Merge pull request #6470 from psa/db-exception-detail

Db exception detail

CONTRIBUTING.md

@@ -29,7 +29,7 @@ We use [semver](https://semver.org/) to separate riskier changes (e.g. new featu
 (e.g. 8.1, 8.2, 8.3)
 
 **Bugfixes** and minor usability enhancements are made on bugfix branches and
-released as the next maintainance version (e.g. 8.0.1, 8.0.2, 8.0.3). E.G. if the issue is on the `8.0.x` milestone, branch off of `8.0.x` to
+released as the next maintenance version (e.g. 8.0.1, 8.0.2, 8.0.3). E.G. if the issue is on the `8.0.x` milestone, branch off of `8.0.x` to
 develop your bugfix, then raise the pull request against the `8.0.x` branch. We will later merge the `8.0.x` branch into `master`.
 
 Feel free to ask questions on the issue or
@@ -96,6 +96,7 @@ requests_).
  - Diquan Jabbour
  - Shixian Sheng
  - Utheri Wagura
+ - Paul Armstrong
  - Paul Earnshaw
 <!-- end-shortlog -->
 

cylc/flow/rundb.py

@@ -481,7 +481,7 @@ def execute_queued_items(self):
 
         # something went wrong
         # (includes DB file not found, transaction processing issue, db locked)
-        except sqlite3.Error:
+        except sqlite3.Error as e:
             if not self.is_public:
                 # incase this isn't a filesystem issue, log the statements
                 # which make up the transaction to assist debug
@@ -493,8 +493,13 @@ def execute_queued_items(self):
                 raise
             self.n_tries += 1
             LOG.warning(
-                "%(file)s: write attempt (%(attempt)d) did not complete\n" % {
-                    "file": self.db_file_name, "attempt": self.n_tries})
+                "%(file)s: write attempt (%(attempt)d)"
+                " did not complete: %(error)s\n" % {
+                    "file": self.db_file_name,
+                    "attempt": self.n_tries,
+                    "error": str(e)
+                }
+            )
             if self.conn is not None:
                 with suppress(sqlite3.Error):
                     self.conn.rollback()