# @imqueue/type-graphql-dependency 3.0.3 · API reference

Source: https://imqueue.org/api/type-graphql-dependency/latest/
Published: 2026-07-31
Author: @imqueue maintainers (https://github.com/imqueue)
Package: @imqueue/type-graphql-dependency 3.0.3 — generated reference, not hand-written

`@imqueue/graphql-dependency` for `type-graphql` — declare cross-service dependencies on the decorated classes you already have, instead of on raw `GraphQLObjectType` values.

The engine underneath is `@imqueue/graphql-dependency`, and the concepts are its concepts: a bulk \*\*loader\*\* per type, \*\*requirements\*\* describing which types own which, and an optional \*\*initializer\*\* that pre-fills fields the requirement filters need. What this package changes is where they are written. [DependencyFor()](https://imqueue.org/api/type-graphql-dependency/latest/type-graphql-dependency.dependencyfor/) is a class decorator, so a type's relations sit on the class that defines it, and [Dependency](https://imqueue.org/api/type-graphql-dependency/latest/type-graphql-dependency.dependency/) resolves a class back to its dependency description at request time.

## Remarks

`type-graphql` builds its schema from decorated classes, which means the `GraphQLObjectType` a class becomes does not exist while the decorators are running. Every declaration is therefore deferred: [DependencyFor()](https://imqueue.org/api/type-graphql-dependency/latest/type-graphql-dependency.dependencyfor/) registers a hook rather than wiring anything, and the hooks run once the schema is built.

\*\*Running them is the application's job.\*\* Nothing here calls them. After building the schema, pass it to every hook in [schemaHooks](https://imqueue.org/api/type-graphql-dependency/latest/type-graphql-dependency.schemahooks/) — miss that step and no dependency is ever registered, no error is raised, and the dependency fields simply stay empty:

```typescript
const schema = await buildSchema({ resolvers: [...] });

schemaHooks.forEach(hook => hook(schema));
```
Because the wiring is deferred, the mistakes it catches surface then rather than at start-up: a class that is not a GraphQL type, a relation naming a field that does not exist, a filter referring to an unknown field. All of them throw `TypeError` from inside the hook, so run the hooks during boot rather than lazily on first request.

## Example


```typescript
import {
    Dependency,
    DependencyFor,
    schemaHooks,
} from '@imqueue/type-graphql-dependency';
import { buildSchema, ObjectType } from 'type-graphql';

@DependencyFor<Partial<Consumer>>({
    require: [
        [() => ApiKey, [{ as: 'apiKeys', filter: { consumerId: 'id' } }]],
    ],
    async load(context, filter, fields) {
        const { data } = await context.consumer.listConsumer(filter, fields);

        return data;
    },
})
@ObjectType()
export class Consumer {
    // ... field definitions ...
}

// once, at boot
const schema = await buildSchema({ resolvers: [ConsumerResolver] });

schemaHooks.forEach(hook => hook(schema));

// later, in a resolver
await Dependency(Consumer).load(data, context, fields);
```

## Functions


| Function | Description |
| --- | --- |
| [DependencyFor(options)](https://imqueue.org/api/type-graphql-dependency/latest/type-graphql-dependency.dependencyfor/) | Class decorator declaring how a `type-graphql` entity is loaded and what it depends on, wiring it into `@imqueue/graphql-dependency`. |
| [onCreateSchema(handler)](https://imqueue.org/api/type-graphql-dependency/latest/type-graphql-dependency.oncreateschema/) | Registers a hook to run when the schema is created, ignoring a handler already registered. |


## Interfaces


| Interface | Description |
| --- | --- |
| [DependencyInterface](https://imqueue.org/api/type-graphql-dependency/latest/type-graphql-dependency.dependencyinterface/) | The callable [Dependency](https://imqueue.org/api/type-graphql-dependency/latest/type-graphql-dependency.dependency/) exposes: a class in, its dependency description out, plus the schema it resolves classes against. |
| [DependentTypeRelations](https://imqueue.org/api/type-graphql-dependency/latest/type-graphql-dependency.dependenttyperelations/) | One relation from the decorated class to a dependent class: where the loaded objects are attached, and how they are matched. |
| [DependsOptions](https://imqueue.org/api/type-graphql-dependency/latest/type-graphql-dependency.dependsoptions/) | What [DependencyFor()](https://imqueue.org/api/type-graphql-dependency/latest/type-graphql-dependency.dependencyfor/) declares for one class — any combination of requirements, an initializer and a loader. |


## Variables


| Variable | Description |
| --- | --- |
| [Dependency](https://imqueue.org/api/type-graphql-dependency/latest/type-graphql-dependency.dependency/) | The dependency description for a `type-graphql` class — the runtime half of this package, for loading dependencies inside a resolver. |
| [schemaHooks](https://imqueue.org/api/type-graphql-dependency/latest/type-graphql-dependency.schemahooks/) | Every deferred wiring hook registered so far, in the order it was registered. |


## Type Aliases


| Type Alias | Description |
| --- | --- |
| [CreateSchemaHook](https://imqueue.org/api/type-graphql-dependency/latest/type-graphql-dependency.createschemahook/) | A deferred piece of dependency wiring, run once the `type-graphql` schema exists and the classes it was declared against have become GraphQL types. |
| [DependentType](https://imqueue.org/api/type-graphql-dependency/latest/type-graphql-dependency.dependenttype/) | The class a requirement points at, named through a thunk. |