Vix Core

Fast HTTP runtime • Router • Request/Response • JSON helpers • Production-ready primitives

core is the foundation of Vix.cpp. It provides the HTTP runtime primitives used across the ecosystem:

• vix::App — the main HTTP application
• routing (get/post/...) with path params
• Request / Response wrappers
• JSON helpers (vix::json) for fast structured responses
• query params, headers, body access
• predictable status codes + early return patterns

If Vix.cpp is a runtime, core is its execution engine for HTTP.

---

Quick start

Run the showcase example:

vix run examples/vix_routes_showcase.cpp

Then hit a few endpoints:

curl -i http://127.0.0.1:8080/
curl -i http://127.0.0.1:8080/health
curl -i http://127.0.0.1:8080/users/42
curl -i "http://127.0.0.1:8080/search?q=vix&page=2&limit=5"
curl -i http://127.0.0.1:8080/headers
curl -i http://127.0.0.1:8080/status/404

---

Minimal HTTP server

#include <vix.hpp>

using namespace vix;

int main()
{
  App app;

  app.get("/", [](Request&, Response& res) {
    res.json({"message", "Hello, Vix!"});
  });

  app.run(8080);
}

---

Routing model

Vix routes are designed to be:

• simple to read
• copy/paste friendly for real projects
• explicit about status codes and early returns

Basic routes

app.get("/hello", [](const Request&, Response&) {
  return vix::json::o("message", "Hello", "id", 20);
});

app.get("/txt", [](const Request&, Response&) {
  return "Hello world";
});

Status codes

app.get("/status/{code}", [](Request& req, Response& res) {
  const int code = /* parse */ 200;
  res.status(code).json({
    "status", code,
    "ok", (code >= 200 && code < 300)
  });
});

Path params

app.get("/users/{id}", [](Request& req, Response& res) {
  const std::string id = req.param("id", "0");

  if (id == "0") {
    res.status(404).json({"error", "User not found", "id", id});
    return;
  }

  res.json({"id", id, "vip", (id == "42")});
});

Query params

app.get("/search", [](Request& req, Response& res) {
  const std::string q = req.query_value("q", "");
  const std::string page = req.query_value("page", "1");
  const std::string limit = req.query_value("limit", "10");

  res.json({
    "q", q,
    "page", page,
    "limit", limit
  });
});

Headers

app.get("/headers", [](Request& req, Response& res) {
  res.json({
    "host", req.header("Host"),
    "user_agent", req.header("User-Agent"),
    "accept", req.header("Accept")
  });
});

---

Request body + JSON parsing

Core exposes the raw body and JSON parsing helpers.

app.get("/echo/body", [](Request& req, Response& res) {
  const std::string body = req.body();
  res.json({"bytes", (long long)body.size(), "body", body});
});

app.get("/echo/json", [](Request& req, Response& res) {
  const auto& j = req.json();
  res.json(j);
});

For defensive field access, the showcase demonstrates patterns like:

• check is_object()
• check contains() + type
• return defaults on missing fields

---

Mixed behaviors (send + return)

Vix supports both:

• explicit response (res.send, res.json)
• return-value auto-send (string or JSON object)

If you already sent a response explicitly, the returned value is ignored.

app.get("/mix", [](Request&, Response& res) {
  res.status(201).send("Created");
  return vix::json::o("ignored", true);
});

This makes it easy to write handlers in a style similar to Node/FastAPI:

• short happy path
• early return on errors

---

Showcase example

The recommended living reference for the public API style is:

• examples/vix_routes_showcase.cpp

It includes:

• simple routes
• JSON responses (flat + nested)
• status codes
• path params (/users/{id})
• query params (?page=1&limit=20)
• headers
• request body + JSON parsing
• mixed behaviors (send + return)
• many copy/paste route patterns

---

How core fits in the umbrella

• core powers the HTTP runtime (vix::App, routing, request/response)
• middleware attaches on top of core (security, parsers, auth, cache)
• websocket can run standalone or alongside HTTP
• p2p_http uses core to expose P2P control endpoints

---

Directory layout

Typical layout:

modules/core/
│
├─ include/vix/
│  ├─ http/...
│  ├─ router/...
│  ├─ server/...
│  ├─ session/...
│  ├─ config/...
│  ├─ utils/...
│  └─ vix.hpp            # umbrella include for HTTP runtime
│
└─ examples/
   └─ vix_routes_showcase.cpp

---

License

MIT — same as Vix.cpp

Repository: https://github.com/vixcpp/vix