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# to you under the Apache License, Version 2.0 (the
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#
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import json
import os
import warnings
from typing import Any, Callable, Iterable, Optional, overload
import trino
from trino.exceptions import DatabaseError
from trino.transaction import IsolationLevel
from airflow import AirflowException
from airflow.configuration import conf
from airflow.hooks.dbapi import DbApiHook
from airflow.models import Connection
from airflow.utils.operator_helpers import AIRFLOW_VAR_NAME_FORMAT_MAPPING
try:
from airflow.utils.operator_helpers import DEFAULT_FORMAT_PREFIX
except ImportError:
# This is from airflow.utils.operator_helpers,
# For the sake of provider backward compatibility, this is hardcoded if import fails
# https://github.com/apache/airflow/pull/22416#issuecomment-1075531290
[docs]def generate_trino_client_info() -> str:
"""Return json string with dag_id, task_id, execution_date and try_number"""
context_var = {
format_map['default'].replace(DEFAULT_FORMAT_PREFIX, ''): os.environ.get(
format_map['env_var_format'], ''
)
for format_map in AIRFLOW_VAR_NAME_FORMAT_MAPPING.values()
}
task_info = {
'dag_id': context_var['dag_id'],
'task_id': context_var['task_id'],
'execution_date': context_var['execution_date'],
'try_number': context_var['try_number'],
'dag_run_id': context_var['dag_run_id'],
'dag_owner': context_var['dag_owner'],
}
return json.dumps(task_info, sort_keys=True)
[docs]class TrinoException(Exception):
"""Trino exception"""
def _boolify(value):
if isinstance(value, bool):
return value
if isinstance(value, str):
if value.lower() == 'false':
return False
elif value.lower() == 'true':
return True
return value
[docs]class TrinoHook(DbApiHook):
"""
Interact with Trino through trino package.
>>> ph = TrinoHook()
>>> sql = "SELECT count(1) AS num FROM airflow.static_babynames"
>>> ph.get_records(sql)
[[340698]]
"""
[docs] conn_name_attr = 'trino_conn_id'
[docs] default_conn_name = 'trino_default'
[docs] def get_conn(self) -> Connection:
"""Returns a connection object"""
db = self.get_connection(self.trino_conn_id) # type: ignore[attr-defined]
extra = db.extra_dejson
auth = None
if db.password and extra.get('auth') == 'kerberos':
raise AirflowException("Kerberos authorization doesn't support password.")
elif db.password:
auth = trino.auth.BasicAuthentication(db.login, db.password)
elif extra.get('auth') == 'kerberos':
auth = trino.auth.KerberosAuthentication(
config=extra.get('kerberos__config', os.environ.get('KRB5_CONFIG')),
service_name=extra.get('kerberos__service_name'),
mutual_authentication=_boolify(extra.get('kerberos__mutual_authentication', False)),
force_preemptive=_boolify(extra.get('kerberos__force_preemptive', False)),
hostname_override=extra.get('kerberos__hostname_override'),
sanitize_mutual_error_response=_boolify(
extra.get('kerberos__sanitize_mutual_error_response', True)
),
principal=extra.get('kerberos__principal', conf.get('kerberos', 'principal')),
delegate=_boolify(extra.get('kerberos__delegate', False)),
ca_bundle=extra.get('kerberos__ca_bundle'),
)
http_headers = {"X-Trino-Client-Info": generate_trino_client_info()}
trino_conn = trino.dbapi.connect(
host=db.host,
port=db.port,
user=db.login,
source=extra.get('source', 'airflow'),
http_scheme=extra.get('protocol', 'http'),
http_headers=http_headers,
catalog=extra.get('catalog', 'hive'),
schema=db.schema,
auth=auth,
isolation_level=self.get_isolation_level(), # type: ignore[func-returns-value]
verify=_boolify(extra.get('verify', True)),
)
return trino_conn
[docs] def get_isolation_level(self) -> Any:
"""Returns an isolation level"""
db = self.get_connection(self.trino_conn_id) # type: ignore[attr-defined]
isolation_level = db.extra_dejson.get('isolation_level', 'AUTOCOMMIT').upper()
return getattr(IsolationLevel, isolation_level, IsolationLevel.AUTOCOMMIT)
@staticmethod
def _strip_sql(sql: str) -> str:
return sql.strip().rstrip(';')
@overload
def get_records(self, sql: str = "", parameters: Optional[dict] = None):
"""Get a set of records from Trino
:param sql: SQL statement to be executed.
:param parameters: The parameters to render the SQL query with.
"""
@overload
def get_records(self, sql: str = "", parameters: Optional[dict] = None, hql: str = ""):
""":sphinx-autoapi-skip:"""
def get_records(self, sql: str = "", parameters: Optional[dict] = None, hql: str = ""):
""":sphinx-autoapi-skip:"""
if hql:
warnings.warn(
"The hql parameter has been deprecated. You should pass the sql parameter.",
DeprecationWarning,
stacklevel=2,
)
sql = hql
try:
return super().get_records(self._strip_sql(sql), parameters)
except DatabaseError as e:
raise TrinoException(e)
@overload
def get_first(self, sql: str = "", parameters: Optional[dict] = None) -> Any:
"""Returns only the first row, regardless of how many rows the query returns.
:param sql: SQL statement to be executed.
:param parameters: The parameters to render the SQL query with.
"""
@overload
def get_first(self, sql: str = "", parameters: Optional[dict] = None, hql: str = "") -> Any:
""":sphinx-autoapi-skip:"""
def get_first(self, sql: str = "", parameters: Optional[dict] = None, hql: str = "") -> Any:
""":sphinx-autoapi-skip:"""
if hql:
warnings.warn(
"The hql parameter has been deprecated. You should pass the sql parameter.",
DeprecationWarning,
stacklevel=2,
)
sql = hql
try:
return super().get_first(self._strip_sql(sql), parameters)
except DatabaseError as e:
raise TrinoException(e)
@overload
def get_pandas_df(
self, sql: str = "", parameters: Optional[dict] = None, **kwargs
): # type: ignore[override]
"""Get a pandas dataframe from a sql query.
:param sql: SQL statement to be executed.
:param parameters: The parameters to render the SQL query with.
"""
@overload
def get_pandas_df(
self, sql: str = "", parameters: Optional[dict] = None, hql: str = "", **kwargs
): # type: ignore[override]
""":sphinx-autoapi-skip:"""
def get_pandas_df(
self, sql: str = "", parameters: Optional[dict] = None, hql: str = "", **kwargs
): # type: ignore[override]
""":sphinx-autoapi-skip:"""
if hql:
warnings.warn(
"The hql parameter has been deprecated. You should pass the sql parameter.",
DeprecationWarning,
stacklevel=2,
)
sql = hql
import pandas
cursor = self.get_cursor()
try:
cursor.execute(self._strip_sql(sql), parameters)
data = cursor.fetchall()
except DatabaseError as e:
raise TrinoException(e)
column_descriptions = cursor.description
if data:
df = pandas.DataFrame(data, **kwargs)
df.columns = [c[0] for c in column_descriptions]
else:
df = pandas.DataFrame(**kwargs)
return df
@overload
def run(
self,
sql: str = "",
autocommit: bool = False,
parameters: Optional[dict] = None,
handler: Optional[Callable] = None,
) -> None:
"""Execute the statement against Trino. Can be used to create views."""
@overload
def run(
self,
sql: str = "",
autocommit: bool = False,
parameters: Optional[dict] = None,
handler: Optional[Callable] = None,
hql: str = "",
) -> None:
""":sphinx-autoapi-skip:"""
def run(
self,
sql: str = "",
autocommit: bool = False,
parameters: Optional[dict] = None,
handler: Optional[Callable] = None,
hql: str = "",
) -> None:
""":sphinx-autoapi-skip:"""
if hql:
warnings.warn(
"The hql parameter has been deprecated. You should pass the sql parameter.",
DeprecationWarning,
stacklevel=2,
)
sql = hql
return super().run(
sql=self._strip_sql(sql), autocommit=autocommit, parameters=parameters, handler=handler
)
[docs] def insert_rows(
self,
table: str,
rows: Iterable[tuple],
target_fields: Optional[Iterable[str]] = None,
commit_every: int = 0,
replace: bool = False,
**kwargs,
) -> None:
"""
A generic way to insert a set of tuples into a table.
:param table: Name of the target table
:param rows: The rows to insert into the table
:param target_fields: The names of the columns to fill in the table
:param commit_every: The maximum number of rows to insert in one
transaction. Set to 0 to insert all rows in one transaction.
:param replace: Whether to replace instead of insert
"""
if self.get_isolation_level() == IsolationLevel.AUTOCOMMIT:
self.log.info(
'Transactions are not enable in trino connection. '
'Please use the isolation_level property to enable it. '
'Falling back to insert all rows in one transaction.'
)
commit_every = 0
super().insert_rows(table, rows, target_fields, commit_every, replace)