Dynamic Attribute Function Reference

Extensions to the Go language templating language.

All functions specified by the Go language template specification are supported by the Service Broker. The service broker also defines some application specific functions as documented below.

Arguments described as optional may be specified as nil.

`registry`

The registry function performs a lookup of a value from the registry. This function will raise an error if the registry is corrupt or an attempt is made to read a protected key.

{{ registry "key" }}

Arguments

key: The key argument is required and must be a string.

Result

The result type varies based upon the type of the registry value. If the registry key does not exist, the result will be nil.

`parameter`

The parameter function looks up a user specified parameter provided with an Open Service Broker API request.

{{ parameter "/path" }}

Arguments

path: The path argument is a JSON pointer identifying a value within a JSON object. The path argument is required and must be a string.

Result

The result type varies based upon the type of the parameter value. If the pointer references a path that does not exist, the result will be nil

`snippet`

The snippet function looks up and renders a configuration template snippet. This function will raise an error if the snippet does not exist or any error occurs while rendering the snippet.

{{ snippet "template" }}

Arguments

name: The name argument is required and must be a string.

Result

The result type will be an object.

`list`

The list function accepts a variable number of arguments and converts them into a list/array.

{{ list "item" "item" }}

Arguments

item: The item argument is optional and may be any type. The item argument may be specified any number of times.

Result

The result type will be an array.

`default`

The default function provides a default value if the input is nil.

{{ parameter "/path" | default "value" }}

Arguments

default: The default argument is required and may be any type.
value: The value argument is required and may be any type.

Result

The result type will be any type.

`json`

The json function serializes its input as a JSON string. All action pipelines that generate output are implicitly appended with the JSON function.

{{ "value" | json }}

Arguments

value: The value argument is required and may be any type.

Result

The result will be a string.

`required`

The required function raises an error when its input is nil.

{{ parameter "/path" | required }}

Arguments

value: The value argument is required and may be any type.

Result

The result type will be any type.

`generatePassword`

The generatePassword function generates a cryptographically secure random password.

{{ generatePassword 32 "12345abcde" }}

Arguments

length: The length argument is required and must be an integer.
dictionary: The dictionary argument is optional and must be a string. This argument defaults to abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789.

Result

The result type will be a string.

`generatePrivateKey`

The generatePrivateKey function generates a PEM encoded, cryptographic private key. RSA, ECDSA and ED25519 are all fully supported. Password protected private keys are not currently supported.

{{ generatePrivateKey "RSA" "PKCS#8" 2048 }}

Arguments

type: This argument is required and must be one of RSA, EllipticP224, EllipticP256, EllipticP384, EllipticP521 or ED25519.
encoding: This argument is required and must be one of PKCS1, PKCS8 or SEC1. PKCS#1 can only be used with RSA private keys. PKCS#8 can be used with any private key type. SEC 1 can only be used with elliptic private keys.
bits: This argument is optional and must be an integer. It is required for RSA private keys and ignored for all other private key types

Result

The result will be a string.

`generateCertificate`

The generateCertificate function generates an X.509 certificate from a PEM encoded private key. Only RSA and ECDSA private keys are supported. Certificates specified without a CA will be self-signed, rather than signed by the CA.

{{ generateCertificate (registry "key.pem") "My CA" "720h" "CA" nil nil nil }}

Arguments

key: This argument is required and must be a string.
cn: This argument is required and must be a string.
lifetime: This argument is required and must be a string. The format of lifetime is defined by the golang duration specification.
usage: This argument is required and must be one of CA, Server or Client.
sans: This argument is optional and must be an array of strings. Subject alternative names are defined as type:name where type is one of DNS or EMAIL. The name is a valid DNS name or E-mail address respectively.
cakey: This argument is optional and must be a string.
cacert: This argument is optional and must be a string.

Result

The result will be a string.