Blue-Green: Importing Product and WCMS content causing inconsistencies during roll over update.

[former_member664073]

We are trying to implement BLUE-GREEN deployments for our hybris nodes. For any classic application using database, blue-green deployments poses problems with 2 aspects

1) Schema changes - SAP's rolling cluster update solution addresses this aspect by having 2 typesystems simultaneously on the DB (https://help.sap.com/viewer/d0224eca81e249cb821f2cdf45a82ace/1811/en-US/8c455268866910149b25f7b53d1af3e1.html)

2) Data changes - The data changes (impexes present as part of projectdata/essentialdata) that are imported are common to both old and new code. How are these suggested to be addressed ?

Every release, we will have overlapping data changes on content/product catalog which is heavily dependent on code. Couple of trivial examples are shared below. But we do have a lot more scenarios where business logic is driven by data.

Examples :

• Adding a new component to existing slot of a page : I create a new component type and associate a controller to it in my new codebase. Also I am creating a new instance of it and associating it to an existing contentslot(of an existing page). With this particular change if I introduce the new node and perform a rolling update and project data import, as soon as the project data import completes, the node with old code starts failing that it cannot identify the new type.
• Replacing an existing component with a new component : I remove an existing component and replace it with a new component. This would break my page in old node, since the code changes for the replaced component are missing

So in all such cases,

Though we can build a custom solution (#1: having catalog versions as blue and green and seggregating the release changes) addressing the above use cases I am more keen to understand,

• Is there any OOB feature / hybris expert service solution to handle this?
• Alternatively, does Hybris prescribes any high level solution around this, which can be inherited and extended to address this concern ?

[samanthadonga_01]

Reply from SAP Hybris

I reviewed your concerns and sample scenarios.

To be honest, those limitations which you are concerned about are also limitations of deployments with Rolling Update. There are scenarios in which Rolling Update simply will not be possible and there is no alternate solution provided ootb.
Same limitations will apply with BLUE-GREEN deployments when System Update or advanced componentens modifications are part of such deployment.

To the extent of my knowledge and what I was able to check now, there is no extra solution which our Expert Services (currently Field Services) could provide. Dedicated Field Services could provide guidance or help implementing such solution but from what I understood it's not what you meant.
Incase you decide to reach out to Fiels Services please be aware that their assistance is a charged service.

If you want to introduce a completely zero downtime deployments to your system then you need to work on custom solution. Having dedicated BLUE-GREEN catalog versions seems reasonable.

I hope that my expalanation clarifies some aspects for you.

Kind regards,
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