This module contains operator for copying data from Cassandra to Google Cloud Storage in JSON format.

Module Contents



Copy data from Cassandra to Google Cloud Storage in JSON format.



class*, cql, bucket, filename, schema_filename=None, approx_max_file_size_bytes=1900000000, gzip=False, cassandra_conn_id='cassandra_default', gcp_conn_id='google_cloud_default', impersonation_chain=None, query_timeout=NOT_SET, encode_uuid=True, **kwargs)[source]

Bases: airflow.models.BaseOperator

Copy data from Cassandra to Google Cloud Storage in JSON format.

Note: Arrays of arrays are not supported.

  • cql (str) – The CQL to execute on the Cassandra table.

  • bucket (str) – The bucket to upload to.

  • filename (str) – The filename to use as the object name when uploading to Google Cloud Storage. A {} should be specified in the filename to allow the operator to inject file numbers in cases where the file is split due to size.

  • schema_filename (str | None) – If set, the filename to use as the object name when uploading a .json file containing the BigQuery schema fields for the table that was dumped from MySQL.

  • approx_max_file_size_bytes (int) – This operator supports the ability to split large table dumps into multiple files (see notes in the filename param docs above). This param allows developers to specify the file size of the splits. Check to see the maximum allowed file size for a single object.

  • cassandra_conn_id (str) – Reference to a specific Cassandra hook.

  • gzip (bool) – Option to compress file for upload

  • gcp_conn_id (str) – (Optional) The connection ID used to connect to Google Cloud.

  • impersonation_chain (str | Sequence[str] | None) – Optional service account to impersonate using short-term credentials, or chained list of accounts required to get the access_token of the last account in the list, which will be impersonated in the request. If set as a string, the account must grant the originating account the Service Account Token Creator IAM role. If set as a sequence, the identities from the list must grant Service Account Token Creator IAM role to the directly preceding identity, with first account from the list granting this role to the originating account (templated).

  • query_timeout (float | None | NotSetType) – (Optional) The amount of time, in seconds, used to execute the Cassandra query. If not set, the timeout value will be set in Session.execute() by Cassandra driver. If set to None, there is no timeout.

  • encode_uuid (bool) – (Optional) Option to encode UUID or not when upload from Cassandra to GCS. Default is to encode UUID.

template_fields: Sequence[str] = ('cql', 'bucket', 'filename', 'schema_filename', 'impersonation_chain')[source]
template_ext: Sequence[str] = ('.cql',)[source]
ui_color = '#a0e08c'[source]

Derive when creating an operator.

Context is the same dictionary used as when rendering jinja templates.

Refer to get_template_context for more context.

generate_data_dict(names, values)[source]

Generate data structure that will be stored as file in GCS.


Convert value to BQ type.


Map convert_value over array.


Convert a user type to RECORD that contains n fields, where n is the number of attributes.

Each element in the user type class will be converted to its corresponding data type in BQ.


Convert a tuple to RECORD that contains n fields.

Each field will be converted to its corresponding data type in bq and will be named ‘field_<index>’, where index is determined by the order of the tuple elements defined in cassandra.


Convert a map to a repeated RECORD that contains two fields: ‘key’ and ‘value’.

Each will be converted to its corresponding data type in BQ.

classmethod generate_schema_dict(name, type_)[source]

Generate BQ schema.

classmethod get_bq_fields(type_)[source]

Convert non simple type value to BQ representation.

static is_simple_type(type_)[source]

Check if type is a simple type.

static is_array_type(type_)[source]

Check if type is an array type.

static is_record_type(type_)[source]

Check the record type.

classmethod get_bq_type(type_)[source]

Convert type to equivalent BQ type.

classmethod get_bq_mode(type_)[source]

Convert type to equivalent BQ mode.

Was this entry helpful?