| Re: [p2-dev] Product publishing and product update |
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Hello again, I am continuing with some experiments along the directions that
Jeff gave me. I encountered several problems for which I cannot find an
explanation. For example, I tried to update the product after incrementing its
version in the repository. The update failed again because it lists among its requirements
a tooling configuration unit which is a singleton. It looks quite simple: <unit id='tooling<product name>.configuration'
version='<product version>'> <provides size='1'> <provided
namespace='org.eclipse.equinox.p2.iu' name='tooling<product name>.configuration'
version='<product version>'/> </provides> <touchpoint id='null' version='0.0.0'/> </unit> Note that this is generated by the product publisher and cannot
be avoided. I don’t have any idea what the purpose of such a basic unit
could be but being a singleton and a requirement of the product, it stops the update
of the whole product because there is already an IU installed with the same
name on the system (actual message from p2 director says “Only one of the
following can be installed at once”, concerning this IU). Can anybody tell me why is this configuration unit created at
all on publishing ? In general, I am very surprised to see how many problems I encounter
to implement a “simple” product update given the fact that p2
supports updates of features and bundles out of the box. So far, the most
direct approaches I tried failed completely: -
If I try to update, preserving the same product version (as it
is fixed in the .product descriptor), it fails because of conflicting versions
of the requirements. -
If I try to update with an increased version of the product,
then the singleton configuration unit stops me. So it seems that my initial concept how the product update
should be done is wrong. But then how new versions of products are supposed to
be shipped to customers to be consumed immediately by p2 ? How are the customers
supposed to perform updates of the whole product (not by individual bundles and
features) ? Best regards, Shenny From:
p2-dev-bounces@xxxxxxxxxxx [mailto:p2-dev-bounces@xxxxxxxxxxx] On Behalf Of Jeff
McAffer There are a couple sides to
this. One is that if you have Product X v 1.2.3.20100923, that should
mean something. If you allow ranges as described, then two users installing
X 1.2.3.20100923 may not get the same actual software installed. Variation
is introduced for example, if user 1 has access to a different set of repos
than user 2 or there is a network error for user 1 but not user 2 or the single
repo changed between when user 1 and user 2 did their install. Of course, these behaviours *could* also be exactly what you
want but certainly some folks free at this non-determinism as a support
nightmare. Anyway, looking at features, they allow for things to be
*included* or *required*. Included things have exact version ranges while
required things have, generally, wider ranges. Traditionally the notion was
that on install, the things *included* by the feature were installed whereas
the things *required* merely had to be there. Early update manager didn't even help
you find/get/install the required things. That was goofy so we provided a
means for users to say "yeah, get the required stuff also". Now
with p2 we do this automatically without involving the user. So much for
context... It would be reasonable to allow ranges on product content
but it would also force the product designer to be very aware of the
consequences pointed out at the beginning of this message. I honestly don't
know what people would do naturally or what guidance we could/should give them (e.g.,
what's the default?). Back to your original topic, there is also the possibility
of producing new versions of your product that identify the new versions of the
components. Product production and distribution in p2 is very light weight and
users would see this as incoming new versions of the product (that they know
about) vs changes to random components (that they may well not even know
exist). What would you say as the user of some banking product if told
that there was a new version of EMF? "WFT?!" Scenarios vary. If that does not work for you, you can
insulate your product by making it consist of one feature. In that feature,
*require* everything that you want to be updatable, include the stuff you want
to be fixed (or put this stuff directly in the product). The product will
be bound to the one version of your container feature and the container feature
can use ranges. Beware the problems outlined above with non-determinism.
Note that you can also usethe p2.inf file to do this. Andew Niefer
did a couple blog posts on this a while ago Good luck Jeff On 2010-09-23, at 12:13 PM, Yousouf, Shenol wrote:
Hi
all, I
noticed that product publishing always sets requirements for a fixed version of the contained
bundles/features, i.e. the defined range has its lower and upper boundaries
equal like this: <required namespace="org.eclipse.equinox.p2.iu" name="TestBundle"range="[1.0.0.201009171510,1.0.0.201009171510]"
/> while
I need something like this: <required namespace="org.eclipse.equinox.p2.iu" name="TestBundle"range="[1.0.0.201009171510,2.0.0)"
/> or
even this: <required namespace="org.eclipse.equinox.p2.iu" name="TestBundle" range="1.0.0.201009171510"
/> (which means “any version > 1.0.0.201009171510”) The
.product file format does not support a way to specify a range for its
components, only an attribute for a fixed version. The product publisher also
has no notion how to generate version ranges – it simply sets the range
boundaries equal to the component version (see method AbstractPublisherAction.createIURequirements() for reference). So far, I cannot find
a way how to workaround this issue and in my opinion it as a limitation of the
product definition concept. Why
is this so important ? The use case is like this: I
am developing a product consisting of several components which is getting
published on an update site on a regular basis. The components receive frequent
updates in the p2 repository and their versions are incremented which is
reflected in the requirements of the published product. However, once I install
this product, I cannot apply updates to the system any more. The updates are
refused because version ranges of the requirements for the installed and the
updated products do not intersect which seems to make them incompatible. This
wouldn’t be the case if it was possible to define open ranges in the
product file. For example, the installed product would require a specific
component in version range [1.0.0, 2.0.0) while its new version would require
it in the range [1.1.0, 2.0.0). This would allow the update to pass because
obviously range [1.1.0, 2.0.0) is compatible with (falls into) range [1.0.0,
2.0.0). The way they are generated now is [1.0.0, 1.0.0] for the old product
and [1.1.0,1.1.0] for the new one. Since these two ranges do not intersect, the
update is not possible. In
short, I have two issues and hope to receive some advice from you how to
address them:
Best
regards, Shenny _______________________________________________ |