Added exception handling

Co-authored-by: Danijel Schorlemmer <ds@gfz-potsdam.de>

.gitignore

+build
+dist
+
+*.pyc
+*.log
+*.pkl
+*.egg-info
+Pipfile
+Pipfile.lock
+
+
+__pycache__
+.cache
+.flycheck*

exposurelib/database.py

@@ -64,19 +64,37 @@ class SpatialiteDatabase:
 
         # Connect (if exists) or create SQLite database
         logger.debug("Connecting to database at %s" % self.database_filepath)
-        self.connection = sqlite3.connect(self.database_filepath)
+        try:
+            self.connection = sqlite3.connect(self.database_filepath)
+        except Exception:
+            logger.exception("Error connecting to the database file")
+            raise
         logger.debug("Connection to database established")
 
         # Load and initialize the Spatialite extension
         self.connection.enable_load_extension(True)
         sql_statement = "SELECT load_extension('%s');" % self.spatialite_filepath
-        self.connection.execute(sql_statement)
+        try:
+            self.connection.execute(sql_statement)
+        except sqlite3.OperationalError:
+            logger.exception("Error loading spatial extension")
+            raise
+        logger.debug("Spatialite extension loaded")
+
         if init_spatial_metadata:
-            self.connection.execute("SELECT InitSpatialMetaData(1);")
-            logger.debug("Spatialite extension loaded and initialized")
+            try:
+                self.connection.execute("SELECT InitSpatialMetaData(1);")
+            except Exception:
+                logger.exception("Error initializing spatial metadata")
+                raise
+            logger.debug("Spatial metadata initialized")
 
         # Debug output
-        versions = self.connection.execute("SELECT sqlite_version(), spatialite_version()")
+        try:
+            versions = self.connection.execute("SELECT sqlite_version(), spatialite_version()")
+        except Exception:
+            logger.exception("Error querying database versions")
+            raise
         for row in versions:
             logger.debug("SQLite version: %s" % row[0])
             logger.debug("Spatialite version: %s" % row[1])