use part body when writing to file

src/main.zig

@@ -58,6 +58,7 @@ const ContentDisposition = struct {
 const Part = struct {
     disposition: ContentDisposition,
     content_type: []const u8,
+    body: []const u8,
 };
 
 const Multipart = struct {
@@ -67,24 +68,31 @@ const Multipart = struct {
 
     const Self = @This();
 
-    pub fn init(body: []const u8, content_type: []const u8) !Multipart {
+    // TODO: move boundary_buffer to allocator
+    pub fn init(body: []const u8, content_type: []const u8, boundary_buffer: []u8) !Multipart {
         // parse content_type into what we want (the boundary)
         var it = std.mem.split(content_type, ";");
         const should_be_multipart = it.next() orelse return error.MissingContentType;
+        std.log.debug("should be multipart: {s}", .{should_be_multipart});
         if (!std.mem.eql(u8, should_be_multipart, "multipart/form-data"))
             return error.InvalidContentType;
 
         const should_be_boundary = it.next() orelse return error.MissingBoundary;
+        std.log.debug("should be boundary: {s} {d}", .{ should_be_boundary, should_be_boundary.len });
         if (!std.mem.startsWith(u8, should_be_boundary, " boundary="))
             return error.InvalidBoundary;
 
         var boundary_it = std.mem.split(should_be_boundary, "=");
         _ = boundary_it.next();
         const boundary_value = boundary_it.next() orelse return error.InvalidBoundary;
+        std.log.debug("boundary value: {s} {d}", .{ boundary_value, boundary_value.len });
+
+        const actual_boundary_value = try std.fmt.bufPrint(boundary_buffer, "--{s}", .{boundary_value});
+        std.log.debug("actual boundary value: {s} {d}", .{ actual_boundary_value, actual_boundary_value.len });
 
         return Self{
             .stream = StreamT{ .buffer = body, .pos = 0 },
-            .boundary = boundary_value,
+            .boundary = actual_boundary_value,
         };
     }
 
@@ -92,14 +100,15 @@ const Multipart = struct {
         var reader = self.stream.reader();
         // first self.boundary.len+2 bytes MUST be boundary + \r + \n
         var boundary_buffer: [512]u8 = undefined;
-        const maybe_boundary_raw = (try reader.readUntilDelimiterOrEof(&boundary_buffer, '\r')).?;
+        const maybe_boundary_raw = (try reader.readUntilDelimiterOrEof(&boundary_buffer, '\n')).?;
 
         const maybe_boundary_strip1 = std.mem.trimRight(u8, maybe_boundary_raw, "\n");
         const maybe_boundary_strip2 = std.mem.trimRight(u8, maybe_boundary_strip1, "\r");
         if (!std.mem.eql(u8, maybe_boundary_strip2, self.boundary)) {
-            std.log.err("expected '{s}', got '{s}'", .{ self.boundary, maybe_boundary_strip2 });
+            std.log.err("expected '{s}' {}, got '{s}' {}", .{ self.boundary, self.boundary.len, maybe_boundary_strip2, maybe_boundary_strip2.len });
             return error.InvalidBoundaryBody;
         }
+        std.log.debug("got successful boundary {s}", .{maybe_boundary_strip2});
 
         // from there ownwards, its just http!
         var parser = hzzp.parser.request.create(hzzp_buffer, reader);
@@ -110,9 +119,14 @@ const Multipart = struct {
         var content_disposition: ?ContentDisposition = null;
         var content_type: ?[]const u8 = null;
 
+        std.log.debug("next bytes: {any}", .{self.stream.buffer[self.stream.pos..(self.stream.pos + 50)]});
+
         while (try parser.next()) |event| {
+            std.log.debug("got event: {}", .{event});
             switch (event) {
                 .status => unreachable,
+                .end => break,
+                .head_done => {},
                 .header => |header| {
                     // TODO lowercase header name
                     if (std.mem.eql(u8, header.name, "Content-Disposition")) {
@@ -125,24 +139,57 @@ const Multipart = struct {
 
                         while (disposition_it.next()) |disposition_part_raw| {
                             const disposition_part = std.mem.trim(u8, disposition_part_raw, " ");
+
+                            if (std.mem.eql(u8, disposition_part, "form-data")) continue;
+
+                            // we have an A=B thing
+                            var single_part_it = std.mem.split(disposition_part, "=");
+
+                            const inner_part_name = single_part_it.next().?;
+                            const inner_part_value_quoted = single_part_it.next().?;
+
+                            const inner_part_value = std.mem.trim(u8, inner_part_value_quoted, "\"");
+
+                            if (std.mem.eql(u8, inner_part_name, "name")) dispo_name = inner_part_value;
+                            if (std.mem.eql(u8, inner_part_name, "filename")) dispo_filename = inner_part_value;
                         }
 
                         content_disposition = ContentDisposition{
                             .name = dispo_name,
                             .filename = dispo_filename,
                         };
+                        std.log.debug("got content disposition for part! {}", .{content_disposition});
                     } else if (std.mem.eql(u8, header.name, "Content-Type")) {
                         content_type = header.value;
+                        std.log.debug("got content type for part! {s}", .{content_type});
                     }
                 },
-                .end => break,
-                else => @panic("shit"),
+                else => {
+                    std.log.err("unexpected event: {}", .{event});
+                    @panic("shit");
+                },
             }
         }
 
+        // the rest of the reader until we find a matching boundary is the part body.
+        // hzzp does not do it for us because it cant find a body encoding
+        // (content-length, content-encoding)
+        //
+        // we can use the fact that we know the reader is FixedBufferStream
+        // to extract the remaining body, then trim the boundary!
+        //
+        // THIS ASSUMES ONLY ONE FILE IS IN THE WIRE.
+
+        const remaining_body = self.stream.buffer[self.stream.pos..self.stream.buffer.len];
+
+        var end_boundary_buf: [512]u8 = undefined;
+        const boundary_end_marker = try std.fmt.bufPrint(&end_boundary_buf, "{s}--\r\n", .{self.boundary});
+        const actual_body = std.mem.trim(u8, remaining_body, boundary_end_marker);
+
         return Part{
             .disposition = content_disposition.?,
             .content_type = content_type.?,
+            .body = actual_body,
         };
     }
 };
@@ -162,27 +209,32 @@ fn uploadFile(response: *http.Response, request: http.Request) !void {
     if (content_type == null) return error.InvalidContentType;
 
     // parse multipart data
-    var multipart = try Multipart.init(request.body, content_type.?);
+    var boundary_buffer: [512]u8 = undefined;
+    var multipart = try Multipart.init(request.body, content_type.?, &boundary_buffer);
     var hzzp_buffer: [1024]u8 = undefined;
 
     while (try multipart.next(&hzzp_buffer)) |part| {
-        std.log.info("part: {}", .{part});
+        std.log.info(
+            "got part from multipart request! name='{s}' filename='{s}' content_type='{s}' length={d}",
+            .{ part.disposition.name, part.disposition.filename, part.content_type, part.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(part.body);
+
+        try response.writer().writeAll(image_path);
+        return;
     }
-
-    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 {