Twisp Trigger Fibonacci

#FibonacciTwisp

This is a contrived example to demonstrate transaction triggers in Twisp.

README.md

For each touch of a record in the source table the fibonacci number corresponding to the count of touches is recorded in the derived table.

fibonacci.yml

Transform: AWS::Serverless-2016-10-31

Resources:
  Source:
    Type: Twisp::Database::Ledger
    Properties:
      Name: source
      Document:
        id: uuid
      Indexes:
        id:
          Partition:
          - id: document.id
          Properties:
            Unique: true
      Triggers:
        init:
          Events:
          - ON_INSERT
          Execute:
          - Name: insert_derived
            Action: DO_INSERT
            Where:
              Table: derived
            Document:
              id: context.source.id
              a: '1'
        fibonacci:
          Events:
          - ON_UPDATE
          Execute:
          - Name: update_derived
            Action: DO_UPDATE
            Where:
              Table: derived
              Index: derived.indexes.id
              Partition:
                id: context.source.id
            Document:
              a: 'document.fibonacci'
              fibonacci: 'document.a + document.fibonacci'
              index: 'document.index + 1'

  Derived:
    Type: Twisp::Database::Ledger
    Properties:
      Name: derived
      Document:
        id: uuid
        a: int
        fibonacci: int
        index: int
      Indexes:
        id:
          Partition:
          - id: document.id
          Properties:
            Unique: true
      References:
        source:
          Index: source.indexes.id
          Partition:
            id: document.id
          Properties:
            Unique: true

Mutation.gql

mutation insert {
  source {
    insert (
      input: {
        document: {
          id:"uuid(context.vars.uuid)"
        }
      }
    ) {
      record { id }
    }
  }  
}

mutation update($uuid:String!) {
  source {
    update (
      input: {
        index: id
        where: {
          partition: [ $uuid ]
        }
        document: {}
      }
    ) {
      records { id }
    }
  } 
}

Query.gql

query get($uuid:String!) {
  derived (
    index: id
    where: {
      partition: [ $uuid ]
    }
  ) {
    history {
      fibonacci
      index  
    } 
  }
}

variables.json

{
  "uuid": "00000000-0000-0000-0000-000000000000"
}