26 May
2012
26 May
'12
8:17 p.m.
Hi Sergiu,
On May 26, 2012, at 7:16 PM, Sergiu Dumitriu wrote:
We already have a standard for xwiki configuration and it's called
xwiki-configuration, that's why ;)
Having 10 places to configure xwiki is not exactly the simplest either…
OK then, so you're proposing to also move components.txt, struts-config.xml,
fop-config.xml, xhtml2fo.xsl, log4j.properties and logback.xml into xwiki.properties, so
that any library we're using should be configured in the same place, right?
When everyone that knows how to configure these generic libraries in any other project,
isn't it going to be a surprise when logback.xml suddently doesn't work? Searching
for "how do I enable debug logging in log4j" isn't going to lead to
"simple, edit xwiki.properties and bla bla", but to "edit logback.xml and
bla bla". Similarly, when searching for "how do I increase the pool size for
hibernate" is going to lead to "use this XML snippet in hibernate.cfg.xml".
Discovering that hibernate.cfg.xml doesn't exist but those setting must be placed in
xwiki.properties, and how that XML snippet translates into properties is going to take
some time... One thing I learned? Nobody reads documentation unless they really have to,
and they don't always read the official documentation that they should read, but
instead end up on forums and blog posts.
Again i'm not pushing too much for this. But what I'd like is to have all those
files located in the same configuration data directory. I had assumed we wanted to have
the environment.permanentDirectory be that directory but Denis suggested to have 2
different directories which is kind of ok (I need to think more about this - BTW Denis
commons-configuration allows modifying the configuration files so we also have the ability
- should we want it - to write into configuration files).
On 05/25/2012 12:56 PM, Vincent Massol wrote:
Maybe you're not aware of the capability of commons-configuration; you can have the
config data in any format, including XML and you can have a Composite Configuration which
loads several config data in different formats (properties, xml, database, etc).
I haven't checked recently but it was supporting all that when I introduced the
xwiki-configuration module so I guess this is still the case.
On May 25, 2012, at 3:38 PM, Sergiu Dumitriu wrote:
This isn't about how much or little commons-configuration can do, but about the fact
that hibernate configuration is done in its XML configuration file in any other project.
and changing that, although it would be better for us, it's going to make it harder
for sysadmins to properly configure their connection when only we know where and how the
configuration works. On 05/25/2012 05:21 AM, Denis Gervalle wrote:
Guys you really need to read the link I gave you about commons-configuration ;)
commons-configuration supports nested properties whether they are stored in xml, in
properties files or elsewhere. On Thu, May 24, 2012 at 7:23 PM, Vincent
Massol<vincent(a)massol.net> wrote:
>
> On May 24, 2012, at 9:09 AM, Denis Gervalle wrote:
>
>> On Tue, May 22, 2012 at 4:03 PM, Vincent Massol<vincent(a)massol.net>
> wrote:
>>
>>>
>>> On May 22, 2012, at 3:51 PM, Sergiu Dumitriu wrote:
>>>
>>>> On 05/22/2012 08:59 AM, Vincent Massol wrote:
>>>>>
>>>>> On May 22, 2012, at 2:49 PM, Vincent Massol wrote:
>>>>>
>>>>>> Hi devs,
>>>>>>
>>>>>> I need to be able to configuration the location of the HSQLDB
>>> database/ directory in our installer when executing on windows7
> (because on
>>> windows7 you cannot write to the ProgramFiles directory).
>>>>>>
>>>>>> I'm proposing to add variable substitution so that we can
configure
>>> connectio.url for HSQLDB to point to the environment.permanentDirectory
>>> location.
>>>>>>
>>>>>> We would have:
>>>>>> <property
>>>
>
name="connection.url">jdbc:hsqldb:file:${environment.permanentDirectory)/database/xwiki_db;shutdown=true</property>
>>>>>>
>>>>>> Technical details:
>>>>>> * I'll modify DBCPConnectionProvider. More specifically this
part:
>>>>>>
>>>>>> String jdbcUrl = System.getProperty(Environment.URL);
>>>>>> if (jdbcUrl == null) {
>>>>>> jdbcUrl = props.getProperty(Environment.URL);
>>>>>> }
>>>>>> dbcpProperties.put("url", jdbcUrl);
>>>>>>
>>>>>> * And look for ${…} , extract the variable name and use the
>>> XWikiPropertiesConfigurationSource to get the value for that variable
> name,
>>> as a String.
>>>>>>
>>>>>> WDYT?
>>>>>
>>>>> Note that another solution to this is to move all Hibernate
>>> configuration data to xwiki.properties… Since we allow property
> referencing
>>> in our xwiki.properties file it would solve my need too.
>>>>>
>>>>> It's a lot more more work though (unless we support both,
looking
> first
>>> in xwiki.properties for hibernate properties and fallbacking to older
>>> hibernate.cfg.xml if not found, in which case it's a little less work
> but
>>> still substantial). I'm still unsure I'm prepared to work on this
now…
> :)
>>>>>
>>>>> WDYT?
>>>>
>>>> I don't like this that much, since there's a lot more that can
be
>>> configured in the xml file, and the .properties is already getting very
> big.
>>>
>>> If we really think that the size of the file is important (which I'm not
>>> sure about) then we have the option of having as many configuration
> files
>>> as possible by using a CompositeConfiguration.
>>>
>>
>> I agree with Sergiu, but this is not a question of file size. Duplicating
>> the work done for hibernate configuration is not good, we would both
> limit
>> the flexibility since duplicating the whole possibilities would be hard,
>
> No it wouldn't ;-)
>
> We would automatically take all props starting with storage.hibernate.*
> and pass them.
>
hibernate.cfg.xml is not just a simple list of properties. Are we talking
about the same thing ?
My point exactly. Here's the structure of the XML file:
view-source:http://www.jboss.org/dtd/hibernate/hibernate-configuration-3.0.…
It's not just a flat session-factory with a list of property and mapping tags. We
don't know how more advanced installations use this file, and maybe we'll learn
more about using Hibernate the right way, and we'll need to add other elements:
listeners, security, caches… >> and
also confuse those who already knows the syntax of such file. So, I
>> like more the variable substitution proposal. With that one, we could
>> provide a simplified configuration in our ConfigurationSource, while
>> keeping the possibility of configuring the XML file directly. This is the
>> best of both worlds IMO.
>
> As I replied to sergiu there's also a 3rd solution: using a different file
> but with commons configuration.
>
Not sure to understand what you means. All I say is that the
hibernate.cfg.xml is a well-known configuration file, and that it is nice
to be able to use it directly. This is why I prefer variable substitution
in that file, taking any properties from our environment.
Exactly. Most of our users don't have to do much to configure their wiki for a
different database, but if they do need to do some tweaking, all the search results will
point to XML snippets, not to xwiki.properties. We try to stick to standards, why create
our own here? Sure, our xwiki.properties file is much simpler to
understand, but that's not what any other human being on earth is expecting.
All that I care is that XWiki users need to configuration hibernate configuration data.
Whether it belongs to XWiki or not is a philosophical topic that doesn't interest me
that much ATM ;)
Sergiu I don't disagree with what you're saying. Again what's important to me
is first and foremost to group configuration files together (same for permanent data we
output).
Having them under commons-configuration is just a nice to have since it allows to benefit
from a lot of features (including ability to share variables AFAIU). We can check later
and more precisely if we can have the best of both worlds (don't have much time for
that anyway).
BTW I don't consider components.xml to be a configuration file. It's not
modifiable by the user.
Thanks
-Vincent
Anyway to summarize:
1) I'm not pushing too strongly for merging configuration in our file
2) However it could be nice to be able to use xwiki-configuration for all configuration
data since this allows to access the full config from anywhere in our code using
ConfigurationSource and have links between them by using variables (just to cite 2
features).
Hibernate is not part of XWiki, it's a bridge between XWiki and the database. > AFAICS 2) is supported by commons-configuration
and of course it would require some tweaks to our configuration API since it currently
offers a minimal API and is far from offering what is supported by apache commons
configuration.
>
> For the time being I'll go with adding code to support variable substitution and
if I get the time I'll investigate a bit more to see how we could use apache commons
configuration while keeping separate config files (including keeping the native format).
>
> Thanks
> -Vincent
>
>>>> Thanks
>>>> Vincent
>>>>
>>>>>> The important point here is not so much to have hibernate config
in the
>>>>>> same file but rather to have it under our ConfigurationSource
mechanism.
>>>>>>
>>>>>> Thanks
>>>>>> -Vincent