Merge pull request #638 from ecordell/new-resolver

feat(resolver): take all subscriptions into account when resolving

Author: ecordell

Documentation/design/dependency-resolution.md

@@ -0,0 +1,74 @@
+# Dependency Resolution and Upgrades
+
+OLM manages the dependency resolution and upgrade lifecycle of running operators. In many ways, thes problems OLM faces are similar to other OS pacakge managers like `apt`/`dkpg` and `yum`/`rpm`.
+
+However, there is one constraint that similar systems don't generally have that OLM does: because operators are always running, OLM attempts to ensure that at no point in time are you left with a set of operators that do not work with each other. 
+
+This means that OLM needs to never:
+ 
+ - install a set of operators that require APIs that can't be provided
+ - update an operator in a way that breaks another that depends upon it
+ 
+The following examples motivate why OLM's dependency resolution and upgrade strategy works as it does, followed by a description of the current algorithm.
+
+# Example: Deprecate dependant API
+
+A and B are APIs (e.g. CRDs)
+
+* A's provider depends on B
+* B’s provider has a Subscription
+* B’s provider updates to provide C but deprecates B
+
+This results in:
+
+* B no longer has a provider
+* A no longer works
+
+This is a case we prevent with OLM's upgrade strategy.
+
+
+# Example: Version deadlock
+
+A and B are APIs
+
+* A's provider requires B
+* B's provider requires A
+* A's provider updates to (provide A2, require B2) and deprecate A
+* B's provider updates to (provide B2, require A2) and deprecate B
+
+If we attempt to update A without simultaneously updating B, or vice-versa, we won't be able to progress to new versions of the operators, even though a new compatible set can be found.
+
+This is another case we prevent with OLM's upgrade strategy.
+
+
+# Dependency resolution 
+
+A Provider is an operator which "Owns" a CRD or APIService.
+
+This algorithm will result in a successful update of a generation (in which as many operators which can be updated have been):
+
+```
+Consider the set of operators defined by running operators in a namespace:
+
+  For each subscription in the namespace:
+     if the subscription hasn't been checked before, find the latest CSV in the source/package/channel
+        provisionally add the operator to the generation
+     else
+        check for a replacement in the source/package/channel
+  
+  // Generation resolution
+  For each required API with no provider in gen:
+    search through prioritized sources to pick a provider
+    provisionally add any new operators found to the generation, this could also add to the required APIs without providers
+    
+  // Downgrade
+  if there are still required APIs that can't be satisfied by sources:
+    downgrade the operator(s) that require the APIs that can't be satisfied
+
+  // Apply
+  for each new operator required, install it into the cluster. Any newly resolved operator will be given a subscription to the channel/package/source it was discovered in.
+```
+
+The operator expansion loop is bounded by the total number of provided apis across sources (because a generation may not have multiple providers)
+
+The downgrade loop will eventually stop, though it may contract back down to the original generation in the namespace. Downgrading an operator means it was in the previous generation. By definition, either its required apis are satisfied, or will be satisfied by the downgrade of another operator.

Makefile

@@ -79,7 +79,7 @@ setup-bare: clean e2e.namespace
 	. ./scripts/install_bare.sh $(shell cat ./e2e.namespace) test/e2e/resources
 
 e2e:
-	go test -v -timeout 30m ./test/e2e/... -namespace=openshift-operators -kubeconfig=${KUBECONFIG} -olmNamespace=openshift-operator-lifecycle-manager
+	go test -v -timeout 50m ./test/e2e/... -namespace=openshift-operators -kubeconfig=${KUBECONFIG} -olmNamespace=openshift-operator-lifecycle-manager
 
 e2e-local:
 	. ./scripts/build_local.sh
@@ -108,6 +108,11 @@ vendor: $(KUBE_DEPS)
 container:
 	docker build -t $(IMAGE_REPO):$(IMAGE_TAG) .
 
+clean-e2e:
+	kubectl delete crds --all
+	kubectl delete apiservices.apiregistration.k8s.io v1alpha1.packages.apps.redhat.com
+	kubectl delete -f test/e2e/resources/0000_30_00-namespace.yaml
+
 clean:
 	@rm -rf cover.out
 	@rm -rf bin
@@ -156,7 +161,6 @@ verify-codegen: codegen
 	git diff --exit-code
 
 verify-catalog: schema-check
-	go test $(MOD_FLAGS) -v ./test/schema/catalog_versions_test.go
 
 generate-mock-client: 
 	$(MOCKGEN)

deploy/chart/templates/0000_30_00-namespace.yaml

@@ -4,7 +4,6 @@ metadata:
   name: {{ .Values.namespace }}
   labels:
     openshift.io/run-level: "1"
-    olm.components: "global"
 ---
 apiVersion: v1
 kind: Namespace

deploy/chart/templates/0000_30_13-operatorgroup.crd.yaml

@@ -66,8 +66,6 @@ spec:
                 pattern: ^\S+$
             serviceAccountName:
               type: string
-          required:
-          - selector
           type: object
         status:
           properties:

deploy/chart/templates/0000_30_16-operatorgroup-default.yaml

@@ -10,6 +10,5 @@ metadata:
   name: olm-operators
   namespace: {{ .Values.namespace }}
 spec:
-  selector:
-    matchLabels:
-      olm.components: "global"
+  targetNamespaces:
+    - {{ .Values.namespace }}

go.mod

@@ -1,63 +1,56 @@
 module github.com/operator-framework/operator-lifecycle-manager
 
 require (
-	bitbucket.org/ww/goautoneg v0.0.0-20120707110453-75cd24fc2f2c // indirect
-	github.com/BurntSushi/toml v0.3.1 // indirect
-	github.com/NYTimes/gziphandler v1.0.1 // indirect
-	github.com/beorn7/perks v0.0.0-20180321164747-3a771d992973 // indirect
-	github.com/boltdb/bolt v1.3.1 // indirect
-	github.com/coreos/bbolt v1.3.0 // indirect
-	github.com/coreos/etcd v3.3.9+incompatible // indirect
+	github.com/coreos/etcd v3.3.10+incompatible // indirect
 	github.com/coreos/go-semver v0.2.0
-	github.com/coreos/go-systemd v0.0.0-20180511133405-39ca1b05acc7 // indirect
-	github.com/coreos/pkg v0.0.0-20180928190104-399ea9e2e55f // indirect
-	github.com/dgrijalva/jwt-go v3.2.0+incompatible // indirect
-	github.com/docker/distribution v2.6.2+incompatible // indirect
-	github.com/elazarl/go-bindata-assetfs v1.0.0 // indirect
-	github.com/emicklei/go-restful v2.8.0+incompatible // indirect
-	github.com/emicklei/go-restful-swagger12 v0.0.0-20170926063155-7524189396c6 // indirect
-	github.com/evanphx/json-patch v3.0.0+incompatible // indirect
+	github.com/coreos/go-systemd v0.0.0-20181031085051-9002847aa142 // indirect
+	github.com/docker/distribution v2.7.0+incompatible // indirect
+	github.com/evanphx/json-patch v4.1.0+incompatible // indirect
 	github.com/ghodss/yaml v1.0.0
 	github.com/go-openapi/spec v0.17.2
-	github.com/go-openapi/strfmt v0.17.2 // indirect
-	github.com/go-openapi/validate v0.17.2 // indirect
+	github.com/go-openapi/strfmt v0.18.0 // indirect
+	github.com/go-openapi/validate v0.18.0 // indirect
 	github.com/golang/glog v0.0.0-20160126235308-23def4e6c14b
-	github.com/golang/groupcache v0.0.0-20181024230925-c65c006176ff // indirect
 	github.com/golang/mock v1.1.1
-	github.com/gorilla/websocket v1.4.0 // indirect
-	github.com/grpc-ecosystem/go-grpc-prometheus v1.2.0 // indirect
-	github.com/grpc-ecosystem/grpc-gateway v1.5.1 // indirect
-	github.com/hashicorp/golang-lru v0.5.0 // indirect
-	github.com/jonboulle/clockwork v0.1.0 // indirect
-	github.com/matttproud/golang_protobuf_extensions v1.0.1 // indirect
+	github.com/google/btree v0.0.0-20180813153112-4030bb1f1f0c // indirect
+	github.com/google/gofuzz v0.0.0-20170612174753-24818f796faf // indirect
+	github.com/googleapis/gnostic v0.2.0 // indirect
+	github.com/grpc-ecosystem/go-grpc-middleware v1.0.0 // indirect
+	github.com/grpc-ecosystem/grpc-gateway v1.6.3 // indirect
+	github.com/imdario/mergo v0.3.6 // indirect
+	github.com/inconshreveable/mousetrap v1.0.0 // indirect
+	github.com/json-iterator/go v1.1.5 // indirect
 	github.com/maxbrunsfeld/counterfeiter v0.0.0-20181017030959-1aadac120687
-	github.com/modern-go/reflect2 v1.0.1 // indirect
-	github.com/operator-framework/operator-registry v1.0.1
+	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
+	github.com/opencontainers/go-digest v1.0.0-rc1 // indirect
+	github.com/operator-framework/operator-registry v1.0.3
+	github.com/peterbourgon/diskv v2.0.1+incompatible // indirect
 	github.com/pkg/errors v0.8.0
-	github.com/prometheus/client_golang v0.8.0
-	github.com/prometheus/client_model v0.0.0-20180712105110-5c3871d89910 // indirect
-	github.com/prometheus/common v0.0.0-20180801064454-c7de2306084e // indirect
-	github.com/prometheus/procfs v0.0.0-20180725123919-05ee40e3a273 // indirect
-	github.com/sirupsen/logrus v1.1.1
-	github.com/soheilhy/cmux v0.1.4 // indirect
+	github.com/prometheus/client_golang v0.9.1
+	github.com/prometheus/common v0.0.0-20190104105734-b1c43a6df3ae // indirect
+	github.com/prometheus/procfs v0.0.0-20190104112138-b1a0a9a36d74 // indirect
+	github.com/sirupsen/logrus v1.2.0
 	github.com/spf13/cobra v0.0.3
-	github.com/stevvooe/resumable v0.0.0-20180830230917-22b14a53ba50 // indirect
+	github.com/spf13/pflag v1.0.3 // indirect
 	github.com/stretchr/testify v1.2.2
-	github.com/tmc/grpc-websocket-proxy v0.0.0-20171017195756-830351dc03c6 // indirect
-	github.com/ugorji/go v1.1.1 // indirect
-	github.com/xiang90/probing v0.0.0-20160813154853-07dd2e8dfe18 // indirect
-	golang.org/x/oauth2 v0.0.0-20181105165119-ca4130e427c7 // indirect
-	golang.org/x/tools v0.0.0-20181207222222-4c874b978acb // indirect
-	gopkg.in/natefinch/lumberjack.v2 v2.0.0-20170531160350-a96e63847dc3 // indirect
+	github.com/ugorji/go/codec v0.0.0-20181209151446-772ced7fd4c2 // indirect
+	go.uber.org/atomic v1.3.2 // indirect
+	go.uber.org/multierr v1.1.0 // indirect
+	go.uber.org/zap v1.9.1 // indirect
+	golang.org/x/crypto v0.0.0-20181015023909-0c41d7ab0a0e // indirect
+	google.golang.org/genproto v0.0.0-20181016170114-94acd270e44e // indirect
+	google.golang.org/grpc v1.16.0
+	gopkg.in/inf.v0 v0.9.1 // indirect
+	gopkg.in/natefinch/lumberjack.v2 v2.0.0 // indirect
 	k8s.io/api v0.0.0-20181203235848-2dd39edadc55
 	k8s.io/apiextensions-apiserver v0.0.0-20181204003618-e419c5771cdc
 	k8s.io/apimachinery v0.0.0-20181203235515-3d8ee2261517
 	k8s.io/apiserver v0.0.0-20181026151315-13cfe3978170
 	k8s.io/client-go v8.0.0+incompatible
 	k8s.io/code-generator v0.0.0-20181203235156-f8cba74510f3
-	k8s.io/gengo v0.0.0-20181106084056-51747d6e00da // indirect
-	k8s.io/klog v0.0.0-20181102134211-b9b56d5dfc92 // indirect
+	k8s.io/gengo v0.0.0-20181113154421-fd15ee9cc2f7 // indirect
+	k8s.io/klog v0.1.0 // indirect
 	k8s.io/kube-aggregator v0.0.0-20181204002017-122bac39d429
 	k8s.io/kube-openapi v0.0.0-20181031203759-72693cb1fadd
-	k8s.io/kubernetes v1.11.7-beta.0.0.20181219023948-b875d52ea96d
+	k8s.io/kubernetes v1.11.7-beta.0.0.20190105100524-8bc0774147c7
 )