Managing data loading and unloading resources with Python (original) (raw)

You can use Python to manage data loading and unloading resources in Snowflake, including external volumes, pipes, and stages.

Prerequisites¶

The examples in this topic assume that you’ve added code to connect with Snowflake and to create a Root object from which to use the Snowflake Python APIs.

For example, the following code uses connection parameters defined in a configuration file to create a connection to Snowflake:

from snowflake.core import Root from snowflake.snowpark import Session

session = Session.builder.config("connection_name", "myconnection").create() root = Root(session)

Using the resulting Session object, the code creates a Root object to use the API’s types and methods. For more information, see Connect to Snowflake with the Snowflake Python APIs.

Managing stages¶

You can manage Snowflake stages, which are locations of data files in cloud storage. For an overview of stages, seeOverview of data loading.

The Snowflake Python APIs represents stages with two separate types:

Stage: Exposes a stage’s properties such as its name, encryption type, credentials, and directory table settings.
StageResource: Exposes methods you can use to fetch a corresponding Stage object, upload and list files on the stage, and drop the stage.

Creating a stage¶

To create a stage, first create a Stage object, and then create a StageCollection object from the API Rootobject. Using StageCollection.create, add the new stage to Snowflake.

Code in the following example creates a Stage object that represents a stage named my_stage with an encryption type ofSNOWFLAKE_SSE (server-side encryption only):

from snowflake.core.stage import Stage, StageEncryption

my_stage = Stage( name="my_stage", encryption=StageEncryption(type="SNOWFLAKE_SSE") ) stages = root.databases["my_db"].schemas["my_schema"].stages stages.create(my_stage)

The code creates a StageCollection variable stages and uses StageCollection.create to create a new stage in Snowflake.

Getting stage details¶

You can get information about a stage by calling the StageResource.fetch method, which returns a Stage object.

Code in the following example gets information about a stage named my_stage:

my_stage = root.databases["my_db"].schemas["my_schema"].stages["my_stage"].fetch() print(my_stage.to_dict())

Listing stages¶

You can list stages using the StageCollection.iter method, which returns a PagedIter iterator of Stage objects.

Code in the following example lists stages whose name includes the text my and prints the name of each:

from snowflake.core.stage import StageCollection

stages: StageCollection = root.databases["my_db"].schemas["my_schema"].stages stage_iter = stages.iter(like="my%") # returns a PagedIter[Stage] for stage_obj in stage_iter: print(stage_obj.name)

Performing stage operations¶

You can perform common stage operations—such as uploading a file to a stage and listing files on a stage—with a StageResourceobject.

To demonstrate some operations you can do with a stage resource, code in the following example does the following:

Uploads a file named my-file.yaml to the my_stage stage with the specified auto-compress and overwrite options.
Lists all files on the stage to verify that the file was uploaded successfully.
Drops the stage.

my_stage_res = root.databases["my_db"].schemas["my_schema"].stages["my_stage"]

my_stage_res.put("./my-file.yaml", "/", auto_compress=False, overwrite=True)

stageFiles = root.databases["my_db"].schemas["my_schema"].stages["my_stage"].list_files() for stageFile in stageFiles: print(stageFile)

my_stage_res.drop()

Managing pipes¶

You can manage Snowflake pipes, which are named, first-class Snowflake objects that contain a COPY INTO statement used by Snowpipe to load data from an ingestion queue into tables. For an overview of pipes, see Snowpipe.

The Snowflake Python APIs represents pipes with two separate types:

Pipe: Exposes a pipe’s properties such as its name and the COPY INTO statement to be used by Snowpipe.
PipeResource: Exposes methods you can use to fetch a corresponding Pipe object, refresh the pipe with staged data files, and drop the pipe.

Creating a pipe¶

To create a pipe, first create a Pipe object, and then create a PipeCollection object from the API Rootobject. Using PipeCollection.create, add the new pipe to Snowflake.

Code in the following example creates a Pipe object that represents a pipe named my_pipe with the specified COPY INTO statement:

from snowflake.core.pipe import Pipe

my_pipe = Pipe( name="my_pipe", comment="creating my pipe", copy_statement="COPY INTO my_table FROM @mystage FILE_FORMAT = (TYPE = 'JSON')", )

pipes = root.databases["my_db"].schemas["my_schema"].pipes pipes.create(my_pipe)

The code creates a PipeCollection variable pipes and uses PipeCollection.create to create a new pipe in Snowflake.

Getting pipe details¶

You can get information about a pipe by calling the PipeResource.fetch method, which returns a Pipe object.

Code in the following example gets information about a pipe named my_pipe:

my_pipe = root.databases["my_db"].schemas["my_schema"].pipes["my_pipe"].fetch() print(my_pipe.to_dict())

Listing pipes¶

You can list pipes using the PipeCollection.iter method, which returns a PagedIter iterator of Pipe objects.

Code in the following example lists pipes whose name starts with my and prints the name of each:

from snowflake.core.pipe import PipeCollection

pipes: PipeCollection = root.databases["my_db"].schemas["my_schema"].pipes pipe_iter = pipes.iter(like="my%") # returns a PagedIter[Pipe] for pipe_obj in pipe_iter: print(pipe_obj.name)

Performing pipe operations¶

You can perform common pipe operations—such as refreshing a pipe and dropping a pipe—with a PipeResource object.

Note

Only the REFRESH functionality of ALTER PIPE is currently supported.

To demonstrate operations you can do with a pipe resource, code in the following example does the following:

Gets the my_pipe pipe resource object.
Refreshes the pipe with staged data files with the specified, optional prefix (or path).
Drops the pipe.

my_pipe_res = root.databases["my_db"].schemas["my_schema"].pipes["my_pipe"]

equivalent to: ALTER PIPE my_pipe REFRESH PREFIX = 'dir3/'

my_pipe_res.refresh(prefix="dir3/")

my_pipe_res.drop()

Managing external volumes¶

You can manage external volumes, which are named, account-level Snowflake objects that you use to connect Snowflake to your external cloud storage for Apache Iceberg™ tables. For more information, see the External volume section ofApache Iceberg™ tables.

The Snowflake Python APIs represents external volumes with two separate types:

ExternalVolume: Exposes an external volume’s properties, such as its name and storage locations.
ExternalVolumeResource: Exposes methods you can use to fetch a corresponding ExternalVolume object and drop or restore the external volume.

Creating an external volume¶

To create an external volume, first create an ExternalVolume object, and then create an ExternalVolumeCollection object from the API Root object. Using ExternalVolumeCollection.create, add the new external volume to Snowflake.

Code in the following example creates an ExternalVolume object that represents an external volume named my_external_volumewith the specified AWS S3 storage locations:

from snowflake.core.external_volume import ( ExternalVolume, StorageLocationS3, )

my_external_volume = ExternalVolume( name="my_external_volume", storage_locations=[ StorageLocationS3( name="my-s3-us-west-1", storage_base_url="s3://MY_EXAMPLE_BUCKET/", storage_aws_role_arn="arn:aws:iam::123456789012:role/myrole", encryption=Encryption(type="AWS_SSE_KMS", kms_key_id="1234abcd-12ab-34cd-56ef-1234567890ab"), ), StorageLocationS3( name="my-s3-us-west-2", storage_base_url="s3://MY_EXAMPLE_BUCKET/", storage_aws_role_arn="arn:aws:iam::123456789012:role/myrole", encryption=Encryption(type="AWS_SSE_KMS", kms_key_id="1234abcd-12ab-34cd-56ef-1234567890ab"), ), ] )

root.external_volumes.create(my_external_volume)

Getting external volume details¶

You can get information about an external volume by calling the ExternalVolumeResource.fetch method, which returns anExternalVolume object.

Code in the following example gets information about an external volume named my_external_volume:

my_external_volume = root.external_volumes["my_external_volume"].fetch() print(my_external_volume.to_dict())

Listing external volumes¶

You can list external volumes using the ExternalVolumeCollection.iter method, which returns a PagedIter iterator ofExternalVolume objects.

Code in the following example lists external volumes whose name starts with my and prints the name of each:

external_volume_iter = root.external_volumes.iter(like="my%") for external_volume_obj in external_volume_iter: print(external_volume_obj.name)

Performing external volume operations¶

You can perform common external volume operations—such as dropping and restoring an external volume—with anExternalVolumeResource object.

To demonstrate operations you can do with an external volume resource, code in the following example does the following:

Gets the my_external_volume external volume resource object.
Drops the external volume.
Restores the most recent version of the dropped external volume.

my_external_volume_res = root.external_volumes["my_external_volume"] my_external_volume_res.drop() my_external_volume_res.undrop()