Hi Robert Unsure if you read the previous emails in this thread. In my earlier response, I wrote
> 1. TBH, I have no strong feelings about persisting the federated principals. I think the biggest advantage I saw was to support SCIM along with 3p identity providers. But for this implementation, if we want to skip persisting principal entities, I'm ok with it. I feel that should address the majority of the concern you just expressed. Storing grants with references to some kind of FQN is certainly one approach, but IMO, is a massive undertaking with little benefit. For example, all of the grant APIs have to be modified to deal with target entities that don’t exist. How do we do validation for these APIs? Do these APIs now need to talk to external entities to ensure the caller didn’t misspell a role name or use all caps instead of mixed case? UI developers can’t simply populate a list of roles for a dropdown list unless they also connect directly to the idp. That makes it hard for someone to build a generic Polaris admin UI without also building support for Okta, Google, Apple, etc. On the other hand, SCIM is an industry standard for a reason. Every major IdP supports it - and I doubt it’s because they just don’t know any better. Supporting federated roles + SCIM means all the existing grant APIs Just Work and building generic privilege management tools/UI could be done today. Given the choice between a massive rewrite of the grant and authorization primitives with no user-facing benefit and supporting federated roles with the option of SCIM support in the future, the answer seems clear to me. Mike On Wed, Apr 30, 2025 at 7:04 AM Robert Stupp <sn...@snazy.de> wrote: > Hi, > > thanks Mike for the effort. > > However, I think that persisting principals, which are not "owned" by > Polaris, being persisted in Polaris is a good idea. How would changes to > a principal in the IdP be propagated to Polaris? What happens if a > principal that's deleted/disabled in the IdP - how is that reflected in > Polaris? What would happen if two Polaris instances concurrently > "transparently create" the same "federated principal entity"? > > Storing mirrored information that is only owned by an (external) IdP > leads to a "what's the source-of-truth" problem. > > A principal is (mostly) an individual user or service that can access > Polaris. The actual access-decision is up to the IdP (external IdP or > Polaris w/ its own principals). Each principal can also be uniquely > identified (IDP + principal-ID). > > I really do not think that principals owned by "external IdPs" should > ever be persisted in Polaris. > > Similar for roles manages by external IdPs. > > ACLs (grants) are (generally speaking) lists of grantee+privilege(s) > tuples. It is IMHO better to use a qualified reference to "IDP + > principal/role-ID". > > AFAIR it's only possbible to grant privileges to roles, not individual > principals. And if that's the case, I do not see a requirement to have > "federated principals" being persisted in Polaris at all. > > I seems the underlying issue here is the very tight coupling of > principals + principal-roles + catalog-roles + grants that requires a > unique integer-ID for each of those and using the same database-oriented > approach for role-membership management and catalog-entity grants. > > What's IMHO needed is a proper separation of those things, which should > happen now and after that's done integrate external IdPs. > > > On 22.04.25 17:00, Alex Dutra wrote: > > Hi Mike, > > > > Thanks for the historical context, that is really helpful. And I > completely > > agree with your last paragraph, and especially this: > > > > My preference would be to make this an immutable class that has the > >> principal entity and all active principal roles all in the constructor. > > > > I was arriving at the exact same conclusion – it's a pity that > > SecurityContext doesn't expose the principal roles. I guess, the problem > > now is how to move forward with this suggestion – I imagine a change > > in AuthenticatedPolarisPrincipal or in the Resolver would create > > repercussions in a lot of places in the code base as well as in existing > > PRs. > > > > Thanks, > > > > Alex > > > > On Mon, Apr 21, 2025 at 10:30 PM Michael Collado <collado.m...@gmail.com > > > > wrote: > > > >> Hey > >> > >> 1. I'm unsure why the Resolver was written to assume no role means all > >> roles. But I think it has to do with > >> 2. The Resolver was intended to be able to resolve principal roles, > grants, > >> and target entities all at one "snapshot" based on the entity and grant > >> versions returned by that loadEntitiesChangeTracking method. In order > to do > >> this in one shot, the authenticator couldn't resolve the principal roles > >> actually granted to the principal, so it didn't resolve the > >> PRINCIPAL_ROLE:ALL scope in the token. But that meant the Resolver > needed > >> to verify the grants existed for the roles to be assumed by the > principal > >> (otherwise, a caller could just put whatever role they want in the > scope). > >> To avoid the lookup during authn, ALL needed to be expanded by the > Resolver > >> based on the grants. This was an impedance to the federated role > proposal, > >> which stated that the authn token is authoritative regarding which roles > >> are granted to the principal (e.g., using a groups claim > >> < > >> > https://developer.okta.com/docs/guides/customize-tokens-groups-claim/main/ > >>> ). > >> That's why > >> 3. I added the ActiveRolesProvider interface so that the default impl > would > >> continue to validate the grants held by the principal for activating > >> principal roles but the federated alternative would delegate to the > token > >> claims (yet to be committed). > >> > >> Hopefully, that history helps. In short, I agree that > >> SecurityIdentity.getRoles() should be the right way to determine > activated > >> principal roles. The Resolver should rely on the authenticator to > determine > >> the active set of principal roles and not rely on grant records. The > >> AuthenticatedPolarisPrincipal doesn't really need to hold role names > >> anymore, but the resolver does still need the list of active > PrincipalRoles > >> to load the appropriate catalog roles. My preference would be to make > this > >> an immutable class that has the principal entity and all active > principal > >> roles all in the constructor. > >> > >> Mike > >> > >> On Sun, Apr 20, 2025 at 8:34 AM Alex Dutra > <alex.du...@dremio.com.invalid> > >> wrote: > >> > >>> Hi Mike, > >>> > >>> I am generally fine with the spec changes. > >>> > >>> I have however some concerns around the way we handle principal roles > >> today > >>> in Polaris, and as I was preparing the PR with support for external > IDPs > >>> [1], some oddities stood out: > >>> > >>> 1. The pseudo-role PRINCIPAL_ROLE:ALL seems, by convention, to be > >>> converted to an empty set of roles by the Authenticator; but I > wonder > >>> how we will be able to distinguish a token that contained no role > >> from a > >>> token that contained the pseudo-role. I added some changes to my > PR to > >>> be > >>> able to distinguish the two situations, but I think the general > >>> handling of > >>> this pseudo-role, as well as role mapping in general, deserves some > >> more > >>> thinking. The spec says this pseudo-role is "non-functional" – but > I > >>> don't > >>> know what this implies exactly. > >>> 2. AuthenticatedPolarisPrincipal exposes principal roles and this > is > >>> imho concerning for two reasons: first, the Resolver seems to > update > >> the > >>> principal roles during resolution, which makes the class mutable, > >>> potentially changing the principal characteristics *after* > >>> authentication. > >>> And secondly, this creates an ambiguity as roles can be accessed in > >> two > >>> ways: SecurityIdentity.getRoles() vs > >>> AuthenticatedPolarisPrincipal.getActivatedPrincipalRoles(). I > would be > >>> in favor of using the former consistently and completely removing > the > >>> latter. (Note: SecurityContext.isUserInRole() relies on the > former.) > >>> 3. There seems to be some overlap between the primary roles > >> resolution, > >>> done by the ActiveRolesProvider, and the role resolution done > later by > >>> the Resolver, cf. method > resolveCallerPrincipalAndPrincipalRoles(). I > >>> wonder if this second role resolution is really necessary? > Ultimately, > >>> the > >>> source of truth for role membership will always be > >>> SecurityIdentity.hasRole() or its JAX-RS variant, > >>> SecurityContext.isUserInRole(). We should not deviate from that. > >>> > >>> Thanks, > >>> > >>> Alex > >>> > >>> [1] https://github.com/apache/polaris/pull/1397 > >>> > >>> On Sat, Apr 19, 2025 at 2:47 AM Dmitri Bourlatchkov <di...@apache.org> > >>> wrote: > >>> > >>>> Re 2: Thanks for the clarification, Mike! I guess my brain swapped out > >> a > >>>> large portion of that doc :) > >>>> > >>>> I'm still not sure how IdentityToPrincipalMapping can help with > >> resolving > >>>> changes from API and from IdP integration. > >>>> > >>>> The doc talks about namespaces, but in PR# 1353, it looks like API > >> calls > >>>> are free to change anything in federated principal roles. > >>>> > >>>> Should IdentityToPrincipalMapping extend to validating changes coming > >>> from > >>>> the Admin API? > >>>> > >>>> Alternatively, we could treat that as a new permission and allow all > >>> admin > >>>> users to edit federated roles via API. > >>>> > >>>> Re 1: Yes, I guess it would be helpful with SCIM, but then we'd need > to > >>>> sync role membership, I guess. > >>>> > >>>> My understanding so far was that we'd get role membership at > >>> authentication > >>>> time and not persist it in Polaris. > >>>> > >>>> Is that still the plan? > >>>> > >>>> I think this relates to how we connect authentication and > authorization > >>> in > >>>> Polaris. If Principals are external, we get role membership from the > >>> access > >>>> token and all is clear. If Principals are local, and we still get > roles > >>>> from the access token, then the question arises about whether that > data > >>> is > >>>> in sync with local data (and the other way around too). > >>>> > >>>> That could be resolved by Polaris owning access tokens (via token > >>> exchange) > >>>> and assuming control over role membership based on local data and > >> access > >>>> time (I commented on this in the doc too). > >>>> > >>>> All in all, since SCIM is not part of phase 1 here, maybe we could > >> defer > >>>> dealing with federated Principal persistence, indeed. > >>>> > >>>> Re 3: I guess it also applies to client secret generation code, but > >> let's > >>>> see whether it actually causes too many conditions in code when it > >> comes > >>> to > >>>> that. > >>>> > >>>> Cheers, > >>>> Dmitri. > >>>> > >>>> On Thu, Apr 17, 2025 at 7:42 PM Michael Collado < > >> collado.m...@gmail.com> > >>>> wrote: > >>>> > >>>>> Thanks for the response. > >>>>> > >>>>> 1. TBH, I have no strong feelings about persisting the federated > >>>>> principals. I think the biggest advantage I saw was to support SCIM > >>> along > >>>>> with 3p identity providers. But for this implementation, if we want > >> to > >>>> skip > >>>>> persisting principal entities, I'm ok with it. > >>>>> > >>>>> 2. In the doc I wrote the following, which I think addresses the > >>> concern > >>>>> around conflicts. > >>>>> > >>>>> 1. > >>>>> > >>>>> The IdentityToPrincipalMapping should supply a naming convention > >> so > >>>> that > >>>>> PrincipalRoles and Principals created from that source do not > >>> conflict > >>>>> with > >>>>> entities created by a different IdentityProvider > >>>>> > >>>>> In the case that a role happens to exist even with the naming > >>> convention > >>>>> applied, the caller would be unable to authenticate with that role. > >>>>> > >>>>> 3. I don't think we need special classes for federated roles. In > >> nearly > >>>> all > >>>>> of the Polaris code, they are treated as PolarisRoleEntity without > >> any > >>>>> issue. The only code that needs to be aware of federated roles is > >>>>> > >>>>> a) The Admin API, which prevents granting these roles to principals > >> and > >>>>> b) The federated roles provider, which verifies that the federated > >>>>> principal is assuming federated roles. > >>>>> > >>>>> The rest of the code (i.e., the resolver and authorizer) treat these > >>>> roles > >>>>> exactly as native Polaris roles. > >>>>> > >>>>> Mike > >>>>> > >>>>> On Thu, Apr 17, 2025 at 2:39 PM Dmitri Bourlatchkov < > >> di...@apache.org> > >>>>> wrote: > >>>>> > >>>>>> Thanks for reviving this discussion, Mike! > >>>>>> > >>>>>> The API spec change by itself LGTM, but I have related concerns in > >>> how > >>>>> this > >>>>>> feature is meant to work in general. > >>>>>> > >>>>>> 1) The need to expose Federated Principals in Polaris API. > >>>>>> > >>>>>> The design doc [1] discusses the possibility to expose Federated > >>>>> Principals > >>>>>> in Polaris API, but there are pros and cons. I do not think it is a > >>>>> trivial > >>>>>> decision. I'd like to discuss this in more detail before we commit > >> to > >>>>> doing > >>>>>> that. > >>>>>> > >>>>>> From my POV the main benefit of exposing Federated Principals is to > >>> be > >>>>> able > >>>>>> to alter their properties in Polaris (as mentioned in the doc). > >>>> However, > >>>>>> your email indicates that this is actually forbidden. > >>>>>> > >>>>>> What use cases do you envision for exposing read-only Federated > >>>>> Principals? > >>>>>> 2) Reconciliation of Federated vs. Non-Federated changes. > >>>>>> > >>>>>> Let's focus on Principal Roles here (which are meant to be writable > >>> via > >>>>>> API). > >>>>>> > >>>>>> If users are able to make and change (I assume) Principal Roles via > >>>> API, > >>>>>> and federation code will also be creating and changing those roles, > >>>> what > >>>>> is > >>>>>> our approach to handling conflicts between those two streams of > >>>> changes? > >>>>>> Some examples for context (also mentioned in GH): > >>>>>> > >>>>>> A) A user creates normal Principal Role "A", and later role "A" is > >>>>>> discovered through Federation. > >>>>>> > >>>>>> B) A user edits Federated Role "B" and later properties of "B" are > >>>>> updated > >>>>>> through Federation (or the other way around). > >>>>>> > >>>>>> Do we want to control property edits based on the origin of the > >>>> property > >>>>>> (spec out a "namespace" for Federated properties)? > >>>>>> > >>>>>> 3) OO types > >>>>>> > >>>>>> Currently Principals and Principal Roles are represented by one > >> java > >>>> type > >>>>>> each. When federation comes into play, would it make sense to > >>> develop a > >>>>>> (java) type hierarchy for working with that data in Polaris code? > >> My > >>>> main > >>>>>> concern here is avoiding a maze of if/else statements throughout > >> the > >>>>>> Polaris codebase for supporting Federation. > >>>>>> > >>>>>> I guess our approach to this depends largely on the outcome of > >> topic > >>> 2 > >>>>>> above. > >>>>>> > >>>>>> WDYT? > >>>>>> > >>>>>> Thanks, > >>>>>> Dmitri. > >>>>>> > >>>>>> [1] > >>>>>> > >>>>>> > >> > https://docs.google.com/document/d/15_3ZiRB6Lhzw0nxij341QUdxEIyFGTrI9_18bFIyJVo/edit?tab=t.0#heading=h.cu1a1acu4lc5 > >>>>>> On Wed, Apr 16, 2025 at 6:44 PM Michael Collado < > >>>> collado.m...@gmail.com> > >>>>>> wrote: > >>>>>> > >>>>>>> Hey folks > >>>>>>> > >>>>>>> Some of you already know that I posted an initial PR to get > >>> federated > >>>>>>> principals/roles added. One thing that came out of the feedback > >>> was a > >>>>>> spec > >>>>>>> change to make it clear when federated identities can be used in > >>> the > >>>>>> APIs. > >>>>>>> Notably, federated principals cannot be created or updated, but > >> can > >>>> be > >>>>>>> returned in get/list calls, whereas federated roles *can* be > >>> created > >>>> by > >>>>>> the > >>>>>>> API. The latter is useful/necessary in order to be able to assign > >>>>>>> privileges to those roles without relying on the JIT creation on > >>>> login. > >>>>>>> Please check out the spec change here and let me know what you > >>> think > >>>> - > >>>>>>> > >> > https://github.com/apache/polaris/pull/1353/files#diff-52444bc79608edfae86ed0b46d171f7ef63c20090860d877e4e135168311a986 > >>>>>>> Mike > >>>>>>> > >>>>>>> On Tue, Dec 17, 2024 at 5:15 PM Dmitri Bourlatchkov > >>>>>>> <dmitri.bourlatch...@dremio.com.invalid> wrote: > >>>>>>> > >>>>>>>> Hi Mike, > >>>>>>>> > >>>>>>>> I left some comments in the doc, but overall it looks good to > >> me > >>> :) > >>>>>>>> I still think there are some hidden dependencies on > >> Persistence. > >>>> For > >>>>>>>> example, whether and how we can have composite keys for > >> persisted > >>>>>>> federated > >>>>>>>> entities... but I guess we can work that out later. > >>>>>>>> > >>>>>>>> Also, I think it is important for the Authorizer API to avoid > >>>>> assuming > >>>>>>> that > >>>>>>>> all principals are persisted. Specific authorizer > >> implementations > >>>>>>>> (including the default one) can certainly expect persisted > >>>>> principals, > >>>>>>> but > >>>>>>>> the API should require that for the sake of flexibility of > >>> possible > >>>>>>> AuthN/Z > >>>>>>>> extensions. WDYT? > >>>>>>>> > >>>>>>>> Cheers, > >>>>>>>> Dmitri. > >>>>>>>> > >>>>>>>> On Thu, Nov 14, 2024 at 7:43 PM Michael Collado < > >>>>>> collado.m...@gmail.com> > >>>>>>>> wrote: > >>>>>>>> > >>>>>>>>> Hey folks > >>>>>>>>> > >>>>>>>>> As discussed during the community sync, I've put together > >> some > >>>>>> thoughts > >>>>>>>> on > >>>>>>>>> how we'd add support for federated identities in Polaris. I > >>>> copied > >>>>>> over > >>>>>>>>> some of what I had in the issue at > >>>>>>>>> https://github.com/apache/polaris/issues/441 and put it into > >>> the > >>>>> doc > >>>>>>>> here: > >>>>>>>>> > >>>>>>>>> > >> > https://docs.google.com/document/d/15_3ZiRB6Lhzw0nxij341QUdxEIyFGTrI9_18bFIyJVo/edit?tab=t.0 > >>>>>>>>> . > >>>>>>>>> > >>>>>>>>> Please take a look when you get some time and let me know > >> what > >>>> you > >>>>>>> think. > >>>>>>>>> Given that our next community sync is scheduled for the > >>>>> Thanksgiving > >>>>>>>>> holiday in the US, it might be useful to schedule a meeting > >>>>>>> specifically > >>>>>>>>> for this. I can schedule that sync if needed. > >>>>>>>>> > >>>>>>>>> Mike > >>>>>>>>> > -- > Robert Stupp > @snazy > >
