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Gregory Nickonov edited this page Mar 12, 2019 · 19 revisions

Quick Start

R.deployment :backend do
  container do
    image 'tutum/hello-world'
  end
end

Sets up main container of deployment with tutum/hello-world image.

Container

Kubernetes Documentation

Property Kubernetes property Type
args args Array of String
command command Array of String
env env Array of EnvVar
env_from envFrom Array of EnvFromSource
image image String
image_pull_policy imagePullPolicy String
TODO: lifecycle lifecycle Lifecycle
liveness_probe livenessProbe Probe
name name String
ports ports Array of ContainerPort
readiness_probe readinessProbe Probe
TODO: resources resources ResourceRequirements
TODO: security_context securityContext SecurityContext
stdin stdin Boolean
stdin_once stdinOnce Boolean
termination_message_path terminationMessagePath String
termination_message_policy terminationMessagePolicy String
tty tty Boolean
TODO: volume_devices volumeDevices Array of VolumeDevice
volume_mounts volumeMounts Array of VolumeMount
working_dir workingDir String

args

Passing list of values adds them to the args array:

R.deployment :backend do
  container do
    args '-v', '1', '-l', 42
  end
end

command

Passing list of values adds them to the command array:

R.deployment :backend do
  container do
    command '/bin/sh', '-c', 'ls -al'
  end
end

environment

A complex helper to manipulate container's environment-oriented properties: env and env_from.

add

Kubernetes Documentation

Key-value pairs passed to add are converted into name and value properties of EnvVar objects and added to env array:

R.deployment :backend do
  container do
    environment do
      add DB_NAME: 'backend', DB_USER: 'postgres'
    end
  end
end

add_config_map_key

Kubernetes Documentation

Adds a specified key from the specified ConfigMap as an environment variable with the specified name to the env array:

R.scope :backend do
  R.config_map do
    set DB_NAME: 'database'
  end

  R.deployment do
    container do
      environment do
        # Adds a value of the key 'DATABASE' from the ConfigMap 'db' as an environment
        # variable 'DB_NAME' without failing if it is doesn't exists
        add_config_map_key :DB_NAME, :db, key: :DATABASE, optional: true

        # Adds a value of the key 'DB_NAME' from the ConfigMap 'backend' as an environment
        # variable 'DB_NAME' failing if it is doesn't exists
        add_config_map_key :DB_NAME, :backend, key: :DB_NAME

        # The same as above, but the ConfigMap's key name is defaulted to the environment
        # variable name (which is 'DB_NAME')
        add_config_map_key :DB_NAME, :backend

        # The same as above, but the ConfigMap's key name is defaulted to the environment
        # variable name (which is 'DB_NAME') and the name of the ConfigMap itself is defaulted
        # to the name of the current scope (which is 'backend')
        add_config_map_key :DB_NAME
      end
    end
  end
end

add_secret_key

Kubernetes Documentation

Adds a specified key from the specified Secret as an environment variable with the specified name to the env array:

R.scope :backend do
  R.secret do
    set DB_PASSWORD: 'supersecret'
  end

  R.deployment do
    container do
      environment do
        # Adds a value of the key 'PASSWORD' from the Secret 'db' as an environment
        # variable 'DB_PASSWORD' without failing if it is doesn't exists
        add_secret_key :DB_PASSWORD, :db, key: :PASSWORD, optional: true

        # Adds a value of the key 'DB_PASSWORD' from the Secret 'backend' as an environment
        # variable 'DB_PASSWORD' failing if it is doesn't exists
        add_secret_key :DB_PASSWORD, :backend, key: :DB_PASSWORD

        # The same as above, but the ConfigMap's key name is defaulted to the environment
        # variable name (which is 'DB_PASSWORD')
        add_secret_key :DB_PASSWORD, :backend

        # The same as above, but the ConfigMap's key name is defaulted to the environment
        # variable name (which is 'DB_PASSWORD') and the name of the ConfigMap itself is defaulted
        # to the name of the current scope (which is 'backend')
        add_secret_key :DB_PASSWORD
      end
    end
  end
end

add_field

Kubernetes Documentation

Adds an environment variable with the reference to the property of the current object to the env array:

R.deployment :backend do
  container do
    environment do
      add_field :KUBERNETES_POD_NAME, 'metadata.name'
    end
  end
end

There is an optional last argument, api_version which can be used to alter the version of the schema the field path is written in terms of.

add_resource_field

Kubernetes Documentation

Adds an environment variable with the reference to the current (or specified) container's resource field to the env array:

R.deployment :backend do
  container do
    environment do
      # Reference resource field from the same container
      add_resource_field :KUBERNETES_MEMORY_LIMITS, 'limits.memory'
    end
  end

  container :sidecar do
    environment do
      # Reference resource field from the main container with the divisor 1m
      add_resource_field :KUBERNETES_CPU_REQUESTS, 'requests.cpu',
                         container_name: :main, divisor: '1m'
    end
  end
end

use_config_map

Kubernetes Documentation

Adds a reference to the specified ConfigMap to the env_from array:

R.scope :backend do
  R.config_map do
    set DEBUG: 'true'
  end

  R.deployment do
    container do
      environment do
        # Reference 'backend' ConfigMap
        use_config_map :backend

        # Reference ConfigMap with the same name as the current scope
        use_config_map

        # Reference 'diagnostics' ConfigMap, prefix all keys with 'DIAGNOSTICS_' and
        # do not fail, if that ConfigMap is doesn't exists
        use_config_map :diagnostics, optional: true, prefix: 'DIAGNOSTICS_'
      end
    end
  end
end

use_secret

Kubernetes Documentation

Adds a reference to the specified Secret to the env_from array:

R.scope :backend do
  R.secret do
    set ROOT_PASSWORD: 'supersecret'
  end

  R.deployment do
    container do
      environment do
        # Reference 'backend' Secret
        use_secret :backend

        # Reference Secret with the same name as the current scope
        use_secret

        # Reference 's3' Secret, prefix all keys with 'S3_' and
        # do not fail, if that Secret is doesn't exists
        use_secret :s3, optional: true, prefix: 'S3_'
      end
    end
  end
end

expose_port

Adds a port information to the ports array:

R.deployment :backend do
  container do
    expose_port 80, host_ip: '0.0.0.0', host_port: 8080, name: :http, protocol: :TCP
  end
end

expose_default_http_port

A shortcut for exposing container's port 80 with the name 'http:

R.deployment :backend do
  container do
    expose_default_http_port
  end
end

image

With arguments passed sets image and optionally sets image pull policy for the container:

R.deployment :backend do
  container do
    # Specify image 
    image 'myregistry.com/backend:latest'

    # Specify image and image pull policy
    image 'myregistry.com/backend:latest', :IfNotExists
  end
end

mount_volume

Adds a VolumeMount with specified parameters to the volume_mounts array:

R.deployment :backend do
  container do
    # Mount volume 'appsettings' at path '/etc/config'
    mount_volume :appsettings, '/etc/config', readonly: true

    # Mount volume 'appsettings' at path '/etc/config' marking it as readonly
    mount_volume :appsettings, '/etc/config', readonly: true

    # Mount volume 'appsettings' at path '/etc/config' marking it as readonly
    mount_volume :appsettings, '/etc/config', readonly: true

    # Mount volume 'appsettings' at path '/etc/config' marking it as readonly,
    # specifying mount propagation mode and root inside the volume
    mount_volume :appsettings, '/etc/config', readonly: true,
                 mount_propagation: :MountPropagationNone, sub_path: '/data'
  end
end

ContainerPort

Kubernetes Documentation

Property Kubernetes property Type
container_port containerPort Integer
host_ip hostIP String
host_port hostPort Integer
name name String
protocol protocol String

VolumeMount

Kubernetes Documentation

Property Kubernetes property Type
mount_path mountPath String
mount_propagation mountPropagation String
name name String
readonly readOnly Boolean
sub_path subPath String

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