For background: Tekton has emerged out of the former Knative Build-Pipelines project. The Build API connection will be dropped in Serving v1beta1. Tekton is the way to go if any.
Cheers, Markus Am Mo., 20. Mai 2019 um 17:03 Uhr schrieb Martin Henke <martin.he...@web.de >: > Tekton is different but very very similar. You get a lot of DejaVus. No > big learning Curve. > > Martin > > > > On 20. May 2019, at 17:00, Michele Sciabarra <mich...@sciabarra.com> > wrote: > > > > Ok great, I see the discussion is starting to bring ideas. > > > > Yes my goal is basically to run existing actions in Knative, create and > invoke. And possibile retain the ability of an action to invoke another > action. > > > > I understand the different way they expose services, so I am rethinking > the idea of using a "work-alike" path. > > > > If it is needed we can add it with an ingress but it may be not > necessary in the initial implementation. > > > > Also I checked a bit ML and discussions and I see this Tekton thing that > should be the preferred way. > > > > Not sure if I understand the relation with the current Build API > documented in the website. Is Tekton "compatible" or it has a different API? > > > > > > -- > > Michele Sciabarra > > mich...@sciabarra.com > > > > ----- Original message ----- > > From: "Markus Thömmes" <markusthoem...@apache.org> > > To: dev@openwhisk.apache.org > > Subject: Re: A plan to (re) implement OpenWhisk on top of Knative > > Date: Monday, May 20, 2019 4:50 PM > > > > Good discussion, thanks! > > > > Can we try to define what the desired end-goal is here? I'm a bit unclear > > what resembling the OpenWhisk API actually buys us. > > > > To me, the desired end-state would be to run OpenWhisk actions as-is on a > > Knative cluster (similar to OpenFaaS' and Azure's integration). There's > no > > good way for us to provide the full API without spinning up a control > plane > > and we can only handle so much via the CLI. So to me, the end-goal looks > > like: > > > > 1. *wsk action create* actually doing all the pieces necessary to run a > > piece of code on Knative. > > 2. *wsk action invoke* doing some HTTP call under the hood to "invoke" > that > > action. The action should be reachable via a sensible URL. If we really > > want to keep the API surface (as I said, I'm dubious here) we can also do > > that via ingress level abstractions (like VirtualService). > > > > Cheers, > > Markus > > > > Am Mo., 20. Mai 2019 um 15:33 Uhr schrieb Martin Henke < > martin.he...@web.de > >> : > > > >> > >>> On 20. May 2019, at 14:55, Michele Sciabarra <mich...@sciabarra.com> > >> wrote: > >>> > >>>> Michele, > >>> > >>>> I like the idea to make the ActionLoop based runtimes to be runnable > on > >> Knative. > >>>> > >>>> My thoughts on this: > >>>> - I second Markus concern to implement the invocation API onto Knative > >> instead of just using Knative service syntax. > >>> Can you elaborate this? I do not understand. > >> > >> Knative service syntax: https://<service(in our case = > >> action)>.<namespace>.<host>/ > >> OW invocation https:// > >> <api-host>/api/v1/namespaces/<namespace>/actions/<action> > >> > >> (I personally so no worth in inventing a distinct API for OW images, but > >> as said I would see that as a valid optional feature) > >> > >>> > >>>> - I would have concerns to make it dependent on Gloo which is kind of > a > >> minority choice for Knative load balancing > >>> I do not think it will be hard to setup a test also using Istio, I do > >> not want to be limited to Gloo. > >> > >> I just wanted to prevent that Gloo gets a “official” prerequisite for an > >> “official” OW on Knative flow. > >> It is of course free to you to use what ever you want to do in your > >> prototype. > >> > >>> - In my opinion the goal should be to have some uniform behaviour for > >> ActionLoop based runtimes > >>>> and other ones like the adapted NodeJS runtimes demonstrated by Matt > >> and Priti > >>> As much as I can tell the current implementation is just the building > >> and exposing the "/init" and "/run" but I can be wrong. > >>> The build can be of course reused, so it continues the effort. For the > >> frontend, from the documentation I think Matt wants to add a proxy, > while I > >> would like to implemeent the "invocation" straight in the runtime. This > is > >> open to discussion, but of course it is better to reach an agreement. > >> > >> Also in the work of Priti and Matt the invocation goes directly to the > >> runtime. The action code is either passed with the call (not yet tested > by > >> me) or set via environment variable in the docker build. > >> > >>> > >>>> - As Knative Build seems be on a dead end I would propose to target > >> Tekton as the build system (which developed as kind of >successor out of > >> Knative) > >>> > >>> If Knative build is dead then it would be a bit unfair that they change > >> it as the scope of the Knative project! > >>> It looks like the goal is to setup some standards! And I would be very > >> disappointed to know that. > >> > >> Tekton evolved out of Knative Build (or more correct out of Knative > >> Pipelines) but is very similar to the Knative build. > >> Flows can easily be ported from one to the other, > >> If we target Tekton build we would target the platform were the Knative > >> build team is focusing on. > >> But again feel free to use whatever platform for your prototype work. > >> > >>> At this stage the build is the more interesting thing, and it could be > >> even imported in main openwhisk to speed up deployment. > >>> I have already baked it in the ActionLoop runtimes (with > precompilation). > >>> Also if we use Tekton, where is the Knative standard then? What is the > >> point? We can build our own system instead of "Knativizing" it... > >>> > >>>> Maybe it would be a good solution to tackle two things independently. > >>>> 1) Design and implement a common protocol of building, running and > >> calling OW runtimes on Knative > >>>> 2) Implement the OW invocation API on top of Knative as an additional > >> option for those who have the need to expose it. > >>> > >>> On this, for my personal approach at building things, I want something > >> that works and it is complete and useful. A "MVP”. > >> > >> Cool. Just go on. > >> > >>> So I do not plan to split the effort. Version 0.1 must be a minimal > >> working subset of OpenWhisk on Knative. > >>> Because otherwise there will be incomplete useless inusable pieces > >> around (see for example kwsk). > >>> > >>> It does not mean that things cannot be modular, nor that everyone must > >> but to me "openwhisk-knative" must be a single repo with all the pieces > to > >> make something where you can download is and deploy in a kubernetes > cluster > >> and be able to deploy simple actions. When this works, we can improve > >> incrementally and split it but keeping it working. > >>> > >>>> I would looking forward to work with you on the first work item. > >>> Great but I see now more details to discuss before we can start. Most > >> notably I need to understand how I can build on top of Mark and Priti > work > >> and continue their work. ANd I can even probably recover some of the > code > >> of kwsk as they implemented some openwhisk api, that I want now in the > >> runtime. > >>> > >> > >> I do not want to stop you in any way. My hope is that the action loop > >> runtimes and the “other ones” do expose the same behaviour when being > >> called. So that the users is not surprised when calling different > actions > >> in different languages. > >> And behaving the same way might also mean to adapt the “other languages” > >> to the same behaviour as the action loop based ones. > >> They just should be uniform to be used. > >> > >> When your prototype is accessible it would be a good point of time to > >> discuss this. > >> > >> As said I very much like your effort. > >> > >>> > >>>> On 20. May 2019, at 08:55, Michele Sciabarra <mich...@sciabarra.com> > >> wrote: > >>>> > >>>> > >>>>>> I have an idea for implementing a prototype of OpenWhisk on top of > >> Knative. > >>>>>> My basic ideas are: do not use any proxy, forwarding or adapter: > >> extend > >>>>>> the runtime to support the REST call and expose them as ingress. And > >> use a > >>>>>> wrapper on top of `kubectl` to generate all the needed components. > >>>> > >>>>> Does this tie into the work that Matt was doing to the runtimes to > make > >>>>> them runnable on Knative? Is this lined up with that at all? > >>>> Actually yes. He suggested I can investigate how to migrate ActionLoop > >> to port many other languages to Knative. > >>>> Also he recommended I add my idea and this is what I am doing. Current > >> code is, if I am not wrong, a Knative build of the nodejs runtime. > >>>> > >>>> There has been a number of attempts and proposal to move forward > >> OpenWhisk. My idea that to succeed we need something small but that just > >> works. This is my idea to be able to implement in the shorter time frame > >> possible an actual subset of OpenWhisk that works and it is truly built > on > >> top of Knative. So I am putting the thing a bit further than Matt work. > >>>> > >>>> > >>>>>> My goal is to have a functional work-alike of OpenWhisk built on top > >> of > >>>>>> Knative, using ActionLoop as a foundation. I will extend ActionLoop > to > >>>>>> support the required REST calls of OpenWhisk. > >>>>> > >>>>>> I also want to create tool, I will call `wskn`. This tool will > >> initially > >>>>>> just a python script, a wrapper on top of `kubectl` as it will > >> generate > >>>>>> kubernetes descriptors. > >>>>> Why not build this into "wsk" itself? The Azure Functions CLI as an > >> example > >>>>> supports multiple deployment types like this in one CLI. > >>>> > >>>> When it will works, yes, of course. But to start, what I really need > is > >> a prototype that can generate kubernetes descripttors to feed to > kubectl, > >> so a simplee, quick and ditry, separate tool (that I will keep together > >> the runtime) is all I need for now. > >>>> > >>>>>> > >>>>>> It will support initially just the the action creation and > >> invocation, and > >>>>>> only synchronous (blocking) behaviour, as all the request will go > >> straight > >>>>>> to the runtimes. Hopefully also a subset of `package` and > >> `activation`. > >>>>>> Again triggers, rules, asynchronous for later. > >>>>>> > >>>>>> The idea is that you will be able to create actions and web actions > >> that > >>>>>> can run existing OpenWhisk actions, at least those with blocking > >> behaviour > >>>>>> that run with ActionLoop (Go, Java, Python, PHP, Swift, Rust, Ruby, > >>>>>> Crystal...) > >>>>>> > >>>>>> Implementation. > >>>>>> ============== > >>>>>> > >>>>>> This is how I plan to implement it. > >>>>>> > >>>>>> At this stage I want to use just Knative Serving and Knative Build, > >> using > >>>>>> Gloo for the ingress part. I also plan to install a local Docker > >> registry > >>>>>> Kubernetes registry, so we do not have to use DockerHub for > >> everything. All > >>>>>> of this can be done with existing command line tools in a few > minutes > >> in > >>>>>> any running Kubernetes deployment. > >>>>>> > >>>> > >>>>> Why specifying Gloo here? Do you need anything specific from Gloo > >> itself? > >>>>> If not I'd propose to just keep it on a Knative Serving API surface > >> level. > >>>> I want to build it on top of Knative serving, full stop. Currently, > >> installing Gloo is pretty easy and is more lightweight than Istio so I > >> will use it for my first implementation. > >>>> > >>>>>> > >>>>>> When I create an action, it will use Knative build that will work > >> roughly > >>>>>> in this way: > >>>>>> > >>>>>> - create a configmap with the action code > >>>>>> - build the actin using ActionLoop precompilation feature that will > >> return > >>>>>> a zip file including all the needed to run the action > >>>>>> - create a new docker image extending the runtime with the new zip, > >> using > >>>>>> Kaanico > >>>>>> - push the image in the local registry > >>>>> This feels like a fairly heavyweight process, we should be able to > >> come up > >>>>> with a way to circumvent zipping entirely. Maybe the runtime can > detect > >>>>> that the unzipped content is already there and skip the unzip step? > >>>> > >>>> Actually this is my first idea of how to use Knative build. And is not > >> complicated: when I create the action, a run a build that includes > Kanico. > >> I generate a Dockerfile on the fly. The docker file uses the action > runtime > >> that already know how to compile a script. And then I save an image. I > >> already implemented un "autoinit" so just launching the image will give > a > >> runtime ready to run that execute an action already compiled. > >>>> > >>>> > >>>>> I'm fairly hesitant on the usage of a ConfigMap for storing the > action > >>>>> code. It's all stored in the in-cluster etcd instance and it has a > >> limit of > >>>>> 1M. This is at most a stop-gap solution to provide a PoC I think. Any > >> ideas > >>>>> on how to "productize" this? > >>>> > >>>> ConfigMap can be mounted as files, so it is an easy way to feed an > >> action to a build. It is just an easy way to feed the action code to the > >> Build. > >>>> > >>>> My initial constraint is that I want just to generate Kubernetes > >> descriptors to feed to kubectl. > >>>> Of course in the long run I can add some "file upload" storage. > >>>> > >>>> If I could to this file upload when invoking a build it could ideal as > >> I do not have to store anything anywhere, just process the code and > >> generate a single layer to execute actions to be store in the registry. > >>>> I will investigate better this area, I understand your concern. > >>>> > >>>>> > >>>>>> At this point you can run the action. ActionLoop will be extended to > >>>>>> support invocations in the format > >>>>>> "/v1/namespaces/namespace/actions/package/action". > >>>>> Why bother reimplementing this exact path? To obtain API > compatibility > >> with > >>>>> OpenWhisk as it is today? > >>>> > >>>> I want to implement a subset of the OpenWhisk API on top of Knative > >> serving. > >>>> Knative serving already does the scaling and routing, so what we need > >> are the "endpoints" to invoke actions. > >>>> > >>>> Since I do not want to add additional components, not at the first > >> stage. Just knative serve and build, the runtime and a controller > script, > >> the runtime is the natural place where to "handle" the API invocations, > >> since Knative only generates the URL but not anything else. If I > >> understood well, Matt is adding a proxy. I do not want to add a proxy, > just > >> add to the runtime the ability to respond to "API like" calls, at least > >> those regarding action invocation. > >>>> > >>>>>> It will do all the decoding required to invoke the action with the > >>>>>> expected paramenters (straight invocation thrhoug the actinloop > >> protocol, > >>>>>> not proxies). > >>>>> Does this mean moving all of the Controller's "smartness" about > >> incoming > >>>>> and outgoing HTTP requests (see the whole WebActions for example)? > >>>> > >>>> At least decoding web actions in the runtime, yes. Knative serving > >> already has routing and proxying. > >>>> So a true implementation on top of Knative requires IHMO this > >> sacrifice. Unless there is a way to keep the controller in a "Knative" > >> compatible way. Open to suggestions here. > >>>> > >>>>> Each action will then be exposed using an ingress with its specific > >>>>> invocation path. > >>>>> > >>>>> If the community agrees with this plan, I would create a repo > >>>>> `incubator-openwhisk-knative` to work on it. > >>>>> > >>>>> Thoughts? > >> > >> > >
