我正在编写 API,想了解添加多个路由共享的中间件的好方法是什么。中间件在每个路由中执行相同的操作,例如验证主机/IP、验证用户等。 req 对象与每个中间件中的其他对象一起加载,例如 req.host、req.ip、req.username 等。
app.post("/route1", middleware1, middleware2, middleware3, middleware4);
app.post("/route2", middleware1, middleware2, middleware3, middleware4);
const middleware1 = (req, res, next) => {
// does something to validate user
req.username = "username"
next();
}
const middleware2 = (req, res, next) => {
// host validation
req.host = "something modified in validation"
next();
}
const middleware3 = (req, res, next) => {
// checks for mac and ip
req.mac = "mac addr"
next();
}
const middleware4 = (req, res, next) => {
res.send();
}
或者类似这样的东西:
app.post("/route1", middleware1);
app.post("/route2", middleware1);
const middleware1 = (req, res) => {
// does something to validate user
req.username = "username"
middleware2(req, res);
}
const middleware2 = (req, res) => {
// host validation
req.host = "something modified in validation"
middleware3(req, res);
}
const middleware3 = (req, res) => {
// checks for mac and ip
req.mac = "mac addr"
middleware4(req, res);
}
const middleware1 = (req, res) => {
res.send();
}
谢谢。
最佳答案
通常我不会直接从另一个中间件调用中间件。它混合了中间件逻辑的职责和中间件的使用位置。
Express 的可配置性比您想象的要高得多。您还可以在公共(public)路径中安装公共(public)中间件:
如果所有路由都使用中间件:
// How common middlewares are normally installed: app.post(middleware1); app.post(middleware2); app.post(middleware3); app.post(middleware4); // Alternative, less common way to do it: app.post(middleware1,middleware2,middleware3,middleware4);
如果只有特定模式网址使用中间件:
// Use a regexp: app.post(/route(1|2)/, middleware1, middleware2, middleware3, middleware4); // Or if you don't like regexp, use globs: app.post('route*', middleware1, middleware2, middleware3, middleware4); // Or a more specific glob pattern: app.post('route1?2?', middleware1, middleware2, middleware3, middleware4);
如果子路径中的所有 url 都使用中间件。例如,假设
/route/...
中的所有 url 都使用中间件:const route = express.Router(); app.use('/route',route); route.post(middleware1); route.post(middleware2); route.post(middleware3); route.post(middleware4);
如果上述任何一个都不吸引您,您仍然可以使用第二个选项,但不是在彼此内部调用中间件,而是编写一个中间件来初始化中间件:
function commonMiddlewares (req, res, next) {
middleware1(req,res,function() {
middleware2(req,res,function() {
middleware3(req,res,function() {
middleware4(req,res,next);
});
});
});
}
可以用更少嵌套的方式编写:
function commonMiddlewares (req, res, next) {
function runMiddleware4 () {
middleware4(req,res,next);
}
function runMiddleware3 () {
middleware3(req,res,runMiddleware4);
}
function runMiddleware2 () {
middleware2(req,res,runMiddleware3);
}
middleware1(req,res,runMiddleware2);
}
关于javascript - Express 中的中间件链接,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/58279138/