createConnection TypeError: Cannot read property 'type' of undefined

Issue type:

[x ] question [ ] bug report [ ] feature request [ ] documentation issue

Database system/driver:

[ ] cordova [x ] mongodb [ ] mssql [ ] mysql / mariadb [ ] oracle [ ] postgres [ ] cockroachdb [ ] sqlite [ ] sqljs [ ] react-native [ ] expo

TypeORM version:

[x ] latest [ ] @next [ ] 0.x.x (or put your version here)

Steps to reproduce or a small repository showing the problem:

export class Media {
  @ObjectIdColumn()
  public id: ObjectID;

  @Column()
  public instagramId: string;

  @Column({ enum: ['image', 'video']})
  public type: 'image' | 'video';

  @OneToOne(type => InstaLink, link => link.media)
  public link: InstaLink;

  @Column()
  public caption: string;

  @Column()
  public instagramCreatedTime: number;

  @Column()
  public images: {
    thumbnail?: IMediaImage;
    lowResolution?: IMediaImage;
    standardResolution?: IMediaImage;
  };

  @ManyToOne(type => User, user => user.media)
  public user: User;

  constructor(instagramMedia: InstagramMedia, user: User) {
    this.type = instagramMedia.type;
    this.instagramId = instagramMedia.id;
    this.caption = instagramMedia.caption.text;
    this.images = {
      thumbnail: {
        url: instagramMedia.images.thumbnail.url,
        height: instagramMedia.images.thumbnail.height,
        width: instagramMedia.images.thumbnail.width
      },
      lowResolution: {
        url: instagramMedia.images.low_resolution.url,
        height: instagramMedia.images.low_resolution.height,
        width: instagramMedia.images.low_resolution.width
      },
      standardResolution: {
        url: instagramMedia.images.standard_resolution.url,
        height: instagramMedia.images.standard_resolution.height,
        width: instagramMedia.images.standard_resolution.width
      }
    };
    this.user = user;
    this.instagramCreatedTime = parseInt(instagramMedia.created_time);
  }
}

I have this entity and when I’m creating connection i get this error :

TypeError: Cannot read property 'type' of undefined
    at new Media (/home/vrondelli/projects/tokilabs/livebio/service/src/models/media.ts:39:32)
    at EntityMetadata.create (/home/vrondelli/projects/tokilabs/livebio/service/src/metadata/EntityMetadata.ts:499:19)
    at EntityMetadataValidator.validate (/home/vrondelli/projects/tokilabs/livebio/service/src/metadata-builder/EntityMetadataValidator.ts:111:47)
    at /home/vrondelli/projects/tokilabs/livebio/service/src/metadata-builder/EntityMetadataValidator.ts:44:56
    at Array.forEach (<anonymous>)
    at EntityMetadataValidator.validateMany (/home/vrondelli/projects/tokilabs/livebio/service/src/metadata-builder/EntityMetadataValidator.ts:44:25)
    at Connection.buildMetadatas (/home/vrondelli/projects/tokilabs/livebio/service/src/connection/Connection.ts:505:33)
    at Connection.<anonymous> (/home/vrondelli/projects/tokilabs/livebio/service/src/connection/Connection.ts:189:18)
    at step (/home/vrondelli/projects/tokilabs/livebio/service/node_modules/typeorm/node_modules/tslib/tslib.js:133:27)
    at Object.next (/home/vrondelli/projects/tokilabs/livebio/service/node_modules/typeorm/node_modules/tslib/tslib.js:114:57)
    at fulfilled (/home/vrondelli/projects/tokilabs/livebio/service/node_modules/typeorm/node_modules/tslib/tslib.js:104:62)
    at <anonymous>
    at process._tickDomainCallback (internal/process/next_tick.js:228:7)
    at emitWarning (internal/process/promises.js:65:17)
    at emitPendingUnhandledRejections (internal/process/promises.js:109:11)
    at process._tickDomainCallback (internal/process/next_tick.js:229:7)

[ghost]

Well, I got your error it says you are trying to use type of undefined which probably throwing from that this.type = instagramMedia.type;

NOTE: Please do not post issues outside of typeorm’s scope.

[vlapo]

Hey @vrondelli. From docs https://typeorm.io/#/entities.

When using an entity constructor its arguments must be optional. Since ORM creates instances of entity classes when loading from the database, therefore it is not aware of your constructor arguments.

So mark your constructor arguments as optional and handle undefined values.

constructor(instagramMedia?: InstagramMedia, user?: User) {

Warning: This behavior is subject to change in next versions as it is discussed in https://github.com/typeorm/typeorm/issues/1772, https://github.com/typeorm/typeorm/pull/3845 and also https://github.com/typeorm/typeorm/pull/3910.