TXDataTenantConnectionPool Class
Connection pool component that routes each request to the database shard of the current tenant, using the routing information provided by a TAureliusTenantCatalog.
Remarks
Assign the component to the Pool property of a XData.Comp.Server.TXDataServer. On every request, the current tenant is resolved from the ambient TTenantScope, from the ITenant context item set by Sparkle's tenant middleware, or from the catalog identifiers through the TenantLookups (the OnResolveTenant event can override that), the tenant and shard status are checked, and the connection is taken from the pool of the tenant's shard.
The application only provides the connection for each shard (OnCreateShardConnection); the component pools connections per shard, maps tenancy errors to proper HTTP responses (unknown tenant, suspended tenant, unavailable shard or catalog) and can automatically enable the multitenant global filter on every request manager (EnableFilter, FilterName, FilterParamName).
Syntax
Unit: XData.Comp.TenantConnectionPool
TXDataTenantConnectionPool = class(TXDataCustomConnectionPool, ITenantResolver);Constructors
| Name | Description |
|---|---|
| Create | Creates a new TXDataTenantConnectionPool instance. |
Methods
| Name | Description |
|---|---|
| GetPoolInterface | Returns the tenant-routing IDBConnectionPool implemented by this component. |
| GetPoolProvider | Returns the tenant-routing pool provider, for code that already knows the tenant id. |
| InvalidateAll | Drops all cached routing information and all shard connection pools. |
| InvalidateShard | Drops the cached information and the connection pool of a shard, so a fresh pool is built on next use. |
| InvalidateTenant | Drops the cached routing information of a tenant, so the next request re-reads the catalog. |
| ReleasePoolInterface | Releases the internally cached pool objects. They are recreated on next use. |
| SetupModule | Subscribes the tenancy behavior to the events of an XData server module. |
| UpdateShardSchemas | Overloaded UpdateShardSchemas UpdateShardSchemas() |
Properties
| Name | Description |
|---|---|
| AntiEnumeration | Indicates whether requests for existing but inactive tenants are answered with the same 404 response as unknown tenants. |
| Catalog | The tenant catalog component providing tenant-to-shard routing information. |
| CleanupTimeout | Gets or sets the time, in milliseconds, after which idle pooled connections are destroyed. |
| EnableFilter | Indicates whether the multitenant global filter is enabled automatically on every request manager. |
| FilterName | Gets or sets the name of the global filter enabled on request managers when EnableFilter is True. |
| FilterParamName | Gets or sets the name of the filter parameter that receives the current tenant id. |
| HandleTenant​Exceptions | Indicates whether tenancy exceptions are automatically mapped to HTTP error responses. |
| PoolSize | Gets or sets the maximum number of pooled connections per shard. |
| TenantLookups | Lookups that resolve the tenant of a request from the identifiers registered in the catalog. |
Events
| Name | Description |
|---|---|
| OnCreateShard​Connection | Fired when a database connection must be created for a shard. |
| OnCreateShardPool | Fired when a connection pool must be created for a shard, allowing full control over pool creation. |
| OnDBConnection​Release | Fired whenever a connection is released back to a shard pool. |
| OnResolveTenant | Fired after the tenant id is resolved for the current request, allowing the handler to override or augment the resolution. |