Display templates is an important part of controlling how the events are rendered in the browser, exports or over any other stream. Display Templates cause an additional field to be returned on event objects from the Audit Log APIs.
A display template has the following components:
Definitions
Name
The name is internal only to the admin site. This is a place for you to record what the template is attempting to do.
Rules
The rules field is a collection of rules that will be evaluated by the Replicated Audit Log rules engine to determine if this template shoud be applied to the event. We’ll cover that in detail shortly. But the idea is that you can have multiple rules, and the first one that matches will control how the event is rendered.
Template
A handlebars-enabled, markdown rendered display template to use when the rules evaluate to true for a particular event. This ultimately is the text that you want to show for the matching events.
Rules
Rules are processed against the event object. The best example is with actual data: you can click the Raw object in the admin site and see any actual event object. This is the exact context that is sent into the rule engine.
Rules are expressed as an array of comparators. When the value of the path matches the comparator, the rule evaluates to true and the template is applied. The Audit Log supports a large number of comparators, a full list of comparators is available.
Examples
This rule matches when the action is set to the string “document.edit”:
[
{
"comparator": "is",
"path": "action",
"value": "document.edit"
}
]
This rule matches when the action is set to the string “document.edit” AND the type of the document is set to “spreadsheet”:
[
{
"comparator": "is",
"path": "action",
"value": "document.edit"
},
{
"comparator": "is",
"path": "target.type",
"value": "spreadsheet"
}
]
Templates
Templates are a handlebars string that will be used to display the event. The context of the handlebars engine is the event object, and the output is a markdown string.
Examples
Partial Event:
{
"action": "document.create",
"actor": {
"name": "Dr. Evil",
},
"target": {
"type": "spreadsheet",
"name": "Master Plan For World Domination.xlsx"
}
}
Template:
{{ actor.name }} created the document {{ target.name }}
Result: Dr. Evil created the document Master Plan For World Domination
Template Comparators
Deep dive on the Display Template JSON DSL
The following values are acceptable for “comparator” field in rules in the Replicated Audit Log rules engine:
| Comparator | Desscription |
|---|---|
eq |
Matches when the value is equal to the event object data at path. This compares values only and doesn’t compare types. |
is |
The same as eq but it also compares types of objects. |
neq |
Matches when the value is not equal to the event object data at path. This compares values only and doesn’t compare types. This is the inverse of eq. |
not |
The same as neq but it also compares types of objects. This is the inverse of is. |
lt |
Matches when the value is less than the event object data at path. |
lte |
Matches when the value is less than or equal to the event object data at path. |
gt |
Matches when the value is greater than the event object data at path. |
gte |
Matches when the value is greater than or equal to the event object data at path. |
exists |
Matches when the value key exists and is not null on the event object data. |
nexists |
Matches when the value key does not exists or is null on the event object data. |
contains |
Matches when the event object data at path contains value. |
ncontains |
Matches when the event object data at path does not contain value. |
matches |
This rule is a raw regex rule. When the value is interpreted as a regular expression and applied to the event object data at path, returns the regex match value. |