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src/http/headers.zig

@@ -89,8 +89,8 @@ pub const Fields = struct {
         }
     };
 
-    pub fn getList(self: Fields, key: []const u8) ?ListIterator {
+    pub fn getList(self: Fields, key: []const u8) ListIterator {
-        return if (self.unmanaged.get(key)) |hdr| ListIterator{ .remaining = hdr } else null;
+        return if (self.unmanaged.get(key)) |hdr| ListIterator{ .remaining = hdr } else ListIterator{ .remaining = "" };
     }
 
     pub fn put(self: *Fields, key: []const u8, val: []const u8) !void {
@@ -121,4 +121,32 @@ pub const Fields = struct {
     pub fn count(self: Fields) usize {
         return self.unmanaged.count();
     }
+
+    pub const CookieOptions = struct {
+        Secure: bool = false,
+        HttpOnly: bool = false,
+        SameSite: ?enum {
+            Strict,
+            Lax,
+            None,
+        } = null,
+    };
+
+    pub fn setCookie(self: *Fields, name: []const u8, value: []const u8, opt: CookieOptions) !void {
+        const cookie = try std.fmt.printAlloc(
+            self.allocator,
+            "{s}={s}{s}{s}{s}",
+            .{
+                name,
+                value,
+                if (opt.Secure) "; Secure" else "",
+                if (opt.HttpOnly) "; HttpOnly" else "",
+                if (opt.SameSite) |same_site| "; SameSite=" ++ @tagName(same_site) else "",
+            },
+        );
+        defer self.allocator.free(cookie);
+
+        // TODO: reduce unnecessary allocations
+        self.append("Set-Cookie", cookie);
+    }
 };

src/http/server/response.zig

@@ -43,8 +43,15 @@ fn writeFields(writer: anytype, headers: *const Fields) !void {
             if (ch == '\r' or ch == '\n') @panic("newlines not yet supported in headers");
         }
 
+        if (std.ascii.eqlIgnoreCase("Set-Cookie", header.key_ptr.*)) continue;
+
         try writer.print("{s}: {s}\r\n", .{ header.key_ptr.*, header.value_ptr.* });
     }
+
+    var cookie_iter = headers.getList("Set-Cookie");
+    while (cookie_iter.next()) |cookie| {
+        try writer.print("Set-Cookie: {s}\r\n", .{cookie});
+    }
 }
 
 fn writeChunk(writer: anytype, contents: []const u8) @TypeOf(writer).Error!void {