Add REST API using grpc gateway

Gopkg.toml

@@ -13,6 +13,9 @@ required = [
     "sigs.k8s.io/controller-runtime/pkg/source",
     "sigs.k8s.io/testing_frameworks/integration", # for integration testing
 	"k8s.io/apiextensions-apiserver/pkg/apis/apiextensions/v1beta1",
+    "github.com/grpc-ecosystem/grpc-gateway/protoc-gen-grpc-gateway",
+    "github.com/grpc-ecosystem/grpc-gateway/protoc-gen-swagger",
+    "github.com/golang/protobuf/protoc-gen-go",
     ]
 
 [prune]

cmd/manager-rest/Dockerfile

@@ -0,0 +1,10 @@
+FROM golang:alpine AS build-env
+# The GOPATH in the image is /go.
+ADD . /go/src/github.com/kubeflow/katib
+WORKDIR /go/src/github.com/kubeflow/katib/cmd/manager-rest
+RUN go build -o vizier-manager-rest
+
+FROM alpine:3.7
+WORKDIR /app
+COPY --from=build-env /go/src/github.com/kubeflow/katib/cmd/manager-rest/vizier-manager-rest /app/
+ENTRYPOINT ["./vizier-manager-rest"]

cmd/manager-rest/proxy.go

@@ -0,0 +1,43 @@
+package main
+
+import (
+  "flag"
+  "net/http"
+
+  "github.com/golang/glog"
+  "golang.org/x/net/context"
+  "github.com/grpc-ecosystem/grpc-gateway/runtime"
+  "google.golang.org/grpc"
+
+  gw "github.com/kubeflow/katib/pkg/api"
+)
+
+var (
+  vizierCoreEndpoint = flag.String("echo_endpoint", "vizier-core:6789", "vizier-core endpoint")
+)
+
+func run() error {
+  ctx := context.Background()
+  ctx, cancel := context.WithCancel(ctx)
+  defer cancel()
+
+  mux := runtime.NewServeMux()
+  opts := []grpc.DialOption{grpc.WithInsecure()}
+  // register handlers for the HTTP endpoints
+  err := gw.RegisterManagerHandlerFromEndpoint(ctx, mux, *vizierCoreEndpoint, opts)
+  if err != nil {
+    return err
+  }
+
+  // proxy server listens on port 80
+  return http.ListenAndServe(":80", mux)
+}
+
+func main() {
+  flag.Parse()
+  defer glog.Flush()
+
+  if err := run(); err != nil {
+    glog.Fatal(err)
+  }
+}

docs/rest-api.md

@@ -0,0 +1,77 @@
+## REST API 
+
+For each RPC service, we define an equivalent HTTP REST API method using [grpc-gateway](https://github.com/grpc-ecosystem/grpc-gateway). The mapping between service and REST API method can be found in this [file](https://github.com/kubeflow/katib/blob/master/pkg/api/api.proto). The mapping includes the URL path, query parameters and request body. You can read more details on the supported methods and binding options at this [link](https://cloud.google.com/service-infrastructure/docs/service-management/reference/rpc/google.api#http)
+
+## Examples
+Assuming `{HOST}` as the ingress host for vizier-core-rest, 
+
+### Create a new Study
+
+Sample JSON file (study_config.json)
+
+```json
+{
+	"name": "study1",
+	"owner": "mayankjuneja",
+	"optimization_type": 2,
+	"optimization_goal": null,
+	"parameter_configs": {
+		"configs": [{
+			"name": "dropout",
+			"parameter_type": 1,
+			"feasible": {
+				"max": "0.5",
+				"min": "0.1",
+				"list": []
+			}
+		}, {
+			"name": "activation",
+			"parameter_type": 4,
+			"feasible": {
+				"max": "0",
+				"min": "0",
+				"list": ["tanh", "relu"]
+			}
+		}]
+	},
+	"objective_value_name": "accuracy"
+}
+```
+
+Request:
+
+```shell
+curl -X POST {HOST}/api/Manager/CreateStudy
+```
+
+Response:
+
+```json
+{"study_id": "k350afb1ad0e580e"}
+```
+
+### Get List of Studies
+
+Request:
+```shell
+curl -X GET {HOST}/api/Manager/GetStudyList
+```
+
+Response:
+```json
+{
+  "study_overviews": [
+    {
+      "name": "study1",
+      "owner": "mayankjuneja",
+      "id": "k350afb1ad0e580e"
+    },
+    {
+      "name": "study2",
+      "owner": "mayankjuneja",
+      "id": "pae3c470c9584cc4"
+    }
+  ]
+}
+```
+

manifests/vizier/core-rest/deployment.yaml

@@ -0,0 +1,33 @@
+apiVersion: extensions/v1beta1
+kind: Deployment
+metadata:
+  name: vizier-core-rest
+  namespace: katib
+  labels:
+    app: vizier
+    component: core-rest
+spec:
+  replicas: 1
+  template:
+    metadata:
+      name: vizier-core-rest
+      labels:
+        app: vizier
+        component: core-rest
+    spec:
+      serviceAccountName: vizier-core-rest
+      containers:
+      - name: vizier-core-rest
+        image: katib/vizier-core-rest
+        command:
+          - './vizier-manager-rest'
+        ports:
+        - name: api
+          containerPort: 80
+#        resources:
+#          requests:
+#            cpu: 500m
+#            memory: 500M
+#          limits:
+#            cpu: 500m
+#            memory: 500M

manifests/vizier/core-rest/ingress.yaml_

@@ -0,0 +1,16 @@
+apiVersion: extensions/v1beta1
+kind: Ingress
+metadata:
+  name: vizier-core-rest
+  namespace: katib
+  annotations:
+    ingress.kubernetes.io/rewrite-target: /
+spec:
+  rules:
+  - host: vizier-core-rest.k-cluster.example.net
+    http:
+      paths:
+      - path: /
+        backend:
+          serviceName: vizier-core-rest
+          servicePort: 80

manifests/vizier/core-rest/rbac.yaml

@@ -0,0 +1,37 @@
+---
+apiVersion: rbac.authorization.k8s.io/v1beta1
+kind: ClusterRoleBinding
+metadata:
+  name: vizier-core-rest
+roleRef:
+  apiGroup: rbac.authorization.k8s.io
+  kind: ClusterRole
+  name: vizier-core-rest
+subjects:
+- kind: ServiceAccount
+  name: vizier-core-rest
+  namespace: katib
+---
+kind: ClusterRole
+apiVersion: rbac.authorization.k8s.io/v1beta1
+metadata:
+  name: vizier-core-rest
+rules:
+  - apiGroups: [""] 
+    resources: ["pods", "nodes", "nodes/*", "pods/log", "pods/status", "services", "persistentvolumes", "persistentvolumes/status","persistentvolumeclaims","persistentvolumeclaims/status"] 
+    verbs: ["*"]
+  - apiGroups: ["batch"] 
+    resources: ["jobs", "jobs/status"] 
+    verbs: ["*"]
+  - apiGroups: ["extensions"] 
+    verbs: ["*"]
+    resources: ["ingresses","ingresses/status","deployments","deployments/status"] 
+  - apiGroups: [""] 
+    verbs: ["*"]
+    resources: ["services"] 
+---
+apiVersion: v1
+kind: ServiceAccount
+metadata:
+  name: vizier-core-rest
+  namespace: katib

manifests/vizier/core-rest/service.yaml

@@ -0,0 +1,17 @@
+apiVersion: v1
+kind: Service
+metadata:
+  name: vizier-core-rest
+  namespace: katib
+  labels:
+    app: vizier
+    component: core-rest
+spec:
+  type: ClusterIP
+  ports:
+    - port: 80
+      protocol: TCP
+      name: api
+  selector:
+    app: vizier
+    component: core-rest