Dynamo Stream Diff

[![Build Status][ci-img]][ci] [![Coverage Status][cov-img]][cov]

Allows comparing of new and old images from dynamo stream records. Note, this only works on Dynamo Streams with
a StreamViewType of NEW_AND_OLD_IMAGES

Installation


npm install dynamo-stream-diff --save


Usage

`javascript const dynamoStreamDiff = require('dynamo-stream-diff')

module.exports.handler = function(event, context, callback) { event.Records.forEach( (streamRecord) => { let diff = dynamoStreamDiff(streamRecord) // .... do something with the difference }) callback(null, "Successfully handled all the differences") }

`Example Input & Output`

`$3`

json
{
  "awsRegion": "us-west-2",
  "dynamodb": {
    "ApproximateCreationDateTime": 123456789,
    "Keys": {
      "id" : {
        "S": "abc"
      }
    },
    "NewImage": {
      "id" : {
        "S": "abc"
      },
      "name" : {
        "S": "new-name"
      },
      "size" : {
        "N": 456
      },
      "enabled" : {
        "BOOL": true
      }
    },
    "OldImage": {
      "id" : {
        "S": "abc"
      },
      "name" : {
        "S": "old-name"
      },
      "size" : {
        "N": 123
      },
      "enabled" : {
        "BOOL": false
      }
    },
    "SequenceNumber": "seq-num",
    "SizeBytes": 1245,
    "StreamViewType": "NEW_AND_OLD_IMAGES"
  },
  "eventID": "event-id",
  "eventName": "MODIFY",
  "eventSource": "event-source",
  "eventVersion": "event-version"
}

$3

`json { "diffMap": { "id": { "type": "unchanged", "oldVal": "abc", "newVal": "abc" }, "name": { "type": "updated", "oldVal": "old-name", "newVal": "new-name" }, "size": { "type": "updated", "oldVal": 123, "newVal": 456 }, "enabled": { "type": "updated", "oldVal": false, "newVal": true } }, "diffList": [ { "path": "name", "diff": "updated", "oldVal": "old-name", "newVal": "new-name" }, { "path": "size", "diff": "updated", "oldVal": 123, "newVal": 456 }, { "path": "enabled", "diff": "updated", "oldVal": false, "newVal": true } ] }``

[ci-img]: https://travis-ci.org/Nordstrom/dynamo-stream-diff.svg?branch=master
[ci]: https://travis-ci.org/Nordstrom/dynamo-stream-diff
[cov-img]: https://coveralls.io/repos/github/Nordstrom/dynamo-stream-diff/badge.svg?branch=master
[cov]: https://coveralls.io/github/Nordstrom/dynamo-stream-diff?branch=master

Installation

npm install dynamo-stream-diff --save

Usage

javascript
const dynamoStreamDiff = require('dynamo-stream-diff')

module.exports.handler = function(event, context, callback) {
  event.Records.forEach( (streamRecord) => {
    let diff = dynamoStreamDiff(streamRecord)
    // .... do something with the difference
  
  })
  callback(null, "Successfully handled all the differences")
}

Example Input & Output

$3

json
{
"awsRegion": "us-west-2",
"dynamodb": {
"ApproximateCreationDateTime": 123456789,
"Keys": {
"id" : {
"S": "abc"
}
},
"NewImage": {
"id" : {
"S": "abc"
},
"name" : {
"S": "new-name"
},
"size" : {
"N": 456
},
"enabled" : {
"BOOL": true
}
},
"OldImage": {
"id" : {
"S": "abc"
},
"name" : {
"S": "old-name"
},
"size" : {
"N": 123
},
"enabled" : {
"BOOL": false
}
},
"SequenceNumber": "seq-num",
"SizeBytes": 1245,
"StreamViewType": "NEW_AND_OLD_IMAGES"
},
"eventID": "event-id",
"eventName": "MODIFY",
"eventSource": "event-source",
"eventVersion": "event-version"
}

$3

json
{
  "diffMap": {
    "id": {
      "type": "unchanged",
      "oldVal": "abc",
      "newVal": "abc"
    },
    "name": {
      "type": "updated",
      "oldVal": "old-name",
      "newVal": "new-name"
    },
    "size": {
      "type": "updated",
      "oldVal": 123,
      "newVal": 456
    },
    "enabled": {
      "type": "updated",
      "oldVal": false,
      "newVal": true
    }
  },
  "diffList": [
    {
      "path": "name",
      "diff": "updated",
      "oldVal": "old-name",
      "newVal": "new-name"
    },
    {
      "path": "size",
      "diff": "updated",
      "oldVal": 123,
      "newVal": 456
    },
    {
      "path": "enabled",
      "diff": "updated",
      "oldVal": false,
      "newVal": true
    }
  ]
}