Template functions
StackState SaaS
StackState Template JSON (STJ) incorporates several custom handlebars functions that can be used, for example, to get existing nodes from the graph, create new nodes or join texts together. The available StackState functions are described below.
Adds number variables together.
Two or more number variables.
Template
Data
Result
{{# add a b c }}
[ a: 1, b: 2, c: 3 ]
6
The
concat function concatenates two values:concat "Type=ComponentType;Name=" element.type.name
The
get function finds a node of a certain type by its unique identifier without needing to specify the type of the node. The function finds a node in a nested way, first finding the identifier and then finding the type and name in the scope of the first resolved node.get <identifier> Type=<type>;Name=<name>
- Resolve the
ProductionEnvironmentusing:get "urn:stackpack:aws:environment:production" - Resolve the
Parametersmetricsfrom the CheckFunction identified byurn:stackpack:aws:check_function:basicusing:get "urn:stackpack:aws:check_function:basic" "Type=Parameter;Name=metrics"
Gets the first node from a list of node identifiers (URNs).
Two or more URNs strings.
Template
Data
Result
{{ getFirstExisting "urn:stackpack:aws:domain:Old" "urn:stackpack:aws:domain:New" }}
This example assumes
urn:stackpack:aws:Old: does not exist, whereas urn:stackpack:aws:domain:New does exist.urn:stackpack:aws:domain:New
The
getOrCreate function first tries to resolve a node by its identifier and then by the fallback create-identifier. If none are found, the function will create a node using the specified Type and Name arguments and the newly created node will be identified with the create-identifier value.getOrCreate <identifier> <create-identifier> Type=<type>;Name=<name>
Note that:
getOrCreateworks only with the following (simple) types: Environment, Layer, Domain, ComponentType and RelationType.create-identifiermust be a value in the"urn:system:auto"namespace.
We strongly encourage to use
get and getOrCreate as resolving nodes by identifier is safer than by name due to the unique constraint enforced in the identifier values.Find the
Production Environment by its identifier and fallback identifier, or otherwise create it:getOrCreate "urn:stackpack:aws:environment:production" "urn:system:auto:stackpack:aws:environment:production" "Type=Environment;Name=Production"
The
identifier function creates an identifier out of an identifier prefix, a component type and a component name.identifier "urn:stackpack:common" "ComponentType" element.type.name
This function will only work when the template is loaded from a StackPack.
Includes the content of another file inside this template. This can come in handy when template files become exceedingly large, when working with images or when you want to reuse the same template fragments in multiple locations.
include "<filename>" "<encoding>"
- filename - The name of the file to include from the StackPack. The file must exist in the
provisioningdirectory or one of its subdirectories. - encoding (optional, default =
handlebars) - Choice of:handlebars- Included file will be interpreted as StackState Templated JSON.identity- Included file will be not be interpreted, but simply will be included as text.base64- Included file will be loaded using a BASE64 encoding. This is possible for the image types:png,jpg,gifandsvg.
- Include a script:
Template
Data
Result
{
"_type": "CheckFunction",
"description": "Converts AWS state to StackState run state",
"identifier": "urn:stackpack:aws:shared:check-function:aws-event-run-state",
"name": "AWS event run state",
"parameters": [
{
"_type": "Parameter",
"multiple": false,
"name": "events",
"required": true,
"system": false,
"type": "EVENT_STREAM"
}
],
"returnTypes": [ "RUN_STATE" ],
"script": "{{ include "./scripts/AWS event run state.groovy" }}"
}
The file
/provisioning/script/AWS event run state.groovy in the AWS StackPack contains return RUNNING{
"_type": "CheckFunction",
"description": "Converts AWS state to StackState run state",
"identifier": "urn:stackpack:aws:shared:check-function:aws-event-run-state",
"name": "AWS event run state",
"parameters": [
{
"_type": "Parameter",
"multiple": false,
"name": "events",
"required": true,
"system": false,
"type": "EVENT_STREAM"
}
],
"returnTypes": [ "RUN_STATE" ],
"script": "return RUNNING"
}
- Include an image:
Template
Data
Result
{
"_type": "ComponentType",
"identifier": "urn:stackpack:aws:shared:component-type:aws.cloudformation",
"name": "aws.cloudformation",
"iconbase64": "{{ include "./icons/aws.cloudformation.png" "base64" }}"
}
The file
/provisioning/icons/aws.cloudformation.png contains an image of the AWS CloudFormation logo.{
"_type": "ComponentType",
"identifier": "urn:stackpack:aws:shared:component-type:aws.cloudformation",
"name": "aws.cloudformation",
"iconbase64": "data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAQAAAAEACAYAfkYAhBBGAIQQCgAhhAJACKEAEEIoAIQQCgAhhAJACKEAEEIoAIQQCgAhhAJACKEAEEIoAIQQCgAhhAJACKEAEEL65P8BEaL9HlGPnesAAAAASUVORK5CYII"
}
Joins array or map data as a text usign a separator, prefix and suffix. This is especially handy when producing JSON arrays.
# join <iteratee> "<separator>" "<prefix>" "<suffix>"
- 1.iteratee - the element to repeat and join together.
- 2.separator - the text that is used to separate the elements.
- 3.prefix (optional) - text that is placed at the beginning of the joined text.
- 4.suffix (optional) - text is appended at the end of the joined text.
- Join an array of labels to create a JSON array of objects:
Template
Data
Result
{{# join labels "," "[" "]" }}
{
"_type": "Label",
"name": "{{this}}"
}
{{/ join }}
[ labels: [
"hello",
"world"
] ]
[{
"_type": "Label",
"name": "hello"
},{
"_type": "Label",
"name": "world"
}]
- Join a map of labels to create a JSON array of objects:
Template
Data
Result
{{# join labels "," "[" "]" }}
{
"_type": "Label",
"name": "{{key}}:{{this}}"
}
{{/ join }}
[ labels: [
"key1": "hello",
"key2": "world"
] ]
[{
"_type": "Label",
"name": "key1:hello"
},{
"_type": "Label",
"name": "key2:world"
}]
Last modified 7mo ago