# -*- coding: utf-8 -*-
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# to you under the Apache License, Version 2.0 (the
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from airflow.hooks.postgres_hook import PostgresHook
from airflow.models import BaseOperator
from airflow.utils.decorators import apply_defaults


class PostgresOperator(BaseOperator):
    """
    Executes sql code in a specific Postgres database

    :param sql: the sql code to be executed. (templated)
    :type sql: Can receive a str representing a sql statement,
        a list of str (sql statements), or reference to a template file.
        Template reference are recognized by str ending in '.sql'
    :param postgres_conn_id: reference to a specific postgres database
    :type postgres_conn_id: str
    :param autocommit: if True, each command is automatically committed.
        (default value: False)
    :type autocommit: bool
    :param parameters: (optional) the parameters to render the SQL query with.
    :type parameters: mapping or iterable
    :param database: name of database which overwrite defined one in connection
    :type database: str
    """

    template_fields = ('sql',)
    template_ext = ('.sql',)
    ui_color = '#ededed'

    @apply_defaults
    def __init__(
            self, sql,
            postgres_conn_id='postgres_default', autocommit=False,
            parameters=None,
            database=None,
            *args, **kwargs):
        super(PostgresOperator, self).__init__(*args, **kwargs)
        self.sql = sql
        self.postgres_conn_id = postgres_conn_id
        self.autocommit = autocommit
        self.parameters = parameters
        self.database = database

    def execute(self, context):
        self.log.info('Executing: %s', self.sql)
        self.hook = PostgresHook(postgres_conn_id=self.postgres_conn_id,
                                 schema=self.database)
        self.hook.run(self.sql, self.autocommit, parameters=self.parameters)
        for output in self.hook.conn.notices:
            self.log.info(output)
