was root, or an Err otherwise.
  • Compute the trie root of a list of extrinsics.
  • Compute the trie root of a list of extrinsics.
  • Split an option into two constituent options, as defined by a splitter function.
  • Returns a 32 byte datum which is guaranteed to be universally unique. entropy is provided as a facility to reduce the potential for precalculating results.

Type Definitions