add PostgresINET type

Author: rausnitz

Sources/PostgresNIO/New/Data/PostgresINET+PostgresCodable.swift

@@ -0,0 +1,66 @@
+public struct PostgresINET {
+    public let ipFamily: UInt8
+    public let netmaskLength: UInt8
+    public let isCIDR: Bool
+    public let addressLength: UInt8
+    public let ipAddress: [UInt8]
+}
+
+extension PostgresINET: PostgresDecodable {
+    public init<JSONDecoder: PostgresJSONDecoder>(from byteBuffer: inout ByteBuffer, type: PostgresDataType, format: PostgresFormat, context: PostgresDecodingContext<JSONDecoder>) throws {
+        // IP family
+        guard let ipFamily: UInt8 = byteBuffer.readInteger(as: UInt8.self) else {
+            throw PostgresDecodingError.Code.failure
+        }
+
+        // netmask length in bits
+        guard let netmaskLength: UInt8 = byteBuffer.readInteger(as: UInt8.self) else {
+            throw PostgresDecodingError.Code.failure
+        }
+
+        // whether it is a CIDR
+        let isCIDR: Bool
+        switch byteBuffer.readInteger(as: UInt8.self) {
+        case .some(0):
+            isCIDR = false
+        case .some(1):
+            isCIDR = true
+        default:
+            throw PostgresDecodingError.Code.failure
+        }
+
+        // address length in bytes
+        guard let addressLength: UInt8 = byteBuffer.readInteger(as: UInt8.self),
+            addressLength * 8 == netmaskLength,
+            let ipAddress: [UInt8] = byteBuffer.readBytes(length: Int(addressLength))
+        else {
+            throw PostgresDecodingError.Code.failure
+        }
+
+        self.init(
+            ipFamily: ipFamily,
+            netmaskLength: netmaskLength,
+            isCIDR: isCIDR,
+            addressLength: addressLength,
+            ipAddress: ipAddress
+        )
+    }
+}
+
+extension PostgresINET: PostgresEncodable & PostgresNonThrowingEncodable {
+    public static var psqlType: PostgresDataType { return .inet }
+    public static var psqlFormat: PostgresFormat { .binary }
+    public func encode<JSONEncoder: PostgresJSONEncoder>(into byteBuffer: inout ByteBuffer, context: PostgresEncodingContext<JSONEncoder>) {
+        byteBuffer.writeInteger(self.ipFamily, as: UInt8.self)
+        byteBuffer.writeInteger(self.netmaskLength, as: UInt8.self)
+        byteBuffer.writeInteger(self.isCIDR ? 1 : 0, as: UInt8.self)
+        byteBuffer.writeInteger(self.addressLength, as: UInt8.self)
+        byteBuffer.writeBytes(self.ipAddress)
+    }
+}
+
+extension PostgresINET: PostgresArrayDecodable {}
+
+extension PostgresINET: PostgresArrayEncodable {
+    public static var psqlArrayType: PostgresDataType { return .inetArray }
+}