Class DataAccessLayer

Main Data Access Layer class for PostgreSQL

Provides connection management, transaction support, and model creation functionality. This class serves as the main interface between the application and the PostgreSQL database.

Implements

DataAccessLayer

Index

Constructors

constructor

new DataAccessLayer(
config?: Partial<PostgresConfig> & JsonObject,
): DataAccessLayer
Parameters
- config: Partial<PostgresConfig> & JsonObject = {}
Returns DataAccessLayer
- Defined in dal/lib/data-access-layer.ts:47

Properties

config

config: DataAccessLayerConfig

mlString

mlString: MlStringVariants = mlString

modelRegistry

modelRegistry: ModelRegistry

pool

pool: Pool

revision

revision: RevisionHelpers = revision

`Optional`schemaNamespace

schemaNamespace?: string

types

types: {
    any: (options?: Record<string, unknown>) => Type<unknown, false>;
    array: <TElementField extends SchemaFieldLike = Type<unknown, false>>(
        elementType?: TElementField,
        options?: Record<string, unknown>,
    ) => ArrayType<TElementField, false>;
    boolean: (options?: Record<string, unknown>) => BooleanType<false>;
    date: (options?: Record<string, unknown>) => DateType<false>;
    number: (options?: Record<string, unknown>) => NumberType<false>;
    object: (options?: Record<string, unknown>) => ObjectType<unknown, false>;
    string: (options?: Record<string, unknown>) => StringType<false>;
    virtual: <TValue = unknown>(
        options?: Record<string, unknown>,
    ) => VirtualType<TValue, false>;
} = types

Methods

connect

connect(): Promise<DataAccessLayer>
Initialize the connection pool and connect to PostgreSQL

Returns Promise<DataAccessLayer>
This instance for chaining
Implementation of DataAccessLayer.connect
- Defined in dal/lib/data-access-layer.ts:73

createModel

createModel<TData extends JsonObject, TVirtual extends JsonObject = JsonObject>(
    name: string,
    schema: ModelSchema<TData, TVirtual>,
    options?: JsonObject,
): ModelConstructor<TData, TVirtual>
Create a new model class
Type Parameters
- TData extends JsonObject
- TVirtual extends JsonObject = JsonObject
Parameters
- name: string
  Model name (table name)
- schema: ModelSchema<TData, TVirtual>
  Model schema definition
- options: JsonObject = {}
  Model options
Returns ModelConstructor<TData, TVirtual>
Model constructor
Implementation of DataAccessLayer.createModel
- Defined in dal/lib/data-access-layer.ts:204

disconnect

disconnect(): Promise<void>
Close all connections and clean up

Returns Promise<void>
Implementation of DataAccessLayer.disconnect
- Defined in dal/lib/data-access-layer.ts:112

getConnection

getConnection(): Promise<PoolClient>
Get a connection from the pool

Returns Promise<PoolClient>
PostgreSQL client connection
- Defined in dal/lib/data-access-layer.ts:126

getModel

getModel<
    TData extends JsonObject = JsonObject,
    TVirtual extends JsonObject = JsonObject,
>(
    name: string,
): ModelConstructor<TData, TVirtual>
Get an existing model by name
Type Parameters
- TData extends JsonObject = JsonObject
- TVirtual extends JsonObject = JsonObject
Parameters
- name: string
  Model name
Returns ModelConstructor<TData, TVirtual>
Model constructor
Implementation of DataAccessLayer.getModel
- Defined in dal/lib/data-access-layer.ts:232

getModelRegistry

getModelRegistry(): ModelRegistry
Expose the registry instance for advanced consumers

Returns ModelRegistry
Implementation of DataAccessLayer.getModelRegistry
- Defined in dal/lib/data-access-layer.ts:252

getPoolStats

getPoolStats(): { idleCount: number; totalCount: number; waitingCount: number }
Get pool statistics

Returns { idleCount: number; totalCount: number; waitingCount: number }
- Defined in dal/lib/data-access-layer.ts:363

getRegisteredModels

getRegisteredModels(): Map<
    string,
    ModelConstructor<
        JsonObject,
        JsonObject,
        ModelInstance<JsonObject, JsonObject>,
        string,
    >,
>
Return a map of registered models keyed by canonical name

Returns Map<
    string,
    ModelConstructor<
        JsonObject,
        JsonObject,
        ModelInstance<JsonObject, JsonObject>,
        string,
    >,
>
Implementation of DataAccessLayer.getRegisteredModels
- Defined in dal/lib/data-access-layer.ts:245

isConnected

isConnected(): boolean
Check if the DAL is connected

Returns boolean
- Defined in dal/lib/data-access-layer.ts:356

migrate

migrate(migrationsPath?: string): Promise<void>
Run database migrations
Parameters
- migrationsPath: string = 'migrations'
  Path to migration files
Returns Promise<void>
Implementation of DataAccessLayer.migrate
- Defined in dal/lib/data-access-layer.ts:260

query

query<TRecord extends JsonObject = JsonObject>(
    text: string,
    params?: unknown[],
    client?: PoolLike,
): Promise<QueryResult<TRecord>>
Execute a query with optional parameters
Type Parameters
- TRecord extends JsonObject = JsonObject
Parameters
- text: string
  SQL query text
- params: unknown[] = []
  Query parameters
- client: PoolLike = null
  Optional client connection (for transactions)
Returns Promise<QueryResult<TRecord>>
Query result
Implementation of DataAccessLayer.query
- Defined in dal/lib/data-access-layer.ts:140

rollback

rollback(migrationsPath?: string): Promise<void>
Rollback the last migration (if supported)
Parameters
- migrationsPath: string = 'migrations'
Returns Promise<void>
Implementation of DataAccessLayer.rollback
- Defined in dal/lib/data-access-layer.ts:313

transaction

transaction<T>(callback: (client: PoolClient) => Promise<T>): Promise<T>
Execute a transaction with automatic rollback on error
Type Parameters
- T
Parameters
- callback: (client: PoolClient) => Promise<T>
  Function to execute within transaction
Returns Promise<T>
Result of the callback function
- Defined in dal/lib/data-access-layer.ts:174

Class DataAccessLayer

Implements

Index

Constructors

Properties

Methods

Constructors

constructor

Parameters

Returns DataAccessLayer

Properties

config

mlString

modelRegistry

pool

revision

OptionalschemaNamespace

types

Methods

connect

Returns Promise<DataAccessLayer>

createModel

Type Parameters

Parameters

Returns ModelConstructor<TData, TVirtual>

disconnect

Returns Promise<void>

getConnection

Returns Promise<PoolClient>

getModel

Type Parameters

Parameters

Returns ModelConstructor<TData, TVirtual>

getModelRegistry

Returns ModelRegistry

getPoolStats

Returns { idleCount: number; totalCount: number; waitingCount: number }

getRegisteredModels

Returns Map< string, ModelConstructor< JsonObject, JsonObject, ModelInstance<JsonObject, JsonObject>, string, >,>

isConnected

Returns boolean

migrate

Parameters

Returns Promise<void>

query

Type Parameters

Parameters

Returns Promise<QueryResult<TRecord>>

rollback

Parameters

Returns Promise<void>

transaction

Type Parameters

Parameters

Returns Promise<T>

Settings

On This Page

`Optional`schemaNamespace

Returns Map<
string,
ModelConstructor<
JsonObject,
JsonObject,
ModelInstance<JsonObject, JsonObject>,
string,
>,
>