Graphile Relation Inputs Plugin (i.e., "Nested Mutations" Plugin for Graphile v5)

A Postgraphile Plugin to Update Nested Relations as Part of a Create or Update Mutation.

This is a port of the "Nested Mutations" plugin for Postgraphile v4. Given the ambiguity regarding the term "nested mutations" (see, e.g., Benjie's screed), I've renamed it Relation Inputs to more accurately reflect it's purpose. That is, this plugin allows you to edit related resources in a single mutation graph. Importantly, the plugin utilizes existing step plans to recursively apply mutations down the line.

Given a schema of:

type School implements Node {
  id: ID!
  name: String!

  teachers(
    after: Cursor
    before: Cursor
    condition: TeacherCondition
    first: Int
    last: Int
    offset: Int
    orderBy: [TeacherOrderBy!] = [PRIMARY_KEY_ASC]
  ): TeacherConnection!
}

type Teacher implements Node {
  id: ID!
  name: String!
  schoolId: Int!

  school: School
}

input SchoolInput {
  name: String!
  rowId: Int
}

input TeacherInput {
  name: String!
  rowId: Int
}

It adds the following fields to the Input Objects:

input TeacherInput {
  name: String!
  otherId: Int
  schoolId: Int!

  school: SchoolByMySchoolIdInput
}

input SchoolByMySchoolIdInput {
  connectById: SchoolByMySchoolIdConnectByNodeIdInput
  create: SchoolByMySchoolIdCreateInput
  deleteById: SchoolByMySchoolIdDeleteByNodeIdInput
  disconnectById: SchoolByMySchoolIdDisconnectByNodeIdInput
  updateById: SchoolByMySchoolIdUpdateByNodeIdInput
}

input SchoolByMySchoolIdConnectByNodeIdInput {
  id: ID!
}

input SchoolByMySchoolIdCreateInput {
  name: String!
  rowId: Int

  teachers: TeachersByTheirSchoolIdInput
}

input SchoolByMySchoolIdDeleteByNodeIdInput {
  id: ID!
}

input SchoolByMySchoolIdDisconnectByNodeIdInput {
  id: ID!
}

input SchoolByMySchoolIdUpdateByNodeIdInput {
  id: ID!
  patch: SchoolPatch!
}

input SchoolInput {
  name: String!

  teachers: TeachersByTheirSchoolIdInput
}

input TeachersByTheirSchoolIdInput {
  connectById: [TeachersByTheirSchoolIdConnectByNodeIdInput!]
  create: [TeachersByTheirSchoolIdCreateInput!]
  deleteById: [TeachersByTheirSchoolIdDeleteByNodeIdInput!]
  disconnectById: [TeachersByTheirSchoolIdDisconnectByNodeIdInput!]
  updateById: [TeachersByTheirSchoolIdUpdateByNodeIdInput!]
}

input TeachersByTheirSchoolIdConnectByNodeIdInput {
  id: ID!
}

input TeachersByTheirSchoolIdCreateInput {
  name: String!
  otherId: Int

  school: SchoolByMySchoolIdInput
  schoolId: Int!
}

input TeachersByTheirSchoolIdDeleteByNodeIdInput {
  id: ID!
}

input TeachersByTheirSchoolIdDisconnectByNodeIdInput {
  id: ID!
}

input TeachersByTheirSchoolIdUpdateByNodeIdInput {
  id: ID!
  patch: TeacherPatch!
}

Warning! This is a work in progress and experimental.

The Following Mutations are Currently Supported

• [x] Create
• [X] ConnectByNodeId
• [X] ConnectByUniqueKeys
• [X] UpdateByNodeId
• [X] UpdateByUniqueKeys
• [ ] DisconnectByNodeId
• [ ] DisconnectByUniqueKeys
• [ ] DeleteByNodeId
• [ ] DeleteByUniqueKeys

TODO:

• [ ] Add semantic version / changesets
• [ ] Migrate tests from version 4 library
• [ ] Make Plugin "Exportable"
• [ ] Use Behaviors ("nested:resource:update", etc.)
• [ ] Use tags (override fieldname)
• [ ] Add config options to limit complexity / recursive depth
• [ ] Publish to JSR?

Shoutout to Benjie and the entire graphile team. This is a small addition to their voluminous efforts.