TenantContextGuard class

Namespace: Tenantry.EfCore · Package: Tenantry.EfCore · API reference

An extension point: for code that extends the package, such as another package that builds on it. An application rarely needs it.

An interceptor that checks a context before it opens a connection, before every command it runs and before SaveChanges, so a context that would reach the wrong tenant's data throws instead. Derive from it to fail closed on a condition of your own, such as a context whose schema is not the current tenant's.

Add it to a context's options with AddInterceptors, or from an ITenantDbContextOptionsContributor. EF Core raises no event for a connection that is already open, so a context opened under one tenant and then used under another is caught at its next command. SaveChanges is checked before it starts, because EF Core wraps an exception thrown while a save runs its commands in a DbUpdateException. A command EF Core runs without a context (a HiLo sequence fetch) is checked against the context that opened its connection.

In a context that uses UseTenantry(), the check runs before Tenantry stamps the save's new entities with the current tenant, wherever the guard is among the context's interceptors, so a save it refuses leaves the tracked entities as they were. Interceptors of your own run in the order they were added: add the guard before one that changes entities when a save starts.

Throw TenantNotResolvedException when the context needs a tenant and none is current, and TenantIsolationViolationException when it would use another tenant's data.

[EditorBrowsable(EditorBrowsableState.Advanced)]
public abstract class TenantContextGuard : IDbConnectionInterceptor, IDbCommandInterceptor, ISaveChangesInterceptor, IInterceptor

Implements IDbConnectionInterceptor, IDbCommandInterceptor, ISaveChangesInterceptor, IInterceptor.

MethodsCopy Anchor Link

Check(DbContext)Copy Anchor Link

Throws when context must not touch the database now.

protected abstract void Check(DbContext context)

Parameters:

• context DbContext: The context about to open a connection, run a command or save.

ConnectionOpening(DbConnection, ConnectionEventData, InterceptionResult)Copy Anchor Link

Called just before EF intends to call Open().

public virtual InterceptionResult ConnectionOpening(DbConnection connection, ConnectionEventData eventData, InterceptionResult result)

Parameters:

• connection DbConnection: The connection.
• eventData ConnectionEventData: Contextual information about the connection.
• result InterceptionResult: Represents the current result if one exists. This value will have IsSuppressed set to true if some previous interceptor suppressed execution by calling Suppress(). This value is typically used as the return value for the implementation of this method.

Returns: InterceptionResult: If IsSuppressed is false, then EF will continue as normal. If IsSuppressed is true, then EF will suppress the operation it was about to perform. An implementation of this method for any interceptor that is not attempting to suppress the operation is to return the result value passed in.

ConnectionOpeningAsync(DbConnection, ConnectionEventData, InterceptionResult, CancellationToken)Copy Anchor Link

Called just before EF intends to call OpenAsync().

public virtual ValueTask<InterceptionResult> ConnectionOpeningAsync(DbConnection connection, ConnectionEventData eventData, InterceptionResult result, CancellationToken cancellationToken = default)

Parameters:

• connection DbConnection: The connection.
• eventData ConnectionEventData: Contextual information about the connection.
• result InterceptionResult: Represents the current result if one exists. This value will have IsSuppressed set to true if some previous interceptor suppressed execution by calling Suppress(). This value is typically used as the return value for the implementation of this method.
• cancellationToken CancellationToken: A CancellationToken to observe while waiting for the task to complete.

Returns: ValueTask<InterceptionResult>: If IsSuppressed is false, then EF will continue as normal. If IsSuppressed is true, then EF will suppress the operation it was about to perform. An implementation of this method for any interceptor that is not attempting to suppress the operation is to return the result value passed in.

Exceptions:

• OperationCanceledException: If the CancellationToken is canceled.

FindContext(DbConnection?)Copy Anchor Link

The context that owns connection, for an event that names none. By default, the last context that opened it.

protected virtual DbContext? FindContext(DbConnection? connection)

Parameters:

• connection DbConnection: The connection.

Returns: DbContext: The context, or null when none is known.

NonQueryExecuting(DbCommand, CommandEventData, InterceptionResult<int>)Copy Anchor Link

Called just before EF intends to call ExecuteNonQuery().

public InterceptionResult<int> NonQueryExecuting(DbCommand command, CommandEventData eventData, InterceptionResult<int> result)

Parameters:

• command DbCommand: The command.
• eventData CommandEventData: Contextual information about the command and execution.
• result InterceptionResult<int>: Represents the current result if one exists. This value will have HasResult set to true if some previous interceptor suppressed execution by calling SuppressWithResult(TResult). This value is typically used as the return value for the implementation of this method.

Returns: InterceptionResult<int>: If HasResult is false, the EF will continue as normal. If HasResult is true, then EF will suppress the operation it was about to perform and use Result instead. An implementation of this method for any interceptor that is not attempting to change the result is to return the result value passed in.

NonQueryExecutingAsync(DbCommand, CommandEventData, InterceptionResult<int>, CancellationToken)Copy Anchor Link

Called just before EF intends to call ExecuteNonQueryAsync().

public ValueTask<InterceptionResult<int>> NonQueryExecutingAsync(DbCommand command, CommandEventData eventData, InterceptionResult<int> result, CancellationToken cancellationToken = default)

Parameters:

• command DbCommand: The command.
• eventData CommandEventData: Contextual information about the command and execution.
• result InterceptionResult<int>: Represents the current result if one exists. This value will have HasResult set to true if some previous interceptor suppressed execution by calling SuppressWithResult(TResult). This value is typically used as the return value for the implementation of this method.
• cancellationToken CancellationToken: A CancellationToken to observe while waiting for the task to complete.

Returns: ValueTask<InterceptionResult<int>>: If HasResult is false, the EF will continue as normal. If HasResult is true, then EF will suppress the operation it was about to perform and use Result instead. An implementation of this method for any interceptor that is not attempting to change the result is to return the result value passed in, often using FromResult<TResult>(TResult)

Exceptions:

• OperationCanceledException: If the CancellationToken is canceled.

Opening(DbConnection, ConnectionEventData)Copy Anchor Link

The context a connection event belongs to, recorded for the connection's later commands.

protected DbContext? Opening(DbConnection connection, ConnectionEventData eventData)

Parameters:

• connection DbConnection: The connection.
• eventData ConnectionEventData: The event.

Returns: DbContext: The context, or null when none is known.

ReaderExecuting(DbCommand, CommandEventData, InterceptionResult<DbDataReader>)Copy Anchor Link

Called just before EF intends to call ExecuteReader().

public InterceptionResult<DbDataReader> ReaderExecuting(DbCommand command, CommandEventData eventData, InterceptionResult<DbDataReader> result)

Parameters:

• command DbCommand: The command.
• eventData CommandEventData: Contextual information about the command and execution.
• result InterceptionResult<DbDataReader>: Represents the current result if one exists. This value will have HasResult set to true if some previous interceptor suppressed execution by calling SuppressWithResult(TResult). This value is typically used as the return value for the implementation of this method.

Returns: InterceptionResult<DbDataReader>: If HasResult is false, the EF will continue as normal. If HasResult is true, then EF will suppress the operation it was about to perform and use Result instead. An implementation of this method for any interceptor that is not attempting to change the result is to return the result value passed in.

ReaderExecutingAsync(DbCommand, CommandEventData, InterceptionResult<DbDataReader>, CancellationToken)Copy Anchor Link

Called just before EF intends to call ExecuteReaderAsync().

public ValueTask<InterceptionResult<DbDataReader>> ReaderExecutingAsync(DbCommand command, CommandEventData eventData, InterceptionResult<DbDataReader> result, CancellationToken cancellationToken = default)

Parameters:

• command DbCommand: The command.
• eventData CommandEventData: Contextual information about the command and execution.
• result InterceptionResult<DbDataReader>: Represents the current result if one exists. This value will have HasResult set to true if some previous interceptor suppressed execution by calling SuppressWithResult(TResult). This value is typically used as the return value for the implementation of this method.
• cancellationToken CancellationToken: A CancellationToken to observe while waiting for the task to complete.

Returns: ValueTask<InterceptionResult<DbDataReader>>: If HasResult is false, the EF will continue as normal. If HasResult is true, then EF will suppress the operation it was about to perform and use Result instead. An implementation of this method for any interceptor that is not attempting to change the result is to return the result value passed in, often using FromResult<TResult>(TResult)

Exceptions:

• OperationCanceledException: If the CancellationToken is canceled.

SavingChanges(DbContextEventData, InterceptionResult<int>)Copy Anchor Link

Called at the start of <see cref="O:DbContext.SaveChanges"></see>.

public virtual InterceptionResult<int> SavingChanges(DbContextEventData eventData, InterceptionResult<int> result)

Parameters:

• eventData DbContextEventData: Contextual information about the DbContext being used.
• result InterceptionResult<int>: Represents the current result if one exists. This value will have HasResult set to true if some previous interceptor suppressed execution by calling SuppressWithResult(TResult). This value is typically used as the return value for the implementation of this method.

Returns: InterceptionResult<int>: If HasResult is false, the EF will continue as normal. If HasResult is true, then EF will suppress the operation it was about to perform and use Result instead. An implementation of this method for any interceptor that is not attempting to change the result is to return the result value passed in.

SavingChangesAsync(DbContextEventData, InterceptionResult<int>, CancellationToken)Copy Anchor Link

Called at the start of <see cref="O:DbContext.SaveChangesAsync"></see>.

public virtual ValueTask<InterceptionResult<int>> SavingChangesAsync(DbContextEventData eventData, InterceptionResult<int> result, CancellationToken cancellationToken = default)

Parameters:

• eventData DbContextEventData: Contextual information about the DbContext being used.
• result InterceptionResult<int>: Represents the current result if one exists. This value will have HasResult set to true if some previous interceptor suppressed execution by calling SuppressWithResult(TResult). This value is typically used as the return value for the implementation of this method.
• cancellationToken CancellationToken: A CancellationToken to observe while waiting for the task to complete.

Returns: ValueTask<InterceptionResult<int>>: If HasResult is false, the EF will continue as normal. If HasResult is true, then EF will suppress the operation it was about to perform and use Result instead. An implementation of this method for any interceptor that is not attempting to change the result is to return the result value passed in.

Exceptions:

• OperationCanceledException: If the CancellationToken is canceled.

ScalarExecuting(DbCommand, CommandEventData, InterceptionResult<object>)Copy Anchor Link

Called just before EF intends to call ExecuteScalar().

public InterceptionResult<object> ScalarExecuting(DbCommand command, CommandEventData eventData, InterceptionResult<object> result)

Parameters:

• command DbCommand: The command.
• eventData CommandEventData: Contextual information about the command and execution.
• result InterceptionResult<object>: Represents the current result if one exists. This value will have HasResult set to true if some previous interceptor suppressed execution by calling SuppressWithResult(TResult). This value is typically used as the return value for the implementation of this method.

Returns: InterceptionResult<object>: If HasResult is false, the EF will continue as normal. If HasResult is true, then EF will suppress the operation it was about to perform and use Result instead. An implementation of this method for any interceptor that is not attempting to change the result is to return the result value passed in.

ScalarExecutingAsync(DbCommand, CommandEventData, InterceptionResult<object>, CancellationToken)Copy Anchor Link

Called just before EF intends to call ExecuteScalarAsync().

public ValueTask<InterceptionResult<object>> ScalarExecutingAsync(DbCommand command, CommandEventData eventData, InterceptionResult<object> result, CancellationToken cancellationToken = default)

Parameters:

• command DbCommand: The command.
• eventData CommandEventData: Contextual information about the command and execution.
• result InterceptionResult<object>: Represents the current result if one exists. This value will have HasResult set to true if some previous interceptor suppressed execution by calling SuppressWithResult(TResult). This value is typically used as the return value for the implementation of this method.
• cancellationToken CancellationToken: A CancellationToken to observe while waiting for the task to complete.

Returns: ValueTask<InterceptionResult<object>>: If HasResult is false, the EF will continue as normal. If HasResult is true, then EF will suppress the operation it was about to perform and use Result instead. An implementation of this method for any interceptor that is not attempting to change the result is to return the result value passed in, often using FromResult<TResult>(TResult)

Exceptions:

• OperationCanceledException: If the CancellationToken is canceled.