Module `0x1::DiemBlock`

This module defines a struct storing the metadata of the block and new block events.

Resource BlockMetadata
Struct NewBlockEvent
Constants
Function initialize_block_metadata
Function is_initialized
Function block_prologue
Function get_current_block_height
Module Specification
- Initialization

<pre><code>use <a href="CoreAddresses.md#0x1_CoreAddresses">0x1::CoreAddresses</a>; use <a href="DiemSystem.md#0x1_DiemSystem">0x1::DiemSystem</a>; use <a href="DiemTimestamp.md#0x1_DiemTimestamp">0x1::DiemTimestamp</a>; use <a href="../../../../../../move-stdlib/docs/Errors.md#0x1_Errors">0x1::Errors</a>; use <a href="../../../../../../move-stdlib/docs/Event.md#0x1_Event">0x1::Event</a>; </code></pre>

Resource `BlockMetadata`

<pre><code>resource struct <a href="DiemBlock.md#0x1_DiemBlock_BlockMetadata">BlockMetadata</a> </code></pre> <details> <summary>Fields</summary> <dl> <dt> <code>height: u64</code> </dt> <dd> Height of the current block </dd> <dt> <code>new_block_events: <a href="../../../../../../move-stdlib/docs/Event.md#0x1_Event_EventHandle">Event::EventHandle</a><<a href="DiemBlock.md#0x1_DiemBlock_NewBlockEvent">DiemBlock::NewBlockEvent</a>></code> </dt> <dd> Handle where events with the time of new blocks are emitted </dd> </dl> </details>

Struct `NewBlockEvent`

<pre><code>struct <a href="DiemBlock.md#0x1_DiemBlock_NewBlockEvent">NewBlockEvent</a> </code></pre> <details> <summary>Fields</summary> <dl> <dt> <code>round: u64</code> </dt> <dd> </dd> <dt> <code>proposer: address</code> </dt> <dd> </dd> <dt> <code>previous_block_votes: vector<address></code> </dt> <dd> </dd> <dt> <code>time_microseconds: u64</code> </dt> <dd> On-chain time during he block at the given height </dd> </dl> </details>

Constants

The <code><a href="DiemBlock.md#0x1_DiemBlock_BlockMetadata">BlockMetadata</a></code> resource is in an invalid state

<pre><code>const <a href="DiemBlock.md#0x1_DiemBlock_EBLOCK_METADATA">EBLOCK_METADATA</a>: u64 = 0; </code></pre>

An invalid signer was provided. Expected the signer to be the VM or a Validator.

<pre><code>const <a href="DiemBlock.md#0x1_DiemBlock_EVM_OR_VALIDATOR">EVM_OR_VALIDATOR</a>: u64 = 1; </code></pre>

Function `initialize_block_metadata`

This can only be invoked by the Association address, and only a single time. Currently, it is invoked in the genesis transaction

<pre><code>public fun <a href="DiemBlock.md#0x1_DiemBlock_initialize_block_metadata">initialize_block_metadata</a>(account: &signer) </code></pre> <details> <summary>Implementation</summary> <pre><code>public fun <a href="DiemBlock.md#0x1_DiemBlock_initialize_block_metadata">initialize_block_metadata</a>(account: &signer) { <a href="DiemTimestamp.md#0x1_DiemTimestamp_assert_genesis">DiemTimestamp::assert_genesis</a>(); // Operational constraint, only callable by the Association address <a href="CoreAddresses.md#0x1_CoreAddresses_assert_diem_root">CoreAddresses::assert_diem_root</a>(account); assert(!<a href="DiemBlock.md#0x1_DiemBlock_is_initialized">is_initialized</a>(), <a href="../../../../../../move-stdlib/docs/Errors.md#0x1_Errors_already_published">Errors::already_published</a>(<a href="DiemBlock.md#0x1_DiemBlock_EBLOCK_METADATA">EBLOCK_METADATA</a>)); move_to<<a href="DiemBlock.md#0x1_DiemBlock_BlockMetadata">BlockMetadata</a>>( account, <a href="DiemBlock.md#0x1_DiemBlock_BlockMetadata">BlockMetadata</a> { height: 0, new_block_events: <a href="../../../../../../move-stdlib/docs/Event.md#0x1_Event_new_event_handle">Event::new_event_handle</a><<a href="DiemBlock.md#0x1_DiemBlock_NewBlockEvent">Self::NewBlockEvent</a>>(account), } ); } </code></pre> </details> <details> <summary>Specification</summary> <pre><code>include <a href="DiemTimestamp.md#0x1_DiemTimestamp_AbortsIfNotGenesis">DiemTimestamp::AbortsIfNotGenesis</a>; include <a href="CoreAddresses.md#0x1_CoreAddresses_AbortsIfNotDiemRoot">CoreAddresses::AbortsIfNotDiemRoot</a>; aborts_if <a href="DiemBlock.md#0x1_DiemBlock_is_initialized">is_initialized</a>() with <a href="../../../../../../move-stdlib/docs/Errors.md#0x1_Errors_ALREADY_PUBLISHED">Errors::ALREADY_PUBLISHED</a>; ensures <a href="DiemBlock.md#0x1_DiemBlock_is_initialized">is_initialized</a>(); ensures <a href="DiemBlock.md#0x1_DiemBlock_get_current_block_height">get_current_block_height</a>() == 0; </code></pre> </details>

Function `is_initialized`

Helper function to determine whether this module has been initialized.

<pre><code>fun <a href="DiemBlock.md#0x1_DiemBlock_is_initialized">is_initialized</a>(): bool </code></pre> <details> <summary>Implementation</summary> <pre><code>fun <a href="DiemBlock.md#0x1_DiemBlock_is_initialized">is_initialized</a>(): bool { exists<<a href="DiemBlock.md#0x1_DiemBlock_BlockMetadata">BlockMetadata</a>>(<a href="CoreAddresses.md#0x1_CoreAddresses_DIEM_ROOT_ADDRESS">CoreAddresses::DIEM_ROOT_ADDRESS</a>()) } </code></pre> </details>

Function `block_prologue`

Set the metadata for the current block. The runtime always runs this before executing the transactions in a block.

<pre><code>fun <a href="DiemBlock.md#0x1_DiemBlock_block_prologue">block_prologue</a>(vm: signer, round: u64, timestamp: u64, previous_block_votes: vector<address>, proposer: address) </code></pre> <details> <summary>Implementation</summary> <pre><code>fun <a href="DiemBlock.md#0x1_DiemBlock_block_prologue">block_prologue</a>( vm: signer, round: u64, timestamp: u64, previous_block_votes: vector<address>, proposer: address ) acquires <a href="DiemBlock.md#0x1_DiemBlock_BlockMetadata">BlockMetadata</a> { <a href="DiemTimestamp.md#0x1_DiemTimestamp_assert_operating">DiemTimestamp::assert_operating</a>(); // Operational constraint: can only be invoked by the VM. <a href="CoreAddresses.md#0x1_CoreAddresses_assert_vm">CoreAddresses::assert_vm</a>(&vm); // Authorization assert( proposer == <a href="CoreAddresses.md#0x1_CoreAddresses_VM_RESERVED_ADDRESS">CoreAddresses::VM_RESERVED_ADDRESS</a>() || <a href="DiemSystem.md#0x1_DiemSystem_is_validator">DiemSystem::is_validator</a>(proposer), <a href="../../../../../../move-stdlib/docs/Errors.md#0x1_Errors_requires_address">Errors::requires_address</a>(<a href="DiemBlock.md#0x1_DiemBlock_EVM_OR_VALIDATOR">EVM_OR_VALIDATOR</a>) ); let block_metadata_ref = borrow_global_mut<<a href="DiemBlock.md#0x1_DiemBlock_BlockMetadata">BlockMetadata</a>>(<a href="CoreAddresses.md#0x1_CoreAddresses_DIEM_ROOT_ADDRESS">CoreAddresses::DIEM_ROOT_ADDRESS</a>()); <a href="DiemTimestamp.md#0x1_DiemTimestamp_update_global_time">DiemTimestamp::update_global_time</a>(&vm, proposer, timestamp); block_metadata_ref.height = block_metadata_ref.height + 1; <a href="../../../../../../move-stdlib/docs/Event.md#0x1_Event_emit_event">Event::emit_event</a><<a href="DiemBlock.md#0x1_DiemBlock_NewBlockEvent">NewBlockEvent</a>>( &mut block_metadata_ref.new_block_events, <a href="DiemBlock.md#0x1_DiemBlock_NewBlockEvent">NewBlockEvent</a> { round, proposer, previous_block_votes, time_microseconds: timestamp, } ); } </code></pre> </details> <details> <summary>Specification</summary> <pre><code>include <a href="DiemTimestamp.md#0x1_DiemTimestamp_AbortsIfNotOperating">DiemTimestamp::AbortsIfNotOperating</a>; include <a href="CoreAddresses.md#0x1_CoreAddresses_AbortsIfNotVM">CoreAddresses::AbortsIfNotVM</a>{account: vm}; aborts_if proposer != <a href="CoreAddresses.md#0x1_CoreAddresses_VM_RESERVED_ADDRESS">CoreAddresses::VM_RESERVED_ADDRESS</a>() && !<a href="DiemSystem.md#0x1_DiemSystem_spec_is_validator">DiemSystem::spec_is_validator</a>(proposer) with <a href="../../../../../../move-stdlib/docs/Errors.md#0x1_Errors_REQUIRES_ADDRESS">Errors::REQUIRES_ADDRESS</a>; ensures <a href="DiemTimestamp.md#0x1_DiemTimestamp_spec_now_microseconds">DiemTimestamp::spec_now_microseconds</a>() == timestamp; ensures <a href="DiemBlock.md#0x1_DiemBlock_get_current_block_height">get_current_block_height</a>() == old(<a href="DiemBlock.md#0x1_DiemBlock_get_current_block_height">get_current_block_height</a>()) + 1; aborts_if <a href="DiemBlock.md#0x1_DiemBlock_get_current_block_height">get_current_block_height</a>() + 1 > MAX_U64 with EXECUTION_FAILURE; include <a href="DiemBlock.md#0x1_DiemBlock_BlockPrologueEmits">BlockPrologueEmits</a>; </code></pre>

<pre><code>schema <a href="DiemBlock.md#0x1_DiemBlock_BlockPrologueEmits">BlockPrologueEmits</a> { round: u64; timestamp: u64; previous_block_votes: vector<address>; proposer: address; <a name="0x1_DiemBlock_handle$4"></a> let handle = global<<a href="DiemBlock.md#0x1_DiemBlock_BlockMetadata">BlockMetadata</a>>(<a href="CoreAddresses.md#0x1_CoreAddresses_DIEM_ROOT_ADDRESS">CoreAddresses::DIEM_ROOT_ADDRESS</a>()).new_block_events; <a name="0x1_DiemBlock_msg$5"></a> let msg = <a href="DiemBlock.md#0x1_DiemBlock_NewBlockEvent">NewBlockEvent</a> { round, proposer, previous_block_votes, time_microseconds: timestamp, }; emits msg to handle; } </code></pre> </details>

Function `get_current_block_height`

Get the current block height

<pre><code>public fun <a href="DiemBlock.md#0x1_DiemBlock_get_current_block_height">get_current_block_height</a>(): u64 </code></pre> <details> <summary>Implementation</summary> <pre><code>public fun <a href="DiemBlock.md#0x1_DiemBlock_get_current_block_height">get_current_block_height</a>(): u64 acquires <a href="DiemBlock.md#0x1_DiemBlock_BlockMetadata">BlockMetadata</a> { assert(<a href="DiemBlock.md#0x1_DiemBlock_is_initialized">is_initialized</a>(), <a href="../../../../../../move-stdlib/docs/Errors.md#0x1_Errors_not_published">Errors::not_published</a>(<a href="DiemBlock.md#0x1_DiemBlock_EBLOCK_METADATA">EBLOCK_METADATA</a>)); borrow_global<<a href="DiemBlock.md#0x1_DiemBlock_BlockMetadata">BlockMetadata</a>>(<a href="CoreAddresses.md#0x1_CoreAddresses_DIEM_ROOT_ADDRESS">CoreAddresses::DIEM_ROOT_ADDRESS</a>()).height } </code></pre> </details>

Module Specification

Initialization

This implies that <code><a href="DiemBlock.md#0x1_DiemBlock_BlockMetadata">BlockMetadata</a></code> is published after initialization and stays published ever after

<pre><code>invariant [global] <a href="DiemTimestamp.md#0x1_DiemTimestamp_is_operating">DiemTimestamp::is_operating</a>() ==> <a href="DiemBlock.md#0x1_DiemBlock_is_initialized">is_initialized</a>(); </code></pre>

Module `0x1::DiemBlock`

Module 0x1::DiemBlock

Resource BlockMetadata

Struct NewBlockEvent

Constants

Function initialize_block_metadata

Function is_initialized

Function block_prologue

Function get_current_block_height

Module Specification

Initialization

Module `0x1::DiemBlock`

Resource `BlockMetadata`

Struct `NewBlockEvent`

Function `initialize_block_metadata`

Function `is_initialized`

Function `block_prologue`

Function `get_current_block_height`