Added UUID random generation

src/libs/utils/impl/UUID.cpp

@@ -19,40 +19,71 @@
 
 #include "utils/UUID.hpp"
 
+#include <cassert>
+#include <iomanip>
 #include <regex>
+#include <sstream>
 
+#include "utils/Random.hpp"
 #include "utils/String.hpp"
 
 namespace StringUtils
 {
-	template <>
-	std::optional<UUID>
-	readAs(std::string_view str)
-	{
-		return UUID::fromString(str);
-	}
+    template <>
+    std::optional<UUID>
+        readAs(std::string_view str)
+    {
+        return UUID::fromString(str);
+    }
 }
-
-static
-bool
-stringIsUUID(std::string_view str)
+namespace
 {
-	static const std::regex re { R"([0-9a-fA-F]{8}\-[0-9a-fA-F]{4}\-[0-9a-fA-F]{4}\-[0-9a-fA-F]{4}\-[0-9a-fA-F]{12})"};
+    bool stringIsUUID(std::string_view str)
+    {
+        static const std::regex re{ R"([0-9a-fA-F]{8}\-[0-9a-fA-F]{4}\-[0-9a-fA-F]{4}\-[0-9a-fA-F]{4}\-[0-9a-fA-F]{12})" };
 
-	return std::regex_match(std::cbegin(str), std::cend(str), re);
+        return std::regex_match(std::cbegin(str), std::cend(str), re);
+    }
 }
 
 UUID::UUID(std::string_view str)
-	: _value {StringUtils::stringToLower(str)}
+    : _value{ StringUtils::stringToLower(str) }
 {
 }
 
-std::optional<UUID>
-UUID::fromString(std::string_view str)
+std::optional<UUID> UUID::fromString(std::string_view str)
 {
-	if (!stringIsUUID(str))
-		return std::nullopt;
+    if (!stringIsUUID(str))
+        return std::nullopt;
 
-	return UUID {str};
+    return UUID{ str };
+}
+
+UUID UUID::generate()
+{
+    // Form is "123e4567-e89b-12d3-a456-426614174000"
+    // TODO: store 128 bits and only convert to string when necessary
+
+    std::ostringstream oss;
+
+    auto concatRandomBytes{ [](std::ostream& os, std::size_t byteCount)
+    {
+        for (std::size_t i {}; i < byteCount; ++i)
+            os << std::hex << std::setfill('0') << std::setw(2) << static_cast<int>(Random::getRandom<std::uint8_t>(0, 255));
+    } };
+
+    concatRandomBytes(oss, 4);
+    oss << "-";
+    concatRandomBytes(oss, 2);
+    oss << "-";
+    concatRandomBytes(oss, 2);
+    oss << "-";
+    concatRandomBytes(oss, 2);
+    oss << "-";
+    concatRandomBytes(oss, 6);
+
+    const auto uuid{fromString(oss.str())};
+    assert(uuid);
+    return uuid.value();
 }
 

src/libs/utils/include/utils/UUID.hpp

@@ -27,20 +27,21 @@
 
 class UUID
 {
-	public:
-		static std::optional<UUID> fromString(std::string_view str);
+public:
+    static std::optional<UUID> fromString(std::string_view str);
+    static UUID generate();
 
-		std::string_view getAsString() const { return _value; }
+    std::string_view getAsString() const { return _value; }
 
-	private:
-		UUID(std::string_view value);
-		std::string _value;
+private:
+    UUID(std::string_view value);
+    std::string _value;
 };
 
 namespace StringUtils
 {
-	template <>
-	std::optional<UUID>
-	readAs(std::string_view str);
+    template <>
+    std::optional<UUID>
+        readAs(std::string_view str);
 }