Support copying the most recent item to the counter table

[lpsinger]

This is #20 as a one-liner.

[dakota002]

This does not achieve the same goals I had in mind on #20. How does this handle the case for circulars? How do you see this used for versioning?

In the case of an update to a specific circular, what kind of config options would you have to pass into this to result in keeping the same circularId and bumping the version field?

[lpsinger]

In the case of an update to a specific circular, what kind of config options would you have to pass into this to result in keeping the same circularId and bumping the version field?

{
  doc,
  counterTableName: 'circulars',
  counterTableKey: {circularId: 33693 /* for example */},
  counterTableAttributeName: 'version',
  counterTableCopyItem: true,
  tableName: 'circulars_history',
  tableAttributeName: 'version',
  initialValue: 1,
}

[dakota002]

In the case of an update to a specific circular, what kind of config options would you have to pass into this to result in keeping the same circularId and bumping the version field?

{
  doc,
  counterTableName: 'circulars',
  counterTableKey: {circularId: 33693 /* for example */},
  counterTableAttributeName: 'version',
  counterTableCopyItem: true,
  tableName: 'circulars_history',
  tableAttributeName: 'version',
  initialValue: 1,
}

Ah, my use didn't swap the props around like this, I see how this could work now.

I think this is good, but there are a couple points that I think this misses:

• As a user who is updating an existing circular, I would expect the result to be that I now have 2 results in the history table: Verisons 1 (the original) and 2 (the one with the edits). If this runs on a circular without an existing verison, it will create a new entry marked as version 1 in both tables, and the original is lost. Are we assuming that we should run a script or something that will backfill all existing circulars with a version: 1 property and populate the entire history table?
• In the current tests, on adding a new item to the table, the counter table will overwrite the saved item, and only keep a copy of the latest inserted item. Is this resolved if the targeted counter table uses a sort key as well?

[lpsinger]

Are we assuming that we should run a script or something that will backfill all existing circulars with a version: 1 property and populate the entire history table?

Correct.

• In the current tests, on adding a new item to the table, the counter table will overwrite the saved item, and only keep a copy of the latest inserted item. Is this resolved if the targeted counter table uses a sort key as well?

I don't understand the question.

[dakota002]

• In the current tests, on adding a new item to the table, the counter table will overwrite the saved item, and only keep a copy of the latest inserted item. Is this resolved if the targeted counter table uses a sort key as well?

I don't understand the question.

How do you maintain the history when inserting new rows?
I added the following test locally to check what happens when multiple items are intentionally inserted to the table:

test('maintains history when new items are inserted', async () => {
  const initialID = 1
  const firstResult = await autoincrement.put({
    widgetName: 'runcible spoon',
  })
  expect(firstResult).toEqual(initialID)
  expect(await autoincrement.getLast()).toEqual(initialID)

  const secondResult = await autoincrement.put({
    widgetName: 'a new widget',
  })
  expect(secondResult).toBe(initialID + 1)
  const [widgetItems, autoincrementItems] = await Promise.all(
    ['widgets', 'autoincrement'].map(
      async (TableName) => (await doc.scan({ TableName })).Items
    )
  )
  expect(widgetItems).toEqual([
    { widgetID: 2, widgetName: 'a new widget' },
    { widgetID: 1, widgetName: 'runcible spoon' },
  ])
  expect(autoincrementItems).toEqual(
    counterTableCopyItem
      ? [
          {
            tableName: 'widgets',
            counter: 1,
            widgetName: 'runcible spoon',
          },
          {
            tableName: 'widgets',
            counter: 2,
            widgetName: 'a new widget',
          },
        ]
      : [
          {
            tableName: 'widgets',
            counter: 2,
          },
        ]
  )
})

Which fails with the following when the copy flag is true (first object missing):

counterTableCopyItem=true › dynamoDBAutoIncrement › maintains history when new items are inserted

    expect(received).toEqual(expected) // deep equality

    - Expected  - 5
    + Received  + 0

      Array [
        Object {
    -     "counter": 1,
    -     "tableName": "widgets",
    -     "widgetName": "runcible spoon",
    -   },
    -   Object {
          "counter": 2,
          "tableName": "widgets",
          "widgetName": "a new widget",
        },
      ]

      153 |           { widgetID: 1, widgetName: 'runcible spoon' },       
      154 |         ])
    > 155 |         expect(autoincrementItems).toEqual(
          |                                    ^
      156 |           counterTableCopyItem
      157 |             ? [
      158 |                 {

      at Object.<anonymous> (src/test.ts:155:36)

[lpsinger]

How do you maintain the history when inserting new rows?

Do you mean: how do you maintain history when inserting new GCN Circulars (entirely new Circulars that don't have a previous version)?

[dakota002]

How do you maintain the history when inserting new rows?

Do you mean: how do you maintain history when inserting new GCN Circulars (entirely new Circulars that don't have a previous version)?

Yes

[lpsinger]

How do you maintain the history when inserting new rows?

Do you mean: how do you maintain history when inserting new GCN Circulars (entirely new Circulars that don't have a previous version)?

Yes

Good point. I have to think about that.

[lpsinger]

Closing in favor of #20.