Add the polyglot python-task sample

dataflow-website/recipes/polyglot/polyglot-python-task/util/task_args.py

@@ -0,0 +1,53 @@
+import sys
+from collections import defaultdict
+
+
+def get_cmd_arg(name):
+    """Extracts argument value by name. (@author: Chris Schaefer)
+  
+    Assumes the exec (default) spring-cloud-deployer-k8s argument passing mode.
+  
+    Args:
+      name: argument name.
+    Returns:
+      value of the requested argument.
+    """
+    d = defaultdict(list)
+    for k, v in ((k.lstrip('-'), v) for k, v in (a.split('=') for a in sys.argv[1:])):
+        d[k].append(v)
+
+    return d[name][0]
+
+
+def get_db_url():
+    """Computes sqlalchemy connection URL
+  
+    Uses the s.d.username, s.d.password and s.d.url properties to compute the sqlalchemy url.
+    This provides access to the SCDF internal DB and tables such as TASK_EXECUTION. 
+
+    Returns:
+      sqlalchemy compatible URL compatible with the target DB.
+    """
+    username = get_cmd_arg('spring.datasource.username')
+    password = get_cmd_arg('spring.datasource.password')
+    jdbc_url = get_cmd_arg('spring.datasource.url')
+
+    return str(jdbc_url) \
+        .replace('jdbc:', '') \
+        .replace('sqlserver:', 'mssql+pyodbc:') \
+        .replace('//', '//{username}:{password}@'.format(username=username, password=password))
+
+
+def get_task_id():
+    """Task ID as handled inside SCDF.
+  
+    When launching tasks SCDF provides the spring.cloud.task.executionid as command line argument.  
+
+    Returns:
+      The task id as handled inside SCDF.
+    """
+    return get_cmd_arg('spring.cloud.task.executionid')
+
+
+def get_task_name():
+    return get_cmd_arg('spring.cloud.task.name')

dataflow-website/recipes/polyglot/polyglot-python-task/util/task_status.py

@@ -0,0 +1,40 @@
+from sqlalchemy import create_engine
+from sqlalchemy.sql import text
+import datetime
+
+
+class TaskStatus:
+    """Helper class to help manage Task's status in the SCDF DB. """
+
+    def __init__(self, task_id, jdbc_url):
+        self.task_id = task_id
+        self.engine = create_engine(jdbc_url)
+        self.connection = self.engine.connect()
+
+    def running(self):
+        """Set the TASK_EXECUTION's START_TIME """
+        now = datetime.datetime.now()
+        start_task_statement = text(
+            "UPDATE TASK_EXECUTION SET START_TIME=:start_time, EXIT_CODE=null, LAST_UPDATED=:last_updated  "
+            "WHERE TASK_EXECUTION_ID=:task_id")
+        self.connection.execute(start_task_statement, start_time=now, last_updated=now, task_id=self.task_id)
+
+    def completed(self):
+        """Set the TASK_EXECUTION's END_TIME, EXIST_CODE=0 and EXIST_MESSAGE/ERROR_MESSAGE must be null """
+        now = datetime.datetime.now()
+        complete_task_statement = text(
+            "UPDATE TASK_EXECUTION SET END_TIME=:end_time, EXIT_CODE=0, EXIT_MESSAGE=null, ERROR_MESSAGE=null, "
+            "LAST_UPDATED=:last_updated  WHERE TASK_EXECUTION_ID=:task_id")
+        self.connection.execute(complete_task_statement, end_time=now, last_updated=now, task_id=self.task_id)
+
+    def failed(self, exit_code, exit_message, error_message=''):
+        """Set the TASK_EXECUTION's END_TIME, EXIST_CODE is the error code and EXIST_MESSAGE/ERROR_MESSAGE describe
+        the error """
+        now = datetime.datetime.now()
+        complete_task_statement = text(
+            "UPDATE TASK_EXECUTION SET END_TIME=:end_time, EXIT_CODE=:exit_code, EXIT_MESSAGE=:exit_message, "
+            "  ERROR_MESSAGE=:error_message, LAST_UPDATED=:last_updated  "
+            "WHERE TASK_EXECUTION_ID=:task_id")
+        self.connection.execute(complete_task_statement, end_time=now, exit_code=exit_code,
+                                exit_message=exit_message, error_message=error_message, last_updated=now,
+                                task_id=self.task_id)