Thanks Adrian,
This all makes sense indeed
Jacques
From: "Jacopo Cappellato" <jacopo.cappell...@hotwaxmedia.com>
I agree that the overhaul will help to improve existing code (and fix bugs) and
also facilitate the migration to Groovy.
Jacopo
On Apr 5, 2012, at 12:27 PM, Adrian Crum wrote:
I don't think we will be able to eliminate mini-language entirely. As David has mentioned, and I agree - it is very convenient to
add a few lines of XML to a screen widget (or service definition in his example).
The purpose of the overhaul is to fix the numerous issues in mini-language that have been there for years. I believe those issues
are partially responsible for the waning interest in mini-language. My hope is that the overhaul will inspire a renewed interest
in the language. If that doesn't happen, then at least we will have a decent reference and implementation that can be spun off to
a separate project.
If a migration from mini-language to groovy were to take place, then I would recommend creating a utility to perform the
conversion. As I have mentioned previously, there is a mountain of mini-language code in OFBiz, and converting it all manually
will be impossible. A conversion utility will depend upon reliable mini-language source code (the XML files, not the Java
source). My initial tests with mini-language <set> element validation have shown that there are a lot of errors and nonsensical
code in the existing mini-language XML code base. A conversion utility will have a hard time making sense of it. Therefore, from
my perspective, regardless of whether mini-language stays or goes, some work will need to be done to clean up the existing
mini-language XML code base.
-Adrian
On 4/5/2012 10:54 AM, Jacques Le Roux wrote:
From a pragmatic point of view I'd not be against. The less syntaxes the better, and I know a lot of users are not using
minilang
for this reason. But it seems Adrian has already begin to work on the
Mini-language Overhaul...
Adrian should we not concentrate our efforts on reducing syntaxes in OFBiz? On the other hand I know replacing all minilang
code in OFBiz would be a long and "risky" task...
Jacques
From: "Jacopo Cappellato" <jacopo.cappell...@hotwaxmedia.com>
I completely agree that having *one* set on Minilang operations for all the actions (forms/screens/methods) is a good step
forward.
My only doubt is about the effort required for the migration: I see an opportunity to migrate all our applications code to
Groovy
instead; at that point all OFBiz code will be either Java or Groovy and
Freemarker.
Jacopo
On Apr 5, 2012, at 1:45 AM, Adrian Crum wrote:
If we can agree on the mini-language syntax and get a good implementation, then the next step would be to integrate it with
the
screen widgets. Personally, I have always wanted the screen widget <actions> element to behave the same way as the
mini-language
<simple-method> element. That concept can be extended further to have
<simple-method> elements in the screen widget files
(https://issues.apache.org/jira/browse/OFBIZ-4090).
-Adrian
On 4/4/2012 6:41 PM, Jacques Le Roux wrote:
Hi Adrian,
This looks like a great step forward. I really wonder though if we will still have many
possible syntaxes ("std minilang"
(should not vary with the place it's used), bsh, grooy, uel, etc.) or if it
will be more constrained
I guess you will follow David's suggestion on this?
What really bothers me with the simple-method stuff in OFBiz whenever I
use it is the inconsistency between the simple-method, screen actions,
form actions, etc, and the inconsistent handling of expressions and such
for field, from-field, value, etc attributes. Having everything use the
same XSD and having everything actually be a groovy expression (since it
is just transformed into a groovy script) made it much easier and less
frustrating to use.
I plenty agree with him. Moreover, I think we don't need many syntaxes, as long as the one provided supersedes all the
others.
On a long term, I can help to refactor current minilang code (which means also
screens and form actions of course).
Thanks
Jacques
From: "Adrian Crum" <adrian.c...@sandglass-software.com>
I think I have come up with a solution to fix the mini-language code:
mini-language auto-correction. If enabled, the element
models correct common mistakes and save the corrections to the original file.
This will still leave some warnings that will
need to be fixed manually.
-Adrian
On 4/3/2012 2:07 PM, Adrian Crum wrote:
I added parsing validation to the <set> element to see how it will work. The
validation can be enabled/disabled through a
property setting.
Just running the load-demo ant task generates hundreds of warnings - most of them are
caused by <set> attributes being used
incorrectly. On the positive side, a lot of nonsensical code is being revealed; on the negative side, the log is filled
with
warnings.
I'm not sure what I will do with this. If I commit the validation code, then we will have a lot of work to do to clean up
the
mini-language code.
-Adrian
On 3/8/2012 6:55 PM, Adrian Crum wrote:
Some more food for thought...
Looking through the Java code, I can see that there is no runtime validation
being performed. Granted, a decent XML editor
will warn you about required attributes and elements and such, but not everyone
uses that type of XML editor. Worse yet,
there is no way to know you've done something wrong - because mini-lang hides
the errors in verbose log statements. So, I
would like to add runtime validation. If the script is coded improperly, then
it should throw an exception.
Another change I would like to make is to remove default attribute values in the schema. From my perspective, defaults
should
be in the mini-language code. The wiki page has demonstrated to me how difficult it is to understand what's going on when
you
have to look through Java code, and then also look through the schema to see what values it is supplying. Plus, it makes
me
wonder how mini-language will behave when the server doesn't have access to the
schema.
Which brings up another point: Once the grammar has been cleaned up, we will
need a new schema. I think we need to start
giving our schemas version numbers so that XML editors and runtime XML
validation will work properly.
-Adrian
On 3/8/2012 6:19 PM, Jacopo Cappellato wrote:
On Mar 8, 2012, at 7:03 PM, Adrian Crum wrote:
B) instead of:
<fail-property resource="ErrorMessages" property="FooError" />
we could have
<fail-property property="ErrorMessages.FooError" />
Keep in mind that UEL would interpret FooError as an element of a Map called
ErrorMessages.
What you suggested can be done, but it will require more modifications to the
UEL integration - something I try to avoid
because it causes more problems than it solves. I recommend we keep the
resource attribute.
Np then, I was not even sure it was a good idea and if requires customizations
to uel then I agree it is not worth the
effort.
Thank you,
Jacopo
