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POExpress 3 error middleware not being called
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copied!<p>I am trying to setup error handling for my express app and running into the following problem.</p> <p>I defined an error middleware and add it as the last middleware:</p> <pre><code>// error handler app.use(function(err, req, res, next) { console.log('JUST TESTING. ERROR HANLDER HAS BEEN CALLED...'); next(err); }); </code></pre> <p>Now I would expect this middleware to be called whenever an error occurs:</p> <pre><code>app.get('/datenschutz', function(req, res, next){ return next(new Error('Just testing')); // handle everything here }); </code></pre> <p>However my middleware is never called! The browser does display the stack trace however. This seems that there is another middleware that is catching this error and processing it before I can do anything about it.</p> <p>The problem is that I have no clue where this middleware could be defined, as I have a very simple setup:</p> <pre><code>// setup ssl for local testing var app = express(); app. use(express.static(__dirname + '/public')). use(express.bodyParser()). use(express.cookieParser()); </code></pre> <p>Why is my error handling middleware not being called? Where is this 'default' error handling taking place?</p> <p>Thanks!</p> <p><strong>* EDIT *</strong> I see that the middleware is indeed working. However this is the case if I call it from another middleware function. However it is not being invoked if the error occurs inside a function defined as an express route (GET, POST, etc..). This is very strange. If I add my error middleware to the route callbacks it then works:</p> <pre><code>app.get('/testError', function(req, res, next){ return next(new Error('Just testing')); // handle everything here }, function(err,req,res,next) { console.log('This error handler is called!!'); return next(); }); </code></pre> <p><strong>* EDIT 2 - FOUND ACCEPTABLE WORKAROUND **</strong> I am surprised it has to be done this way. As I had read many entries/questions about error handling in express and never found this possibility mentioned. However it seems that if an error ocurrs inside a route callback regular error middleware handlers will not pick it up. You will need to define an error handler at route level.</p> <pre><code>app.all('*', function(err,req,res,next) { console.log('This is a global error handler at route level....'); return next(err); }); </code></pre>

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