I had tried set the header, but it does not work. I put return at the end of every lines already. Therefore it should not execute res.json(data) twice.
Please correct me if I am wrong.
app.js
var express = require('express');
var path = require('path');
var favicon = require('serve-favicon');
var logger = require('morgan');
var cookieParser = require('cookie-parser');
var bodyParser = require('body-parser');
var routes = require('./routes/index');
//var users = require('./routes/users');
var api = require('./routes/api');
var users_page = require('./routes/users_page');
var quizzes = require('./routes/quizzes');
var subjects = require('./routes/subjects');
var questions = require('./routes/questions');
var app = express();
// view engine setup
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'jade');
// uncomment after placing your favicon in /public
//app.use(favicon(__dirname + '/public/favicon.ico'));
app.use(logger('dev'));
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: false }));
app.use(cookieParser());
app.use(express.static(path.join(__dirname, 'public')));
app.use('/', routes);
//app.use('/users', users);
app.use('/api', api);
app.use('/users',users_page);
app.use('/quizzes', quizzes);
app.use('/subjects',subjects);
app.use('/questions',questions);
// catch 404 and forward to error handler
app.use(function(req, res, next) {
var err = new Error('Not Found');
err.status = 404;
next(err);
});
// error handlers
// development error handler
// will print stacktrace
if (app.get('env') === 'development') {
app.use(function(err, req, res, next) {
res.status(err.status || 500);
res.render('error', {
message: err.message,
error: err
});
});
}
// production error handler
// no stacktraces leaked to user
app.use(function(err, req, res, next) {
res.status(err.status || 500);
res.render('error', {
message: err.message,
error: {}
});
});
module.exports = app;
users_page.js
var express = require('express');
var router = express.Router();
var pg = require('pg');
var connectionString = process.env.DATABASE_URL || 'postgres://admin:admin@localhost:5432/mydb';
var userHandler = require('./userHandler_post.js');
router.post('/', userHandler.post);
var usr2 = require('./userHandler_getusrinfo.js');
router.get('/:username', usr2.getusrinfo);
var usr3 = require('./userHandler_upusr.js');
router.put('/:username', usr3.upusr);
var usr4 = require('./userHandler_del.js');
router.delete('/:username', usr4.del);
var usr5 = require('./userHandler_repasswd.js');
router.put('/reset_password/:username', usr5.repasswd);
var usr6 = require('./userHandler_getall.js');
router.get('/', usr6.get);
module.exports = router;
userHandler_getusrinfo.js :
var pg = require('pg');
var connectionString = process.env.DATABASE_URL || 'postgres://admin:admin@localhost:5432/mydb';
exports.getusrinfo = function(req, res, callback) {
var username = req.params.username;
pg.connect(connectionString, function(err, client, done) {
// Handle Errors
if(err) {
res.setHeader('Content-Type', 'application/json');
res.json(err);
return ;
}
var q2 = client.query("SELECT * FROM dugong.users WHERE UserName =$1 ;",[username]);
q2.on('error', function(error) {
var data = {success : false,
username : username,
reason : {errmsg : error.detail,
errid : error.code} };
res.setHeader('Content-Type', 'application/json');
res.json(data);
return callback();
});
q2.on('row', function(row, result) {
result.addRow(row);
return ;
});
q2.on('end', function(result) {
if (result.rowCount == 0) {
var data = {success : false,
username : username,
reason : {errmsg : "Username not found",
errid : 'q2'}};
res.setHeader('Content-Type', 'application/json');
res.json(data);
return callback();
}
var sumdata = {success: true,
username : result.rows[0].username,
... //omit to keep it short
FaxNumber : result.rows[0].faxnum
};
res.setHeader('Content-Type', 'application/json');
res.json(sumdata);
return callback();
});
done();
return ;
});
pg.end();
};
However, I got the annoying message like this. But program runs fine!
GET /users/Sari 500 45.026 ms - 89
Error: Can't set headers after they are sent.
at ServerResponse.OutgoingMessage.setHeader (_http_outgoing.js:335:11)
at ServerResponse.header (/home/sarit/4alls/mariner/node_modules/express/lib/response.js:700:10)
at ServerResponse.send (/home/sarit/4alls/mariner/node_modules/express/lib/response.js:154:12)
at fn (/home/sarit/4alls/mariner/node_modules/express/lib/response.js:934:10)
at View.exports.renderFile [as engine] (/home/sarit/4alls/mariner/node_modules/jade/lib/index.js:374:12)
at View.render (/home/sarit/4alls/mariner/node_modules/express/lib/view.js:93:8)
at EventEmitter.app.render (/home/sarit/4alls/mariner/node_modules/express/lib/application.js:566:10)
at ServerResponse.res.render (/home/sarit/4alls/mariner/node_modules/express/lib/response.js:938:7)
at /home/sarit/4alls/mariner/app.js:64:7
at Layer.handle_error (/home/sarit/4alls/mariner/node_modules/express/lib/router/layer.js:58:5)
Do I need to touch app.js:64:7 which is made by Express? If so, how can I do it in proper way?
