Copy data from or to Azure File Storage by using Azure Data Factory

APPLIES TO: yesAzure Data Factory yesAzure Synapse Analytics (Preview)

This article outlines how to copy data to and from Azure File Storage. To learn about Azure Data Factory, read the introductory article.

Supported capabilities

This Azure File Storage connector is supported for the following activities:

Specifically, this Azure File Storage connector supports copying files as-is or parsing/generating files with the supported file formats and compression codecs.

Getting started

To perform the Copy activity with a pipeline, you can use one of the following tools or SDKs:

The following sections provide details about properties that are used to define Data Factory entities specific to Azure File Storage.

Linked service properties

The following properties are supported for Azure File Storage linked service:

Property Description Required
type The type property must be set to: AzureFileStorage. Yes
host Specifies the Azure File Storage endpoint as:
-Using UI: specify \\<storage name>.file.core.windows.net\<file service name>
- Using JSON: "host": "\\\\<storage name>.file.core.windows.net\\<file service name>".
Yes
userid Specify the user to access the Azure File Storage as:
-Using UI: specify AZURE\<storage name>
-Using JSON: "userid": "AZURE\\<storage name>".
Yes
password Specify the storage access key. Mark this field as a SecureString to store it securely in Data Factory, or reference a secret stored in Azure Key Vault. Yes
connectVia The Integration Runtime to be used to connect to the data store. You can use Azure Integration Runtime or Self-hosted Integration Runtime (if your data store is located in private network). If not specified, it uses the default Azure Integration Runtime. No for source, Yes for sink

Important

  • To copy data into Azure File Storage using Azure Integration Runtime, explicitly create an Azure IR with the location of your File Storage, and associate in the linked service as the following example.
  • To copy data from/to Azure File Storage using Self-hosted Integration Runtime outside of Azure, remember to open outbound TCP port 445 in your local network.

Tip

When using ADF UI for authoring, you can find the specific entry of "Azure File Storage" for linked service creation, which underneath generates type FileServer object.

Example:

{
    "name": "AzureFileStorageLinkedService",
    "properties": {
        "type": "AzureFileStorage",
        "typeProperties": {
            "host": "\\\\<storage name>.file.core.windows.net\\<file service name>",
            "userid": "AZURE\\<storage name>",
            "password": {
                "type": "SecureString",
                "value": "<storage access key>"
            }
        },
        "connectVia": {
            "referenceName": "<name of Integration Runtime>",
            "type": "IntegrationRuntimeReference"
        }
    }
}

Dataset properties

For a full list of sections and properties available for defining datasets, see the Datasets article.

Azure Data Factory supports the following file formats. Refer to each article for format-based settings.

The following properties are supported for Azure File Storage under location settings in format-based dataset:

Property Description Required
type The type property under location in dataset must be set to FileServerLocation. Yes
folderPath The path to folder. If you want to use wildcard to filter folder, skip this setting and specify in activity source settings. No
fileName The file name under the given folderPath. If you want to use wildcard to filter files, skip this setting and specify in activity source settings. No

Example:

{
    "name": "DelimitedTextDataset",
    "properties": {
        "type": "DelimitedText",
        "linkedServiceName": {
            "referenceName": "<Azure File Storage linked service name>",
            "type": "LinkedServiceReference"
        },
        "schema": [ < physical schema, optional, auto retrieved during authoring > ],
        "typeProperties": {
            "location": {
                "type": "FileServerLocation",
                "folderPath": "root/folder/subfolder"
            },
            "columnDelimiter": ",",
            "quoteChar": "\"",
            "firstRowAsHeader": true,
            "compressionCodec": "gzip"
        }
    }
}

Copy activity properties

For a full list of sections and properties available for defining activities, see the Pipelines article. This section provides a list of properties supported by Azure File Storage source and sink.

Azure File Storage as source

Azure Data Factory supports the following file formats. Refer to each article for format-based settings.

The following properties are supported for Azure File Storage under storeSettings settings in format-based copy source:

Property Description Required
type The type property under storeSettings must be set to FileServerReadSettings. Yes
Locate the files to copy:
OPTION 1: static path
Copy from the given folder/file path specified in the dataset. If you want to copy all files from a folder, additionally specify wildcardFileName as *.
OPTION 2: wildcard
- wildcardFolderPath
The folder path with wildcard characters to filter source folders.
Allowed wildcards are: * (matches zero or more characters) and ? (matches zero or single character); use ^ to escape if your actual folder name has wildcard or this escape char inside.
See more examples in Folder and file filter examples.
No
OPTION 2: wildcard
- wildcardFileName
The file name with wildcard characters under the given folderPath/wildcardFolderPath to filter source files.
Allowed wildcards are: * (matches zero or more characters) and ? (matches zero or single character); use ^ to escape if your actual folder name has wildcard or this escape char inside. See more examples in Folder and file filter examples.
Yes
OPTION 3: a list of files
- fileListPath
Indicates to copy a given file set. Point to a text file that includes a list of files you want to copy, one file per line which is the relative path to the path configured in the dataset.
When using this option, do not specify file name in dataset. See more examples in File list examples.
No
Additional settings:
recursive Indicates whether the data is read recursively from the subfolders or only from the specified folder. Note that when recursive is set to true and the sink is a file-based store, an empty folder or subfolder isn't copied or created at the sink.
Allowed values are true (default) and false.
This property doesn't apply when you configure fileListPath.
No
deleteFilesAfterCompletion Indicates whether the binary files will be deleted from source store after successfully moving to the destination store. The file deletion is per file, so when copy activity fails, you will see some files have already been copied to the destination and deleted from source, while others are still remaining on source store.
This property is only valid in binary copy scenario, where data source stores are Blob, ADLS Gen1, ADLS Gen2, S3, Google Cloud Storage, File, Azure File, SFTP, or FTP. The default value: false.
No
modifiedDatetimeStart Files filter based on the attribute: Last Modified.
The files will be selected if their last modified time is within the time range between modifiedDatetimeStart and modifiedDatetimeEnd. The time is applied to UTC time zone in the format of "2018-12-01T05:00:00Z".
The properties can be NULL, which means no file attribute filter will be applied to the dataset. When modifiedDatetimeStart has datetime value but modifiedDatetimeEnd is NULL, it means the files whose last modified attribute is greater than or equal with the datetime value will be selected. When modifiedDatetimeEnd has datetime value but modifiedDatetimeStart is NULL, it means the files whose last modified attribute is less than the datetime value will be selected.
This property doesn't apply when you configure fileListPath.
No
modifiedDatetimeEnd Same as above. No
maxConcurrentConnections The number of the connections to connect to storage store concurrently. Specify only when you want to limit the concurrent connection to the data store. No

Example:

"activities":[
    {
        "name": "CopyFromAzureFileStorage",
        "type": "Copy",
        "inputs": [
            {
                "referenceName": "<Delimited text input dataset name>",
                "type": "DatasetReference"
            }
        ],
        "outputs": [
            {
                "referenceName": "<output dataset name>",
                "type": "DatasetReference"
            }
        ],
        "typeProperties": {
            "source": {
                "type": "DelimitedTextSource",
                "formatSettings":{
                    "type": "DelimitedTextReadSettings",
                    "skipLineCount": 10
                },
                "storeSettings":{
                    "type": "FileServerReadSettings",
                    "recursive": true,
                    "wildcardFolderPath": "myfolder*A",
                    "wildcardFileName": "*.csv"
                }
            },
            "sink": {
                "type": "<sink type>"
            }
        }
    }
]

Azure File Storage as sink

Azure Data Factory supports the following file formats. Refer to each article for format-based settings.

The following properties are supported for Azure File Storage under storeSettings settings in format-based copy sink:

Property Description Required
type The type property under storeSettings must be set to FileServerWriteSettings. Yes
copyBehavior Defines the copy behavior when the source is files from a file-based data store.

Allowed values are:
- PreserveHierarchy (default): Preserves the file hierarchy in the target folder. The relative path of source file to source folder is identical to the relative path of target file to target folder.
- FlattenHierarchy: All files from the source folder are in the first level of the target folder. The target files have autogenerated names.
- MergeFiles: Merges all files from the source folder to one file. If the file name is specified, the merged file name is the specified name. Otherwise, it's an autogenerated file name.
No
maxConcurrentConnections The number of the connections to connect to the data store concurrently. Specify only when you want to limit the concurrent connection to the data store. No

Example:

"activities":[
    {
        "name": "CopyToAzureFileStorage",
        "type": "Copy",
        "inputs": [
            {
                "referenceName": "<input dataset name>",
                "type": "DatasetReference"
            }
        ],
        "outputs": [
            {
                "referenceName": "<Parquet output dataset name>",
                "type": "DatasetReference"
            }
        ],
        "typeProperties": {
            "source": {
                "type": "<source type>"
            },
            "sink": {
                "type": "ParquetSink",
                "storeSettings":{
                    "type": "FileServerWriteSettings",
                    "copyBehavior": "PreserveHierarchy"
                }
            }
        }
    }
]

Folder and file filter examples

This section describes the resulting behavior of the folder path and file name with wildcard filters.

folderPath fileName recursive Source folder structure and filter result (files in bold are retrieved)
Folder* (empty, use default) false FolderA
    File1.csv
    File2.json
    Subfolder1
        File3.csv
        File4.json
        File5.csv
AnotherFolderB
    File6.csv
Folder* (empty, use default) true FolderA
    File1.csv
    File2.json
    Subfolder1
        File3.csv
        File4.json
        File5.csv
AnotherFolderB
    File6.csv
Folder* *.csv false FolderA
    File1.csv
    File2.json
    Subfolder1
        File3.csv
        File4.json
        File5.csv
AnotherFolderB
    File6.csv
Folder* *.csv true FolderA
    File1.csv
    File2.json
    Subfolder1
        File3.csv
        File4.json
        File5.csv
AnotherFolderB
    File6.csv

File list examples

This section describes the resulting behavior of using file list path in copy activity source.

Assuming you have the following source folder structure and want to copy the files in bold:

Sample source structure Content in FileListToCopy.txt ADF configuration
root
    FolderA
        File1.csv
        File2.json
        Subfolder1
            File3.csv
            File4.json
            File5.csv
    Metadata
        FileListToCopy.txt
File1.csv
Subfolder1/File3.csv
Subfolder1/File5.csv
In dataset:
- Folder path: root/FolderA

In copy activity source:
- File list path: root/Metadata/FileListToCopy.txt

The file list path points to a text file in the same data store that includes a list of files you want to copy, one file per line with the relative path to the path configured in the dataset.

recursive and copyBehavior examples

This section describes the resulting behavior of the Copy operation for different combinations of recursive and copyBehavior values.

recursive copyBehavior Source folder structure Resulting target
true preserveHierarchy Folder1
    File1
    File2
    Subfolder1
        File3
        File4
        File5
The target folder Folder1 is created with the same structure as the source:

Folder1
    File1
    File2
    Subfolder1
        File3
        File4
        File5.
true flattenHierarchy Folder1
    File1
    File2
    Subfolder1
        File3
        File4
        File5
The target Folder1 is created with the following structure:

Folder1
    autogenerated name for File1
    autogenerated name for File2
    autogenerated name for File3
    autogenerated name for File4
    autogenerated name for File5
true mergeFiles Folder1
    File1
    File2
    Subfolder1
        File3
        File4
        File5
The target Folder1 is created with the following structure:

Folder1
    File1 + File2 + File3 + File4 + File 5 contents are merged into one file with autogenerated file name
false preserveHierarchy Folder1
    File1
    File2
    Subfolder1
        File3
        File4
        File5
The target folder Folder1 is created with the following structure

Folder1
    File1
    File2

Subfolder1 with File3, File4, and File5 are not picked up.
false flattenHierarchy Folder1
    File1
    File2
    Subfolder1
        File3
        File4
        File5
The target folder Folder1 is created with the following structure

Folder1
    autogenerated name for File1
    autogenerated name for File2

Subfolder1 with File3, File4, and File5 are not picked up.
false mergeFiles Folder1
    File1
    File2
    Subfolder1
        File3
        File4
        File5
The target folder Folder1 is created with the following structure

Folder1
    File1 + File2 contents are merged into one file with autogenerated file name. autogenerated name for File1

Subfolder1 with File3, File4, and File5 are not picked up.

Lookup activity properties

To learn details about the properties, check Lookup activity.

GetMetadata activity properties

To learn details about the properties, check GetMetadata activity

Delete activity properties

To learn details about the properties, check Delete activity

Legacy models

Note

The following models are still supported as-is for backward compatibility. You are suggested to use the new model mentioned in above sections going forward, and the ADF authoring UI has switched to generating the new model.

Legacy dataset model

Property Description Required
type The type property of the dataset must be set to: FileShare Yes
folderPath Path to the folder.

Wildcard filter is supported, allowed wildcards are: * (matches zero or more characters) and ? (matches zero or single character); use ^ to escape if your actual folder name has wildcard or this escape char inside.

Examples: rootfolder/subfolder/, see more examples in Folder and file filter examples.
Yes
fileName Name or wildcard filter for the file(s) under the specified "folderPath". If you don't specify a value for this property, the dataset points to all files in the folder.

For filter, allowed wildcards are: * (matches zero or more characters) and ? (matches zero or single character).
- Example 1: "fileName": "*.csv"
- Example 2: "fileName": "???20180427.txt"
Use ^ to escape if your actual file name has wildcard or this escape char inside.

When fileName isn't specified for an output dataset and preserveHierarchy isn't specified in the activity sink, the copy activity automatically generates the file name with the following pattern: "Data.[activity run ID GUID].[GUID if FlattenHierarchy].[format if configured].[compression if configured]", for example "Data.0a405f8a-93ff-4c6f-b3be-f69616f1df7a.txt.gz"; if you copy from tabular source using table name instead of query, the name pattern is "[table name].[format].[compression if configured]", for example "MyTable.csv".
No
modifiedDatetimeStart Files filter based on the attribute: Last Modified. The files will be selected if their last modified time is within the time range between modifiedDatetimeStart and modifiedDatetimeEnd. The time is applied to UTC time zone in the format of "2018-12-01T05:00:00Z".

Be aware the overall performance of data movement will be impacted by enabling this setting when you want to do file filter from huge amounts of files.

The properties can be NULL that means no file attribute filter will be applied to the dataset. When modifiedDatetimeStart has datetime value but modifiedDatetimeEnd is NULL, it means the files whose last modified attribute is greater than or equal with the datetime value will be selected. When modifiedDatetimeEnd has datetime value but modifiedDatetimeStart is NULL, it means the files whose last modified attribute is less than the datetime value will be selected.
No
modifiedDatetimeEnd Files filter based on the attribute: Last Modified. The files will be selected if their last modified time is within the time range between modifiedDatetimeStart and modifiedDatetimeEnd. The time is applied to UTC time zone in the format of "2018-12-01T05:00:00Z".

Be aware the overall performance of data movement will be impacted by enabling this setting when you want to do file filter from huge amounts of files.

The properties can be NULL that means no file attribute filter will be applied to the dataset. When modifiedDatetimeStart has datetime value but modifiedDatetimeEnd is NULL, it means the files whose last modified attribute is greater than or equal with the datetime value will be selected. When modifiedDatetimeEnd has datetime value but modifiedDatetimeStart is NULL, it means the files whose last modified attribute is less than the datetime value will be selected.
No
format If you want to copy files as-is between file-based stores (binary copy), skip the format section in both input and output dataset definitions.

If you want to parse or generate files with a specific format, the following file format types are supported: TextFormat, JsonFormat, AvroFormat, OrcFormat, ParquetFormat. Set the type property under format to one of these values. For more information, see Text Format, Json Format, Avro Format, Orc Format, and Parquet Format sections.
No (only for binary copy scenario)
compression Specify the type and level of compression for the data. For more information, see Supported file formats and compression codecs.
Supported types are: GZip, Deflate, BZip2, and ZipDeflate.
Supported levels are: Optimal and Fastest.
No

Tip

To copy all files under a folder, specify folderPath only.
To copy a single file with a given name, specify folderPath with folder part and fileName with file name.
To copy a subset of files under a folder, specify folderPath with folder part and fileName with wildcard filter.

Note

If you were using "fileFilter" property for file filter, it is still supported as-is, while you are suggested to use the new filter capability added to "fileName" going forward.

Example:

{
    "name": "AzureFileStorageDataset",
    "properties": {
        "type": "FileShare",
        "linkedServiceName":{
            "referenceName": "<Azure File Storage linked service name>",
            "type": "LinkedServiceReference"
        },
        "typeProperties": {
            "folderPath": "folder/subfolder/",
            "fileName": "*",
            "modifiedDatetimeStart": "2018-12-01T05:00:00Z",
            "modifiedDatetimeEnd": "2018-12-01T06:00:00Z",
            "format": {
                "type": "TextFormat",
                "columnDelimiter": ",",
                "rowDelimiter": "\n"
            },
            "compression": {
                "type": "GZip",
                "level": "Optimal"
            }
        }
    }
}

Legacy copy activity source model

Property Description Required
type The type property of the copy activity source must be set to: FileSystemSource Yes
recursive Indicates whether the data is read recursively from the sub folders or only from the specified folder. Note when recursive is set to true and sink is file-based store, empty folder/sub-folder will not be copied/created at sink.
Allowed values are: true (default), false
No
maxConcurrentConnections The number of the connections to connect to storage store concurrently. Specify only when you want to limit the concurrent connection to the data store. No

Example:

"activities":[
    {
        "name": "CopyFromAzureFileStorage",
        "type": "Copy",
        "inputs": [
            {
                "referenceName": "<Azure File Storage input dataset name>",
                "type": "DatasetReference"
            }
        ],
        "outputs": [
            {
                "referenceName": "<output dataset name>",
                "type": "DatasetReference"
            }
        ],
        "typeProperties": {
            "source": {
                "type": "FileSystemSource",
                "recursive": true
            },
            "sink": {
                "type": "<sink type>"
            }
        }
    }
]

Legacy copy activity sink model

Property Description Required
type The type property of the copy activity sink must be set to: FileSystemSink Yes
copyBehavior Defines the copy behavior when the source is files from file-based data store.

Allowed values are:
- PreserveHierarchy (default): preserves the file hierarchy in the target folder. The relative path of source file to source folder is identical to the relative path of target file to target folder.
- FlattenHierarchy: all files from the source folder are in the first level of target folder. The target files have autogenerated name.
- MergeFiles: merges all files from the source folder to one file. If the File Name is specified, the merged file name would be the specified name; otherwise, would be autogenerated file name.
No
maxConcurrentConnections The number of the connections to connect to storage store concurrently. Specify only when you want to limit the concurrent connection to the data store. No

Example:

"activities":[
    {
        "name": "CopyToAzureFileStorage",
        "type": "Copy",
        "inputs": [
            {
                "referenceName": "<input dataset name>",
                "type": "DatasetReference"
            }
        ],
        "outputs": [
            {
                "referenceName": "<Azure File Storage output dataset name>",
                "type": "DatasetReference"
            }
        ],
        "typeProperties": {
            "source": {
                "type": "<source type>"
            },
            "sink": {
                "type": "FileSystemSink",
                "copyBehavior": "PreserveHierarchy"
            }
        }
    }
]

Next steps

For a list of data stores supported as sources and sinks by the copy activity in Azure Data Factory, see supported data stores.