Improve error message in exceptions raised by ExtensionOption and OrderedExtensionOption

[Ryan J Ollos]

It was discussed in ​th:#10980 that we might improve the error message in the exceptions raised from ExtensionOption and OrderedExtensionOption when the Component is not active. For example:

ConfigurationError: Cannot find an implementation of the "IEmailSender" interface named "SmtpEmailSender". Please update the option announcer.email_sender in trac.ini.

→

ConfigurationError: Cannot find an implementation of the IEmailSender interface named SmtpEmailSender. Please check that the Component is enabled or update the option [announcer] email_sender in trac.ini.

[Ryan J Ollos]

Proposed change can be found in attachment:t11427.patch​. tt tags will be replaced with code tags on merge to trunk (#11094). The result is:

ExtensionOption:

Configuration Error

Cannot find an implementation of the ITicketGroupStatsProvider interface named DefaultTicketGroupStatsProvide. Please check that the Component is enabled or update the option [roadmap] stats_provider in trac.ini.

TracGuide — The Trac User and Administration Guide

---

OrderedExtensionOption:

Configuration Error

Cannot find implementation(s) of the IPermissionPolicy interface named MissingPermPolicyOne, MissingPermPolicyTwo. Please check that the Component is enabled or update the option [trac] permission_policies in trac.ini.

TracGuide — The Trac User and Administration Guide

[Ryan J Ollos]

I just noticed that the following are auto-linked:

ExtensionOption: → ExtensionOption:
**ExtensionOption** → ExtensionOption

but this one is not:

**ExtensionOption:** → ExtensionOption:

[Ryan J Ollos]

On second thought, the strings differ only by "… an implementation of …" / "… implementation(s) of …", so I will just make those the same and we will have one fewer string to translate.

[Ryan J Ollos]

I've modified the patch to add an entry for each implementation that is not found:

Configuration Error

Cannot find an implementation of the IPermissionPolicy interface named MissingPermPolicyOne. Please check that the Component is enabled or update the option [trac] permission_policies in trac.ini.

Cannot find an implementation of the IPermissionPolicy interface named MissingPermPolicyTwo. Please check that the Component is enabled or update the option [trac] permission_policies in trac.ini.

TracGuide — The Trac User and Administration Guide

The resulting diff of the pot file is:

trac/locale/messages.pot

@@ -454 +454 @@
 msgid "File '%(name)s' exists"
 msgstr ""
 
-#: trac/config.py:44
+#: trac/config.py:45
 msgid "Configuration Error"
 msgstr ""
 
-#: trac/config.py:48
+#: trac/config.py:49
 msgid "Look in the Trac log for more information."
 msgstr ""
 
-#: trac/config.py:273
+#: trac/config.py:274
 #, python-format
 msgid "Error reading '%(file)s', make sure it is readable."
 msgstr ""
 
-#: trac/config.py:430
+#: trac/config.py:431
 #, python-format
 msgid "[%(section)s] %(entry)s: expected integer, got %(value)s"
 msgstr ""
 
-#: trac/config.py:448
+#: trac/config.py:449
 #, python-format
 msgid "[%(section)s] %(entry)s: expected float, got %(value)s"
 msgstr ""
 
-#: trac/config.py:621
+#: trac/config.py:622
 msgid "Setting attribute is not allowed."
 msgstr ""
 
-#: trac/config.py:701
+#: trac/config.py:702
 #, python-format
 msgid "[%(section)s] %(entry)s: expected one of (%(choices)s), got %(value)s"
 msgstr ""
 
-#: trac/config.py:734
+#: trac/config.py:741 trac/config.py:778
 #, python-format
 msgid ""
-"Cannot find an implementation of the \"%(interface)s\" interface named "
-"\"%(implementation)s\".  Please update the option %(section)s.%(name)s in"
-" trac.ini."
+"Cannot find an implementation of the %(interface)s interface named "
+"%(implementation)s. Please check that the Component is enabled or update "
+"the option %(option)s in trac.ini."
 msgstr ""
 
-#: trac/config.py:772
-#, python-format
-msgid ""
-"Cannot find implementation(s) of the \"%(interface)s\" interface named "
-"\"%(implementation)s\".  Please update the option %(section)s.%(name)s in"
-" trac.ini."
-msgstr ""
-
-#: trac/config.py:813 trac/config.py:826
+#: trac/config.py:822 trac/config.py:835
 #, python-format
 msgid "Option '%(option)s' doesn't exist in section '%(section)s'"
 msgstr ""

[Ryan J Ollos]

Didn't mean to close this yet. I'm still just posting changes for review.

[Jun Omae]

Looks good. But I like to show multiple component names in a error message, not each message. See [a54790de/jomae.git].

---

Configuration Error

Cannot find implementation(s) of the IPermissionPolicy interface named AlphaPolicy, BetaPolicy, ThetaPolicy. Please check that the Component is enabled or update the option [trac] permission_policies in trac.ini.

TracGuide — The Trac User and Administration Guide

[Ryan J Ollos]

Replying to jomae:

Looks good. But I like to show multiple component names in a error message, not each message.

Would you suggest using the same error message for ExtensionOption as well, or having a slightly different message, as shown in comment:2? I tend to think it will be strange to use the same error message and suggest that implementation(s) could exist for an ExtensionOption.

[Jun Omae]

Replying to rjollos:

Would you suggest using the same error message for ExtensionOption as well, or having a slightly different message, as shown in comment:2?

The message for OrderedExtensionOption in comment:2 is the same.

However, that generates a tt element for each component name, not one tt element.

<tt>AlphaPolicy, BetaPolicy, ThetaPolicy</tt>
→
<tt>AlphaPolicy</tt>, <tt>BetaPolicy</tt>, <tt>ThetaPolicy</tt>

I tend to think it will be strange to use the same error message and suggest that implementation(s) could exist for an ExtensionOption.

I understand your intention. But, if more than one missing components are in trac.ini, I confused and scared similar messages which are repeated, e.g. Cannot find … in trac.ini. Cannot find … in trac.ini. in comment:5.

[Ryan J Ollos]

Committed to 1.0-stable in [12430] and merged to trunk in [12431]. Replaced tt tags with code tags on trunk in [12432].

[Ryan J Ollos]

Replying to Ryan J Ollos:

I just noticed that the following are auto-linked:

ExtensionOption: → ExtensionOption:
**ExtensionOption** → ExtensionOption

but this one is not:

**ExtensionOption:** → ExtensionOption:

Reported in #12733.