Enum DbId

#[repr(u32)]
pub enum DbId {
    Service = 0,
    WriteOnly = 1,
    Native = 2,
    BlockLog = 3,
    HistoryEvent = 4,
    UiEvent = 5,
    MerkleEvent = 6,
    BlockProof = 7,
    PrevAuthServices = 8,
    NumChainDatabases = 9,
    Subjective = 64,
    NativeSubjective = 65,
    EndIndependent = 66,
    Temporary = 67,
}

Identify database to operate on

Native functions expose a set of databases which serve various purposes. This enum identifies which database to use when invoking those functions.

Variants

Service = 0

Services should store their tables here

The first 64 bits of the key match the service.

WriteOnly = 1

Data for RPC

Write-only during transactions, and read-only during RPC. Individual nodes may modify this database, expire data from this database, or wipe it entirely at will.

The first 64 bits of the key match the service.

Native = 2

Tables used by native code

This database enforces constraints during write. Only writable by privileged services, but readable by all services.

Some writes to this database indicate chain upgrades. If a privileged service writes to a table that an older node version doesn’t know about, or writes new fields to an existing table that an older node doesn’t know about, then that node will reject the write. If the producers accepted the write into a block, then the node will stop following the chain until it’s upgraded to a newer version.

BlockLog = 3

Block log

Transactions don’t have access to this, but RPC does.

HistoryEvent = 4

Long-term history event storage

Write-only during transactions, and read-only during RPC. Individual nodes may modify this database, expire data from this database, or wipe it entirely at will.

TODO: this policy may eventually change to allow time-limited read access during transactions.

Key is an auto-incremented, 64-bit unsigned number.

Value must begin with:

• 32 bit: block number
• 64 bit: service

Only usable with these native functions:

• crate::native_raw::putSequential
• crate::native_raw::getSequential

TODO: right now the value must begin with the service. Revisit whether beginning with the block number is useful.

UiEvent = 5

Short-term history event storage

These events are erased once the block that produced them becomes final. They notify user interfaces which subscribe to activity.

Write-only during transactions, and read-only during RPC. Individual nodes may modify this database, expire data from this database, or wipe it entirely at will.

Key is an auto-incremented, 64-bit unsigned number.

Value must begin with:

• 32 bit: block number
• 64 bit: service

Only usable with these native functions:

• crate::native_raw::putSequential
• crate::native_raw::getSequential

TODO: right now the value must begin with the service. Revisit whether beginning with the block number is useful.

MerkleEvent = 6

Events which go into the merkle tree

TODO: read support; right now only RPC mode can read

Services may produce these events during transactions and may read them up to 1 hour (configurable) after they were produced, or they reach finality, which ever is longer.

Key is an auto-incremented, 64-bit unsigned number.

Value must begin with:

• 32 bit: block number
• 64 bit: service

Only usable with these native functions:

• crate::native_raw::putSequential
• crate::native_raw::getSequential

TODO: right now the value must begin with the service. Revisit whether beginning with the block number is useful.

BlockProof = 7

block signatures

PrevAuthServices = 8

Not accessible to WASM. During joint consensus, this holds a subset of native as of the last irreversible block. Outside joint consensus, it is empty.

NumChainDatabases = 9

Number of defined databases

This number may grow in the future

Subjective = 64

Data that is not part of consensus

Only accessible to subjective services during transactions, but readable by all services during RPC. Doesn’t undo from aborting transactions, aborting blocks, or forking blocks. Individual nodes may modify this database or wipe

The first 64 bits of the key match the service.

NativeSubjective = 65

Subjective tables used by native code

Not fully implemented yet and not available to services. Doesn’t undo from aborting transactions, aborting blocks, or forking blocks.

EndIndependent = 66

Temporary = 67

Subjective tables that are local to the transaction/query/callback context.

Trait Implementations

impl Clone for DbId

fn clone(&self) -> DbId

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for DbId

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for DbId

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Pack for DbId

fn pack(&self, dest: &mut Vec<u8>)

Convert to fracpack format

fn packed(&self) -> Vec<u8>

Convert to fracpack format

impl Serialize for DbId

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl ToSchema for DbId

fn schema(_builder: &mut SchemaBuilder) -> AnyType

impl<'a> Unpack<'a> for DbId

fn unpack(src: &'a [u8], pos: &mut u32) -> Result<Self>

Convert from fracpack format. Also verifies the integrity of the data.

fn verify(src: &'a [u8], pos: &mut u32) -> Result<()>

Verify the integrity of fracpack data. You don’t need to call this if using [Pack::unpack] since it verifies integrity during unpack.

fn unpacked(src: &'a [u8]) -> Result<Self, Error>

Convert from fracpack format. Also verifies the integrity of the data.

fn verify_no_extra(src: &'a [u8]) -> Result<(), Error>

Verify the integrity of fracpack data, plus make sure there is no leftover data after it.

impl Copy for DbId