kodemore / amano Goto Github PK

Description

amano.VersionedItem class should automatically recognised by save, put and update commands as a versioned (event sourced) entity. Each time a write is made with a versioned item, there should be two writes:

• write to version 0
• write to version n, where n is an integer number increased every time item is persisted.

Version of the item should be kept as a part of sort-key. The following is the schema for the versioned sort-key:

{n}:{sort_key}

• n is the version number
• sort_key is the user's sort key

Every time read operation is made to a versioned item with a condition, that condition should be automatically ammended and sort key should be either added or modified in the expression to filter only for the latest version 0.

This behaviour can be easily ignored in the userland if two representations are made for the same item, one is versioned the other is a normal item.

References

• amano.VersionedItem

Test case scenarios

TBC

Description

Possible solution might be using a context to write multiple items to the table

References

• https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/transactions.html
• amano.Table

Test Cases

• Write data in a single transaction and assert changes in a table
• Make write data in a single transaction to fail and assert that table's data is unchanged
• Write data in a single transaction with a condition and assert changes in a table
• Write data in a single transaction with a condition in the way it fails and asssert table's data is unchanged

Description

Add support for PartiQL queries in amano.Table

References

• https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/ql-reference.html#ql-reference.what-is
• amano.Table

Description

Save method should consider the state of the item passed to it. If the item is in a new state, a put command should be executed. If the item is in dirty state an update command should be executed, otherwise save should return false.

Code References

• amano.Table.save
• amano._ItemState
• amano.Item._state

Scenarios for test coverage

• Save item in a new state
• Save item in a dirty state
• Save item in a clean state
• Save item with a condition in a new state
• Save item with a condition in a dirty state
• Save item with a condition in a clean state

Description

Scan method should support standard condition expression and return a cursor. Scan method should also support consistent reads and limit parameter.

References

• amano.Table.scan
• amano.condition.Condition

Test case scenarios

• Scan method with just a condition
• Scan method with a condition and limit
• Scan method with a consistent read option enabled and a condition

Description

At the moment count in cursor is calculated by retrieving all the items from dynamodb. We could optimise this behaviour by utilising ScannedCount and Count information: https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Query.html#Query.Count

Additionally we could abstract all the informations returned by dynamodb and provide it back to user.

References

• amano.Cursor.count
• amano.Cursor

Description

Add delete method to the table class with conditional deletion support.

References

• https://docs.aws.amazon.com/amazondynamodb/latest/APIReference/API_DeleteItem.html
• amano.Table

Test Cases

• Delete an existing item and query for it to ensure the item does not exist anymore
• Delete unexisting item
• Delete existing item with a passing condition
• Delete unexisting item with a condition
• Delete existing item with a failing condition

amano (0.2.0) depends on chili (>=1.7.0,<2.0.0) but there are now chili versions >2.0.0

Description

Support batch write operation. There should be three methods provided in the table batch_save and batch_delete and batch_write.

batch_save should be used to persist multiple items in the table at once

batch_delete should be used to remove multiple items from the table at once

batch_write should be capable of removing or persisting items

All of the methods above should probably support conditional statements.

References

• https://docs.aws.amazon.com/amazondynamodb/latest/APIReference/API_BatchWriteItem.html
• amano.Table
• amano.Table.batch_write