environment conflates logical environment with physical deployment target

[xibz]

Observation

Looking at the environment events (environmentCreated, environmentModified, environmentDeleted), the current model for an environment is:

• id: a stable identifier
• name: a human-readable label
• uri: an address pointing to the environment (created/modified only)

The presence of uri reveals the underlying assumption: an environment is treated as a physical, addressable deployment target, something like a cluster endpoint or a namespace URL. This conflates two distinct concepts:

1. Logical environment: an abstract tier in a delivery pipeline: prod, nonprod, staging. This is what most people mean when they say "environment" in
   the context of software delivery.
2. Deployment target: the concrete infrastructure being deployed to: a Kubernetes cluster, a cloud region, a namespace. This is what id + uri are actually describing.

Why this matters

These two concepts don't map 1:1:

• Multiple deployment targets can belong to the same logical environment (e.g. us-east-1-prod and eu-west-1-prod are both prod).
• A single deployment target can serve multiple logical environments depending on context (e.g. a shared cluster with prod and staging namespaces).
• Many CD tools only know one or the other, but they know which cluster they deployed to, or they know the environment label, but not both.

The current schema forces a single unified concept where there should be two, and requiring id assumes a stable identifier exists for the environment when often only a label does.

Proposal

Clarify whether environment in CDEvents is meant to represent the logical tier, the physical target, or both, and consider whether these should be separate concepts in the spec.

[davidB]

For me, environment == deployment target.

As you mention, "Logical environment" is an abstract tier, often undefined for tool, but "easily" computable from the deployment target's id (lookup table, string extraction, ...).

Environment subject.content can be extended with optional (meta)data like "logical environment" or tier (what I named audience in #309), nature (VPC, k8s cluster, swarm,.... endless list).

[xibz]

After discussion in the SIG, we discussed that what would work best is to update the definitions to include a label to a target.

Additionally, we need to match the docs, currently service.deployed, https://github.com/cdevents/spec/blob/main/continuous-deployment.md#service-deployed, says environment is an environment which is defined to have 4 fields. We only include 2 in the services. We decided that following the docs is best.