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Reference Field

Reference to another schema, indicates that it will have one of the generated values of the selected field.

Tip

The field to reference must be a key field.

const userSchema = chaca.schema({
   id: chaca.key(chaca.sequence()),
   // rest fields
})

const postSchema = chaca.schema({
   author: chaca.ref('User.id'),
   // rest fields
})

chaca.multiGenerate([
   { name: 'User', schema: userSchema, documents: 50 },
   { name: 'Post', schema: postSchema, documents: 50 },
])

As seen in the previous code, the field will have one of the values id generated by the User schema, which can be repeated in other documents generated by the Post schema.

Try reference a ref field

If you try to reference a ref field an exception will be thrown

export const schemaOne = chaca.schema({
   id: schemas.id.uuid(),
   ref: chaca.ref('SchemaTwo.ref'), // this will throw an error because 'SchemaTwo.ref' is a ref field,
})

export const schemaTwo = chaca.schema({
   id: schemas.id.uuid(),
   ref: chaca.ref('SchemaThree.name'),
})

export const schemaThree = chaca.schema({
   id: schemas.id.uuid(),
   name: schemas.person.fullName(),
})

Config​

where​

Function that indicates if the ref document is valid.
It works as a filter for documents that do not meet a certain condition.

const postSchema = chaca.schema({
   author: chaca.ref('User.id', ({ refFields: userFields }) => {
      // will only choose the ids of users older than 18
      return userFields.age > 18
   }),
   // rest fields
})

This function receives as a parameter an object with 3 properties:

  • refFields An object with the fields created up to that point in the document that can be referenced

    const postSchema = chaca.schema({
       id: schemas.id.uuid(),
       author: chaca.ref('User.id', ({ refFields }) => {
          return refFields.age >= 18
       }),
    })

  • currentFields An object with the fields already created up to that moment

    const userSchema = chaca.schema({
       id: schemas.id.uuid(),
       favoriteCategory: chaca.enum(['Horror', 'Comedy', 'Action']),
       posts: {
          type: chaca.ref('Post.id', ({ currentFields, refFields }) => {
             return currentFields.favoriteCategory === refFields.category
          }),
          isArray: 20,
       },
    })

  • store Dataset store to interact with all the data in the dataset. Learn about Dataset Store

unique​

Indicates if the selected value can not be chosen by another documents of that schema.

const postSchema = chaca.schema({
   author: chaca.ref('User.id', { unique: true }),
   // rest fields
})