from datetime import timedelta
from airflow.models import DAG,Variable
from airflow.utils.dates import days_ago
from airflow.operators.python_operator import PythonOperator
from airflow.contrib.operators.ssh_operator import SSHOperator
from airflow.operators.bash_operator import BashOperator
from airflow.contrib.hooks.ssh_hook import SSHHook

FTP_SEQRUN_SERVER = Variable.get('crick_ftp_seqrun_hostname')
FTP_CONFIG_FILE = Variable.get('crick_ftp_config_file')
SEQRUN_BASE_PATH = Variable.get('seqrun_base_path')

args = {
    'owner': 'airflow',
    'start_date': days_ago(2),
    'retries': 1,
    'retry_delay': timedelta(minutes=5),
    'provide_context': True,
    'email_on_failure': False,
    'email_on_retry': False,
    'catchup': False,
    'max_active_runs': 1,
}

## SSH HOOK
orwell_ssh_hook = \
  SSHHook(
    key_file=Variable.get('hpc_ssh_key_file'),
    username=Variable.get('hpc_user'),
    remote_host=Variable.get('orwell_server_hostname'))

dag = \
  DAG(
    dag_id='dag14_crick_seqrun_transfer',
    schedule_interval=None,
    default_args=args,
    tags=['ftp', 'hpc', 'orwell'])


with dag:
  # TASK
  # check if the FTP host is alive
  ping_remote_host = \
    BashOperator(
      task_id='ping_remote_host',
      dag=dag,
      xcom_push=False,
      queue='hpc_4G',
      params={'FTP_SEQRUN_SERVER': FTP_SEQRUN_SERVER},
      bash_command='ping -c5 {{ params.FTP_SEQRUN_SERVER }}')
  # TASK
  check_and_transfer_run = \
    SSHOperator(
      task_id='check_and_transfer_run',
      dag=dag,
      pool='crick_ftp_pool',
      ssh_hook=orwell_ssh_hook,
      do_xcom_push=False,
      queue='hpc_4G',
      params={'ftp_seqrun_server': FTP_SEQRUN_SERVER,
              'seqrun_base_path': SEQRUN_BASE_PATH,
              'ftp_config_file': FTP_CONFIG_FILE,
              'seqrun_id': "{{ dag_run.conf['seqrun_id'] }}" },
      command="""
        source /home/igf/igf_code/env.sh;
        python /home/igf/igf_code/data-management-python/scripts/ftp_seqrun_transfer/transfer_seqrun_from_crick.py \
          -f {{ params.ftp_seqrun_server }} \
          -s {{ params.seqrun_id }} \
          -d {{ params.seqrun_base_path }} \
          -c {{ params.ftp_config_file }}
        """)
  ## PIPELINE
  ping_remote_host >> check_and_transfer_run