feat: Add localhost IP range (main)

Adds a new IP range fetcher for localhost, useful for
development and testing.  Includes updates to the
generated data, tests, and documentation

Author: JasonLovesDoggo

Diff for: README.md

@@ -130,11 +130,13 @@ localhost:8082 {
 
 The plugin includes predefined IP ranges for popular AI services. These ranges are embedded in the binary and can be used without additional configuration.
 
-| Service         | IP Ranges                                  |
-|-----------------|--------------------------------------------|
-| OpenAI          | [openai.go](ranges/fetchers/openai.go)     |
-| DeepSeek        | [deepseek.go](ranges/fetchers/deepseek.go) |
-| GitHub Copilot  | [github.go](ranges/fetchers/github.go)     |
+| Service             | IP Ranges                                    |
+|---------------------|----------------------------------------------|
+| OpenAI              | [openai.go](ranges/fetchers/openai.go)       |
+| DeepSeek            | [deepseek.go](ranges/fetchers/deepseek.go)   |
+| GitHub Copilot      | [github.go](ranges/fetchers/github.go)       |
+| Microsoft Azure     | [azure.go](ranges/fetchers/azure.go)         |
+| Localhost (testing) | [localhost.go](ranges/fetchers/localhost.go) |
 
 More are welcome! for a precompiled list, see the [embedded results](ranges/data/generated.go)
 

Diff for: ranges/data/generated.go

@@ -0,0 +1,18 @@
+package fetchers
+
+// LocalhostFetcher implements the IPRangeFetcher interface for Localhost.
+type LocalhostFetcher struct{}
+
+func (f LocalhostFetcher) Name() string {
+	return "Localhost"
+}
+func (f LocalhostFetcher) Description() string {
+	return "Hardcoded IP ranges for Localhost. Used in development."
+}
+func (f LocalhostFetcher) FetchIPRanges() ([]string, error) {
+
+	return []string{
+		"127.0.0.0/8", // IPv4 localhost range
+		"::1/128",     // IPv6 localhost range
+	}, nil
+}

Diff for: ranges/fetchers/localhost.go

@@ -29,6 +29,7 @@ func main() {
 		fetchers.DeepSeekFetcher{},
 		fetchers.GithubCopilotFetcher{},
 		fetchers.AzurePublicCloudFetcher{},
+		fetchers.LocalhostFetcher{},
 	}
 
 	// Create a map to hold the IP ranges

Diff for: ranges/main.go

@@ -33,8 +33,21 @@ var (
 // Mock logger for testing
 var testLogger = zap.NewNop()
 
-// TestRawIPInRanges tests the rawIPInRanges function.
 func TestRawIPInRanges(t *testing.T) {
+	// Mock predefined CIDRs
+	originalIPRanges := data.IPRanges
+
+	// Restore the original data.IPRanges map after the test
+	defer func() {
+		data.IPRanges = originalIPRanges
+	}()
+	data.IPRanges = map[string][]string{
+		"openai": {
+			"203.0.113.0/24",
+			"2001:db8:1::/48",
+		},
+	}
+
 	tests := []struct {
 		name       string
 		ip         string
@@ -90,9 +103,6 @@ func TestRawIPInRanges(t *testing.T) {
 			clientIP := net.ParseIP(tt.ip)
 			assert.NotNil(t, clientIP, "Failed to parse IP")
 
-			// Mock predefined CIDRs
-			data.IPRanges = predefinedCIDRs
-
 			result := rawIPInRanges(clientIP, tt.cidrRanges, testLogger)
 			assert.Equal(t, tt.expected, result, "Unexpected result for IP %s", tt.ip)
 		})
@@ -126,9 +136,6 @@ func TestIPInRanges(t *testing.T) {
 			clientIP := net.ParseIP(tt.ip)
 			assert.NotNil(t, clientIP, "Failed to parse IP")
 
-			// Mock predefined CIDRs
-			data.IPRanges = predefinedCIDRs
-
 			// First call (not cached)
 			result := IPInRanges(clientIP, tt.cidrRanges, testLogger)
 			assert.Equal(t, tt.expected, result, "Unexpected result for IP %s (first call)", tt.ip)
@@ -148,9 +155,6 @@ func TestIPInRangesCacheExpiration(t *testing.T) {
 	clientIP := net.ParseIP("192.168.1.100")
 	assert.NotNil(t, clientIP, "Failed to parse IP")
 
-	// Mock predefined CIDRs
-	data.IPRanges = predefinedCIDRs
-
 	// First call (not cached)
 	result := IPInRanges(clientIP, validCIDRs, testLogger)
 	assert.True(t, result, "Expected IP to be in range (first call)")
@@ -162,3 +166,57 @@ func TestIPInRangesCacheExpiration(t *testing.T) {
 	result = IPInRanges(clientIP, validCIDRs, testLogger)
 	assert.True(t, result, "Expected IP to be in range (second call, cache expired)")
 }
+
+func TestLocalhostRanges(t *testing.T) {
+	// Mock the data.IPRanges map to include the "localhost" range
+	originalIPRanges := data.IPRanges
+
+	// Restore the original data.IPRanges map after the test
+	defer func() {
+		data.IPRanges = originalIPRanges
+	}()
+	data.IPRanges = map[string][]string{
+		"localhost": {
+			"127.0.0.0/8", // IPv4 localhost range
+			"::1/128",     // IPv6 localhost range
+		},
+	}
+
+	tests := []struct {
+		name     string
+		ip       string
+		expected bool
+	}{
+		{
+			name:     "IPv4 localhost",
+			ip:       "127.0.0.1",
+			expected: true,
+		},
+		{
+			name:     "IPv4 non-localhost",
+			ip:       "192.168.1.1",
+			expected: false,
+		},
+		{
+			name:     "IPv6 localhost",
+			ip:       "::1",
+			expected: true,
+		},
+		{
+			name:     "IPv6 non-localhost",
+			ip:       "2001:db8::1",
+			expected: false,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			clientIP := net.ParseIP(tt.ip)
+			assert.NotNil(t, clientIP, "Failed to parse IP")
+
+			// Pass "localhost" as the CIDR range to check
+			result := rawIPInRanges(clientIP, []string{"localhost"}, testLogger)
+			assert.Equal(t, tt.expected, result, "Unexpected result for IP %s", tt.ip)
+		})
+	}
+}