Build a platform with KRM: Part 1 – What’s in a platform?

That is the primary submit in a multi-part collection on constructing developer platforms with the Kubernetes Useful resource Mannequin (KRM). 

In at the moment’s digital world, it’s extra necessary than ever for organizations to rapidly develop and land options, scale up, get better quick throughout outages, and do all this in a safe, compliant manner. In case you’re a developer, system admin, or safety admin, you realize that it takes rather a lot to make all that occur, together with a tradition of collaboration and belief between engineering and ops groups. 

However constructing tradition isn’t nearly communication and shared values— it’s additionally about instruments. When software builders have the instruments and company to code, with sufficient abstraction to concentrate on constructing options, they’ll construct quick with out getting slowed down in infrastructure. When safety admins have streamlined processes for creating and auditing insurance policies, engineering groups can preserve constructing with out ready for safety opinions. And when service operators have highly effective, cross-environment automation at their disposal, they’ll assist a rising enterprise with new engineering groups – with out having so as to add extra IT employees. Stated one other manner: to ship high-quality code quick and safely, you want an excellent developer platform.

What’s a platform? It’s the layers of expertise that make software program supply doable, from Git repositories and take a look at servers, to firewall guidelines and CI/CD pipelines, to specialised instruments for analytics and monitoring, to the manufacturing infrastructure that runs the software program itself.  

A corporation’s platform wants rely upon a wide range of components, corresponding to industry vertical, measurement, and safety necessities. Some organizations can get by with a fully-managed Platform as a Service (PaaS) like Google App Engine, and others want to construct their platform in-house. At Google Cloud, we serve a number of clients who fall someplace within the center: they need extra customization (and fewer lock-in) than what’s offered by an all-in-one PaaS, however they’ve neither the time nor assets to construct their very own platform from scratch. These clients could come to Google Cloud with established tech preferences and targets. For instance, they could need to undertake Serverless however not Service Mesh, or vice versa. A corporation on this class would possibly flip to a supplier like Google Cloud to make use of a mix of hosted infrastructure and companies, as proven within the diagram beneath.

However a platform isn’t only a mixture of merchandise. It’s the APIs, UIs, and command-line instruments you utilize to work together with these merchandise, the integrations and glue between them, and the configuration that lets you create environments in a repeatable manner. In case you’ve ever tried to work together with a number of assets directly, or handle them on behalf of engineering groups, you realize that there’s rather a lot to maintain observe of. So what else goes right into a platform? 

For starters, a platform must be human-friendly, with abstractions relying on the person. Within the diagram above, for instance, the app developer focuses on writing and committing supply code. Any lower-level infrastructure entry might be restricted to what they care about: for example, spinning up a growth setting. A platform must also be scalable: extra assets ought to have the ability to be “stamped out” in an automatic, repeatable manner. A platform must be extensible, permitting an org so as to add new merchandise to that diagram as their enterprise and expertise wants evolve. Lastly, a platform must be safe, compliant to industry- and location-specific rules. 

So how do you get from a group of infrastructure to a well-abstracted, scalable, extensible, safe, platform? 

You’ll see that one product icon in that diagram is Google Kubernetes Engine (GKE), a container orchestration software primarily based on the open-source Kubernetes venture. Whereas Kubernetes is firstly a “compute” software, that’s not all it might probably do. 

Kubernetes is exclusive due to its declarative design, permitting builders to declare their intent and let the Kubernetes management airplane take motion to “make it so.” The Kubernetes Useful resource Mannequin (KRM) is the declarative format you utilize to speak to the Kubernetes API. Typically, KRM is expressed as YAML, just like the file proven beneath.

In case you’ve ever run “kubectl apply” on a Deployment useful resource just like the one above, you realize that Kubernetes takes care of deploying the containers inside Pods, scheduling them onto Nodes in your cluster. And you realize that when you attempt to manually delete the Pods, the Kubernetes management airplane will convey them again up- it nonetheless is aware of about your intent, that you really want three copies of your “helloworld” container. The job of Kubernetes is to reconcile your intent with the operating state of its resources- not simply as soon as, however constantly.  

So how does this relate to platforms, and to the opposite merchandise in that diagram? As a result of deploying and scaling containers is barely the start of what the Kubernetes management airplane can do. Whereas Kubernetes has a core set of APIs, it is usually extensible, permitting builders and suppliers to construct Kubernetes controllers for their very own assets, even assets that dwell exterior of the cluster. In actual fact, practically each Google Cloud product within the diagram above— from Cloud SQL, to IAM, to Firewall Guidelines — might be managed with Kubernetes-style YAML. This enables organizations to simplify the administration of these totally different platform items, utilizing one configuration language, and one reconciliation engine. And since KRM is predicated on OpenAPI, builders can summary KRM for builders, and construct instruments and UIs on prime.

Additional, as a result of KRM is usually expressed in a YAML file, customers can retailer their KRM in Git and sync it right down to a number of clusters directly, permitting for simple scaling, in addition to repeatability, reliability, and elevated management. With KRM instruments, you may guarantee that your safety insurance policies are at all times current in your clusters, even when they get manually deleted. 

Briefly, Kubernetes isn’t just the “compute” block in a platform diagram – it will also be the highly effective declarative management airplane that manages massive swaths of your platform. Finally, KRM can get you many large steps nearer to a developer platform that helps you ship software program quick, and securely. 

The remainder of this collection will use concrete examples, with accompanying demos, to indicate you how one can construct a platform with the Kubernetes Useful resource Mannequin. Head over to the GitHub repository to observe Half 1 – Setup, which can spin up a pattern GKE setting in your Google Cloud venture. 

And keep tuned for Half 2, the place we’ll dive into how the Kubernetes Useful resource Mannequin works.