Assessing the Upgrade Complexity with the Pattern Detector

Overview

This feature allows you to check existing AEM instances for their upgradability by detecting patterns in use that:

1. Violate certain rules and are done in areas that will be affected or overwritten by the upgrade
2. Use an AEM 6.x feature or an API that is not backwards compatible on AEM 6.5 and can potentially break after upgrade.

This could serve as an assessment of the development effort that is involved in upgrading to AEM 6.5.

How to Set Up

The Pattern Detector is released separately as a one package working on any source AEM versions from 6.1 to 6.5 targeting AEM 6.5 upgrade. It can be installed using the Package Manager.

How to Use

You can use several methods to check the Pattern Detector output:

• Via the Felix Inventory console:

1. Go to the AEM Web Console by browsing to https://serveraddress:serverport/system/console/configMgr

2. Select Status - Pattern Detector as shown in the image below:

   

• Via a reactive text based or regular JSON interface
• **Via a reactive JSON lines interface, **that generates a separate JSON document in each line.

Both of these methods are detailed below:

Reactive Interface

The reactive interface allows for the processing of the violation report as soon as a suspicion is detected.

The output is currently available under 2 URLs:

1. Plain text interface
2. JSON interface

Handling the Plain Text Interface

The information in the output is formatted as a series of event entries. There are two channels - one for publishing violations and the second for publishing the current progress.

They can be obtained by using the following commands:

curl -Nsu 'admin:admin' https://localhost:4502/system/console/status-pattern-detector.txt | tee patterns-report.log | grep SUSPICION

The output will look like this:

2018-02-13T14:18:32.071+01:00 [SUSPICION] The pattern=ECU/extraneous.content.usage was found by detector=ContentAccessDetector with id=a07fd94318f12312c165e06d890cbd3c2c8b8dad0c030663db8b4c800dd7c33f message="Cross-boundary overlay of internal marked path /libs/granite/operations/components/commons/commons.jsp/jcr:content referenced at /apps/granite/operations/components/commons/commons.jsp/jcr:content with properties redefined: jcr:lastModifiedBy, jcr:mimeType, jcr:data, jcr:lastModified, jcr:uuid". More info at=https://www.adobe.com/go/aem6_EC

The progress can be filtered using the grep command:

curl -Nsu 'admin:admin' https://localhost:4502/system/console/status-pattern-detector.txt | tee patterns-report.log | grep PROGRESS

Which results in the following output:

2018-02-13T14:19:26.909+01:00 [PROGRESS] emitted=127731/52 MB patterns (from=6.5), analysed=45780/16 MB items, found=0 suspicions so far in period=PT5.005S (throughput=34667 items/sec)
2018-02-13T14:19:31.904+01:00 [PROGRESS] emitted=127731/52 MB patterns (from=6.5), analysed=106050/39 MB items, found=0 suspicions so far in period=PT10S (throughput=23378 items/sec)
2018-02-13T14:19:35.685+01:00 [PROGRESS] Finished in period=PT13.782

Handling the JSON Interface

Similarly, JSON can be processed using the jq tool as soon as it is published.

curl -Nsu 'admin:admin' https://localhost:4502/system/console/status-pattern-detector.json | tee patterns-report.json | jq --unbuffered -C 'select(.suspicion == true)'

With the output:

{
  "timestamp": "2018-02-13T14:20:18.894+01:00",
  "suspicion": true,
  "pattern": {
    "code": "ECU",
    "type": "extraneous.content.usage",
    "detective": "ContentAccessDetector",
    "moreInfo": "https://www.adobe.com/go/aem6_ECU"
  },
  "item": {
    "id": "a07fd94318f12312c165e06d890cbd3c2c8b8dad0c030663db8b4c800dd7c33f",
    "message": "Cross-boundary overlay of internal marked path /libs/granite/operations/components/commons/commons.jsp/jcr:content referenced at /apps/granite/operations/components/commons/commons.jsp/jcr:content with properties redefined: jcr:lastModifiedBy, jcr:mimeType, jcr:data, jcr:lastModified, jcr:uuid"
  }
}

The progress is reported every 5 seconds and can fetched by excluding other messages than those marked as suspicions:

curl -Nsu 'admin:admin' https://localhost:4502/system/console/status-pattern-detector.json | tee patterns-report.json | jq --unbuffered -C 'select(.suspicion == false)'

With the output:

{
  "suspicion": false,
  "timestamp": "2018-02-13T14:21:17.279+01:00",
  "type": "PROGRESS",
  "database": {
    "patternsEmitted": 127731,
    "patternsEmittedSize": "52 MB",
    "databasesEmitted": [
      "6.5"
    ]
  },
  "state": {
    "itemsAnalysed": 57209,
    "itemsAnalysedSize": "26 MB",
    "suspicionsFound": 0
  },
  "progress": {
    "elapsedTime": "PT5.003S",
    "elapsedTimeMilliseconds": 5003,
    "itemsPerSecond": 36965
  }
}
{
  "suspicion": false,
  "timestamp": "2018-02-13T14:21:22.276+01:00",
  "type": "PROGRESS",
  "database": {
    "patternsEmitted": 127731,
    "patternsEmittedSize": "52 MB",
    "databasesEmitted": [
      "6.5"
    ]
  },
  "state": {
    "itemsAnalysed": 113194,
    "itemsAnalysedSize": "46 MB",
    "suspicionsFound": 0
  },
  "progress": {
    "elapsedTime": "PT10S",
    "elapsedTimeMilliseconds": 10000,
    "itemsPerSecond": 24092
  }
}
{
  "suspicion": false,
  "timestamp": "2018-02-13T14:21:25.762+01:00",
  "type": "FINISHED",
  "database": {
    "patternsEmitted": 127731,
    "patternsEmittedSize": "52 MB",
    "databasesEmitted": [
      "6.5"
    ]
  },
  "state": {
    "itemsAnalysed": 140744,
    "itemsAnalysedSize": "63 MB",
    "suspicionsFound": 1
  },
  "progress": {
    "elapsedTime": "PT13.486S",
    "elapsedTimeMilliseconds": 13486,
    "itemsPerSecond": 19907
  }
}
{
  "suspicion": false,
  "type": "SUMMARY",
  "suspicionsFound": 1,
  "totalTime": "PT13.487S"
}

Detection scope

Currently Pattern Detector allows to check:

• OSGi bundles exports and imports mismatch
• Sling resource types and super types (with search-path content overlays) overusages
• definitions of Oak indexes (compatibility)
• VLT packages (overuse)
• rep:User nodes compatibility (in context of OAuth configuration)