Thanks Guillaume!

2013/12/2 Guillaume Nodet <[email protected]>

> I'll try to have a look at those today or tomorrow.
>
>
> 2013/12/2 Bengt Rodehav <[email protected]>
>
> > I've replaced FELIX-4332 with FELIX-4338 and FELIX-4339.
> >
> > I have attached a patch for FELIX-4338 and hope that someone can have a
> > look at it and possibly commit it.
> >
> > FELIX-4339 is trickier but I would appreciate a discussion about how this
> > should be handled.
> >
> > /Bengt
> >
> >
> > 2013/11/29 Bengt Rodehav <[email protected]>
> >
> > > I've tested more with the proposed change in order to stop FileInstall
> to
> > > incorrectly change the contents of the configuration file (problem b)
> > from
> > > my previous post). It seems to work fine. I would really like that to
> be
> > > fixed. Would you like me to create a patch atttached to the JIRA?
> > >
> > > Problem a) is probably not trivial to fix. I've experimented a lot and
> > > it's very hard for me to foresee how many escape characters I need in
> > > different circumstances. One real life example for me is how I
> configure
> > an
> > > integration service that uses a Camel route underneath. If I put the
> > > followiing contents in a test.cfg file:
> > >
> > > *mydir=C:/temp*
> > >
> > >
> >
> *timestampedfile=$\\\\{file:onlyname\\\\}-$\\\\{date:now:yyyyMMddHHmmssSSS\\\\}.$\\\\{file:ext\\\\}*
> > > *move=${mydir}/archive/$\\{date:now:yyyyMMdd\\}/${timestampedfile}*
> > > *moveFailed=${mydir}/failed/${timestampedfile}*
> > > *fromUri=file:${mydir}?move=${move}&moveFailed=${moveFailed}*
> > >
> > > And execute the following command:
> > >
> > >
> > > *config:list "(service.pid=test)"*
> > >
> > > I get the following output:
> > >
> > > *----------------------------------------------------------------*
> > > *Pid:            test*
> > > *BundleLocation: null*
> > > *Properties:*
> > > *   moveFailed =
> > >
> >
> C:/temp/failed/${file:onlyname}-${date:now:yyyyMMddHHmmssSSS}.${file:ext}*
> > > *   mydir = C:/temp*
> > > *   timestampedfile =
> > > $\{file:onlyname\}-$\{date:now:yyyyMMddHHmmssSSS\}.$\{file:ext\}*
> > > *   service.pid = test*
> > > *   fromUri =
> > > file:C:/temp?move=C:/temp/archive//-.&moveFailed=C:/temp/failed/-.*
> > > *   move =
> > >
> >
> C:/temp/archive/${date:now:yyyyMMdd}/${file:onlyname}-${date:now:yyyyMMddHHmmssSSS}.${file:ext}*
> > > *   felix.fileinstall.filename =
> > > file:/C:/dev/karaf/connect/common/etc/test.cfg*
> > >
> > > Thus, the variables "move" and "moveFailed" looks the way I want but
> the
> > > final variable "fromUri" is messed up because of an extra variable
> > > substitution.
> > >
> > > I haven't managed to come up with any number of backslashes that will
> > > produce the correct result for me.
> > >
> > > The only workaround I have right now is to not use variables at all. It
> > > does, however, make the configuration files extremely verbose and it's
> > easy
> > > to introduce errors that way.
> > >
> > > Presently, variable substitution is very unpredictable since it's being
> > > done in a recursive way. I would prefer doing it in an iterative manner
> > to
> > > make it predictable. E g "${a}" should always evaluate to the same
> value
> > no
> > > matter where in the configuration file it is referenced.
> > >
> > > /Bengt
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > > 2013/11/28 Bengt Rodehav <[email protected]>
> > >
> > >> I've investigated this a bit more. There are actually two different
> > >> problems:
> > >>
> > >> a) The number of escape characters I need depends on from where I
> > >> reference the variable. For every indirection I need to double the
> > number
> > >> of backslashes. This also means that all uses of a variable containing
> > >> escape characters must be used from the same level of indirection. A
> bit
> > >> complicated but it's due to the fact that all variables are evaluated
> > >> dynamically. This means that unescaping can occur several times.
> > >>
> > >> b) FileInstall incorrectly thinks that a configuration property is
> > >> changed and therefore overwrites the property with the evaluated
> value.
> > >>
> > >> I think I've found the reason (and possibly a solution) to b).
> > >>
> > >> In the ConfigInstaller.setConfig() method the properties are read
> from a
> > >> configuration file and propagated as a configuration. Here is an
> excerpt
> > >> from that method:
> > >>
> > >> *                final Properties p = new Properties();*
> > >> *                in.mark(1);*
> > >> *                boolean isXml = in.read() == '<';*
> > >> *                in.reset();*
> > >> *                if (isXml) {*
> > >> *                    p.loadFromXML(in);*
> > >> *                } else {*
> > >> *                    p.load(in);*
> > >> *                }*
> > >> *                InterpolationHelper.performSubstitution((Map) p,
> > >> context);*
> > >> *                ht.putAll(p);*
> > >>
> > >> Note that the file is read using Java's standard Properties class. The
> > >> unescaping is also done by that class. Then, at the end, the variable
> > >> substitution is done as a separate call.
> > >>
> > >> Then look at the ConfigInstaller.configurationEvent() method:
> > >>
> > >> *        if (configurationEvent.getType() ==
> > >> ConfigurationEvent.CM_UPDATED)*
> > >> *        {*
> > >> *            try*
> > >> *            {*
> > >> *                Configuration config =
> > >> getConfigurationAdmin().getConfiguration(*
> > >> *
> >  configurationEvent.getPid(),*
> > >> *
> > >> configurationEvent.getFactoryPid());*
> > >> *                Dictionary dict = config.getProperties();*
> > >> *                String fileName = (String) dict.get(
> > >> DirectoryWatcher.FILENAME );*
> > >> *                File file = fileName != null ?
> fromConfigKey(fileName)
> > :
> > >> null;*
> > >> *                if( file != null && file.isFile()   ) {*
> > >> *                    if( fileName.endsWith( ".cfg" ) )*
> > >> *                    {*
> > >> *                        org.apache.felix.utils.properties.Properties
> > >> props = new org.apache.felix.utils.properties.Properties( file,
> context
> > );*
> > >>
> > >> Note that now the configuration file is read using
> > >> org.apache.felix.utils.properties.Properties class. It turns out that
> > they
> > >> don't produce identical results. I haven't investigated exactly how
> they
> > >> differ but they do.
> > >>
> > >> A simple test:
> > >>
> > >> 1. Create a configuration file with the following content:
> > >>
> > >> a=$\\\\{var}
> > >> ab=${a}b
> > >> abc=${ab}c
> > >>
> > >> 2. Add the following line at the end:
> > >>
> > >> d=foo
> > >>
> > >> 3. FileInstall will now incorrectly change the contents of the
> > >> configuration file to:
> > >>
> > >>  a=$\\\\{var}
> > >> ab=${a}b
> > >> abc = ${var}bc
> > >> d=foo
> > >>
> > >> Now if I change the ConfigInstaller.setConfig() method to the
> following:
> > >>
> > >> *org.apache.felix.utils.properties.Properties p = new
> > >> org.apache.felix.utils.properties.Properties( f, context );*
> > >> *InterpolationHelper.performSubstitution((Map) p, context);*
> > >>
> > >> Then FileInstall will not incorrectly change the contents of the
> > >> configuration file.
> > >>
> > >> I propose to do this change in order to solve problem b) above. I
> > >> appreciate if you have any thoughts on this.
> > >>
> > >> I realize that problem a) is trickier due to the dynamic nature of
> > >> variable substitution. I haven't yet determined how I think the escape
> > >> characters should be handled but the current situation is not ideal.
> > >>
> > >> /Bengt
> > >>
> > >>
> > >>
> > >>
> > >> 2013/11/28 Bengt Rodehav <[email protected]>
> > >>
> > >>> JIRA created:
> > >>>
> > >>> https://issues.apache.org/jira/browse/FELIX-4332
> > >>>
> > >>> /Bengt
> > >>>
> > >>>
> > >>> 2013/11/28 Bengt Rodehav <[email protected]>
> > >>>
> > >>>> I've come up with easily reproducable errors using Karaf 2.3.3:
> > >>>>
> > >>>> - Install a fresh Karaf 2.3.3
> > >>>> - Add the following line to etc/custom.properties:
> > >>>>   felix.fileinstall.enableConfigSave = true
> > >>>>
> > >>>> Create a file etc/test.cfg with the following contents:
> > >>>>
> > >>>> a=$\\{var}
> > >>>> ab=${a}b
> > >>>> abc=${ab}c
> > >>>>
> > >>>> I expect this to be evaluated to:
> > >>>> a=$\{var}
> > >>>> ab=$\{var}b
> > >>>> abc=$\{var}bc
> > >>>>
> > >>>> But if I execute the Karaf command:
> > >>>>
> > >>>>   config:list "(service.pid=test)"
> > >>>>
> > >>>> I get:
> > >>>>
> > >>>> ----------------------------------------------------------------
> > >>>> Pid:            test
> > >>>> BundleLocation: null
> > >>>> Properties:
> > >>>>    service.pid = test
> > >>>>    a = ${var}
> > >>>>    abc = bc
> > >>>>    felix.fileinstall.filename =
> > >>>> file:/C:/dev/Karaf/apache-karaf-2.3.3/etc/test.cfg
> > >>>>    ab = b
> > >>>>
> > >>>> My interpretation of this is that the variable "a" has been
> correctly
> > >>>> evaluated. But, when evalutating the variable "ab" it seems that the
> > >>>> variable "a" is evaluated again despite the fact that it has already
> > been
> > >>>> evaluated. FileInstall now looks for the value of a variable called
> > "var"
> > >>>> which evalutes to an empty string because there is no such variable.
> > >>>>
> > >>>> The variable "abc" consequently evaluates to "bc" since the variable
> > >>>> "ab" has been evaluated to "b".
> > >>>>
> > >>>> To make it even worse, now change the first row in test.cfg to:
> > >>>>
> > >>>> a=$\\\\{var}
> > >>>>
> > >>>> We now get:
> > >>>>
> > >>>> ----------------------------------------------------------------
> > >>>> Pid:            test
> > >>>> BundleLocation: null
> > >>>> Properties:
> > >>>>    service.pid = test
> > >>>>    a = $\{var}
> > >>>>    abc = ${var}bc
> > >>>>    felix.fileinstall.filename =
> > >>>> file:/C:/dev/Karaf/apache-karaf-2.3.3/etc/test.cfg
> > >>>>    ab = ${var}b
> > >>>>
> > >>>> Thus we get the same phenomenom. The variable "a" is evaluated
> > >>>> differently if it is evaluated on its own or as part of another
> > expression.
> > >>>> But, due to having configured FileInstall to write back changes, the
> > >>>> contents of the test.cfg is now changed by FileInstall despite the
> > fact
> > >>>> that the configuration has not changed at all. The contents of
> > test.cfg is
> > >>>> now:
> > >>>>
> > >>>> a=$\\\\{var}
> > >>>> ab=${a}b
> > >>>> abc = ${var}bc
> > >>>>
> > >>>> The "abc" variable has been altered. FileInstall has incorrectly
> > >>>> determined that its value has changed.
> > >>>>
> > >>>> This is clearly a bug. I will create a JIRA.
> > >>>>
> > >>>> /Bengt
> > >>>>
> > >>>>
> > >>>>
> > >>>> 2013/11/26 Bengt Rodehav <[email protected]>
> > >>>>
> > >>>>> I'm using Apache Karaf 2.3.3 which comes with FileInstall 3.2.6. I
> > >>>>> have set the felix.fileinstall.enableConfigSave property to true in
> > order
> > >>>>> to have FileInstall write back configuration changes to the file.
> > Normally
> > >>>>> all configuration changes are done by editing the configuration
> file
> > but
> > >>>>> there is one property that I change programmatically using
> > ConfigAdmin (an
> > >>>>> "enable" property to start/stop my service). I am dependent on that
> > >>>>> property being persisted in the configuration file which is why I
> > set the
> > >>>>> enableConfigSave property to true.
> > >>>>>
> > >>>>> When configuring FileInstall to write back configuration changes to
> > >>>>> the configuration file, it is important that variables are not
> > substituted
> > >>>>> for the evaluated value. This normally works since FileInstall
> > evalutates
> > >>>>> the property in the configuration file and compares it with the
> > >>>>> configuration admin's value. If they are the same, the value in the
> > >>>>> configuration file is kept unchanged.
> > >>>>>
> > >>>>> However, when using the escape character this is broken. In my case
> > >>>>> I'm using Apache Camel underneath. When configuring routes via the
> > config
> > >>>>> admin, I sometimes need to set a value to
> > >>>>> "${expression-to-be-evaluated-by-camel}". I therefore escape the
> "{"
> > and
> > >>>>> "}" to stop FileInstall from trying to evaluate the expression.
> Like
> > this:
> > >>>>>
> > >>>>> $\\{expression-to-be-evaluated-by-camel\\}
> > >>>>>
> > >>>>> This also normally works but not when I have an indirection. E g
> when
> > >>>>> specifying the following:
> > >>>>>
> > >>>>> a=$\\{var}
> > >>>>> ab=${a}b
> > >>>>>
> > >>>>> FileInstall will change the configuration file to:
> > >>>>>
> > >>>>> a=$\\{var}
> > >>>>> ab = ${var}b
> > >>>>>
> > >>>>> Note that the variable "ab" has now been expanded and written back
> to
> > >>>>> the configuration file even if neither of the variables "a" and
> "ab"
> > have
> > >>>>> been changed.
> > >>>>>
> > >>>>> I think this is because FileInstall does the following:
> > >>>>>
> > >>>>> 1. Calculates the value of "a" to "$\{var}
> > >>>>> 2. Calculates the value of "b" to "${var}b
> > >>>>>
> > >>>>> Note that every evaluation will perform "unescaping". This means
> that
> > >>>>> an extra "unescaping" will be done for every indirection which
> fools
> > >>>>> FileInstall into thinking that the property has been changed.
> > >>>>>
> > >>>>> I'm not exactly sure how this should be fixed in FileInstall. One
> > idea
> > >>>>> is to never "unescape" already evaluated variables. Actually I
> think
> > this
> > >>>>> is probably what would fix this...
> > >>>>>
> > >>>>> Does anybody have any ideas about this? Should I create a JIRA?
> > >>>>>
> > >>>>> /Bengt
> > >>>>>
> > >>>>>
> > >>>>>
> > >>>>>
> > >>>>>
> > >>>>>
> > >>>>>
> > >>>>
> > >>>
> > >>
> > >
> >
>
>
>
> --
> -----------------------
> Guillaume Nodet
> ------------------------
> Red Hat, Open Source Integration
>
> Email: [email protected]
> Web: http://fusesource.com
> Blog: http://gnodet.blogspot.com/
>

Reply via email to