Line data    Source code

       1              : import * as arrow from 'apache-arrow';
       2              : import * as dashql from '@ankoh/dashql-core';
       3              : 
       4              : import { catalogTablesFromPgAttribute, pgAttributeQuery, type PgAttributeColumnsTable } from '../connections/catalog/catalog_query_pg_attribute.js';
       5              : import { DEFAULT_DATABASE_NAME, packCatalogTable, packRelationName, readRelationName } from '../connections/catalog/catalog_sql_generator.js';
       6              : 
       7            1 : const LAYER = dashql.buffers.catalog.CatalogLayer.CONNECTION;
       8              : 
       9              : /// The catalog of a shell on an embedded database. Its descriptor holds what the database reports.
      10            1 : export class EmbeddedDatabaseCatalog {
      11              :     /// The catalog entry of the descriptor
      12            1 :     private readonly entryId: number;
      13              : 
      14            1 :     constructor(
      15            1 :         private readonly core: dashql.DashQL,
      16            1 :         private readonly catalog: dashql.DashQLCatalog,
      17            1 :         private readonly query: (text: string) => Promise<arrow.Table>,
      18            1 :     ) {
      19            1 :         this.entryId = catalog.allocateEntryId();
      20            1 :     }
      21              : 
      22              :     /// Ask the database about what a statement touched, before the prompt returns. Also after a failure: a statement of
      23              :     /// many may have run.
      24            1 :     async afterStatement(statement: string): Promise<void> {
      25            1 :         const relations = this.core.touchedRelations(statement).map(name => readRelationName(name, DEFAULT_DATABASE_NAME));
      26            1 :         for (const databaseName of new Set(relations.map(relation => relation.databaseName))) {
      27            1 :             const ofDatabase = relations.filter(relation => relation.databaseName === databaseName);
      28            1 :             const queryDatabaseName = databaseName === DEFAULT_DATABASE_NAME ? null : databaseName;
      29            1 :             const rows = await this.query(pgAttributeQuery({ queryDatabaseName, relations: ofDatabase })) as PgAttributeColumnsTable;
      30            1 :             const tables = catalogTablesFromPgAttribute(rows, databaseName);
      31            1 :             this.catalog.replaceTables(this.entryId, LAYER, { relations: ofDatabase.map(packRelationName), tables: tables.map(packCatalogTable) });
      32            1 :         }
      33            1 :     }
      34              : 
      35            1 :     destroy(): void {
      36            1 :         this.catalog.dropDescriptor(this.entryId);
      37            1 :     }
      38            1 : }