Doctor Dose

@Dose

Property decorator that marks a field as a dependency for Doctor to fill in.

Signature

class MyHandler {
  @Dose()
  public logger!: Logger;
}

@Dose reads the property's runtime type from reflect-metadata's design:type slot and appends an entry to the class's design:injectable array. Injection happens later, when @Inoculate (or a manual Doctor.treat(this)) walks that array.

Requirements

• The consumer's TypeScript config must have emitDecoratorMetadata: true — otherwise design:type will be undefined and @Dose throws MissingDesignTypeError.
• reflect-metadata must be imported once at the entry point — otherwise @Dose throws MissingMetadataError.

Example

@Inoculate()
class UserHandler {
  @Dose()
  public logger!: Logger;
  @Dose()
  public db!: Database;
}

Throws

• MissingMetadataError — when reflect-metadata is unavailable.
• MissingDesignTypeError — when emitDecoratorMetadata isn't enabled.

See in context

Every class in the web-app example uses @Dose — see Database.ts for multi-property injection or UserHandler.ts for a plain class that's wired up via Doctor.resolve instead of @Inoculate.

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