Add support for arrays server default values (#921)

Author: delvedor

compiler/model/metamodel.ts

@@ -127,7 +127,7 @@ export class Property {
   docUrl?: string
   docId?: string
   since?: string
-  serverDefault?: boolean | string | number
+  serverDefault?: boolean | string | number | string[] | number[]
   deprecation?: Deprecation
   /**
    * If specified takes precedence over `name` when generating code. `name` is always the value

compiler/model/utils.ts

@@ -684,7 +684,7 @@ function hoistPropertyAnnotations (property: model.Property, jsDocs: JSDoc[]): v
       assert(jsDocs, value.trim() !== '', `Property ${property.name}'s @doc_id is cannot be empty`)
       property.docId = value
     } else if (tag === 'server_default') {
-      assert(jsDocs, property.type.kind === 'instance_of' || property.type.kind === 'union_of', `Default values can only be configured for instance_of or union_of types, you are using ${property.type.kind}`)
+      assert(jsDocs, property.type.kind === 'instance_of' || property.type.kind === 'union_of' || property.type.kind === 'array_of', `Default values can only be configured for instance_of or union_of types, you are using ${property.type.kind}`)
       assert(jsDocs, !property.required, 'Default values can only be specified on optional properties')
       if (property.type.kind === 'union_of') {
         let valueType = ''
@@ -704,6 +704,14 @@ function hoistPropertyAnnotations (property: model.Property, jsDocs: JSDoc[]): v
         })
         assert(jsDocs, unionTypes.includes(valueType), `The configured server_default value is not present in the union value: ${unionTypes.join(' | ')}`)
         property.serverDefault = value
+      } else if (property.type.kind === 'array_of') {
+        try {
+          value = eval(value) // eslint-disable-line
+        } catch (err) {
+          assert(jsDocs, false, 'The default value is not formatted properly')
+        }
+        assert(jsDocs, Array.isArray(value), 'The default value should be an array')
+        property.serverDefault = value
       } else {
         switch (property.type.type.name) {
           case 'boolean':

docs/modeling-guide.md

@@ -431,6 +431,17 @@ class Foo {
 }
 ```
 
+If you need to specify a server default value for an array, you must use the JavaScript array syntax:
+
+```ts
+class Foo {
+  bar: string
+  /** @server_default ['hello'] */
+  baz?: string[]
+  faz: string
+}
+```
+
 #### `@doc_url`
 
 The documentation url for the parameter.

output/schema/schema.json

@@ -25,6 +25,7 @@ import { FilterRef } from './Filter'
 export class DetectionRule {
   /**
    * The set of actions to be triggered when the rule applies. If more than one action is specified the effects of all actions are combined.
+   * @server_default ['skip_result']
    */
   actions?: RuleAction[]
   /**