[RFR] 8160768: Add capability to custom resolve host/domain names within the default JDNI LDAP provider

[Rob McKenna]

You've cracked my elabourate webrev naming scheme. Thanks Daniel,

On 06/11/18 16:39, Daniel Fuchs wrote:
> Hi Rob,
> 
> Assuming the new webrev is:
> 
> http://cr.openjdk.java.net/~robm/8160768/webrev.09
> 
> then it looks much better to me.
> 
> I haven't re-reviewed everything in details -  just looked
> at the updates (LdapDnsProviderService,
> LdapDnsProvider signature change, ServiceLocator)
> 

Yep, apart from the volatile service nothing else has changed.

> BTW: if I'm not mistaken returning an empty Optional is
> equivalent, in the end, to returning an Optional containing
> a LdapDnsProviderResult which returns an empty list of endpoints?
> I guess that's OK, I don't see any value in preventing an
> LdapDnsProviderResult to have an empty endpoint list anyway.
> 

Basically, yes.

Thanks,

    -Rob

> best regards,
> 
> -- daniel
> 
> 
> On 06/11/2018 15:52, Rob McKenna wrote:
> > Thanks folks,
> > 
> > Vyom, I've updated service to be volatile.
> > 
> > On 30/10/18 14:25, Daniel Fuchs wrote:
> > > Hi Rob,
> > > 
> > > LdapCtxFactory.java
> > > 
> > >   187             for (String u : r.getEndpoints()) {
> > >   188                 try {
> > >   189                     ctx = getLdapCtxFromUrl(
> > >   190                             r.getDomainName(), new LdapURL(u), env);
> > >   191                 } catch (NamingException e) {
> > >   192                     // try the next element
> > >   193                     lastException = e;
> > >   194                 }
> > >   195             }
> > > 
> > > is a break statement missing after line 190?
> > > 
> > > If not then can you add a comment explaining why only the last
> > > context is retained (and returned?)
> > > 
> > > Alternatively, if a break is indeed missing, these three lines
> > > could be moved into the for loop above:
> > > 
> > >   206             // Record the URL that created the context
> > >   207             ctx.setProviderUrl(url);
> > >   208             return ctx;
> > > 
> > > and maybe lines 206-207 could be moved into the
> > > getLdapCtxFromUrl() method?
> > > 
> > 
> > Yes, you're right, we should return the first successful result.
> > 
> > > LdapDnsProviderService.java:
> > > 
> > > Why is this class non final? If it can be made final then
> > > the protected methods should probably become package.
> > > 
> > 
> > Good point, fixed.
> > 
> > > LdapDnsProvider.java:
> > > 
> > > It is strange to see new APIs with Hashtable in the method
> > > signature. I understand that our implementation will need
> > > an Hashtable at some point to call javax.naming.spi.NamingProvider,
> > > but how likely is it that a clean room implementation of
> > > a LdapDnsProvider will need to do that?
> > > 
> > > Maybe we could have Map<?,?> in the signature instead - and
> > > leave the burden to our implementation - somewhere in ServiceLocator,
> > > to adapt back to Hashtable where it needs to?
> > 
> > So I've altered the signature of the method to take a Map<?, ?> as
> > proposed. I've added a getLdapService(String domainName, Map<?,?> environment)
> > method to ServiceLocator which delegates to the existing method after
> > conversion. Hopefully this addresses your concerns.
> > 
> > I'll update the CSR accordingly once this review is complete.
> > 
> >      -Rob
> > 
> > > 
> > > 
> > > best regards,
> > > 
> > > -- daniel
> > > 
> > > 
> > > On 25/10/2018 17:34, Rob McKenna wrote:
> > > > This recently received CSR approval, so it seems like a good time to pick
> > > > the codereview up again:
> > > > 
> > > > http://cr.openjdk.java.net/~robm/8160768/webrev.08/
> > > > 
> > > > Referencing:
> > > > 
> > > > http://mail.openjdk.java.net/pipermail/core-libs-dev/2017-December/050794.html
> > > > 
> > > > 1) I'm copying the behaviour from
> > > > LdapCtxFactory.getInitialContext(Hashtable<?,?>) where an empty String is
> > > > the default value used when the provider url is null.
> > > > 
> > > > I don't think HostnameChecker (by way of SNIHostname) will accept either
> > > > empty or null values when doing the comparison.
> > > > 
> > > > Somewhat oddly however, LdapCtx.extendedOperation(ExtendedRequest)
> > > > appears to pass the String "null" to
> > > > StartTlsResponseImpl.setConnection(Connection, String), which attempts
> > > > to substitute null values with the Connections host so there may be a bug
> > > > here.
> > > > 
> > > > I'm happy to allow null returns here if necessary. Sean, can you
> > > > comment on the distinction between null & "" as far as hostname
> > > > verification is concerned?
> > > > 
> > > > 2) In the latest iteration lookupEndpoints() returns an
> > > > Optional<LdapDnsResult>. Currently neither getEndpoints() nor
> > > > getDomainName() can be null. (they can be an empty list and/or an empty
> > > > String however)
> > > > 
> > > > 3) Corrected.
> > > > 
> > > > 4) See https://www.oracle.com/technetwork/java/seccodeguide-139067.html#4-5
> > > > 
> > > >       -Rob
> > > > 
> > > 
>