feat: add helper function to handle cim IP Addresses

parsing/cim_ip_address.go

@@ -0,0 +1,35 @@
+package parsing
+
+import (
+	"encoding/json"
+	"fmt"
+	"net/netip"
+)
+
+// CimIpAddress represents an IP Address value.
+type CimIpAddress netip.Addr
+
+// UnmarshalJSON implements the json.Unmarshaler interface for the CimIpAddress type.
+func (a *CimIpAddress) UnmarshalJSON(b []byte) error {
+	// Parse the integer from the JSON input
+	var addr uint32
+	if err := json.Unmarshal(b, &addr); err != nil {
+		return fmt.Errorf("parsing.UnmarshalJSON(CimIpAddress): failed to parse IP address from JSON: %w", err)
+	}
+
+	// Convert integer to IPv4 address
+	ip := [4]byte{
+		byte(addr),
+		byte(addr >> 8),
+		byte(addr >> 16),
+		byte(addr >> 24),
+	}
+
+	// Use netip to create the address
+	parsedAddr := netip.AddrFrom4(ip)
+
+	// Assign the parsed address to the pointer receiver
+	*a = CimIpAddress(parsedAddr)
+
+	return nil
+}

parsing/cim_ip_address_test.go

@@ -0,0 +1,59 @@
+package parsing
+
+import (
+	"encoding/json"
+	"net/netip"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestCimIpAddressUnmarshalJSON(t *testing.T) {
+	t.Parallel()
+
+	t.Run("ValidIPv4Address", func(t *testing.T) {
+		// Valid integer representation of 10.100.91.51
+		jsonData := `861627402`
+		var ip CimIpAddress
+
+		err := json.Unmarshal([]byte(jsonData), &ip)
+		require.NoError(t, err)
+
+		expectedIP := netip.MustParseAddr("10.100.91.51")
+		assert.Equal(t, expectedIP, netip.Addr(ip))
+	})
+
+	t.Run("InvalidJSONFormat", func(t *testing.T) {
+		// Invalid JSON (string instead of integer)
+		jsonData := `"notAnInteger"`
+		var ip CimIpAddress
+
+		err := json.Unmarshal([]byte(jsonData), &ip)
+		assert.Error(t, err)
+	})
+
+	t.Run("ZeroAddress", func(t *testing.T) {
+		// Test edge case with 0
+		jsonData := `0`
+		var ip CimIpAddress
+
+		err := json.Unmarshal([]byte(jsonData), &ip)
+		require.NoError(t, err)
+
+		expectedIP := netip.MustParseAddr("0.0.0.0")
+		assert.Equal(t, expectedIP, netip.Addr(ip))
+	})
+
+	t.Run("MaxIPv4Address", func(t *testing.T) {
+		// Test edge case with maximum IPv4 address (255.255.255.255)
+		jsonData := `4294967295` // Equivalent to 255.255.255.255
+		var ip CimIpAddress
+
+		err := json.Unmarshal([]byte(jsonData), &ip)
+		require.NoError(t, err)
+
+		expectedIP := netip.MustParseAddr("255.255.255.255")
+		assert.Equal(t, expectedIP, netip.Addr(ip))
+	})
+}