IFdbDatabase

Namespace: FoundationDB.Client · interface

Implements: IFdbRetryable, IFdbReadOnlyRetryable, IDisposable

Database connection context.

Properties

Cancellation

CancellationToken Cancellation { get; }

Returns a cancellation token that is linked with the lifetime of this database instance

The token will be cancelled if the database instance is disposed

DirectoryLayer

FdbDirectoryLayer DirectoryLayer { get; }

Directory Layer used by this database instance

IsReadOnly

bool IsReadOnly { get; }

If true, this database instance will only allow starting read-only transactions.

Name

string Name { get; }

Name of the database

Options

IFdbDatabaseOptions Options { get; }

Helper that can set options for this database

Root

FdbDirectorySubspaceLocation Root { get; }

Returns the root path used by this database instance

Time

TimeProvider Time { get; }

Time source used by this database for managed waits and timestamps (watch idle-timeouts and transaction-log stamps).

Defaults to the system clock. A test can inject a fake provider (for example through a FakeDbStore or AddFakeDb) so that managed time-based waits advance with virtual time instead of the wall clock.

A database backed by the native fdb client must keep a system-based provider: the native client enforces its own timeouts and retry backoff, so a fake clock cannot drive those and would only desynchronize the managed bulk-write commit cadence from the native five-second transaction limit.

Methods

BeginTransaction

IFdbTransaction BeginTransaction(FdbTransactionMode mode, CancellationToken ct, FdbOperationContext context = null)

Starts a new transaction on this database, with the specified mode

• mode — Mode of the transaction (read-only, read-write, ....)
• ct — Optional cancellation token that can abort all pending async operations started by this transaction.
• context — Existing parent context, if the transaction needs to be linked with a retry loop, or a parent transaction. If null, will create a new standalone context valid only for this transaction

Returns: New transaction instance that can read from or write to the database.

You MUST call Dispose() on the transaction when you are done with it. You SHOULD wrap it in a 'using' statement to ensure that it is disposed in all cases.

using(var tr = db.BeginTransaction(CancellationToken.None))
{
	tr.Set(Slice.FromString("Hello"), Slice.FromString("World"));
	tr.Clear(Slice.FromString("OldValue"));
	await tr.CommitAsync();
}

BeginTransactionAsync

ValueTask<IFdbTransaction> BeginTransactionAsync(FdbTransactionMode mode, CancellationToken ct, FdbOperationContext context = null)

Starts a new transaction on this database, with the specified mode

• mode — Mode of the transaction (read-only, read-write, ....)
• ct — Optional cancellation token that can abort all pending async operations started by this transaction.
• context — Existing parent context, if the transaction needs to be linked with a retry loop, or a parent transaction. If null, will create a new standalone context valid only for this transaction

Returns: New transaction instance that can read from or write to the database.

You MUST call Dispose() on the transaction when you are done with it. You SHOULD wrap it in a 'using' statement to ensure that it is disposed in all cases.

using(var tr = db.BeginTransaction(CancellationToken.None))
{
	tr.Set(Slice.FromString("Hello"), Slice.FromString("World"));
	tr.Clear(Slice.FromString("OldValue"));
	await tr.CommitAsync();
}

CreateSnapshotAsync

Task CreateSnapshotAsync(string uid, string snapCommand, CancellationToken ct)

Creates a new snapshot of the database

ForceRecoveryWithDataLossAsync

Task ForceRecoveryWithDataLossAsync(string dcId, CancellationToken ct)

Forces a recovery that could induce data loss

GetApiVersion

int GetApiVersion()

Returns the currently enforced API version for this database instance.

GetClientStatus

Task<Slice> GetClientStatus(CancellationToken ct)

Returns the client status

GetMainThreadBusyness

double GetMainThreadBusyness()

Returns a value between 0 and 1 that reflect the saturation of the client main thread.

Returns: Value between 0 (no activity) and 1 (completely saturated)

The value is updated in the background at regular interval (by default every second).

GetServerProtocolVersionAsync

Task<FdbProtocolVersion> GetServerProtocolVersionAsync(FdbProtocolVersion expectedVersion, CancellationToken ct)

Returns the protocol version reported by the coordinator this client is connected to.

• expectedVersion — If this value is not equal to None, the task will not complete until the protocol version is different than expected (or ct fires).
• ct — Token used to cancel the operation.

Returns: Task that returns the current protocol version

This will never complete if the remote server is running a protocol from FDB 5.0 or older.

GetTenant

IFdbTenant GetTenant(FdbTenantName name)

Gets a tenant from this database

• name — Name of the tenant

Returns: Instance that can execute transactions in the context of this tenant

RebootWorkerAsync

Task RebootWorkerAsync(string name, bool check, int duration, CancellationToken ct)

Attempts to reboot a work in the cluster

SetDefaultLogHandler

void SetDefaultLogHandler(Action<FdbTransactionLog> handler, FdbLoggingOptions options = null)

Sets the default log handler for this database

• handler — Default handler that is attached to any new transaction, and will be invoked when they complete.

This handler may not be called if logging is disabled, if a transaction overrides its handler, or if it calls