More explicit error message when DSN alias is not found (#1198)

* add a specific error message when DSN with provided alias is not found

* update changelog & authors file

changelog.rst

@@ -17,6 +17,7 @@ Bug fixes:
 * Minor typo fixes in `pgclirc`. (Thanks: `anthonydb`_)
 * Fix for list index out of range when executing commands from a file (#1193). (Thanks: `Irina Truong`_)
 * Move from `humanize` to `pendulum` for displaying query durations (#1015)
+* More explicit error message when connecting using DSN alias and it is not found.
 
 3.0.0
 =====

pgcli/main.py

@@ -1284,7 +1284,15 @@ def cli(
         try:
             cfg = load_config(pgclirc, config_full_path)
             dsn_config = cfg["alias_dsn"][dsn]
-        except:
+        except KeyError:
+            click.secho(
+                f"Could not find a DSN with alias {dsn}. "
+                'Please check the "[alias_dsn]" section in pgclirc.',
+                err=True,
+                fg="red",
+            )
+            exit(1)
+        except Exception:
             click.secho(
                 "Invalid DSNs found in the config file. "
                 'Please check the "[alias_dsn]" section in pgclirc.',