more descriptive nested lock error message

Co-authored-by: Ryan Krage <[email protected]>
braintree · Sep 8, 2023 · 7144675 · 7144675
1 parent 0149c4f
commit 7144675
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Showing 2 changed files with 14 additions and 6 deletions.
diff --git a/lib/pg_ha_migrations/safe_statements.rb b/lib/pg_ha_migrations/safe_statements.rb
@@ -606,17 +606,19 @@ def safely_acquire_lock_for_table(table, &block)
     _check_postgres_adapter!
 
     schema, table = _schema_and_table_for(table)
+    fully_qualified_table = "#{connection.quote_schema_name(schema)}.#{connection.quote_table_name(table)}"
 
     # Disallow nested locks unless targeting the same table
-    if nested_lock && Thread.current[__method__] != "#{schema}_#{table}"
-      raise PgHaMigrations::InvalidMigrationError, "Nested lock detected!"
+    if nested_lock && Thread.current[__method__] != fully_qualified_table
+      raise PgHaMigrations::InvalidMigrationError, "Nested lock detected! Cannot acquire lock on #{fully_qualified_table} while #{Thread.current[__method__]} is locked."
     else
-      Thread.current[__method__] = "#{schema}_#{table}"
+      Thread.current[__method__] = fully_qualified_table
     end
 
-    fully_qualified_table = "#{connection.quote_schema_name(schema)}.#{connection.quote_table_name(table)}"
     target_schemas_and_tables = [[schema, table]]
 
+    # Locking a partitioned table will also lock child tables (including sub-partitions),
+    # so we need to check for blocking queries on those tables as well
     if _partitioned_table?(schema, table)
       target_schemas_and_tables.concat(_partitions_for_table(schema, table, include_sub_partitions: true))
     end

diff --git a/spec/safe_statements_spec.rb b/spec/safe_statements_spec.rb
@@ -3698,11 +3698,17 @@ def up
                   # thread variable doesn't incorrectly get reset
                   expect do
                     migration.safely_acquire_lock_for_table("foo")
-                  end.to raise_error(PgHaMigrations::InvalidMigrationError, "Nested lock detected!")
+                  end.to raise_error(
+                    PgHaMigrations::InvalidMigrationError,
+                    "Nested lock detected! Cannot acquire lock on \"public\".\"foo\" while \"public\".\"bogus_table\" is locked."
+                  )
 
                   migration.safely_acquire_lock_for_table("foo")
                 end
-              end.to raise_error(PgHaMigrations::InvalidMigrationError, "Nested lock detected!")
+              end.to raise_error(
+                PgHaMigrations::InvalidMigrationError,
+                "Nested lock detected! Cannot acquire lock on \"public\".\"foo\" while \"public\".\"bogus_table\" is locked."
+              )
 
               expect(locks_for_table(table_name, connection: alternate_connection)).to be_empty
             end