Veneers

Note: veneers are ALPHA functionality and may adopt breaking changes

Concept and Design

File-Based Catalogs (FBC) are a major improvement to the imperative update graph approaches of previous versions. FBCs give operator authors a declarative and deterministic approach to defining their update graph. However, FBCs can get complex, especially as the number of releases and dependencies scale. We introduce the concept of a veneer as an approach to simplifying interacting with FBCs.

In this context, there are two components to every veneer:

  1. An arbitrary API
  2. An executable which processes #1 and produces a valid FBC.

The veneers supported by opm are:

  • the basic veneer, which provides a simplified abstraction of an FBC; and
  • the semver veneer, which provides the capability to generate an entire upgrade graph

Basic Veneer

The basic veneer is an input schema which eliminates FBC information that can be retrieved from existing registries when we process it. Users provide all components of an FBC schema, but supply only the bundle image reference for any olm.bundle objects. This results in a greatly simplified, smaller document. This approach may be attractive to operator authors who maintain existing catalogs and just want to make the job easier, or for operator authors who need to retain a channel graph which is not based on semver.

Usage

opm alpha render-veneer basic [flags] <filename>
FlagDescription
-h, –helpprints help/usage information
-o, –output the output format, can be yaml or json
–skip-tls-verifyskip TLS certificate verification for container image registries while pulling bundles
–use-httpuse plain HTTP for container image registries while pulling bundles

--skip-tls-verify and --use-http are mutually exclusive flags.

Example

In a very simple example, we define an olm.package and an olm.channel composed of two olm.bundle objects that have an image name attribute but no other attributes/properties.

---
schema: olm.package
name: example-operator
defaultChannel: stable
---
schema: olm.channel
package: example-operator
name: stable
entries:
- name: example-operator.v0.1.0
- name: example-operator.v0.2.0
  replaces: example-operator.v0.1.0
---
schema: olm.bundle
image: docker.io/example/example-operator-bundle:0.1.0
---
schema: olm.bundle
image: docker.io/example-operator-bundle:0.2.0

Using the opm alpha render-veneer basic command on this input generates the full FBC:

(click here to display full output)

(data blobs truncated with ‘… [snip] …’ for brevity)

---
defaultChannel: stable
name: example-operator
schema: olm.package
---
entries:
- name: example-operator.v0.1.0
- name: example-operator.v0.2.0
  replaces: example-operator.v0.1.0
name: stable
package: example-operator
schema: olm.channel
---
image: docker.io/example/example-operator-bundle:0.1.0
name: example-operator.v0.1.0
package: example-operator
properties:
- type: olm.gvk
  value:
    group: example.com
    kind: App
    version: v1
- type: olm.package
  value:
    packageName: example-operator
    version: 0.1.0
- type: olm.bundle.object
  value:
    data: eyJhcGlWZXJzaW9uIjoidjEiLCJraW5kIjoiU2VydmljZSIsIm1ldGFkYXRhIjp7ImNyZWF0aW9uVGltZXN0YW1wIjpudWxsLCJsYWJlbHMiOnsiY29udHJvbC1wbGFuZSI6ImNvbnRyb2xsZXItbWFuYWdlciJ9LCJuYW1lIjoiZXhhbXBsZS1vcGVyYXRvci1jb250cm9sbGVyLW1hbmFnZXItbWV0cmljcy1zZXJ2aWNlIn0sInNwZWMiOnsicG9ydHMiOlt7Im5hbWUiOiJodHRwcyIsInBvcnQiOjg0NDMsInByb3RvY29sIjoiVENQIiwidGFyZ2V0UG9ydCI6Imh0dHBzIn1dLCJzZWxlY3RvciI6eyJjb250cm9sLXBsYW5lIjoiY29udHJvbGxlci1tYW5hZ2VyIn19LCJzdGF0dXMiOnsibG9hZEJhbGFuY2VyIjp7fX19
- type: olm.bundle.object
  value:
    data: 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
- type: olm.bundle.object
  value:
    data: eyJhcGlWZXJzaW9uIjoicmJhYy5hdXRob3JpemF0aW9uLms4cy5pby92MSIsImtpbmQiOiJDbHVzdGVyUm9sZSIsIm1ldGFkYXRhIjp7ImNyZWF0aW9uVGltZXN0YW1wIjpudWxsLCJuYW1lIjoiZXhhbXBsZS1vcGVyYXRvci1tZXRyaWNzLXJlYWRlciJ9LCJydWxlcyI6W3sibm9uUmVzb3VyY2VVUkxzIjpbIi9tZXRyaWNzIl0sInZlcmJzIjpbImdldCJdfV19
- type: olm.bundle.object
  value:
    data: eyJhcGlWZXJzaW ... [snip] ... jEuMCJ9fQ==
- type: olm.bundle.object
  value:
    data: eyJhcGlWZXJzaW ... [snip] ... jEuMCJ9fQ==
relatedImages:
- image: gcr.io/kubebuilder/kube-rbac-proxy:v0.8.0
  name: ""
- image: docker.io/example/example-operator-bundle:0.1.0
  name: ""
- image: docker.io/example/example-operator:0.1.0
  name: ""
schema: olm.bundle
---
image: docker.io/example/example-operator-bundle:0.2.0
name: example-operator.v0.2.0
package: example-operator
properties:
- type: olm.gvk
  value:
    group: example.com
    kind: App
    version: v1
- type: olm.package
  value:
    packageName: example-operator
    version: 0.2.0
- type: olm.bundle.object
  value:
    data: eyJhcGlWZXJzaW9uIjoidjEiLCJraW5kIjoiU2VydmljZSIsIm1ldGFkYXRhIjp7ImNyZWF0aW9uVGltZXN0YW1wIjpudWxsLCJsYWJlbHMiOnsiY29udHJvbC1wbGFuZSI6ImNvbnRyb2xsZXItbWFuYWdlciJ9LCJuYW1lIjoiZXhhbXBsZS1vcGVyYXRvci1jb250cm9sbGVyLW1hbmFnZXItbWV0cmljcy1zZXJ2aWNlIn0sInNwZWMiOnsicG9ydHMiOlt7Im5hbWUiOiJodHRwcyIsInBvcnQiOjg0NDMsInByb3RvY29sIjoiVENQIiwidGFyZ2V0UG9ydCI6Imh0dHBzIn1dLCJzZWxlY3RvciI6eyJjb250cm9sLXBsYW5lIjoiY29udHJvbGxlci1tYW5hZ2VyIn19LCJzdGF0dXMiOnsibG9hZEJhbGFuY2VyIjp7fX19
- type: olm.bundle.object
  value:
    data: 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
- type: olm.bundle.object
  value:
    data: eyJhcGlWZXJzaW9uIjoicmJhYy5hdXRob3JpemF0aW9uLms4cy5pby92MSIsImtpbmQiOiJDbHVzdGVyUm9sZSIsIm1ldGFkYXRhIjp7ImNyZWF0aW9uVGltZXN0YW1wIjpudWxsLCJuYW1lIjoiZXhhbXBsZS1vcGVyYXRvci1tZXRyaWNzLXJlYWRlciJ9LCJydWxlcyI6W3sibm9uUmVzb3VyY2VVUkxzIjpbIi9tZXRyaWNzIl0sInZlcmJzIjpbImdldCJdfV19
- type: olm.bundle.object
  value:
    data: eyJhcGlWZXJzaW ... [snip] ... jEuMCJ9fQ==
- type: olm.bundle.object
  value:
    data: eyJhcGlWZXJzaW ... [snip] ... jEuMCJ9fQ==
relatedImages:
- image: gcr.io/kubebuilder/kube-rbac-proxy:v0.8.0
  name: ""
- image: docker.io/example/example-operator-bundle:0.2.0
  name: ""
- image: docker.io/example/example-operator:0.2.0
  name: ""
schema: olm.bundle

Semver Veneer

Since a veneer is identified as an input schema which is processed to generate a valid FBC, we can define a semver veneer as a schema which uses channel conventions to facilitate the auto-generation of channels adhering to Semantic Versioning (semver) guidelines and consistent with best practices on channel naming. This approach may be attractive to operator authors who are defining a new upgrade graph, or are already close enough to the veneer conventions to be able to adopt it (i.e. already use semver, only promote a single channel, etc.).

DISCLAIMER: since version build metadata MUST be ignored when determining version precedence when using semver, if any bundles differ only by build metadata the render attempt will generate a fatal error.

This alpha version of the semver veneer has the following goals:

  • terse grammar to minimize creation/maintenance effort
  • idempotent output
  • simple channel promotion
  • demonstration of a common type of channel maturity model
  • minor-version (Y-stream) and major-version (X-stream) versioning capabilities
  • clear mapping between input schema and output FBC attributes

Specification

Like best practices recommended channel naming, this veneer supports channel names Candidate, Fast, and Stable, in order of increasing channel stability. We leverage this relationship when calculating the default channel for the package.

GenerateMajorChannels and GenerateMinorChannels dictate whether this veneer will generate X-stream or Y-stream channels (attributes can be set independently). If omitted, only minor (Y-stream) channels will be generated.

Under each channel are a list of bundle image references which contribute to that channel. At least one channel must have bundle images.

The olm.semver cue schema is:

#Package: {
  schema: "olm.semver"

  // optional flag to control generating minor-version channels, defaults to _true_ if unspecified
  GenerateMinorChannels?: bool

  // optional flag to control generating major-version channels, defaults to _false_ if unspecified
  GenerateMajorChannels?: bool

  // optional candidate channel
  Candidate?: {
    Bundles: [...#ImageEntry]
  }

  // optional fast channel
  Fast?: {
    Bundles: [...#ImageEntry]
  }

  // optional stable channel
  Stable?: {
    Bundles: [...#ImageEntry]
  }

  #ImageEntry: {
    Image: string
  }
}

Usage

opm alpha render-veneer semver [flags] <filename>
FlagDescription
-h, –helpprints help/usage information
-o, –output the output format, can be yaml or json
–skip-tls-verifyskip TLS certificate verification for container image registries while pulling bundles
–use-httpuse plain HTTP for container image registries while pulling bundles

--skip-tls-verify and --use-http are mutually exclusive flags.

Example

With the following (hypothetical) example we define a mock bundle which has 11 versions, represented across each of the channel types:

Schema: olm.semver
GenerateMajorChannels: true
GenerateMinorChannels: true
Candidate:
  Bundles:
  - Image: quay.io/foo/olm:testoperator.v0.1.0
  - Image: quay.io/foo/olm:testoperator.v0.1.1
  - Image: quay.io/foo/olm:testoperator.v0.1.2
  - Image: quay.io/foo/olm:testoperator.v0.1.3
  - Image: quay.io/foo/olm:testoperator.v0.2.0
  - Image: quay.io/foo/olm:testoperator.v0.2.1
  - Image: quay.io/foo/olm:testoperator.v0.2.2
  - Image: quay.io/foo/olm:testoperator.v0.3.0
  - Image: quay.io/foo/olm:testoperator.v1.0.0
  - Image: quay.io/foo/olm:testoperator.v1.0.1
  - Image: quay.io/foo/olm:testoperator.v1.1.0
Fast:
  Bundles:
  - Image: quay.io/foo/olm:testoperator.v0.2.1
  - Image: quay.io/foo/olm:testoperator.v0.2.2
  - Image: quay.io/foo/olm:testoperator.v0.3.0
  - Image: quay.io/foo/olm:testoperator.v1.0.1
  - Image: quay.io/foo/olm:testoperator.v1.1.0
Stable:
  Bundles:
  - Image: quay.io/foo/olm:testoperator.v1.0.1

In this example, Candidate has the entire version range of bundles, Fast has a mix of older and more-recent versions, and Stable channel only has a single published entry.

If we set the veneer attributes

GenerateMajorChannels: true
GenerateMinorChannels: false

we generate the following major channels (filtering out olm.bundle objects):

---
defaultChannel: stable-v1
name: testoperator
schema: olm.package
---
entries:
- name: testoperator.v0.1.0
- name: testoperator.v0.1.1
- name: testoperator.v0.1.2
- name: testoperator.v0.1.3
  skips:
  - testoperator.v0.1.0
  - testoperator.v0.1.1
  - testoperator.v0.1.2
- name: testoperator.v0.2.0
- name: testoperator.v0.2.1
- name: testoperator.v0.2.2
  replaces: testoperator.v0.1.3
  skips:
  - testoperator.v0.2.0
  - testoperator.v0.2.1
- name: testoperator.v0.3.0
  replaces: testoperator.v0.2.2
name: candidate-v0
package: testoperator
schema: olm.channel
---
entries:
- name: testoperator.v1.0.0
- name: testoperator.v1.0.1
  skips:
  - testoperator.v1.0.0
- name: testoperator.v1.1.0
  replaces: testoperator.v1.0.1
name: candidate-v1
package: testoperator
schema: olm.channel
---
entries:
- name: testoperator.v0.2.1
- name: testoperator.v0.2.2
  skips:
  - testoperator.v0.2.1
- name: testoperator.v0.3.0
  replaces: testoperator.v0.2.2
name: fast-v0
package: testoperator
schema: olm.channel
---
entries:
- name: testoperator.v1.0.1
- name: testoperator.v1.1.0
  replaces: testoperator.v1.0.1
name: fast-v1
package: testoperator
schema: olm.channel
---
entries:
- name: testoperator.v1.0.1
name: stable-v1
package: testoperator
schema: olm.channel

We generated a channel for each veneer channel entity corresponding to each of the 0.#.#, 1.#.# major version ranges with skips to the head of the highest semver in a channel. We also generated a replaces edge to traverse across minor version transitions within each major channel. Finally, we generated an olm.package object, setting as default the most-stable channel head we created. This process will prefer Stable channel over Fast, over Candidate and then a higher bundle version over a lower version.
(Please note that the naming of the generated channels indicates the digits of significance for that channel. For example, fast-v1 is a decomposed channel of the fast type which contains only major versions of contributing bundles matching v1.)

For contrast, if we set the veneer attributes

GenerateMinorChannels: true
GenerateMajorChannels: false

we generate the following minor channels (again filtering out olm.bundle objects):

---
defaultChannel: stable-v1.0
name: testoperator
schema: olm.package
---
entries:
  - name: testoperator.v0.1.0
  - name: testoperator.v0.1.1
  - name: testoperator.v0.1.2
  - name: testoperator.v0.1.3
    skips:
      - testoperator.v0.1.0
      - testoperator.v0.1.1
      - testoperator.v0.1.2
name: candidate-v0.1
package: testoperator
schema: olm.channel
---
entries:
  - name: testoperator.v0.2.0
  - name: testoperator.v0.2.1
  - name: testoperator.v0.2.2
    replaces: testoperator.v0.1.3
    skips:
      - testoperator.v0.2.0
      - testoperator.v0.2.1
name: candidate-v0.2
package: testoperator
schema: olm.channel
---
entries:
  - name: testoperator.v0.3.0
    replaces: testoperator.v0.2.2
name: candidate-v0.3
package: testoperator
schema: olm.channel
---
entries:
  - name: testoperator.v1.0.0
  - name: testoperator.v1.0.1
    skips:
      - testoperator.v1.0.0
name: candidate-v1.0
package: testoperator
schema: olm.channel
---
entries:
  - name: testoperator.v1.1.0
    replaces: testoperator.v1.0.1
name: candidate-v1.1
package: testoperator
schema: olm.channel
---
entries:
  - name: testoperator.v0.2.1
  - name: testoperator.v0.2.2
    skips:
      - testoperator.v0.2.1
name: fast-v0.2
package: testoperator
schema: olm.channel
---
entries:
  - name: testoperator.v0.3.0
    replaces: testoperator.v0.2.2
name: fast-v0.3
package: testoperator
schema: olm.channel
---
entries:
  - name: testoperator.v1.0.1
name: fast-v1.0
package: testoperator
schema: olm.channel
---
entries:
  - name: testoperator.v1.1.0
    replaces: testoperator.v1.0.1
name: fast-v1.1
package: testoperator
schema: olm.channel
---
entries:
  - name: testoperator.v1.0.1
name: stable-v1.0
package: testoperator
schema: olm.channel

Here, a channel is generated for each veneer channel which differs by minor version, and each channel has a replaces edge from the predecessor channel to the next-lesser minor bundle version. Please note that at no time do we transgress across major-version boundaries with the channels, to be consistent with the semver convention for major versions, where the purpose is to make incompatible API changes.