TLS/SSL Support in Glaze HTTP Server¶

Glaze supports TLS/SSL encryption for HTTPS servers through a template-based approach that provides zero overhead for HTTP-only applications.

Overview¶

The http_server has been enhanced with a template parameter <bool EnableTLS> that allows you to create both HTTP and HTTPS servers:

http_server<false> or http_server<> - Standard HTTP server (default)
http_server<true> or https_server - HTTPS server with TLS support

Building with TLS Support¶

Prerequisites¶

OpenSSL development libraries
CMake 3.21 or later
C++23 compatible compiler

CMake Configuration¶

Enable TLS support when configuring your build:

cmake -Dglaze_ENABLE_SSL=ON ..

This will: - Find and link OpenSSL libraries - Define GLZ_ENABLE_SSL preprocessor macro - Enable TLS functionality in the http_server template

Usage¶

Basic HTTPS Server¶

#include "glaze/net/http_server.hpp"

int main() {
    // Create HTTPS server using alias
    glz::https_server server;

    // Load SSL certificate and private key
    server.load_certificate("path/to/cert.pem", "path/to/private_key.pem");

    // Configure routes
    server.get("/", [](const glz::request& req, glz::response& res) {
        res.body("Hello, HTTPS World!");
    });

    // Start server on port 8443
    server.bind(8443).start();

    return 0;
}

Using Template Parameter¶

// Explicit template parameter
glz::http_server<true> https_server;
glz::http_server<false> http_server;  // or just http_server<>

SSL Configuration¶

glz::https_server server;

// Load certificate and key
server.load_certificate("cert.pem", "key.pem");

// Set SSL verification mode (optional)
server.set_ssl_verify_mode(SSL_VERIFY_NONE);  // For development
// server.set_ssl_verify_mode(SSL_VERIFY_PEER);  // For production

Certificate Generation¶

For development and testing, you can generate self-signed certificates:

# Generate private key
openssl genrsa -out key.pem 2048

# Generate self-signed certificate
openssl req -new -x509 -key key.pem -out cert.pem -days 365

API Reference¶

Template Parameters¶

EnableTLS (bool): Enable TLS support
false (default): HTTP server
true: HTTPS server

Type Aliases¶

https_server: Alias for http_server<true>

HTTPS-Specific Methods¶

`load_certificate(cert_file, key_file)`¶

Load SSL certificate and private key files (PEM format).

server.load_certificate("path/to/cert.pem", "path/to/key.pem");

`set_ssl_verify_mode(mode)`¶

Set SSL peer verification mode.

server.set_ssl_verify_mode(SSL_VERIFY_NONE);    // No verification
server.set_ssl_verify_mode(SSL_VERIFY_PEER);    // Verify peer certificate

Design Benefits¶

Zero Overhead for HTTP¶

HTTP servers (EnableTLS = false) have no TLS-related code or memory overhead
SSL headers and context are only included when EnableTLS = true
Compile-time optimization ensures maximum performance

Type Safety¶

Template parameter provides compile-time differentiation
Prevents accidental mixing of HTTP and HTTPS configurations
Clear API distinction between server types

Backward Compatibility¶

Existing HTTP server code continues to work unchanged
Default template parameter maintains HTTP behavior
No breaking changes to existing APIs

Example: Mixed HTTP/HTTPS Setup¶

#include "glaze/net/http_server.hpp"

int main() {
    // HTTP server for public content
    glz::http_server<> http_server;
    http_server.get("/", [](const glz::request& req, glz::response& res) {
        res.body("Public HTTP content");
    });

    // HTTPS server for secure content
    glz::https_server https_server;
    https_server.load_certificate("cert.pem", "key.pem")
                .get("/secure", [](const glz::request& req, glz::response& res) {
                    res.body("Secure HTTPS content");
                });

    // Start both servers
    std::thread http_thread([&]() { 
        http_server.bind(8080).start(); 
    });

    std::thread https_thread([&]() { 
        https_server.bind(8443).start(); 
    });

    http_thread.join();
    https_thread.join();

    return 0;
}

Troubleshooting¶

OpenSSL Not Found¶

If CMake cannot find OpenSSL:

# On Ubuntu/Debian
sudo apt-get install libssl-dev

# On macOS with Homebrew
brew install openssl
export PKG_CONFIG_PATH="/opt/homebrew/lib/pkgconfig"

# On Windows
vcpkg install openssl

Certificate Issues¶

Ensure certificate and key files are in PEM format
Check file permissions and paths
For production, use certificates from a trusted CA
For development, self-signed certificates are acceptable

Compilation Errors¶

Ensure GLZ_ENABLE_SSL is defined when using TLS features
Verify OpenSSL libraries are properly linked
Check that C++23 standard is enabled