Azure 上的 SQL Server 连接到 REST API Express.js/Node.js [TypeError: req.sql is not a function]

Question

您好，我在使用 express4 连接到 Azure SQL Server 时遇到问题，非常繁琐。我正在尝试使用 Node/Express 服务器（REST API）在 react-native 中制作一个应用程序，但是在 express 中设置 express4-tedios 之后，出现了这个错误： req.sql 不是函数

TypeError: req.sql 不是函数

这是我在服务器文件夹上的 app.js

var createError = require('http-errors');
var express = require('express');
var path = require('path');
var cookieParser = require('cookie-parser');
var logger = require('morgan');
var cors = require("cors");
var tediousExpress = require('express4-tedious');

var indexRouter = require('./routes/index');
var usersRouter = require('./routes/users');
var testAPIRouter = require("./routes/testAPI");

var app = express();

app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'jade');

app.use(cors());
app.use(logger('dev'));
app.use(express.json());
app.use(express.urlencoded({ extended: false }));
app.use(cookieParser());
app.use(express.static(path.join(__dirname, 'public')));

app.use('/', indexRouter);
app.use('/users', usersRouter);
app.use("/testAPI", testAPIRouter);

app.use(function (req, res, next) {
  req.sql = tediousExpress(req, 
    {
    "server"  : "something.database.windows.net",
    "userName": "something",
    "password": "something",
    "options": { "encrypt": true, "database": "something" }
    }
    );
  next();
});

// catch 404 and forward to error handler
app.use(function(req, res, next) {
  next(createError(404));
});

// error handler
app.use(function(err, req, res, next) {
  // set locals, only providing error in development
  res.locals.message = err.message;
  res.locals.error = req.app.get('env') === 'development' ? err : {};

  // render the error page
  res.status(err.status || 500);
  res.render('error');
});

module.exports = app;

这是我运行 req.sql() 函数的 testAPI.js

var express = require("express");
var router = express.Router();

router.get('/', function (req, res) {

  req.sql("select * from Persons for json path")
      .into(res);

});

module.exports = router;

我非常感谢任何人的帮助。 :)

Answer 1

那是因为您在路由之后定义了 中间件。您必须首先定义此中间件。并且，调用要定义的路由。

例如：

app.use(function (req, res, next) {
  req.sql = tediousExpress(req, 
    {
    "server"  : "something.database.windows.net",
    "userName": "something",
    "password": "something",
    "options": { "encrypt": true, "database": "something" }
    }
    );
  next();
});

app.use('/', indexRouter);
app.use('/users', usersRouter);
app.use("/testAPI", testAPIRouter);