快速处理多部分/表单数据错误："body must be object"

Question

我使用fastify-multer和JSON模式来提交可能包含文件的多部分表单数据。无论我做什么，tify总是给我一个糟糕的响应错误:

{
"statusCode": 400,
"error": "Bad Request",
"message": "body must be object"
}

这是我的index.ts:

const server = fastify();
server.register(require("@fastify/cors"));
server.register(multer.contentParser).after(() => {
if (!isProdEnv) {
server.register(require("@fastify/swagger"), {
/* ... */
});
}
server.register(require("@fastify/auth")).after(() => {
server.decorate("authenticateRequest", authenticateRequest);
server.decorate("requireAuthentication", requireAuthentication);
server.addHook("preHandler", server.auth([server.authenticateRequest]));
server.register(indexRouter);
server.register(authRouter, { prefix: "/auth" });
server.register(usersRouter, { prefix: "/users" });
server.register(listsRouter, { prefix: "/lists" });
server.register(postsRouter, { prefix: "/posts" });
server.register(searchRouter, { prefix: "/search" });
server.register(settingsRouter, { prefix: "/settings" });
});
});
server.setErrorHandler((err, req, res) => {
req.log.error(err.toString());
res.status(500).send(err);
});

和/posts/create端点:

const postsRouter = (server: FastifyInstance, options: FastifyPluginOptions, next: HookHandlerDoneFunction) => {
server.post(
"/create",
{
schema: {
consumes: ["multipart/form-data"],
body: {
content: {
type: "string"
},
media: {
type: "string",
format: "binary"
},
"media-description": {
type: "string"
}
}
},
preHandler: [server.auth([server.requireAuthentication]), uploadMediaFileToCloud]
},
postsController.createPost
);
next();
};
export default postsRouter;

请求旋度:

curl -X 'POST' 
'http://localhost:3072/posts/create' 
-H 'accept: */*' 
-H 'Authorization: Bearer eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJoYW5kbGUiOiJ1bGtrYSIsInVzZXJJZCI6IjYyNGQ5NmY4NzFhOTI2OGY2YzNjZWExZCIsImlhdCI6MTY1NzEwNTg5NCwiZXhwIjoxNjU3NDA1ODk0fQ.A5WO3M-NhDYGWkILQLVCPfv-Ve-e_Dlm1UYD2vj5UrQ' 
-H 'Content-Type: multipart/form-data' 
-F 'content=Test.' 
-F 'media=@flame-wolf.png;type=image/png' 
-F 'media-description=' 

为什么不工作?

Answer 1

编辑2:显然，对此有一个非常简单的解决方案:在preValidation钩子中使用multer而不是preHandler。因此，一段工作代码看起来像这样:

server.register(multer.contentParser).after(() => {
server.register(
(instance: FastifyInstance, options: FastifyPluginOptions, next: HookHandlerDoneFunction) => {
instance.post(
"/create",
{
schema: {
consumes: ["multipart/form-data"],
body: {
type: "object",
properties: {
content: {
type: "string"
},
media: {
type: "string",
format: "binary"
}
}
}
},
preValidation: multer({
limits: {
fileSize: 1024 * 1024 * 5
},
storage: multer.memoryStorage()
}).single("media")
},
(request: FastifyRequest, reply: FastifyReply) => {
const content = (request.body as any).content as string;
const file = (request as any).file as File;
if (file) {
delete file.buffer;
}
reply.send({
content,
file: JSON.stringify(file) || "No file selected"
});
}
);
next();
},
{ prefix: "/posts" }
);
});

---

编辑:在我把答案贴在下面之后，我找到了一个解决方案。为其他可能遇到同样问题的人更新我的答案。

首先,我从fastify-multer转向@fastify/multipart。然后我从media字段中删除了type属性。

media: {
format: "binary"
}

之后，我在注册@fastify/multipart时添加了{ addToBody: true }选项。

import fastifyMultipart from "@fastify/multipart";
server.register(fastifyMultipart, { addToBody: true }).after(() => { ... });

经过这些修改，media字段在request.body中可用。

---

老答:

似乎这些天我必须在这里回答我自己的问题。不管怎样，我知道怎么回事了。fasttify的内置模式验证不适合multipart/form-data。我玩的模式规范,以确保这是如此。因此，我从所有路由中删除了模式验证。我在这里的用例是将一个API从ExpressJS移植到fasttify，所以我使用express- oasis -generator生成了一个很好的Swagger JSON规范。我用它来生成Swagger UI，一切都很好。我希望spotify能齐心协力解决这个问题。