有別於 local
和 sync
儲存空間區域,managed
儲存空間區域的結構必須
宣告為 JSON 結構定義,且經過 Chrome 嚴格驗證。這個結構定義必須儲存在
檔案 (由 "storage"
資訊清單鍵的 "managed_schema"
屬性表示),並宣告
應用程式支援的企業政策。
政策類似選項,但是由系統管理員 (而非使用者) 設定 允許為機構中的所有使用者預先設定應用程式。瞭解 Chrome 如何處理 政策。
宣告政策後,即可從 storage.managed API 讀取政策。完全由應用程式提供 強制執行管理員設定的政策
manifest.json 範例
storage.managed_schema
屬性代表應用程式中含有政策的檔案
結構定義。
{
"name": "My enterprise app",
"storage": {
"managed_schema": "schema.json"
},
...
}
Chrome 接著會從基礎作業系統和 Google Apps 載入這些政策 。偵測到政策變更時,就會觸發 storage.onChanged 事件。 包括如果應用程式使用事件頁面,瀏覽器並未執行時也包含在內。您可以驗證 Chrome 在 chrome://policy 載入的政策
結構定義格式
JSON 結構定義格式還有 Chrome 額外規定:
- 頂層結構定義必須採用
object
類型。 - 頂層
object
不得包含additionalProperties
。宣告的properties
是 政策。 - 每個結構定義都必須有一個
$ref
值或僅有一個type
。
如果結構定義無效,Chrome 就不會載入擴充功能,且會說明
未驗證結構定義如果政策值不符合結構定義,就不會
storage.managed
API 所發布。
結構定義範例
{
"type": "object",
// "properties" maps an optional key of this object to its schema. At the
// top-level object, these keys are the policy names supported.
"properties": {
// The policy name "AutoSave" is mapped to its schema, which in this case
// declares it as a simple boolean value.
// "title" and "description" are optional and are used to show a
// user-friendly name and documentation to the administrator.
"AutoSave": {
"title": "Automatically save changes.",
"description": "If set to true then changes will be automatically saved.",
"type": "boolean"
},
// Other simple types supported include "integer", "string" and "number".
"PollRefreshRate": {
"type": "integer"
},
"DefaultServiceUrl": {
"type": "string"
},
// "array" is a list of items that conform to another schema, described
// in "items". An example to this schema is [ "one", "two" ].
"ServiceUrls": {
"type": "array",
"items": {
"type": "string"
}
},
// A more complex example that describes a list of bookmarks. Each bookmark
// has a "title", and can have a "url" or a list of "children" bookmarks.
// The "id" attribute is used to name a schema, and other schemas can reuse
// it using the "$ref" attribute.
"Bookmarks": {
"type": "array",
"id": "ListOfBookmarks",
"items": {
"type": "object",
"properties": {
"title": { "type": "string" },
"url": { "type": "string" },
"children": { "$ref": "ListOfBookmarks" }
}
}
},
// An "object" can have known properties listed as "properties", and can
// optionally have "additionalProperties" indicating a schema to apply to
// keys that aren't found in "properties".
// This example policy could map a URL to its settings. An example value:
// {
// "youtube.com": {
// "blocklisted": true
// },
// "google.com": {
// "bypass_proxy": true
// }
// }
"SettingsForUrls": {
"type": "object",
"additionalProperties": {
"type": "object",
"properties": {
"blocklisted": { "type": "boolean" },
"bypass_proxy": { "type": "boolean" }
}
}
}
}
}