Struct ClientBackup

pub struct ClientBackup {
    pub session_count: u64,
    pub metadata: Metadata,
    pub modules: BTreeMap<ModuleInstanceId, DynModuleBackup>,
}

Client state backup

Fields

session_count: u64

Session count taken right before taking the backup used to timestamp the backup file. Used for finding the most recent backup from all available ones.

Warning: Each particular module backup for each instance in Self::modules could have been taken earlier than that (e.g. older one used due to size limits), so modules MUST maintain their own session_counts.

metadata: Metadata

Application metadata

modules: BTreeMap<ModuleInstanceId, DynModuleBackup>

Module specific-backup (if supported)

Implementations

impl ClientBackup

pub const PADDING_ALIGNMENT: usize = 4_096usize

pub const PER_MODULE_SIZE_LIMIT_BYTES: usize = 32_768usize

“32kiB is enough for any module backup” –dpc

Federation storage is scarce, and since we can take older versions of the backup, temporarily going over the limit is not a big problem.

fn get_alignment_size(len: usize) -> usize

Align an ecoded message size up for better privacy

pub fn encrypt_to(&self, key: &LessSafeKey) -> Result<EncryptedClientBackup>

Encrypt with a key and turn into EncryptedClientBackup

fn validate_and_fallback_module_backups( self, last_backup: Option<&ClientBackup>, ) -> ClientBackup

Validate and fallback invalid parts of the backup

Given the size constraints and possible 3rd party modules, it seems to use older, but smaller versions of backups when current ones do not fit (either globally or in per-module limit).

Trait Implementations

impl Clone for ClientBackup

fn clone(&self) -> ClientBackup

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for ClientBackup

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

Formats the value using the given formatter.

impl Decodable for ClientBackup

fn consensus_decode<R: Read>( r: &mut R, modules: &ModuleDecoderRegistry, ) -> Result<Self, DecodeError>

Decode an object with a well-defined format.

fn consensus_decode_from_finite_reader<R>( r: &mut R, modules: &ModuleRegistry<Decoder, DecodingMode>, ) -> Result<Self, DecodeError>

where R: Read,

Decode Self from a size-limited reader.

fn consensus_decode_hex( hex: &str, modules: &ModuleRegistry<Decoder, DecodingMode>, ) -> Result<Self, DecodeError>

Decode an object from hex

fn consensus_decode_vec( bytes: Vec<u8>, modules: &ModuleRegistry<Decoder, DecodingMode>, ) -> Result<Self, DecodeError>

impl Encodable for ClientBackup

fn consensus_encode<W: Write>(&self, writer: &mut W) -> Result<usize, Error>

Encode an object with a well-defined format. Returns the number of bytes written on success.

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

Self::consensus_encode to newly allocated Vec<u8>

fn consensus_encode_to_hex(&self) -> String

Encode and convert to hex string representation

fn consensus_encode_to_len(&self) -> usize

Encode without storing the encoding, return the size

fn consensus_hash<H>(&self) -> H

where H: Hash, <H as Hash>::Engine: Write,

Generate a SHA256 hash of the consensus encoding using the default hash engine for H.

impl PartialEq for ClientBackup

fn eq(&self, other: &ClientBackup) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Eq for ClientBackup

impl StructuralPartialEq for ClientBackup