0.5 Documentation Update

[coryodaniel]

0.5 Documentation Update

[coryodaniel]

• advanced

Kubernetes API resources are discovered pre-request and resource definitions are cached (configurable). This library is currently tested against k8s OpenAPI specs: 1.1x and master.

Custom Resource Definitions

Custom resources are discovered via the same mechanism as "standard" k8s resources and can be worked with as such:

Listing the Greetings from the hello operator.

operation = K8s.Client.list("hello-operator.example.com/v1", :greeting, [namespace: "default"])
{:ok, greeting} = K8s.Client.run(operation, :dev)

Multiple Clusters

Copying a workloads between two clusters:

Register a staging cluster:

staging_conn = K8s.Conn.from_file("~/.kube/config")
{:ok, staging} = K8s.Cluster.Registry.add(:staging, staging_conn)

Register a prod cluster:

prod_conn = K8s.Conn.from_service_account() # or from_file/2
{:ok, prod} = K8s.Cluster.Registry.add(:prod, staging_conn)

Get a list of all deployments in the default prod namespace:

operation = K8s.Client.list("apps/v1", :deployment, namespace: "default")
{:ok, deployments} = K8s.Client.run(operation, :prod)

Map the deployments to operations and async create on staging:

deployments
|> Enum.map(fn(deployment) -> K8s.Client.create(deployment) end)
|> K8s.Client.async(:staging)

Adding Authorization Providers

config :k8s, auth_providers: [My.Custom.Provider]

Providers are checked in order, the first to return an authorization struct wins.

Custom providers are processed before default providers.

For protocol and behavior implementation examples check out Certificate, Token, or AuthProvider here.

Performing sub-resource operations

Subresource (eviction|finalize|bindings|binding|approval|scale|status) operations are created in the same way as standard operations using K8s.Operation.build/4, K8s.Operation.build/5, or any K8s.Client function.

Getting a deployment's status:

cluster = :test
operation = K8s.Client.get("apps/v1", "deployments/status", name: "nginx", namespace: "default")
{:ok, scale} = K8s.Client.run(operation, cluster)

Getting a deployment's scale:

cluster = :test
operation = K8s.Client.get("apps/v1", "deployments/scale", [name: "nginx", namespace: "default"])
{:ok, scale} = K8s.Client.run(operation, cluster)

There are two forms for mutating subresources.

Evicting a pod with a Pod map:

cluster = :test
eviction = %{
  "apiVersion" => "policy/v1beta1",
  "kind" => "Eviction",
  "metadata" => %{
    "name" => "nginx",
  }
}

# Here we use K8s.Resource.build/4 but this k8s resource map could be built manually or retrieved from the k8s API
subject = K8s.Resource.build("v1", "Pod", "default", "nginx")
operation = K8s.Client.create(subject, eviction)
{:ok, resp} = K8s.Client.run(operation, cluster)

Evicting a pod by providing details:

cluster = :test
eviction = %{
  "apiVersion" => "policy/v1beta1",
  "kind" => "Eviction",
  "metadata" => %{
    "name" => "nginx",
  }
}

subject = K8s.Client.create("v1", "pods/eviction", [namespace: "default", name: "nginx"], eviction)
operation = K8s.Client.create(subject, eviction)
{:ok, resp} = K8s.Client.run(operation, cluster)