kysely
Version:
Type safe SQL query builder
51 lines (50 loc) • 2.2 kB
TypeScript
import { QueryResult } from '../driver/database-connection.js';
import { RootOperationNode } from '../query-compiler/query-compiler.js';
import { QueryId } from '../util/query-id.js';
import { UnknownRow } from '../util/type-utils.js';
export interface KyselyPlugin {
/**
* This is called for each query before it is executed. You can modify the query by
* transforming its {@link OperationNode} tree provided in {@link PluginTransformQueryArgs.node | args.node}
* and returning the transformed tree. You'd usually want to use an {@link OperationNodeTransformer}
* for this.
*
* If you need to pass some query-related data between this method and `transformResult` you
* can use a `WeakMap` with {@link PluginTransformQueryArgs.queryId | args.queryId} as the key:
*
* ```ts
* const plugin = {
* data: new WeakMap<QueryId, SomeData>(),
*
* transformQuery(args: PluginTransformQueryArgs): RootOperationNode {
* this.data.set(args.queryId, something)
* return args.node
* },
*
* transformResult(args: PluginTransformResultArgs): QueryResult<UnknownRow> {
* const data = this.data.get(args.queryId)
* return args.result
* }
* }
* ```
*
* You should use a `WeakMap` instead of a `Map` or some other strong references because `transformQuery`
* is not always matched by a call to `transformResult` which would leave orphaned items in the map
* and cause a memory leak.
*/
transformQuery(args: PluginTransformQueryArgs): RootOperationNode;
/**
* This method is called for each query after it has been executed. The result
* of the query can be accessed through {@link PluginTransformResultArgs.result | args.result}.
* You can modify the result and return the modifier result.
*/
transformResult(args: PluginTransformResultArgs): Promise<QueryResult<UnknownRow>>;
}
export interface PluginTransformQueryArgs {
readonly queryId: QueryId;
readonly node: RootOperationNode;
}
export interface PluginTransformResultArgs {
readonly queryId: QueryId;
readonly result: QueryResult<UnknownRow>;
}