Re: JSON Pointer/Patch issue with /-

[Romain Manni-Bucau]

Let say it enables more control whereas this kind of toggle system
properties can be random when apps don't need the same (once again it is
functional and not about perf there).
Feel free to take back my PR, was just sharing the idea with code to try to
fix it together faster.

Romain Manni-Bucau
@rmannibucau  |  Blog
 | Old Blog
 | Github  |
LinkedIn  | Book



Le mer. 2 déc. 2020 à 15:30, Jean-Louis MONTEIRO  a
écrit :

> Hey Romain,
>
> Your email was clear on how to do it. But thanks for creating the PR.
> To be honest, I don't really care if you prefer this way. Essentially,
> instead of adding a property into a file, I'll now add a Maven dependency
> into my pom file.
>
> Does not change much.
> If on the other hand, it makes OSGi deployments easier, I'm fine with it. I
> just need some updates in your PR if I may.
>
> Le mer. 2 déc. 2020 à 13:13, Romain Manni-Bucau  a
> écrit :
>
> > Send a PR with the "SPI" option which enables to have this toggle *at
> will*
> > and drop it when not desired anymore without any config.
> > Hope it illustrates better than words one toggle option which
> > wouldnt depend on the env.
> >
> > Romain Manni-Bucau
> > @rmannibucau  |  Blog
> >  | Old Blog
> >  | Github <
> > https://github.com/rmannibucau> |
> > LinkedIn  | Book
> > <
> >
> https://www.packtpub.com/application-development/java-ee-8-high-performance
> > >
> >
> >
> > Le mer. 2 déc. 2020 à 11:49, Jean-Louis MONTEIRO  a
> > écrit :
> >
> > > I understand it's a nice feature and the RFC does not address it.
> > > What I'm not happy with is that adding this feature breaks what's
> > actually
> > > in the spec.
> > >
> > > I would prefer us to implement this feature without breaking standard
> > > features.
> > > I'll push a proposal for now and we can improve.
> > >
> > >
> > >
> > >
> > > Le mar. 1 déc. 2020 à 15:13, Romain Manni-Bucau  >
> > a
> > > écrit :
> > >
> > > > Le mar. 1 déc. 2020 à 14:40, Jonathan Gallimore <
> > > > jonathan.gallim...@gmail.com> a écrit :
> > > >
> > > > > I'll address a few points inline below, but at a high level, what
> are
> > > we
> > > > > looking to achieve from a spec/tck challenge?
> > > > >
> > > > > I can see a case for some clarification and updates to the Javadoc.
> > > > >
> > > > > The assertions that /- will return an error (as that references an
> > > index
> > > > to
> > > > > append to after the *end* of an array - i.e. array.length) are
> tested
> > > in
> > > > > the TCK, and other implementations must be passing that TCK. It's
> > hard
> > > to
> > > > > see a spec change happening, as there is no spec document beyond
> the
> > > RFCs
> > > > > that I can find. A TCK change that would enable Johnzon to pass,
> and
> > > > > require other currently passing implementations to make a change
> > seems
> > > > > unlikely. Jakarta EE 8's TCK has been around a while and has
> > > > > implementations that pass. The Jakarta EE 9 TCK is basically "done"
> > and
> > > > is
> > > > > essentially the same as EE8, bar the namespace change. I guess
> > adding a
> > > > > test exclude is possible, but serves to make this more vague and
> > vendor
> > > > > dependent (and non-portable) which feels like it defeats the
> purpose
> > -
> > > > > surely having it better defined and tested is the way to go.
> > > > >
> > > >
> > > > Well, here the fact is that it does not impact other vendors since it
> > is
> > > a
> > > > johnzon vendor specific feature we put in a shadow of the
> > (javax/jakarta)
> > > > spec handling in a custom fashion an error case.
> > > > Typically the case where we can exclude the TCK since it is
> irrelevant
> > > for
> > > > our impl but I understand also it is not perfect.
> > > >
> > > >
> > > > >
> > > > > I appreciate that this introduces a backwards incompatible change,
> > and
> > > > that
> > > > > there may be other consumers of the library that would have an
> issue
> > if
> > > > > this just changed. This seems like a fairly straightforward case
> that
> > > > could
> > > > > be easily and quickly solved with a feature switch, and passing the
> > TCK
> > > > is
> > > > > a worthwhile goal, both for Johnzon and TomEE. I suspect the TCK
> > > > challenge
> > > > > will take a bit of time, and we'll likely end up back at the
> feature
> > > > switch
> > > > > anyway.
> > > > >
> > > >
> > > > Issue is we dont have a Json.createPointerFactory(mapWithToggle) so
> it
> > > is a
> > > > global flag which means it breaks some deployments anyway - at least
> at
> > > > tomee level - when > 1 app is deployed (or >= 1 app + 1 extension).
> > > >
> > > >
> > > > >

Re: JSON Pointer/Patch issue with /-

[Jean-Louis MONTEIRO]

Hey Romain,

Your email was clear on how to do it. But thanks for creating the PR.
To be honest, I don't really care if you prefer this way. Essentially,
instead of adding a property into a file, I'll now add a Maven dependency
into my pom file.

Does not change much.
If on the other hand, it makes OSGi deployments easier, I'm fine with it. I
just need some updates in your PR if I may.

Le mer. 2 déc. 2020 à 13:13, Romain Manni-Bucau  a
écrit :

> Send a PR with the "SPI" option which enables to have this toggle *at will*
> and drop it when not desired anymore without any config.
> Hope it illustrates better than words one toggle option which
> wouldnt depend on the env.
>
> Romain Manni-Bucau
> @rmannibucau  |  Blog
>  | Old Blog
>  | Github <
> https://github.com/rmannibucau> |
> LinkedIn  | Book
> <
> https://www.packtpub.com/application-development/java-ee-8-high-performance
> >
>
>
> Le mer. 2 déc. 2020 à 11:49, Jean-Louis MONTEIRO  a
> écrit :
>
> > I understand it's a nice feature and the RFC does not address it.
> > What I'm not happy with is that adding this feature breaks what's
> actually
> > in the spec.
> >
> > I would prefer us to implement this feature without breaking standard
> > features.
> > I'll push a proposal for now and we can improve.
> >
> >
> >
> >
> > Le mar. 1 déc. 2020 à 15:13, Romain Manni-Bucau 
> a
> > écrit :
> >
> > > Le mar. 1 déc. 2020 à 14:40, Jonathan Gallimore <
> > > jonathan.gallim...@gmail.com> a écrit :
> > >
> > > > I'll address a few points inline below, but at a high level, what are
> > we
> > > > looking to achieve from a spec/tck challenge?
> > > >
> > > > I can see a case for some clarification and updates to the Javadoc.
> > > >
> > > > The assertions that /- will return an error (as that references an
> > index
> > > to
> > > > append to after the *end* of an array - i.e. array.length) are tested
> > in
> > > > the TCK, and other implementations must be passing that TCK. It's
> hard
> > to
> > > > see a spec change happening, as there is no spec document beyond the
> > RFCs
> > > > that I can find. A TCK change that would enable Johnzon to pass, and
> > > > require other currently passing implementations to make a change
> seems
> > > > unlikely. Jakarta EE 8's TCK has been around a while and has
> > > > implementations that pass. The Jakarta EE 9 TCK is basically "done"
> and
> > > is
> > > > essentially the same as EE8, bar the namespace change. I guess
> adding a
> > > > test exclude is possible, but serves to make this more vague and
> vendor
> > > > dependent (and non-portable) which feels like it defeats the purpose
> -
> > > > surely having it better defined and tested is the way to go.
> > > >
> > >
> > > Well, here the fact is that it does not impact other vendors since it
> is
> > a
> > > johnzon vendor specific feature we put in a shadow of the
> (javax/jakarta)
> > > spec handling in a custom fashion an error case.
> > > Typically the case where we can exclude the TCK since it is irrelevant
> > for
> > > our impl but I understand also it is not perfect.
> > >
> > >
> > > >
> > > > I appreciate that this introduces a backwards incompatible change,
> and
> > > that
> > > > there may be other consumers of the library that would have an issue
> if
> > > > this just changed. This seems like a fairly straightforward case that
> > > could
> > > > be easily and quickly solved with a feature switch, and passing the
> TCK
> > > is
> > > > a worthwhile goal, both for Johnzon and TomEE. I suspect the TCK
> > > challenge
> > > > will take a bit of time, and we'll likely end up back at the feature
> > > switch
> > > > anyway.
> > > >
> > >
> > > Issue is we dont have a Json.createPointerFactory(mapWithToggle) so it
> > is a
> > > global flag which means it breaks some deployments anyway - at least at
> > > tomee level - when > 1 app is deployed (or >= 1 app + 1 extension).
> > >
> > >
> > > >
> > > > On Fri, Nov 27, 2020 at 10:44 AM Romain Manni-Bucau <
> > > rmannibu...@gmail.com
> > > > >
> > > > wrote:
> > > >
> > > > > Hi JL,
> > > > >
> > > > > As discussed together - but sharing for others - we must take into
> > > > account
> > > > > some points:
> > > > >
> > > > > 1. reading both spec, JSON-Patch enables to handle /- as your first
> > did
> > > > (ie
> > > > > consider it is last element). JSON-Patch uses JSON-Pointer but
> > nowhere
> > > it
> > > > > is written it behaves as JSON-Pointer in all cases and it is
> > typically
> > > > > "integration" definition which can extend an underlying spec
> > (otherwise
> > > > > most of EE wouldn't be right? ;))
> > > > >
> > > >
> > > > I think the idea is that it references a non-existent element,
> *after*
> > > the
> > > > last element in an array. So if you have an array [0, 1, 2, 3, 4],
> then
> > > > "/-" would reference element _5_ (assuming you start your 

Re: JSON Pointer/Patch issue with /-

[Romain Manni-Bucau]

Send a PR with the "SPI" option which enables to have this toggle *at will*
and drop it when not desired anymore without any config.
Hope it illustrates better than words one toggle option which
wouldnt depend on the env.

Romain Manni-Bucau
@rmannibucau  |  Blog
 | Old Blog
 | Github  |
LinkedIn  | Book



Le mer. 2 déc. 2020 à 11:49, Jean-Louis MONTEIRO  a
écrit :

> I understand it's a nice feature and the RFC does not address it.
> What I'm not happy with is that adding this feature breaks what's actually
> in the spec.
>
> I would prefer us to implement this feature without breaking standard
> features.
> I'll push a proposal for now and we can improve.
>
>
>
>
> Le mar. 1 déc. 2020 à 15:13, Romain Manni-Bucau  a
> écrit :
>
> > Le mar. 1 déc. 2020 à 14:40, Jonathan Gallimore <
> > jonathan.gallim...@gmail.com> a écrit :
> >
> > > I'll address a few points inline below, but at a high level, what are
> we
> > > looking to achieve from a spec/tck challenge?
> > >
> > > I can see a case for some clarification and updates to the Javadoc.
> > >
> > > The assertions that /- will return an error (as that references an
> index
> > to
> > > append to after the *end* of an array - i.e. array.length) are tested
> in
> > > the TCK, and other implementations must be passing that TCK. It's hard
> to
> > > see a spec change happening, as there is no spec document beyond the
> RFCs
> > > that I can find. A TCK change that would enable Johnzon to pass, and
> > > require other currently passing implementations to make a change seems
> > > unlikely. Jakarta EE 8's TCK has been around a while and has
> > > implementations that pass. The Jakarta EE 9 TCK is basically "done" and
> > is
> > > essentially the same as EE8, bar the namespace change. I guess adding a
> > > test exclude is possible, but serves to make this more vague and vendor
> > > dependent (and non-portable) which feels like it defeats the purpose -
> > > surely having it better defined and tested is the way to go.
> > >
> >
> > Well, here the fact is that it does not impact other vendors since it is
> a
> > johnzon vendor specific feature we put in a shadow of the (javax/jakarta)
> > spec handling in a custom fashion an error case.
> > Typically the case where we can exclude the TCK since it is irrelevant
> for
> > our impl but I understand also it is not perfect.
> >
> >
> > >
> > > I appreciate that this introduces a backwards incompatible change, and
> > that
> > > there may be other consumers of the library that would have an issue if
> > > this just changed. This seems like a fairly straightforward case that
> > could
> > > be easily and quickly solved with a feature switch, and passing the TCK
> > is
> > > a worthwhile goal, both for Johnzon and TomEE. I suspect the TCK
> > challenge
> > > will take a bit of time, and we'll likely end up back at the feature
> > switch
> > > anyway.
> > >
> >
> > Issue is we dont have a Json.createPointerFactory(mapWithToggle) so it
> is a
> > global flag which means it breaks some deployments anyway - at least at
> > tomee level - when > 1 app is deployed (or >= 1 app + 1 extension).
> >
> >
> > >
> > > On Fri, Nov 27, 2020 at 10:44 AM Romain Manni-Bucau <
> > rmannibu...@gmail.com
> > > >
> > > wrote:
> > >
> > > > Hi JL,
> > > >
> > > > As discussed together - but sharing for others - we must take into
> > > account
> > > > some points:
> > > >
> > > > 1. reading both spec, JSON-Patch enables to handle /- as your first
> did
> > > (ie
> > > > consider it is last element). JSON-Patch uses JSON-Pointer but
> nowhere
> > it
> > > > is written it behaves as JSON-Pointer in all cases and it is
> typically
> > > > "integration" definition which can extend an underlying spec
> (otherwise
> > > > most of EE wouldn't be right? ;))
> > > >
> > >
> > > I think the idea is that it references a non-existent element, *after*
> > the
> > > last element in an array. So if you have an array [0, 1, 2, 3, 4], then
> > > "/-" would reference element _5_ (assuming you start your numbering at
> > 0),
> > > and not the last element in the array (index 4).
> > >
> >
> > This is the jsonpointer spec right,  but JSONPatch never requires to not
> > handle the case as we do, it is just not written (and why we used it
> also).
> > Issue on jsonpointer side being we can't have another character which
> means
> > "last element".
> >
> >
> > >
> > >
> > > > 2. On johnzon point of view we can't break this feature which was
> > > requested
> > > > by user and transitive users (ie user of products built with johnzon)
> > > > without at least a clear migration path so if we want to break we
> > should
> > > do
> > > > a 1.3 (dont think we need a 1.2 maintenance branch, we can do it
> > lazily),
> > > > 

Re: JSON Pointer/Patch issue with /-

[Jean-Louis MONTEIRO]

I understand it's a nice feature and the RFC does not address it.
What I'm not happy with is that adding this feature breaks what's actually
in the spec.

I would prefer us to implement this feature without breaking standard
features.
I'll push a proposal for now and we can improve.




Le mar. 1 déc. 2020 à 15:13, Romain Manni-Bucau  a
écrit :

> Le mar. 1 déc. 2020 à 14:40, Jonathan Gallimore <
> jonathan.gallim...@gmail.com> a écrit :
>
> > I'll address a few points inline below, but at a high level, what are we
> > looking to achieve from a spec/tck challenge?
> >
> > I can see a case for some clarification and updates to the Javadoc.
> >
> > The assertions that /- will return an error (as that references an index
> to
> > append to after the *end* of an array - i.e. array.length) are tested in
> > the TCK, and other implementations must be passing that TCK. It's hard to
> > see a spec change happening, as there is no spec document beyond the RFCs
> > that I can find. A TCK change that would enable Johnzon to pass, and
> > require other currently passing implementations to make a change seems
> > unlikely. Jakarta EE 8's TCK has been around a while and has
> > implementations that pass. The Jakarta EE 9 TCK is basically "done" and
> is
> > essentially the same as EE8, bar the namespace change. I guess adding a
> > test exclude is possible, but serves to make this more vague and vendor
> > dependent (and non-portable) which feels like it defeats the purpose -
> > surely having it better defined and tested is the way to go.
> >
>
> Well, here the fact is that it does not impact other vendors since it is a
> johnzon vendor specific feature we put in a shadow of the (javax/jakarta)
> spec handling in a custom fashion an error case.
> Typically the case where we can exclude the TCK since it is irrelevant for
> our impl but I understand also it is not perfect.
>
>
> >
> > I appreciate that this introduces a backwards incompatible change, and
> that
> > there may be other consumers of the library that would have an issue if
> > this just changed. This seems like a fairly straightforward case that
> could
> > be easily and quickly solved with a feature switch, and passing the TCK
> is
> > a worthwhile goal, both for Johnzon and TomEE. I suspect the TCK
> challenge
> > will take a bit of time, and we'll likely end up back at the feature
> switch
> > anyway.
> >
>
> Issue is we dont have a Json.createPointerFactory(mapWithToggle) so it is a
> global flag which means it breaks some deployments anyway - at least at
> tomee level - when > 1 app is deployed (or >= 1 app + 1 extension).
>
>
> >
> > On Fri, Nov 27, 2020 at 10:44 AM Romain Manni-Bucau <
> rmannibu...@gmail.com
> > >
> > wrote:
> >
> > > Hi JL,
> > >
> > > As discussed together - but sharing for others - we must take into
> > account
> > > some points:
> > >
> > > 1. reading both spec, JSON-Patch enables to handle /- as your first did
> > (ie
> > > consider it is last element). JSON-Patch uses JSON-Pointer but nowhere
> it
> > > is written it behaves as JSON-Pointer in all cases and it is typically
> > > "integration" definition which can extend an underlying spec (otherwise
> > > most of EE wouldn't be right? ;))
> > >
> >
> > I think the idea is that it references a non-existent element, *after*
> the
> > last element in an array. So if you have an array [0, 1, 2, 3, 4], then
> > "/-" would reference element _5_ (assuming you start your numbering at
> 0),
> > and not the last element in the array (index 4).
> >
>
> This is the jsonpointer spec right,  but JSONPatch never requires to not
> handle the case as we do, it is just not written (and why we used it also).
> Issue on jsonpointer side being we can't have another character which means
> "last element".
>
>
> >
> >
> > > 2. On johnzon point of view we can't break this feature which was
> > requested
> > > by user and transitive users (ie user of products built with johnzon)
> > > without at least a clear migration path so if we want to break we
> should
> > do
> > > a 1.3 (dont think we need a 1.2 maintenance branch, we can do it
> lazily),
> > > document how to migrate from current behavior to new one (i'll detail
> it
> > > after) and communicate on it on our website properly (index.html ref
> and
> > > dedicated page I guess with the release annoucement). Alternative is to
> > > challenge the TCK, it is a failure case so it is typically the kind of
> > case
> > > we can plug custom/vendor behavior (we do in other parts of the JSON-B
> > spec
> > > for ex). Overall idea is to not let users on the road because some TCK
> > > exist (functional and users over procedural work).
> > >
> >
> > I'd be interested in the history, it helps to be mindful of it when
> making
> > changes.
> >
>
> Goal is to be able to work on the last element, there is nothing in specs
> about this one but it is very common to need that (see it as "length"
> operator).
> Indeed we can enrich jsonlogic module to cover that 

Re: JSON Pointer/Patch issue with /-

[Romain Manni-Bucau]

Le mar. 1 déc. 2020 à 14:40, Jonathan Gallimore <
jonathan.gallim...@gmail.com> a écrit :

> I'll address a few points inline below, but at a high level, what are we
> looking to achieve from a spec/tck challenge?
>
> I can see a case for some clarification and updates to the Javadoc.
>
> The assertions that /- will return an error (as that references an index to
> append to after the *end* of an array - i.e. array.length) are tested in
> the TCK, and other implementations must be passing that TCK. It's hard to
> see a spec change happening, as there is no spec document beyond the RFCs
> that I can find. A TCK change that would enable Johnzon to pass, and
> require other currently passing implementations to make a change seems
> unlikely. Jakarta EE 8's TCK has been around a while and has
> implementations that pass. The Jakarta EE 9 TCK is basically "done" and is
> essentially the same as EE8, bar the namespace change. I guess adding a
> test exclude is possible, but serves to make this more vague and vendor
> dependent (and non-portable) which feels like it defeats the purpose -
> surely having it better defined and tested is the way to go.
>

Well, here the fact is that it does not impact other vendors since it is a
johnzon vendor specific feature we put in a shadow of the (javax/jakarta)
spec handling in a custom fashion an error case.
Typically the case where we can exclude the TCK since it is irrelevant for
our impl but I understand also it is not perfect.


>
> I appreciate that this introduces a backwards incompatible change, and that
> there may be other consumers of the library that would have an issue if
> this just changed. This seems like a fairly straightforward case that could
> be easily and quickly solved with a feature switch, and passing the TCK is
> a worthwhile goal, both for Johnzon and TomEE. I suspect the TCK challenge
> will take a bit of time, and we'll likely end up back at the feature switch
> anyway.
>

Issue is we dont have a Json.createPointerFactory(mapWithToggle) so it is a
global flag which means it breaks some deployments anyway - at least at
tomee level - when > 1 app is deployed (or >= 1 app + 1 extension).


>
> On Fri, Nov 27, 2020 at 10:44 AM Romain Manni-Bucau  >
> wrote:
>
> > Hi JL,
> >
> > As discussed together - but sharing for others - we must take into
> account
> > some points:
> >
> > 1. reading both spec, JSON-Patch enables to handle /- as your first did
> (ie
> > consider it is last element). JSON-Patch uses JSON-Pointer but nowhere it
> > is written it behaves as JSON-Pointer in all cases and it is typically
> > "integration" definition which can extend an underlying spec (otherwise
> > most of EE wouldn't be right? ;))
> >
>
> I think the idea is that it references a non-existent element, *after* the
> last element in an array. So if you have an array [0, 1, 2, 3, 4], then
> "/-" would reference element _5_ (assuming you start your numbering at 0),
> and not the last element in the array (index 4).
>

This is the jsonpointer spec right,  but JSONPatch never requires to not
handle the case as we do, it is just not written (and why we used it also).
Issue on jsonpointer side being we can't have another character which means
"last element".


>
>
> > 2. On johnzon point of view we can't break this feature which was
> requested
> > by user and transitive users (ie user of products built with johnzon)
> > without at least a clear migration path so if we want to break we should
> do
> > a 1.3 (dont think we need a 1.2 maintenance branch, we can do it lazily),
> > document how to migrate from current behavior to new one (i'll detail it
> > after) and communicate on it on our website properly (index.html ref and
> > dedicated page I guess with the release annoucement). Alternative is to
> > challenge the TCK, it is a failure case so it is typically the kind of
> case
> > we can plug custom/vendor behavior (we do in other parts of the JSON-B
> spec
> > for ex). Overall idea is to not let users on the road because some TCK
> > exist (functional and users over procedural work).
> >
>
> I'd be interested in the history, it helps to be mindful of it when making
> changes.
>

Goal is to be able to work on the last element, there is nothing in specs
about this one but it is very common to need that (see it as "length"
operator).
Indeed we can enrich jsonlogic module to cover that case but most users
just bring jsonp+jsonb and not johnzon-jsonlogic.


>
>
> >
> > On strict TCK side, we can also do a johnzon-tck module where we wrap the
> > provider to handle that case and pass the TCK, this is purely technical
> to
> > be compliant but would avoid to break anything.
> > Now if we really want to be strict in our implementation we must still
> > enable this last element case. One option not far from what we have is to
> > use our json-logic module and add some jsonpatch operators. Combining
> > multiple operators we can manage to fulfill this common patching need -
> but

Re: JSON Pointer/Patch issue with /-

[Jonathan Gallimore]

I'll address a few points inline below, but at a high level, what are we
looking to achieve from a spec/tck challenge?

I can see a case for some clarification and updates to the Javadoc.

The assertions that /- will return an error (as that references an index to
append to after the *end* of an array - i.e. array.length) are tested in
the TCK, and other implementations must be passing that TCK. It's hard to
see a spec change happening, as there is no spec document beyond the RFCs
that I can find. A TCK change that would enable Johnzon to pass, and
require other currently passing implementations to make a change seems
unlikely. Jakarta EE 8's TCK has been around a while and has
implementations that pass. The Jakarta EE 9 TCK is basically "done" and is
essentially the same as EE8, bar the namespace change. I guess adding a
test exclude is possible, but serves to make this more vague and vendor
dependent (and non-portable) which feels like it defeats the purpose -
surely having it better defined and tested is the way to go.

I appreciate that this introduces a backwards incompatible change, and that
there may be other consumers of the library that would have an issue if
this just changed. This seems like a fairly straightforward case that could
be easily and quickly solved with a feature switch, and passing the TCK is
a worthwhile goal, both for Johnzon and TomEE. I suspect the TCK challenge
will take a bit of time, and we'll likely end up back at the feature switch
anyway.

On Fri, Nov 27, 2020 at 10:44 AM Romain Manni-Bucau 
wrote:

> Hi JL,
>
> As discussed together - but sharing for others - we must take into account
> some points:
>
> 1. reading both spec, JSON-Patch enables to handle /- as your first did (ie
> consider it is last element). JSON-Patch uses JSON-Pointer but nowhere it
> is written it behaves as JSON-Pointer in all cases and it is typically
> "integration" definition which can extend an underlying spec (otherwise
> most of EE wouldn't be right? ;))
>

I think the idea is that it references a non-existent element, *after* the
last element in an array. So if you have an array [0, 1, 2, 3, 4], then
"/-" would reference element _5_ (assuming you start your numbering at 0),
and not the last element in the array (index 4).


> 2. On johnzon point of view we can't break this feature which was requested
> by user and transitive users (ie user of products built with johnzon)
> without at least a clear migration path so if we want to break we should do
> a 1.3 (dont think we need a 1.2 maintenance branch, we can do it lazily),
> document how to migrate from current behavior to new one (i'll detail it
> after) and communicate on it on our website properly (index.html ref and
> dedicated page I guess with the release annoucement). Alternative is to
> challenge the TCK, it is a failure case so it is typically the kind of case
> we can plug custom/vendor behavior (we do in other parts of the JSON-B spec
> for ex). Overall idea is to not let users on the road because some TCK
> exist (functional and users over procedural work).
>

I'd be interested in the history, it helps to be mindful of it when making
changes.


>
> On strict TCK side, we can also do a johnzon-tck module where we wrap the
> provider to handle that case and pass the TCK, this is purely technical to
> be compliant but would avoid to break anything.
> Now if we really want to be strict in our implementation we must still
> enable this last element case. One option not far from what we have is to
> use our json-logic module and add some jsonpatch operators. Combining
> multiple operators we can manage to fulfill this common patching need - but
> we break the overall API + require a new module to be added to apps).
>
> Lastly I would note that JSON Pointer *enables* our impl:
>
> > Note that the use of the "-" character to index an array will always
>
>result in such an error condition because by definition it refers to
>a nonexistent array element.  Thus, applications of JSON Pointer need
>to specify how that character is to be handled, if it is to be
>useful.
>
>
> >  For example, some applications might stop pointer processing upon an
>
>error, while others may attempt to recover from missing values by
>inserting default ones.
>
>
> Literally means "this is a case we consider as an error but your
> application can recover from it" and we do ;).
>

Sort of. "applications of JSON Pointer need to specify how that character
is to be handled". What's the definition of "application of JSON pointer"?
In the case of TomEE, I'd suggest the "application" is Jakarta EE, which
has specified that an error should be thrown. In a standalone case, is the
application whatever is consuming Johnzon, or Johnzon itself?


> Since it is an error case I would start by challenging the TCK to make it
> vendor dependent and exclude it from the passing list for now.
> If really blocking we can go with plan B and try to have a migration 

Re: JSON Pointer/Patch issue with /-

[Romain Manni-Bucau]

Hi JL,

As discussed together - but sharing for others - we must take into account
some points:

1. reading both spec, JSON-Patch enables to handle /- as your first did (ie
consider it is last element). JSON-Patch uses JSON-Pointer but nowhere it
is written it behaves as JSON-Pointer in all cases and it is typically
"integration" definition which can extend an underlying spec (otherwise
most of EE wouldn't be right? ;))
2. On johnzon point of view we can't break this feature which was requested
by user and transitive users (ie user of products built with johnzon)
without at least a clear migration path so if we want to break we should do
a 1.3 (dont think we need a 1.2 maintenance branch, we can do it lazily),
document how to migrate from current behavior to new one (i'll detail it
after) and communicate on it on our website properly (index.html ref and
dedicated page I guess with the release annoucement). Alternative is to
challenge the TCK, it is a failure case so it is typically the kind of case
we can plug custom/vendor behavior (we do in other parts of the JSON-B spec
for ex). Overall idea is to not let users on the road because some TCK
exist (functional and users over procedural work).

On strict TCK side, we can also do a johnzon-tck module where we wrap the
provider to handle that case and pass the TCK, this is purely technical to
be compliant but would avoid to break anything.
Now if we really want to be strict in our implementation we must still
enable this last element case. One option not far from what we have is to
use our json-logic module and add some jsonpatch operators. Combining
multiple operators we can manage to fulfill this common patching need - but
we break the overall API + require a new module to be added to apps).

Lastly I would note that JSON Pointer *enables* our impl:

> Note that the use of the "-" character to index an array will always

   result in such an error condition because by definition it refers to
   a nonexistent array element.  Thus, applications of JSON Pointer need
   to specify how that character is to be handled, if it is to be
   useful.


>  For example, some applications might stop pointer processing upon an

   error, while others may attempt to recover from missing values by
   inserting default ones.


Literally means "this is a case we consider as an error but your
application can recover from it" and we do ;).

Since it is an error case I would start by challenging the TCK to make it
vendor dependent and exclude it from the passing list for now.
If really blocking we can go with plan B and try to have a migration path
but it sounds like a lot of effort for everyone for literally 0 gain IMHO.

Hope it makes sense.

Romain Manni-Bucau
@rmannibucau  |  Blog
 | Old Blog
 | Github  |
LinkedIn  | Book



Le ven. 27 nov. 2020 à 10:59, Jean-Louis Monteiro 
a écrit :

> Hi,
>
> I was working to pass the TCK with Johnzon, but I have failures around the
> usage of "/-" in arrays.
>
> From JSON Pointer RCF https://tools.ietf.org/html/rfc6901
>
> > If the currently referenced value is a JSON array, the reference
> >   token MUST contain either:
> >
> >   *  characters comprised of digits (see ABNF below; note that
> >  leading zeros are not allowed) that represent an unsigned
> >  base-10 integer value, making the new referenced value the
> >  array element with the zero-based index identified by the
> >  token, or
> >
> >   *  exactly the single character "-", making the new referenced
> >  value the (nonexistent) member after the last array element.
> >
> >
> And then
>
> > Note that the use of the "-" character to index an array will always
> >result in such an error condition because by definition it refers to
> >a nonexistent array element.  Thus, applications of JSON Pointer need
> >to specify how that character is to be handled, if it is to be
> >useful.
> >
> >
> When I opened https://issues.apache.org/jira/browse/JOHNZON-325
> I first fixed with
>
> https://github.com/apache/johnzon/pull/68/commits/3ef4fb80bdaf6010d4ad66c481675b70bc1e4bca
>
> And we were 100% JSONP compliant but as you can see in the commit, I had
> to @Ignore some junit tests because they did not make sense.
>
> After talking with Romain, he mentioned some improvements to attempt to be
> backward compatible and still support the previous behavior.
> See commit
>
> https://github.com/apache/johnzon/pull/68/commits/2626806f82b076ada11800221c8458da8ec53794
>
> But unfortunately this is breaking the spec and the TCK.
> My understanding of JSON Pointer and as per the 2 quotes in this email, I
> think using /- for anything but ADD does not make sense and must fail (and
> this