DT
Drizzle Team•6mo ago
Monopolo11

Generic base repository abstract class

So, I’m trying to create a base repository class to extend based on my schema definitions, thing is I’m having trouble getting the types to work, here is my example 
import type { InferSelectModel, SQL } from 'drizzle-orm';
import type { AnyPgTable } from 'drizzle-orm/pg-core';

import type { DB, DBTransaction } from './client';

export interface RepositoryOptions {
  db?: DB;
  tx?: DBTransaction;
}

/**
 * A generic base repository class for Drizzle ORM
 *
 * Note: This implementation uses type assertions in some places to work
 * around limitations in TypeScript's ability to fully type the Drizzle ORM.
 * The public API is fully typed, but internal implementations may use 'any'.
 */
export class BaseRepository<
  TTable extends AnyPgTable,
  TSelect = InferSelectModel<TTable>,
> {
  protected table: TTable;
  protected db: DB | DBTransaction;
  constructor(table: TTable, db: DB | DBTransaction) {
    this.table = table;
    this.db = db;
  }

  /**
   * Find all records matching the given criteria
   */
  async findAll(
    options: {
      limit?: number;
      offset?: number;
      orderBy?: SQL<unknown>;
      where?: SQL<unknown>;
    } = {},
  ): Promise<TSelect[]> {
    const { limit, offset, orderBy, where } = options;

    // Using any to avoid complex type issues with the query builder
    let query = this.db.select().from(this.table).$dynamic();

    if (where) {
      query = query.where(where);
    }

    if (orderBy) {
      query = query.orderBy(orderBy);
    }

    if (limit) {
      query = query.limit(limit);
    }

    if (offset) {
      query = query.offset(offset);
    }

    return query;
  }
}
import type { InferSelectModel, SQL } from 'drizzle-orm';
import type { AnyPgTable } from 'drizzle-orm/pg-core';

import type { DB, DBTransaction } from './client';

export interface RepositoryOptions {
  db?: DB;
  tx?: DBTransaction;
}

/**
 * A generic base repository class for Drizzle ORM
 *
 * Note: This implementation uses type assertions in some places to work
 * around limitations in TypeScript's ability to fully type the Drizzle ORM.
 * The public API is fully typed, but internal implementations may use 'any'.
 */
export class BaseRepository<
  TTable extends AnyPgTable,
  TSelect = InferSelectModel<TTable>,
> {
  protected table: TTable;
  protected db: DB | DBTransaction;
  constructor(table: TTable, db: DB | DBTransaction) {
    this.table = table;
    this.db = db;
  }

  /**
   * Find all records matching the given criteria
   */
  async findAll(
    options: {
      limit?: number;
      offset?: number;
      orderBy?: SQL<unknown>;
      where?: SQL<unknown>;
    } = {},
  ): Promise<TSelect[]> {
    const { limit, offset, orderBy, where } = options;

    // Using any to avoid complex type issues with the query builder
    let query = this.db.select().from(this.table).$dynamic();

    if (where) {
      query = query.where(where);
    }

    if (orderBy) {
      query = query.orderBy(orderBy);
    }

    if (limit) {
      query = query.limit(limit);
    }

    if (offset) {
      query = query.offset(offset);
    }

    return query;
  }
}
8 Replies
Monopolo11
Monopolo11OP•6mo ago
It looks like it should work but I get the following error in the this.table when creating the select 
Argument of type 'TTable' is not assignable to parameter of type 'TableLikeHasEmptySelection<TTable> extends true ? DrizzleTypeError<"Cannot reference a data-modifying statement subquery if it doesn't contain a `returning` clause"> : TTable'.
  Type 'PgTable<Required<{ schema: string | undefined; name: string; dialect: string; columns: Record<string, PgColumn<ColumnBaseConfig<ColumnDataType, string>, {}, {}>>; }>>' is not assignable to type 'TableLikeHasEmptySelection<TTable> extends true ? DrizzleTypeError<"Cannot reference a data-modifying statement subquery if it doesn't contain a `returning` clause"> : TTable'.
Argument of type 'TTable' is not assignable to parameter of type 'TableLikeHasEmptySelection<TTable> extends true ? DrizzleTypeError<"Cannot reference a data-modifying statement subquery if it doesn't contain a `returning` clause"> : TTable'.
  Type 'PgTable<Required<{ schema: string | undefined; name: string; dialect: string; columns: Record<string, PgColumn<ColumnBaseConfig<ColumnDataType, string>, {}, {}>>; }>>' is not assignable to type 'TableLikeHasEmptySelection<TTable> extends true ? DrizzleTypeError<"Cannot reference a data-modifying statement subquery if it doesn't contain a `returning` clause"> : TTable'.
Also for reference, this is how I’m getting the DB and DBTransaction types 
export const db = drizzle({
  client: psClient,
  schema,
  casing: "snake_case",
});

export type DBTransaction = Parameters<Parameters<typeof db.transaction>[0]>[0];
export type DB = typeof db;
export const db = drizzle({
  client: psClient,
  schema,
  casing: "snake_case",
});

export type DBTransaction = Parameters<Parameters<typeof db.transaction>[0]>[0];
export type DB = typeof db;
Any clues or examples on how to achieve this?
teo.villanueva
teo.villanueva•3mo ago
Hey! I'm experiencing the same type issue, did you manage to solve this?
JustWayne
JustWayne•3mo ago
dfrn
dfrn•3mo ago
I generally do this:
No description
JustWayne
JustWayne•3mo ago
@dfrn That's good for the base client type, but I think the problem is more surrounding the type to use for TTable.
JustWayne
JustWayne•3mo ago
I still have to use my own Tbl* types shown here if I switch to that DrizzleClientType definition which is shown here as the DbClient type and modified for Neon postgres (see attached).

resource2.ts

JustWayne
JustWayne•3mo ago
The point being, I still have to do 2 casts here, one for the table and one for the result. 
const result = (await db
    .select(...selecting)
    .from(table as any)
    .where(and(...conditions))
    .limit(1)) as SelectResult<R, "single", {}>[];
const result = (await db
    .select(...selecting)
    .from(table as any)
    .where(and(...conditions))
    .limit(1)) as SelectResult<R, "single", {}>[];
Monopolo11
Monopolo11OP•2mo ago
Not sure if this is what you are looking for. https://discord.com/channels/1043890932593987624/1372028149121945641/1372376611651059803 but that is what I needed in this thread

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