Fixing Duplicate ID Errors with typeorm-factory

When creating a factory with typeorm-factory, you have to make sure any dynamic data is handled within a closure, otherwise it'll only run once when the factory is imported.

1const PerkCategoryFactory = new Factory(PerkCategory)
2  .attr('name', faker.lorem.word());

If you define a factory like the above, the faker.lorem.word() will only run once, when the factory is imported. This means if you were expecting a random word for each instance the factory creates, you won't get it. Instead, each factory will have the exact same word.

To fix this, you must use a sequence instead of attr:

1const PerkCategoryFactory = new Factory(PerkCategory)
2  .sequence('name', () => faker.lorem.word());

The sequence will accept a closure as the second argument, which will be invoked whenever the factory creates a new instance.

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