From 745ab76dd3704a10031d1b0c10efc91d218c91f2 Mon Sep 17 00:00:00 2001
From: Bob Farrell <git@bob.frl>
Date: Wed, 29 Nov 2023 20:43:24 +0000
Subject: [PATCH] Initial commit

---
 .gitignore |   2 +
 get/foo    |   1 +
 main.zig   | 136 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 139 insertions(+)
 create mode 100644 .gitignore
 create mode 100644 get/foo
 create mode 100644 main.zig

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..75e0ab9
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,2 @@
+TODO.md
+main
diff --git a/get/foo b/get/foo
new file mode 100644
index 0000000..65ab103
--- /dev/null
+++ b/get/foo
@@ -0,0 +1 @@
+hellhelloo
diff --git a/main.zig b/main.zig
new file mode 100644
index 0000000..68ca81c
--- /dev/null
+++ b/main.zig
@@ -0,0 +1,136 @@
+const std = @import("std");
+
+const HttpServerOptions = struct {
+    use_cache: bool,
+};
+
+const HttpServer = struct {
+    server: std.http.Server,
+    allocator: std.mem.Allocator,
+    page_cache: std.StringHashMap([]const u8),
+    port: u16,
+    host: []const u8,
+    options: HttpServerOptions,
+
+    const Self = @This();
+
+    pub fn init(
+        allocator: std.mem.Allocator,
+        cache: std.StringHashMap([]const u8),
+        host: []const u8,
+        port: u16,
+        options: HttpServerOptions,
+    ) HttpServer {
+        const server = std.http.Server.init(allocator, .{ .reuse_address = true });
+
+        return .{
+            .server = server,
+            .allocator = allocator,
+            .page_cache = cache,
+            .host = host,
+            .port = port,
+            .options = options,
+        };
+    }
+
+    pub fn deinit(self: *Self) void {
+        self.server.deinit();
+    }
+
+    pub fn listen(self: *Self) !void {
+        const address = std.net.Address.parseIp(self.host, self.port) catch unreachable;
+
+        try self.server.listen(address);
+        std.debug.print(
+            "Listening on http://{s}:{} [cache:{s}]\n",
+            .{ self.host, self.port, if (self.options.use_cache) "enabled" else "disabled" }
+        );
+        try self.processRequests();
+    }
+
+    fn processRequests(self: *Self) !void {
+        while (true) {
+            self.processNextRequest() catch |err| {
+                switch(err) {
+                    error.EndOfStream => continue,
+                    error.ConnectionResetByPeer => continue,
+                    else => return err,
+                }
+            };
+        }
+    }
+
+    fn processNextRequest(self: *Self) !void {
+        var response = try self.server.accept(.{ .allocator = self.allocator });
+        defer response.deinit();
+
+        try response.wait();
+
+        const content = try self.pageContent(response.request.method, response.request.target);
+
+        response.transfer_encoding = .{ .content_length = content.len };
+        try response.send();
+        try response.writeAll(content);
+        try response.finish();
+    }
+
+    fn pageContent(self: *Self, method: std.http.Method, target: []const u8) ![]const u8 {
+      var buffer: [1<<16]u8 = undefined;
+      const method_str = switch(method) {
+          .POST => "post",
+          else => "get"
+      };
+      const path = try std.mem.concat(self.allocator, u8, &[_][]const u8{ method_str, target });
+
+      // std.debug.print("{s} {s}\n", .{ method_str, target });
+
+      if (self.options.use_cache and self.page_cache.contains(path)) {
+        defer self.allocator.free(path);
+
+        if (self.page_cache.get(path)) |cached_content| return cached_content;
+      }
+
+      const content = std.fs.cwd().readFile(path, &buffer) catch |err| {
+        return switch(err) {
+            error.FileNotFound => {
+                std.debug.print("File not found: {s}", .{path});
+                return "";
+            },
+            else => err
+        };
+      };
+
+      try self.page_cache.put(path, content);
+
+      return content;
+    }
+};
+
+pub fn main() !void {
+    var general_purpose_allocator = std.heap.GeneralPurposeAllocator(.{}){};
+    defer std.debug.assert(general_purpose_allocator.deinit() == .ok);
+    const allocator = general_purpose_allocator.allocator();
+    var page_cache = std.StringHashMap([]const u8).init(allocator);
+    defer page_cache.deinit();
+
+    const args = try std.process.argsAlloc(allocator);
+    defer std.process.argsFree(allocator, args);
+
+    const host: []const u8 = if (args.len > 1) args[1] else "127.0.0.1";
+    const port: u16 = if (args.len > 2) try std.fmt.parseInt(u16, args[2], 10) else 3040;
+
+    var server: HttpServer = HttpServer.init(
+        allocator,
+        page_cache,
+        host,
+        port,
+        HttpServerOptions{ .use_cache = false },
+    );
+
+    defer server.deinit();
+
+    server.listen() catch |err| {
+        std.debug.print("{}\nExiting.\n", .{err});
+        return err;
+    };
+}