Drizzle Team•7mo ago

Get return-type from QueryBuilder

I do not have a connection to a DB, I just use the query-builder for SQL generation.
I try to write a simple function, that takes a querybuilder query in and should return a object of the result type, as if I have awaited a DB with the query:
(I use another db to fetch data - but I need the type from drizzle)

const playerQuery = await queryBuilder
    .select( /* doesnt need to be just a table */ )
    .from( schema.players )
    //.join(...)

const players = MockRequest( playerQuery )

export async function MockRequest<T extends MySqlSelectQueryBuilder>( query: T ): Promise<Awaited<T[]>>
{
    const untypedData = {}
    const data = untypedData as Awaited<T[]>

    return data
}

const playerQuery = await queryBuilder
    .select( /* doesnt need to be just a table */ )
    .from( schema.players )
    //.join(...)

const players = MockRequest( playerQuery )

export async function MockRequest<T extends MySqlSelectQueryBuilder>( query: T ): Promise<Awaited<T[]>>
{
    const untypedData = {}
    const data = untypedData as Awaited<T[]>

    return data
}

This is the return-type:

MySqlSelectQueryBuilderBase<MySqlSelectQueryBuilderHKT, "players", {
    id: MySqlColumn<{
        name: "id";
        tableName: "players";
        dataType: "number";
        columnType: "MySqlInt";
        data: number;
        driverParam: string | number;
        notNull: true;
        hasDefault: false;
        enumValues: undefined;
        baseColumn: never;
    }, object>;
    playerId: MySqlColumn<...>;
    firstName: MySqlColumn<...>;
    lastName: MySqlColumn<...>;
}, ... 6 more ..., {
    ...;
}>

MySqlSelectQueryBuilderBase<MySqlSelectQueryBuilderHKT, "players", {
    id: MySqlColumn<{
        name: "id";
        tableName: "players";
        dataType: "number";
        columnType: "MySqlInt";
        data: number;
        driverParam: string | number;
        notNull: true;
        hasDefault: false;
        enumValues: undefined;
        baseColumn: never;
    }, object>;
    playerId: MySqlColumn<...>;
    firstName: MySqlColumn<...>;
    lastName: MySqlColumn<...>;
}, ... 6 more ..., {
    ...;
}>

When it should be:

{
    id: number;
    playerId: number | null;
    firstName: string;
    lastName: string;
}[]

{
    id: number;
    playerId: number | null;
    firstName: string;
    lastName: string;
}[]

How do I type this correctly?

3 Replies

EliOP•7mo ago

After digging through alot of issues, i fund this: https://github.com/drizzle-team/drizzle-orm/pull/1662 So it seems not possible (yet?)

GitHub

[All] Fix: export internal types by Angelelz · Pull Request #1662 ·...

Closes #561 and closes #1319. Added index.ts to src/query-builders to allow the build script to pick it up. Added query builders to the index.ts files to all the dialects.

EliOP•7mo ago

I managed to get a hacky solution, I would be able to infer the types, such that the caller-side has no types explicitly stated

export async function MockRequest
  <T extends MySqlSelectQueryBuilder,R>
  ( qb: T )
  : Promise<R[]>
{
  const untypedData = {} // get data from somewhere else..
  const data = untypedData as R[]

  return data
}

// Ugly call:
const players = ( await MockRequest
    <
      ReturnType<typeof playerQuery.$dynamic>,
      typeof playerQuery._.result
    >
    ( playerQuery.$dynamic() )
)

export async function MockRequest
  <T extends MySqlSelectQueryBuilder,R>
  ( qb: T )
  : Promise<R[]>
{
  const untypedData = {} // get data from somewhere else..
  const data = untypedData as R[]

  return data
}

// Ugly call:
const players = ( await MockRequest
    <
      ReturnType<typeof playerQuery.$dynamic>,
      typeof playerQuery._.result
    >
    ( playerQuery.$dynamic() )
)

EliOP•7mo ago

Also related (kind of): https://github.com/drizzle-team/drizzle-orm/issues/948

GitHub

[FEATURE]: Ability to specify selected fields dynamically · Issue #...

Describe what you want I have a model on my project that fetching users from the database. Each time I need different set of fields and I would like to define a function with generics so only the e...

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Get return-type from QueryBuilder