add image uploads

.gitignore

@@ -1,3 +1,4 @@
 zig-cache/
 deps.zig
+images/
 .zigmod/

src/main.zig

@@ -1,19 +1,72 @@
 const std = @import("std");
 const http = @import("apple_pie");
 
+const images_dir_path = "./images";
+
 pub fn main() anyerror!void {
     std.log.info("All your codebase are belong to us.", .{});
 
     var gpa = std.heap.GeneralPurposeAllocator(.{}){};
     defer _ = gpa.deinit();
 
+    const bind_addr = try std.net.Address.parseIp("0.0.0.0", 8080);
+    std.log.info("serving on {}", .{bind_addr});
+
+    // TODO: configurable path via env var
+    try std.fs.cwd().makePath(images_dir_path);
+
     try http.listenAndServe(
         &gpa.allocator,
-        try std.net.Address.parseIp("127.0.0.1", 8080),
+        bind_addr,
-        index,
+        comptime http.router.router(&[_]http.router.Route{
+            http.router.get("/", index),
+            http.router.post("/api/upload", uploadFile),
+            http.router.post("/:filename", fetchFile),
+        }),
     );
 }
 
 fn index(response: *http.Response, request: http.Request) !void {
     try response.writer().writeAll("Hello Zig!");
 }
+
+fn generateImageId(buffer: []u8) []const u8 {
+    var i: usize = 0;
+
+    const seed = @truncate(u64, @bitCast(u128, std.time.nanoTimestamp()));
+    var r = std.rand.DefaultPrng.init(seed);
+
+    while (i < 16) : (i += 1) {
+        // random ascii lowercase char
+        var idx = @intCast(u8, r.random.uintLessThan(u5, 24));
+        var letter = @as(u8, 97) + idx;
+        buffer[i] = letter;
+    }
+
+    return buffer[0..i];
+}
+
+fn uploadFile(response: *http.Response, request: http.Request) !void {
+    std.log.info("upload! got {d} bytes", .{request.body.len});
+
+    var image_id_buffer: [256]u8 = undefined;
+    const image_id = generateImageId(&image_id_buffer);
+
+    var image_path_buffer: [512]u8 = undefined;
+    const image_path = try std.fmt.bufPrint(
+        &image_path_buffer,
+        "{s}/{s}.jpg",
+        .{ images_dir_path, image_id },
+    );
+
+    const image_file = try std.fs.cwd().createFile(image_path, .{});
+    try image_file.writer().writeAll(request.body);
+
+    try response.writer().writeAll(image_path);
+}
+
+fn fetchFile(response: *http.Response, request: http.Request, filename: []const u8) !void {
+    std.log.info("got name: {s}", .{filename});
+    const images_dir = try std.fs.cwd().openDir(images_dir_path, .{});
+    try response.writer().writeAll("Hello Zig! fetch");
+}