fix: Add overlap status for duplicate HTTPRoutes

internal/gatewayapi/overlap_test.go

@@ -0,0 +1,286 @@
+// Copyright Envoy Gateway Authors
+// SPDX-License-Identifier: Apache-2.0
+// The full text of the Apache license is available in the LICENSE file at
+// the root of the repo.
+
+package gatewayapi
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"k8s.io/utils/ptr"
+
+	"github.com/envoyproxy/gateway/internal/ir"
+)
+
+func TestRouteMatchesOverlap(t *testing.T) {
+	tests := []struct {
+		name    string
+		a       *ir.HTTPRoute
+		b       *ir.HTTPRoute
+		overlap bool
+	}{
+		{
+			name: "identical exact path and hostname",
+			a: &ir.HTTPRoute{
+				Hostname:  "example.com",
+				PathMatch: &ir.StringMatch{Exact: ptr.To("/foo")},
+			},
+			b: &ir.HTTPRoute{
+				Hostname:  "example.com",
+				PathMatch: &ir.StringMatch{Exact: ptr.To("/foo")},
+			},
+			overlap: true,
+		},
+		{
+			name: "different exact paths",
+			a: &ir.HTTPRoute{
+				Hostname:  "example.com",
+				PathMatch: &ir.StringMatch{Exact: ptr.To("/foo")},
+			},
+			b: &ir.HTTPRoute{
+				Hostname:  "example.com",
+				PathMatch: &ir.StringMatch{Exact: ptr.To("/bar")},
+			},
+			overlap: false,
+		},
+		{
+			name: "different hostnames",
+			a: &ir.HTTPRoute{
+				Hostname:  "a.example.com",
+				PathMatch: &ir.StringMatch{Exact: ptr.To("/foo")},
+			},
+			b: &ir.HTTPRoute{
+				Hostname:  "b.example.com",
+				PathMatch: &ir.StringMatch{Exact: ptr.To("/foo")},
+			},
+			overlap: false,
+		},
+		{
+			name: "prefix paths are not detected as overlap",
+			a: &ir.HTTPRoute{
+				Hostname:  "example.com",
+				PathMatch: &ir.StringMatch{Prefix: ptr.To("/api")},
+			},
+			b: &ir.HTTPRoute{
+				Hostname:  "example.com",
+				PathMatch: &ir.StringMatch{Prefix: ptr.To("/api")},
+			},
+			overlap: false,
+		},
+		{
+			name: "nil path matches are not detected as overlap",
+			a: &ir.HTTPRoute{
+				Hostname: "example.com",
+			},
+			b: &ir.HTTPRoute{
+				Hostname: "example.com",
+			},
+			overlap: false,
+		},
+		{
+			name: "exact vs prefix same value not overlap",
+			a: &ir.HTTPRoute{
+				Hostname:  "example.com",
+				PathMatch: &ir.StringMatch{Exact: ptr.To("/foo")},
+			},
+			b: &ir.HTTPRoute{
+				Hostname:  "example.com",
+				PathMatch: &ir.StringMatch{Prefix: ptr.To("/foo")},
+			},
+			overlap: false,
+		},
+		{
+			name: "identical exact path with identical header matches",
+			a: &ir.HTTPRoute{
+				Hostname:  "example.com",
+				PathMatch: &ir.StringMatch{Exact: ptr.To("/foo")},
+				HeaderMatches: []*ir.StringMatch{
+					{Name: "X-Custom", Exact: ptr.To("val1")},
+				},
+			},
+			b: &ir.HTTPRoute{
+				Hostname:  "example.com",
+				PathMatch: &ir.StringMatch{Exact: ptr.To("/foo")},
+				HeaderMatches: []*ir.StringMatch{
+					{Name: "X-Custom", Exact: ptr.To("val1")},
+				},
+			},
+			overlap: true,
+		},
+		{
+			name: "identical exact path with different header matches",
+			a: &ir.HTTPRoute{
+				Hostname:  "example.com",
+				PathMatch: &ir.StringMatch{Exact: ptr.To("/foo")},
+				HeaderMatches: []*ir.StringMatch{
+					{Name: "X-Custom", Exact: ptr.To("val1")},
+				},
+			},
+			b: &ir.HTTPRoute{
+				Hostname:  "example.com",
+				PathMatch: &ir.StringMatch{Exact: ptr.To("/foo")},
+				HeaderMatches: []*ir.StringMatch{
+					{Name: "X-Custom", Exact: ptr.To("val2")},
+				},
+			},
+			overlap: false,
+		},
+		{
+			name: "identical exact path one has headers other does not",
+			a: &ir.HTTPRoute{
+				Hostname:  "example.com",
+				PathMatch: &ir.StringMatch{Exact: ptr.To("/foo")},
+				HeaderMatches: []*ir.StringMatch{
+					{Name: "X-Custom", Exact: ptr.To("val1")},
+				},
+			},
+			b: &ir.HTTPRoute{
+				Hostname:  "example.com",
+				PathMatch: &ir.StringMatch{Exact: ptr.To("/foo")},
+			},
+			overlap: false,
+		},
+		{
+			name: "identical exact path with identical query param matches",
+			a: &ir.HTTPRoute{
+				Hostname:  "example.com",
+				PathMatch: &ir.StringMatch{Exact: ptr.To("/foo")},
+				QueryParamMatches: []*ir.StringMatch{
+					{Name: "key", Exact: ptr.To("value")},
+				},
+			},
+			b: &ir.HTTPRoute{
+				Hostname:  "example.com",
+				PathMatch: &ir.StringMatch{Exact: ptr.To("/foo")},
+				QueryParamMatches: []*ir.StringMatch{
+					{Name: "key", Exact: ptr.To("value")},
+				},
+			},
+			overlap: true,
+		},
+		{
+			name: "regex path matches are not detected as overlap",
+			a: &ir.HTTPRoute{
+				Hostname:  "example.com",
+				PathMatch: &ir.StringMatch{SafeRegex: ptr.To("/foo.*")},
+			},
+			b: &ir.HTTPRoute{
+				Hostname:  "example.com",
+				PathMatch: &ir.StringMatch{SafeRegex: ptr.To("/foo.*")},
+			},
+			overlap: false,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			assert.Equal(t, tt.overlap, routeMatchesOverlap(tt.a, tt.b))
+		})
+	}
+}
+
+func TestStringMatchEqual(t *testing.T) {
+	tests := []struct {
+		name  string
+		a     *ir.StringMatch
+		b     *ir.StringMatch
+		equal bool
+	}{
+		{
+			name:  "both nil",
+			a:     nil,
+			b:     nil,
+			equal: true,
+		},
+		{
+			name:  "one nil",
+			a:     &ir.StringMatch{Exact: ptr.To("foo")},
+			b:     nil,
+			equal: false,
+		},
+		{
+			name:  "identical exact",
+			a:     &ir.StringMatch{Name: "h", Exact: ptr.To("v")},
+			b:     &ir.StringMatch{Name: "h", Exact: ptr.To("v")},
+			equal: true,
+		},
+		{
+			name:  "different name",
+			a:     &ir.StringMatch{Name: "a", Exact: ptr.To("v")},
+			b:     &ir.StringMatch{Name: "b", Exact: ptr.To("v")},
+			equal: false,
+		},
+		{
+			name:  "different value",
+			a:     &ir.StringMatch{Name: "h", Exact: ptr.To("v1")},
+			b:     &ir.StringMatch{Name: "h", Exact: ptr.To("v2")},
+			equal: false,
+		},
+		{
+			name:  "different distinct",
+			a:     &ir.StringMatch{Name: "h", Distinct: true},
+			b:     &ir.StringMatch{Name: "h", Distinct: false},
+			equal: false,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			assert.Equal(t, tt.equal, stringMatchEqual(tt.a, tt.b))
+		})
+	}
+}
+
+func TestStringMatchSliceEqual(t *testing.T) {
+	tests := []struct {
+		name  string
+		a     []*ir.StringMatch
+		b     []*ir.StringMatch
+		equal bool
+	}{
+		{
+			name:  "both empty",
+			a:     nil,
+			b:     nil,
+			equal: true,
+		},
+		{
+			name:  "different lengths",
+			a:     []*ir.StringMatch{{Name: "a", Exact: ptr.To("1")}},
+			b:     nil,
+			equal: false,
+		},
+		{
+			name: "identical",
+			a: []*ir.StringMatch{
+				{Name: "a", Exact: ptr.To("1")},
+				{Name: "b", Exact: ptr.To("2")},
+			},
+			b: []*ir.StringMatch{
+				{Name: "a", Exact: ptr.To("1")},
+				{Name: "b", Exact: ptr.To("2")},
+			},
+			equal: true,
+		},
+		{
+			name: "same elements different order",
+			a: []*ir.StringMatch{
+				{Name: "a", Exact: ptr.To("1")},
+				{Name: "b", Exact: ptr.To("2")},
+			},
+			b: []*ir.StringMatch{
+				{Name: "b", Exact: ptr.To("2")},
+				{Name: "a", Exact: ptr.To("1")},
+			},
+			equal: false,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			assert.Equal(t, tt.equal, stringMatchSliceEqual(tt.a, tt.b))
+		})
+	}
+}