Show load options on failure, close connection after ping in to_sql

Author: akariv

dataflows/processors/dumpers/to_sql.py

@@ -63,7 +63,9 @@ def __init__(self,
                                      "Please set your '%s' environment variable" % env_var)
 
             self.engine = create_engine(engine)
-            self.engine.connect()
+            # check connection
+            with self.engine.connect():
+                pass
         else:
             self.engine = engine
 

dataflows/processors/load.py

@@ -157,6 +157,13 @@ def __init__(self, load_source, name=None, resources=None, strip=True, limit_row
         }[cast_strategy or self.CAST_DO_NOTHING]
 
     def process_datapackage(self, dp: Package):
+        try:
+            return self.safe_process_datapackage(dp)
+        except Exception as e: 
+            raise e from Exception('Failed to run load with load source {!r} and options {!r}'
+                                        .format(self.load_source, self.options))
+
+    def safe_process_datapackage(self, dp: Package):
 
         # If loading from datapackage & resource iterator:
         if isinstance(self.load_source, tuple):