feat: add essential data structures for service subset selector (#489)

pkg/kube/apisix/apis/config/v1/types.go

@@ -119,6 +119,18 @@ type ApisixUpstreamConfig struct {
 	// The health check configurations for the upstream.
 	// +optional
 	HealthCheck *HealthCheck `json:"healthCheck,omitempty" yaml:"healthCheck,omitempty"`
+	// Subsets groups the service endpoints by their labels. Usually used to differentiate
+	// service versions.
+	// +optional
+	Subsets []ApisixUpstreamSubset `json:"subsets,omitempty" yaml:"subsets,omitempty"`
+}
+
+// ApisixUpstreamSubset defines a single endpoints group of one Service.
+type ApisixUpstreamSubset struct {
+	// Name is the name of subset.
+	Name string `json:"name" yaml:"name"`
+	// Labels is the label set of this subset.
+	Labels map[string]string `json:"labels" yaml:"labels"`
 }
 
 // UpstreamTimeout is settings for the read, send and connect to the upstream.

pkg/kube/apisix/apis/config/v2alpha1/types.go

@@ -129,7 +129,7 @@ type ApisixRouteHTTPMatch struct {
 	NginxVars []ApisixRouteHTTPMatchExpr `json:"exprs,omitempty" yaml:"exprs,omitempty"`
 }
 
-// ApisixRouteHTTPMatchExpre represents a binary route match expression .
+// ApisixRouteHTTPMatchExpr represents a binary route match expression .
 type ApisixRouteHTTPMatchExpr struct {
 	// Subject is the expression subject, it can
 	// be any string composed by literals and nginx

pkg/types/labels.go

@@ -0,0 +1,33 @@
+// Licensed to the Apache Software Foundation (ASF) under one or more
+// contributor license agreements.  See the NOTICE file distributed with
+// this work for additional information regarding copyright ownership.
+// The ASF licenses this file to You under the Apache License, Version 2.0
+// (the "License"); you may not use this file except in compliance with
+// the License.  You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+package types
+
+// Labels contains a series of labels.
+type Labels map[string]string
+
+// IsSubsetOf checks whether the current Labels is the subset of
+// the passed Labels.
+func (s Labels) IsSubsetOf(f Labels) bool {
+	if len(s) == 0 {
+		// Empty labels matches nothing not everything.
+		return false
+	}
+	for k, v := range s {
+		if vv, ok := f[k]; !ok || vv != v {
+			return false
+		}
+	}
+	return true
+}

pkg/types/labels_test.go

@@ -0,0 +1,34 @@
+// Licensed to the Apache Software Foundation (ASF) under one or more
+// contributor license agreements.  See the NOTICE file distributed with
+// this work for additional information regarding copyright ownership.
+// The ASF licenses this file to You under the Apache License, Version 2.0
+// (the "License"); you may not use this file except in compliance with
+// the License.  You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+package types
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestLabelsIsSubsetOf(t *testing.T) {
+	l := Labels{}
+	f := Labels{
+		"version": "v1",
+		"env":     "prod",
+	}
+	assert.Equal(t, l.IsSubsetOf(f), false)
+	l["env"] = "prod"
+	assert.Equal(t, l.IsSubsetOf(f), true)
+	l["env"] = "qa"
+	assert.Equal(t, l.IsSubsetOf(f), false)
+}

samples/deploy/crd/v1beta1/ApisixUpstream.yaml

@@ -40,6 +40,17 @@ spec:
         spec:
           type: object
           properties:
+            subsets:
+              type: array
+              items:
+                type: object
+                properties:
+                  name:
+                    type: string
+                    minLength: 1
+                  labels:
+                    type: object
+                required: ["name", "labels"]
             loadbalancer:
               type: object
               properties: