FR: Support multiple update actions

[mikestopcontinues]

FR: Support multiple update actions

[ruicsh]

hi @mikestopcontinues, thanks for your suggestion. I have it implemented on PR #10 but don't have access to a DDB right now so I can't test one assumption, maybe you can help?

The docs are not very explicit about how the UpdateExpression should be constructed. I'm guessing it's just a simple concatenation of the different clauses starting with keywords SET/ADD/REMOVE/DELETE:

Given this input to dynoexpr:

{
  UpdateSet: { ufoo: 'ufoo - 2' },
  UpdateRemove: { rfoo: 'rbar' },
  UpdateAdd: { afoo: 'abar' },
  UpdateDelete: { dfoo: 'dbar' },
}

It would produce:

{
  UpdateExpression:
    'SET #nff12 = #nff12 - :v862c REMOVE #nff12, #n978b ADD #nb01c :ve948 DELETE #nd358 :v45cc',
  ExpressionAttributeNames: {
    '#n978b': 'rfoo',
    '#nb01c': 'afoo',
    '#nd358': 'dfoo',
    '#nff12': 'ufoo',
  },
  ExpressionAttributeValues: {
    ':v0e91': 'rbar',
    ':v45cc': 'dbar',
    ':v862c': 2,
    ':ve948': 'abar',
  },
}

Is this your understanding, too? Cheers

[mikestopcontinues]

That was my understanding as well. I'll test it today. Thanks for your help!

[mikestopcontinues]

Things are looking good! SET, REMOVE, and ADD (add for numbers) all work concatenated with a space. I was also able to get ADD (for sets) and DELETE working too, using docClient.createSet() for the value.

On that front, does it make sense to automatically wrap any arrays in createSet() when using ADD and DELETE update actions? Does that get in the way of any other behavior?

[ruicsh]

great, I'm closing this issue now as it's fixed by the PR. I've created a new issue #11 for your createSet suggestion.. if you could add an example of the expected behavior to that issue, it would be of great help

[mikestopcontinues]

Thanks again!