Citrix Application Delivery Management service

Parameters

This section lets you define all the parameters that you require in your StyleBook to create a configuration. It describes the input that your StyleBook takes. Although this section is optional, most StyleBook might need one. You can consider the parameters section to define the fields for the users who use the StyleBook to create a configuration on a Citrix ADC instance.

When you import your StyleBook into Citrix ADM and use it to create a configuration, the GUI uses this section of the StyleBook to display a form. This form takes an input for the defined parameter values.

The following section describes the attributes that you need to specify for each parameter in this section:

‘name’

The name of the parameter you want to define. You can specify an alphanumeric name.

The name must begin with an alphabet, and can include more alphabets, numbers, hyphen (-), or underscore (_).

When writing a StyleBook, you can use this “name” attribute to refer to the parameter in other sections by using the notation $parameters.<name>.

Mandatory? Yes

‘label’

A string that is displayed in the ADM GUI as the name of this parameter.

Mandatory? No

‘description’

A help string that describes what the parameter is used for. The ADM GUI displays this text when the user clicks the help icon for this parameter.

Mandatory? No

‘type’

The type of value these parameters can take. Parameters can be of any of the following built-in types:

  • string: An array of characters. If a length is not specified, the string value can take any number of characters. However, you can limit the length of a string type by using the attributes min-length and max-length.

  • number: An integer number. You can specify the minimum and maximum number that this type can take by using the attributes min-value and max-value.

  • boolean: Can be either true or false. YAML considers all the literals as booleans (for example, Yes or No).

  • ipaddress: A string that represents a valid IPv4 or IPv6 address.

  • tcp-port: A number between 0 and 65535 that represents a TCP or UDP port.

  • password: Represents an opaque/secret string value. When the ADM GUI displays a value for this parameter, it is shown as asterisks (*****).

  • certfile: Represents a certificate file. This value allows you to upload the files directly from your local system when you are creating a StyleBook configuration using the ADM GUI. The uploaded certificate file is stored in the directory /var/mps/tenants/\<tenant_path>/ns_ssl_certs in ADM.

    The certificate file is added to the list of certificates managed by ADM.

  • keyfile: Represents a certificate key file. This value allows you to upload the file directly from your local system when you are creating a StyleBook configuration using the ADM GUI. The uploaded certificate file is stored in the directory /var/mps/tenants/\<tenant_path>/ns_ssl_keys in ADM.

    The certificate key file is added to the list of certificate keys managed by ADM.

  • file: Represents a file.

  • object: This type is used when you want to group several related parameters under a parent element. Specify the parent parameter the type as “object”. A parameter of type “object” can have a nested “parameters” section to describe the parameters it contains.

  • another StyleBook: When you use this type of parameter, then this parameter expects its value to be in the form of the parameters defined in the StyleBook denoting its type.

A parameter can also have a type that is the list of types. To do so, add [] at the end of the type. For example, if the type attribute is string[], this parameter takes a list of strings as input. You can provide one, two, or several strings for this parameter when creating a configuration from this StyleBook.

Mandatory? Yes

‘network’

For type: ipaddress, you can specify the network attribute to auto-allocate an IP address from an ADM IPAM network.

ADM auto-allocates an IP address from the network attribute when you create a StyleBook configuration.

Example:

      name: virtual-ip
      label: "Load Balancer IP Address"
      type: ipaddress
      network: "network-1"
      required: true

In this example, the virtual-ip field auto-allocates an IP address from network-1.The IP address is released back to the network when the configuration is deleted.

‘dynamic-allocation’

The dynamic-allocation attribute is added in the parameter definition of type:ipaddress. Use this attribute to dynamically list the ADM IPAM networks. This attribute can take either true or false as an input. For type: ipaddress, specify the dynamic-allocation: true attribute to dynamically list the ADM IPAM networks that are in ADM. In the configuration pack creation form, you can do the following:

  1. Select the required IPAM network from the list.

  2. Specify an IP address that you want to allocate from the selected IPAM network.

    If no IP address is specified, the ADM auto-allocates an IP address from the selected IPAM network.

Example:

  -
    name: virtual-ip
    label: "Load Balancer IP Address"
    type: ipaddress
    dynamic-allocation: true
    required: true

In this example, the virtual-ip field lists the ADM IPAM networks that are in ADM. Select a network from the list to auto-allocate an IP address from the network. The IP address is released back to the network when the configuration is deleted.

‘key’

Specify true or false to indicate if this parameter is a key parameter for the StyleBook.

A StyleBook can have only one parameter defined as the “key” parameter.

When you create different configurations from the same StyleBook (on the same or different ADC instances), each configuration has a different/unique value for this parameter.

Default value is false.

Mandatory? No

‘required’

Specify true or false to indicate whether a parameter is mandatory or optional. If it is set to true, the parameter is mandatory and the user has to provide a value for this parameter when creating configurations.

The ADM GUI forces the user to provide a valid value for this parameter.

Default value is false.

Mandatory? No

‘allowed-values’

Use this attribute to define a list of valid values for a parameter, when the type is set to “string.”

When creating a configuration from the ADM GUI, the user is prompted to select a parameter value from this list.

Note

If you want to display the list values as radio options, set the layout attribute.

Example 1:

-
      name: ipaddress
      type: string
      allowed-values:
            -  SOURCEIP
            -  DEST IP
            -  NONE

Example 2:

-
      name: TCP Port
      type: tcp-port
      allowed-values:
            -  80
            -  81
            -  8080

Example 3:

List of tcp-ports, where each element of the list can only have values specified in allowed-values.

-
      name: tcpports
      type: tcp-port[]
      allowed-values:
            -  80
            -  81
            -  8080
            -  8081

Mandatory? No

‘default’

Use this attribute to assign a default value to an optional parameter. When a user creates a configuration without specifying a value, the default value is used.

The parameter takes no value if the following conditions are met:

  • The parameter has no default value.

  • A user does not provide a value for the parameter.

Example 1:

-
      name: timeout
      type: number
      default: 20

Example 2:

To list the default values of the parameter:

-
      name: protocols
      type: string[]
      default:
            -  TCP
            -  UDP
            -  IP

Example 3:

-
      name: timeout
      type: number
      default: 20

Example 4:

-
      name: tcpport
      type: tcp-port
      default: 20

Mandatory? No

‘pattern’

Use this attribute to define a pattern (regular expression) for the valid values of this parameter, when the type of the parameter is “string.”

Example:

-
      name: appname
      type: string
      pattern: "[a-z]+"

Mandatory? No

‘min-value’

Use this attribute to define the minimum value for parameters of type number or tcp-port.

Example:

-
      name: audio-port
      type: tcp-port
      min-value: 5000

The min-value of numbers can be negative. However, the min-value for tcp-port must be positive.

Mandatory? No

‘max-value’

Use this attribute to define the maximum value for parameters of type number or tcp-port.

Ensure the maximum value is greater than the minimum value, if defined.

Example:

-
      name: audio-port
      type: tcp-port
      min-value: 5000
      max-value: 15000

Mandatory? No

‘min-length’

Use this attribute to define the minimum length of values accepted for a parameter of type “string.”

Ensure the minimum length of the characters defined as values are greater or equal to zero.

Example:

-
      name: appname
      type: string
      min-length: 3

Mandatory? No

‘max-length’

Use this attribute to define the maximum length of values accepted for a parameter of type “string.”

Ensure the maximum length of the values are greater or equal to the length of the characters defined in min-length.

Example:

-
      name: appname
      type: string
      max-length: 64

Mandatory? No

‘min-items’

Use this attribute to define the minimum number of items in a parameter that is a list.

Ensure the minimum number of items are greater or equal to zero.

Example:

-
      name: server-ips
      type: ipaddress[]
      min-items: 2

Mandatory? No

‘max-items’

Use this attribute to define the maximum number of items in a parameter that is a list.

Ensure the maximum number of items are greater than the minimum number of items if defined.

Example:

-
      name: server-ips
      type: ipaddress[]
      min-items: 2
      max-items: 250

Mandatory? No

‘gui’

Use this attribute to customize the layout of the parameter in the ADM GUI.

Mandatory? No

‘columns’

This attribute is a subattribute of the gui attribute. Use this attribute to define the number of columns to display the type: object[] parameters in the ADM GUI.

Mandatory? No

‘updatable’

This attribute is a subattribute of the gui attribute. Use this attribute to specify whether the parameter can be updated after the configuration is created. Set this attribute only on simple parameter types such as string, boolean, or number.

If the value is set to false, the parameter field is grayed out when you update the configuration.

Mandatory? No

‘collapse_pane’

This attribute is a subattribute of the gui attribute. Use this attribute to specify whether the pane defining the layout of this object parameter is collapsible.

If the value is set to true, the user can expand or collapse the child parameters under this parent parameter.

Example:

gui:

 collapse_pane: true

 columns: 2

Example of a complete parameters section:


parameters:

   -

      name: name

      label: Name

      description: Name of the application

      type: string

      required: true

   -

      name: ip

      label: IP Address

      description: The virtual IP address used for this application

      type: ipaddress

      required: true

   -

      name: svc-servers

      label: Servers

      type: object\[\]

      required: true

      parameters:

        -

              name: svc-ip

              label: Server IP

              description: The IP address of the server

              type: ipaddress

              required: true

        -

              name: svc-port

              label: Server Port

              description: The TCP port of the server

              type: tcp-port

              default: 80

        -

              name: lb-alg

              label: LoadBalancing Algorithm

              type: string

              allowed-values:

                 - ROUNDROBIN

                 - LEASTCONNECTION

              default: ROUNDROBIN

        -

              name: enable-healthcheck

              label: Enable HealthCheck?

              type: boolean

              default: true

The following is an example that defines all the attributes of a list and the values explained in earlier sections:


        -
              name: features-list

              type: string[]

              min-length: 1

              max-length: 3

              min-items: 1

              max-items: 3

              pattern: "\[A-Z\]+"

              allowed-values:

                - SP

                - LB

                - CS

              default:

                - LB

‘layout’

This attribute is a subattribute of the gui attribute. Use this attribute to display the list values as radio buttons. Set the layout attribute to radio in the parameter section of a StyleBook definition. It applies to the parameter that has the allowed-values attribute. When you create a configuration pack, the ADM GUI displays the values in the allowed-values list as radio buttons.

Example:

-
    gui:
        layout: radio
    allowed-values:
        - One
        - Two
        - Three

The One, Two, and Three values appear as radio buttons in the ADM GUI.

‘dependent-parameters’

This attribute is a subattribute of the gui attribute. It dynamically controls the parameter’s appearance or its initial value in the StyleBook configuration form based on the value specified in another parameter.

Specify this attribute on a source parameter that controls the parameter’s behavior on the form. You can include multiple conditions that control other parameters. For example, a source parameter protocol can have a dependent-parameter certificate, which only appears if the protocol parameter value is SSL.

Each condition can have the following attributes:

  • target-parameter: Specify the target parameter to which this condition applies.

  • matching-values: Specify the list of values of the source parameter that trigger the action.

  • action: Specify one of the following actions on the targeted parameter:

    • read-only: The parameter is made read-only.

    • show: The parameter appears in the form if it is hidden.

    • hide: The parameter is removed from the form.

    • set-value: The parameter value is set to the value specified in the value attribute.

  • value: The value of the target parameter if the action is set-value.

When a user input matches the specified values on the source parameter, the target parameter’s appearance or value changes according to the specified action.

Example:

 -
    name: lb-virtual-port
    label: "Load Balanced App Virtual Port"
    description: "TCP port representing the Load Balanced application"
    type: tcp-port
    gui:
      updatable: false
      dependent-parameters:
            -
              matching-values:
                - 80
              target-parameter: $parameters.lb-service-type
              action: set-value
              allowed-values:
              - HTTP
              - TCP
              - UDP

    default: 80

In this example, the dependent parameter is specified under the lb-virtual-port parameter (source parameter).

When the source parameter value is set to 80, the lb-service-type parameter triggers the set-value action. As a result, a user is allowed to select one of the following options:

  • HTTP
  • TCP
  • UDP