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KHoist

Compose products

A product can declare inputs from other products in the same namespace. KHoist observes that dependency graph. Your independently operated workload performs the actual queries and transformations.

Declare an input

Section titled “Declare an input”

An input chooses a product and one of its named outputs:

inputs:
  - name: observations
    productRef:
      name: harbour
      namespace: products
      output: query
    contract:
      protocol: OpenAPI
      minimumVersion: v1.1.0

The namespace defaults to the consumer’s namespace. Cross-namespace composition is rejected; discovering a product does not authorise a cross-namespace dependency.

Validate the graph

Section titled “Validate the graph”

From a source checkout:

Terminal window
PUBLISHER_PREFLIGHT_ENABLED=true go run ./cmd/product-check \
  --file docs/examples/composition.yaml

This checks a three-product example and reports the required composition feature. For a deployed graph with declared contract requirements, the operator must explicitly enable composition.enabled. A successful offline check does not enable it.

Read the result

Section titled “Read the result”

Inspect the consumer’s CompositionReady condition, aggregate Ready condition and observed lineage. Missing products or outputs, incompatible declared contracts, cycles and unavailable producers prevent readiness.

Version checks use publisher declarations: a minimum stable version within major 1 accepts compatible later stable major-1 versions. Major-zero versions require an exact match. KHoist does not fetch schemas or prove that responses have compatible semantics.

The composition reference contains the complete example, failure reasons and graph bounds.