Struct AuditEvent 

pub struct AuditEvent {
    pub id: u64,
    pub timestamp: i64,
    pub principal: String,
    pub action: AuditAction,
    pub resource: String,
    pub decision: AuditDecision,
    pub source_ip: Option<String>,
    pub request_id: Option<String>,
    pub metadata: HashMap<String, String>,
    pub prev_hash: Option<String>,
    pub event_hash: Option<String>,
}

A structured audit event capturing a security-relevant operation.

Events carry a SHA-256 hash chain — each event’s event_hash covers prev_hash || canonical_payload, making log tampering detectable by verifying the chain with verify_hash_chain.

Fields

id: u64

Monotonically increasing event ID.

timestamp: i64

Nanosecond timestamp.

principal: String

The principal (user / service) that performed the action.

action: AuditAction

The action performed.

resource: String

The resource targeted (measurement, series, etc.).

decision: AuditDecision

Authorization decision.

source_ip: Option<String>

Source IP address (if available).

request_id: Option<String>

Request ID for correlation.

metadata: HashMap<String, String>

Additional context (e.g., deny reasons, error details).

prev_hash: Option<String>

Hex SHA-256 hash of the previous event (or None for the first event in the chain).

event_hash: Option<String>

Hex SHA-256 hash of prev_hash || canonical_payload.

Implementations

impl AuditEvent

pub fn new( principal: impl Into<String>, action: AuditAction, resource: impl Into<String>, decision: AuditDecision, ) -> Self

Create a new audit event builder.

pub fn with_source_ip(self, ip: impl Into<String>) -> Self

Set the source IP.

pub fn with_request_id(self, id: impl Into<String>) -> Self

Set the request ID.

pub fn with_metadata( self, key: impl Into<String>, value: impl Into<String>, ) -> Self

Add a metadata key-value pair.

pub fn with_timestamp(self, ts: i64) -> Self

Set the timestamp explicitly (for tests).

impl AuditEvent

pub fn seal(&mut self, prev_hash: Option<&str>)

Compute HMAC-SHA-256 of prev_hash || canonical_payload and set self.prev_hash and self.event_hash.

Uses HMAC with a secret key instead of plain SHA-256, so an attacker with database write access cannot recompute the chain. Falls back to plain SHA-256 if no key is provided (backward compat).

pub fn seal_with_key( &mut self, prev_hash: Option<&str>, hmac_key: Option<&[u8]>, )

Seal the event hash with an optional HMAC key.

When hmac_key is Some, uses HMAC-SHA-256 for tamper resistance. When None, falls back to plain SHA-256 (backward compatible).

Trait Implementations

impl Clone for AuditEvent

fn clone(&self) -> AuditEvent

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for AuditEvent

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for AuditEvent

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

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Display for AuditEvent

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

Formats the value using the given formatter.

impl Serialize for AuditEvent

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

where __S: Serializer,

Serialize this value into the given Serde serializer.