Enum FirestoreWritePrecondition

pub enum FirestoreWritePrecondition {
    Exists(bool),
    UpdateTime(DateTime<Utc>),
}

A precondition on a document, used for conditional write operations in Firestore.

Preconditions allow you to specify conditions that must be met for a write operation (create, update, delete) to succeed. If the precondition is not met, the operation will fail, typically with a DataConflictError or similar.

Variants

Exists(bool)

The target document must exist (if true) or must not exist (if false).

• Exists(true): The operation will only succeed if the document already exists. Useful for conditional updates or deletes.
• Exists(false): The operation will only succeed if the document does not already exist. Useful for conditional creates (to prevent overwriting).

UpdateTime(DateTime<Utc>)

The target document must exist and its update_time must match the provided timestamp.

This is used for optimistic concurrency control. The operation will only succeed if the document has not been modified since the specified update_time. The DateTime<Utc> must be microsecond-aligned, as Firestore timestamps have microsecond precision.

Trait Implementations

impl Clone for FirestoreWritePrecondition

fn clone(&self) -> FirestoreWritePrecondition

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for FirestoreWritePrecondition

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

Formats the value using the given formatter.

impl PartialEq for FirestoreWritePrecondition

fn eq(&self, other: &FirestoreWritePrecondition) -> 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 TryInto<Precondition> for FirestoreWritePrecondition

type Error = FirestoreError

The type returned in the event of a conversion error.

fn try_into(self) -> Result<Precondition, Self::Error>

Performs the conversion.

impl Eq for FirestoreWritePrecondition

impl StructuralPartialEq for FirestoreWritePrecondition