Filtering the Data Transferred by AWS DataSync

When you transfer data from your source to your destination location, you can apply filters to transfer only a subset of the files in your source location. For example, if your source location includes temporary files that end with .tmp, you can create an exclude filter that ensures that these files are not transferred to the destination.

Filtering is an optional configuration to specify if you want to transfer a subset of your source files. You can leave the filter configuration empty if you want all files from the source to be transferred to the destination location.

Filtering Terms, Definitions, and Syntax

Following are some terms and definitions for use with filtering:

Filter

The whole string that makes up a particular filter, for example: *.tmp|*.temp

Filters are made up of patterns that are delimited with a | (pipe). A delimiter is not needed when you add patterns on the console because each pattern is added separately.

Pattern

A pattern within a filter. For example, *.tmp is a pattern that is part of the *.tmp|*.temp filter.

Folders

• All filters are relative to the source location path. For example, suppose that you specify /my_source/ as the source path when you create the task and create the include filter /transfer_this/. In this case, only the directory /my_source/transfer_this/ and its content are transferred.

• To specify a folder directly under the source location, include a backslash (/) in front of the folder name. In the example preceding, the pattern uses /transfer_this, not transfer_this.

• The following patterns are interpreted the same way and match both the folder and its content.

  /dir

  /dir/

• When you are transferring data from or to an Amazon S3 bucket, DataSync treats the / character in the object key as the equivalent of a folder on a file system.

Special Characters

Following are special characters for use with filtering.

Special Character	Description
* (wildcard)	A character used to match zero or more characters. For example, /movies_folder* matches both /movies_folder and /movies_folder1.
| (pipe delimiter)	A character used as a delimiter between patterns. It enables specifying multiple patterns, any of which can match the filter. For example, *.tmp|*.temp matches files ending with either tmp or temp. Note This delimiter is not needed when you add patterns on the console because each pattern is added on a separate line.
\ (backslash)	This character is used for escaping when a file or object names contains special characters (*, |, \). A double backslash (\\) is required when a backslash is part of a file name. Similarly, \\\\ represents two consecutive backslashes in a file name. A backslash followed by a pipe (\|) is required when a pipe is part of a file name. \ followed by any other character, or at the end of a pattern, is ignored.

Excluding Data from a Transfer

Exclude filters define files, folders, and objects that are excluded when you transfer files from a source to a destination location. You can configure these filters when you create or edit a task.

To create a task with an exclude filter in the DataSync console, specify a list of patterns in the Filtering configuration – (optional) section in the Exclude patterns box. For example, to exclude temporary folders, you can specify */temp in the exclude patterns text box, choose Add patterns and then specify */tmp in the second text box. To add more patterns to the filter, choose Add pattern. When you are using the CLI, note that quotes are required around the filter and a | (pipe) is used as a delimiter. For this example, you would specify '*/temp|*/tmp'.

The following screenshot shows the Edit Task wizard with patterns that exclude temporary folders.

After you have created a task, you can edit the task configuration to add or remove patterns from the filter.

You can also use the AWS Command Line Interface (AWS CLI) to create an exclude filter. The following example shows such a CLI command.

aws datasync create-task 
    --source-location-arn 'arn:aws:datasync:region:account-id:location/location-id'
    --destination-location-arn 'arn:aws:datasync:region:account-id:location/location-id'
    --cloud-watch-log-group-arn 'arn:aws:logs:region:account-id:log-group:your-log-group' 
    --name your-task-name
    --excludes FilterType=SIMPLE_PATTERN,Value='*/temp|*/tmp'

Note

If you are migrating files from NetApp, we recommend that you exclude NetApp backup folders by specifying */.snapshot as a pattern in your filter.

Including Data in a Transfer

Include filters define files, folders, and objects that are transferred when you run a task. You configure these filters as part of the configuration when you start a task.

To start a task with an include filter, specify a list of patterns to be included in the optional configuration when you start a task. To do this, use the Start with Overrides option in the DataSync console.

Files and folders matching the include filters are the only ones that are transferred. For example, to include only a subset of your source folders, you might specify /important_folder_1|/important_folder_2.

You can also use the AWS CLI to create an include filter. The following example shows the CLI command. Take note of the quotes around the filter and the | (pipe) that is used as a delimiter.

aws datasync start-task-execution 
   --task-arn 'arn:aws:datasync:region:account-id:task/task-id' 
   --includes FilterType=SIMPLE_PATTERN,Value='/important_folder1|/important_folder2'

Note

Currently, include filters support the * character only as the rightmost character in a pattern. For example, /documents*|/code* is supported but *.txt is not supported.

Sample Filters for Common Uses

In this section, you can find common uses for filtering and sample filters for them.

Exclude some folders from your source location

In some cases, you might need to exclude folders in your source location to keep them from being copied to your destination. For example, you might have temporary work-in-progress folders. Or you might use NetApp and want to exclude NetApp backup folders. In these cases, you use the following filter.

*/.snapshot

To exclude folders at any level in the file hierarchy, you can create a task to configure an exclude filter like the following.

*/folder-to-exclude-1|*/folder-to-exclude-2

To exclude folders at the top level of the source location, you can create a task to configure an exclude filter like the following.

/top-level-folder-to-exclude-1|/top-level-folder-to-exclude-2

Include only a subset of the folders on your source location

In some cases, your source location might be a large share, and you need to transfer only a subset of the folders under the root. To include specific folders, start a task execution with an include filter like the following.

/folder-to-transfer

Exclude specific file types

To exclude certain file types from the transfer, you can create a task execution with an exclude filter such as *.temp.

Transfer only individual files you specify

To transfer a list of individual files, start a task execution with an include filter like the following: “/folder/subfolder/file1.txt|/folder/subfolder/file2.txt|/folder/subfolder/file2.txt”

Note

The string length is limited to 100,000 characters.