Copy data from Google Cloud Storage using Azure Data Factory or Synapse Analytics

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APPLIES TO: Azure Data Factory Azure Synapse Analytics

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This article outlines how to copy data from Google Cloud Storage (GCS). To learn more, read the introductory articles for Azure Data Factory and Synapse Analytics.

Supported capabilities

This Google Cloud Storage connector is supported for the following capabilities:

Supported capabilities IR
Copy activity (source/-) ① ②
Lookup activity ① ②
GetMetadata activity ① ②
Delete activity ① ②

① Azure integration runtime ② Self-hosted integration runtime

Specifically, this Google Cloud Storage connector supports copying files as is or parsing files with the supported file formats and compression codecs. It takes advantage of GCS's S3-compatible interoperability.

Prerequisites

The following setup is required on your Google Cloud Storage account:

  1. Enable interoperability for your Google Cloud Storage account
  2. Set the default project that contains the data you want to copy from the target GCS bucket.
  3. Create a service account and define the right levels of permissions by using Cloud IAM on GCP.
  4. Generate the access keys for this service account.

Retrieve access key for Google Cloud Storage

Required permissions

To copy data from Google Cloud Storage, make sure you've been granted the following permissions for object operations: storage.objects.get and storage.objects.list.

If you use UI to author, additional storage.buckets.list permission is required for operations like testing connection to linked service and browsing from root. If you don't want to grant this permission, you can choose "Test connection to file path" or "Browse from specified path" options from the UI.

For the full list of Google Cloud Storage roles and associated permissions, see IAM roles for Cloud Storage on the Google Cloud site.

Getting started

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

Create a linked service to Google Cloud Storage using UI

Use the following steps to create a linked service to Google Cloud Storage in the Azure portal UI.

  1. Browse to the Manage tab in your Azure Data Factory or Synapse workspace and select Linked Services, then click New:

  2. Search for Google and select the Google Cloud Storage (S3 API) connector.

    Select the Google Cloud Storage (S3 API) connector.

  3. Configure the service details, test the connection, and create the new linked service.

    Configure a linked service to Google Cloud Storage.

Connector configuration details

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

Linked service properties

The following properties are supported for Google Cloud Storage linked services:

Property Description Required
type The type property must be set to GoogleCloudStorage. Yes
accessKeyId ID of the secret access key. To find the access key and secret, see Prerequisites. Yes
secretAccessKey The secret access key itself. Mark this field as SecureString to store it securely, or reference a secret stored in Azure Key Vault. Yes
serviceUrl Specify the custom GCS endpoint as https://storage.googleapis.com. Yes
connectVia The integration runtime to be used to connect to the data store. You can use the Azure integration runtime or the self-hosted integration runtime (if your data store is in a private network). If this property isn't specified, the service uses the default Azure integration runtime. No

Here's an example:

{
    "name": "GoogleCloudStorageLinkedService",
    "properties": {
        "type": "GoogleCloudStorage",
        "typeProperties": {
            "accessKeyId": "<access key id>",
            "secretAccessKey": {
                "type": "SecureString",
                "value": "<secret access key>"
            },
            "serviceUrl": "https://storage.googleapis.com"
        },
        "connectVia": {
            "referenceName": "<name of Integration Runtime>",
            "type": "IntegrationRuntimeReference"
        }
    }
}

Dataset properties

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

The following properties are supported for Google Cloud Storage under location settings in a format-based dataset:

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

Example:

{
    "name": "DelimitedTextDataset",
    "properties": {
        "type": "DelimitedText",
        "linkedServiceName": {
            "referenceName": "<Google Cloud Storage linked service name>",
            "type": "LinkedServiceReference"
        },
        "schema": [ < physical schema, optional, auto retrieved during authoring > ],
        "typeProperties": {
            "location": {
                "type": "GoogleCloudStorageLocation",
                "bucketName": "bucketname",
                "folderPath": "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 that the Google Cloud Storage source supports.

Google Cloud Storage as a source type

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

The following properties are supported for Google Cloud Storage under storeSettings settings in a format-based copy source:

Property Description Required
type The type property under storeSettings must be set to GoogleCloudStorageReadSettings. Yes
Locate the files to copy:
OPTION 1: static path
 Copy from the given bucket or folder/file path specified in the dataset. If you want to copy all files from a bucket or folder, additionally specify wildcardFileName as *.
OPTION 2: GCS prefix
- prefix		 Prefix for the GCS key name under the given bucket configured in the dataset to filter source GCS files. GCS keys whose names start with bucket_in_dataset/this_prefix are selected. It utilizes GCS's service-side filter, which provides better performance than a wildcard filter. No
OPTION 3: wildcard
- wildcardFolderPath		 The folder path with wildcard characters under the given bucket configured in a dataset to filter source folders.
Allowed wildcards are: * (matches zero or more characters) and ? (matches zero or single character). Use ^ to escape if your folder name has a wildcard or this escape character inside.
See more examples in Folder and file filter examples.		 No
OPTION 3: wildcard
- wildcardFileName		 The file name with wildcard characters under the given bucket and folder path (or wildcard folder path) to filter source files.
Allowed wildcards are: * (matches zero or more characters) and ? (matches zero or single character). Use ^ to escape if your file name has a wildcard or this escape character 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 you're using this option, do not specify the file name in the 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 files copy scenario. The default value: false.		 No
modifiedDatetimeStart Files are filtered based on the attribute: last modified.
The files will be selected if their last modified time is greater than or equal to modifiedDatetimeStart and less than modifiedDatetimeEnd. The time is applied to the 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 a datetime value but modifiedDatetimeEnd is NULL, the files whose last modified attribute is greater than or equal to the datetime value will be selected. When modifiedDatetimeEnd has a datetime value but modifiedDatetimeStart is NULL, 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
enablePartitionDiscovery For files that are partitioned, specify whether to parse the partitions from the file path and add them as additional source columns.
Allowed values are false (default) and true.		 No
partitionRootPath When partition discovery is enabled, specify the absolute root path in order to read partitioned folders as data columns.

If it is not specified, by default,
- When you use file path in dataset or list of files on source, partition root path is the path configured in dataset.
- When you use wildcard folder filter, partition root path is the sub-path before the first wildcard.

For example, assuming you configure the path in dataset as "root/folder/year=2020/month=08/day=27":
- If you specify partition root path as "root/folder/year=2020", copy activity will generate two more columns month and day with value "08" and "27" respectively, in addition to the columns inside the files.
- If partition root path is not specified, no extra column will be generated.		 No
maxConcurrentConnections The upper limit of concurrent connections established to the data store during the activity run. Specify a value only when you want to limit concurrent connections. No

Example:

"activities":[
    {
        "name": "CopyFromGoogleCloudStorage",
        "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": "GoogleCloudStorageReadSettings",
                    "recursive": true,
                    "wildcardFolderPath": "myfolder*A",
                    "wildcardFileName": "*.csv"
                }
            },
            "sink": {
                "type": "<sink type>"
            }
        }
    }
]

Folder and file filter examples

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

bucket key recursive Source folder structure and filter result (files in bold are retrieved)
bucket Folder*/* false bucket
    FolderA
        File1.csv
        File2.json
        Subfolder1
            File3.csv
            File4.json
            File5.csv
    AnotherFolderB
        File6.csv
bucket Folder*/* true bucket
    FolderA
        File1.csv
        File2.json
        Subfolder1
            File3.csv
            File4.json
            File5.csv
    AnotherFolderB
        File6.csv
bucket Folder*/*.csv false bucket
    FolderA
        File1.csv
        File2.json
        Subfolder1
            File3.csv
            File4.json
            File5.csv
    AnotherFolderB
        File6.csv
bucket Folder*/*.csv true bucket
    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 a file list path in the Copy activity source.

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

Sample source structure Content in FileListToCopy.txt Configuration
bucket
    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:
- Bucket: bucket
- Folder path: FolderA

In copy activity source:
- File list path: bucket/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.

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

If you were using an Amazon S3 connector to copy data from Google Cloud Storage, it's still supported as is for backward compatibility. We suggest that you use the new model mentioned earlier. The authoring UI has switched to generating the new model.

Related content

For a list of data stores that the Copy activity supports as sources and sinks, see Supported data stores.