You use allowlists to designate specific URLs that are pre-approved for access by your script or add-on. Allowlists help protect user data; when you define a allowlist, script projects can't access URLs that have not been allowlisted.
You use allowlists when your script or add-on performs the following actions:
- Retrieves or fetches information from an external location (such as HTTPS
endpoints) using the Apps Script
UrlFetchservice. To allowlist URLs for fetching, include the
urlFetchWhitelistfield in your manifest file.
- Opens or displays a URL in response to a user action (Required for
Google Workspace Add-ons that open or display URLs that are external to
Google). To allowlist URLs for opening, include the
addOns.common.openLinkUrlPrefixesfield in your manifest file.
Adding prefixes to your allowlist
When you specify allowlists in your manifest file (by including either the
urlFetchWhitelist field), you must
include a list of URL prefixes. The prefixes you add to the manifest must
satisfy the following requirements:
- Each prefix must be a valid URL.
- Each prefix must use
- Each prefix must have a full domain.
- Each prefix must have a non-empty path. For example,
https://www.google.com/is valid but
- You can use wildcards to match URL subdomain prefixes.
- A single
*wildcard can be used in the
addOns.common.openLinkUrlPrefixesfield to match all links, but this is not recommended as it can expose a user's data to risk and can prolong the add-on review process. Only use a wildcard if your add-on functionality requires it.
When determining if a URL matches a allowlisted prefix, the following rules apply:
- Path matching is case-sensitive.
- If the prefix is identical to the URL, it is a match.
- If the URL is the same or a child of the prefix, it is a match.
For example, the prefix
https://example.com/foo matches the following URLs:
You can use a single wildcard character (
*) to match a subdomain for both the
fields. You can't use more than one wildcard to match multiple subdomains, and
the wildcard must represent the leading prefix of the URL.
For example, the prefix
https://*.example.com/foo matches the following
https://*.example.com/foo doesn't match the following
https://example.com/foo(at least one subdomain must be present)
Some of the prefix rules are enforced when you try to save your manifest. For example, the following prefixes cause an error if they are present in your manifest when you attempt to save:
https://*.*.example.com/foo(multiple wildcards are forbidden)
https://subdomain.*.example.com/foo(wildcards must be used as a leading prefix)