What you need to know when invalidating files - Amazon CloudFront
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What you need to know when invalidating files

When you specify a file to invalidate, refer to the following information:

Case sensitivity

Invalidation paths are case sensitive. For example, /images/image.jpg and /images/Image.jpg specify two different files.

Changing the URI by using a Lambda function

If your CloudFront distribution triggers a Lambda function on viewer request events, and if the function changes the URI of the requested file, we recommend that you invalidate both URIs to remove the file from CloudFront edge caches:

  • The URI in the viewer request

  • The URI after the function changed it

Example

Suppose your Lambda function changes the URI for a file from:

https://d111111abcdef8.cloudfront.net/index.html

To a URI that includes a language directory:

https://d111111abcdef8.cloudfront.net/en/index.html

To invalidate the file, you must specify the following paths:

  • /index.html

  • /en/index.html

For more information, see Invalidation paths.

Default root object

To invalidate the default root object (file), specify the path the same way that you specify the path for any other file. For more information, see How default root object works.

Forwarding cookies

If you configured CloudFront to forward cookies to your origin, CloudFront edge caches might contain several versions of the file. When you invalidate a file, CloudFront invalidates every cached version of the file regardless of its associated cookies. You can’t selectively invalidate some versions and not others based on the associated cookies. For more information, see Cache content based on cookies.

Forwarding headers

If you configured CloudFront to forward a list of headers to your origin and to cache based on the values of the headers, CloudFront edge caches might contain several versions of the file. When you invalidate a file, CloudFront invalidates every cached version of the file regardless of the header values. You can’t selectively invalidate some versions and not others based on header values. (If you configure CloudFront to forward all headers to your origin, CloudFront doesn't cache your files.) For more information, see Cache content based on request headers.

Forwarding query strings

If you configured CloudFront to forward query strings to your origin, you must include the query strings when invalidating files, as shown in the following examples:

  • /images/image.jpg?parameter1=a

  • /images/image.jpg?parameter1=b

If client requests include five different query strings for the same file, you can either invalidate the file five times, once for each query string, or you can use the * wildcard in the invalidation path, as shown in the following example:

/images/image.jpg*

For more information about using wildcards in the invalidation path, see Invalidation paths.

For more information about query strings, see Cache content based on query string parameters.

To determine which query strings are in use, you can enable CloudFront logging. For more information, see Configure and use standard logs (access logs).

Maximum allowed

For more information about the maximum number of invalidations allowed, see Concurrent invalidation request maximum.

Microsoft Smooth Streaming files

You can't invalidate media files in the Microsoft Smooth Streaming format when you have enabled Smooth Streaming for the corresponding cache behavior.

Non-ASCII or unsafe characters in the path

If the path includes non-ASCII characters or unsafe characters as defined in RFC 1738, URL-encode those characters. Don't URL-encode any other characters in the path, or CloudFront won't invalidate the old version of the updated file.

Invalidation paths

The path is relative to the distribution. For example, to invalidate the file at https://d111111abcdef8.cloudfront.net/images/image2.jpg, you would specify /images/image2.jpg.

Note

In the CloudFront console, you can omit the leading slash in the path, like this: images/image2.jpg. When you use the CloudFront API directly, invalidation paths must begin with a leading slash.

You can also invalidate multiple files simultaneously by using the * wildcard. The *, which replaces 0 or more characters, must be the last character in the invalidation path.

If you use the Amazon Command Line Interface (Amazon CLI) to invalidate files and you specify a path that includes the * wildcard, you must use quotes (") around the path like "/*".

Example: Invalidation paths

  • To invalidate all files in a directory:

    /directory-path/*

  • To invalidate a directory, all of its subdirectories, and all files in the directory and subdirectories:

    /directory-path*

  • To invalidate all files that have the same name but different file name extensions, such as logo.jpg, logo.png, and logo.gif:

    /directory-path/file-name.*

  • To invalidate all of the files in a directory for which the file name starts with the same characters (such as all of the files for a video in HLS format), regardless of the file name extension:

    /directory-path/initial-characters-in-file-name*

  • When you configure CloudFront to cache based on query string parameters and you want to invalidate every version of a file:

    /directory-path/file-name.file-name-extension*

  • To invalidate all files in a distribution:

    /*

The maximum length of a path is 4,000 characters. You can’t use a wildcard within the path. It can only be added at the end of the path.

For information about invalidating files if you use a Lambda function to change the URI, see Changing the URI Using a Lambda Function.

If the invalidation path is a directory and if you have not standardized on a method for specifying directories—with or without a trailing slash (/)—we recommend that you invalidate the directory both with and without a trailing slash, for example, /images and /images/.

Signed URLs

If you are using signed URLs, invalidate a file by including only the portion of the URL before the question mark (?).