Uncaught TypeError: undefined is not a function

[mpjura]

Looking through open and closed issues, it seems a lot of folks are having problems similar to this. Various methods fail inconsistently with Uncaught TypeError: undefined is not a function. Mostly PUT.

Code to reproduce is here. Failures are inconsistent. I can get it to fail roughly 20% of the time.

var expect = require( "chai" ).expect;

describe( "SuperAgent", function() {
    var url = "http://test/foo",

    request = require( "superagent" ),
    server = require( "superagent-mocker" )( request );

    before( function() {
        server.get( url, function() {
            return "get all";
        });

        server.post( url, function() {
            return "post";
        });

        server.get( url + "/:id", function( req ) {
            return "get " + req.params.id;
        });

        server.put( url + "/:id", function( req ) {
            return "put " + req.params.id;
        });

        server.del( url + "/:id", function( req ) {
            return "del " + req.params.id;
        });
    });

    it( "GET all fails inconsistently", function( done ) {
        request.get( url ).end( function( err, res ) {
            expect( res ).to.equal( "get all" );
            done();
        });
    });

    it( "POST fails inconsistently", function( done ) {
        request.post( url )
        .set( { "Content-Type": "application/json" } )
        .send( { foo: "bar" } )
        .end( function( err, res ) {
            expect( res ).to.equal( "post" );
            done();
        });
    });

    it( "GET fails inconsistently", function( done ) {
        request.get( url + "/1" ).end( function( err, res ) {
            expect( res ).to.equal( "get 1" );
            done();
        });
    });

    it( "PUT fails inconsistently", function( done ) {
        request.put( url + "/1" )
        .set( { "Content-Type": "application/json" } )
        .send( { foo: "bar" } )
        .end( function( err, res ) {
            expect( res ).to.equal( "put 1" );
            done();
        });
    });

    it( "DELETE fails inconsistently", function( done ){ 
        request.del( url + "/1" ).end( function( err, res ) {
            expect( res ).to.equal( "del 1" );
            done();
        });
    });
} );

Mocha reporter output after a failure:

SuperAgent
    ✓ GET all fails inconsistently
    ✓ POST fails inconsistently
    ✓ GET fails inconsistently
    1) PUT fails inconsistently
    ✓ DELETE fails inconsistently


  4 passing (25ms)
  1 failing

  1) SuperAgent PUT fails inconsistently:
     Uncaught TypeError: undefined is not a function
      at Socket.socketErrorListener (_http_client.js:271:9)
      at net.js:950:16

[mpjura]

Similar issue: #687

[dafortune]

Hey Guys, I am having a similar issue, not only with "PUT" request but also with "GET" requests, I traced it back up to https://github.com/visionmedia/superagent/blob/master/lib/node/index.js#L736. #set and other methods internally calls #request() to create a request to work on. _callback attribute is set on #end, so _callback is not defined at that point. It seems that sometimes node emits an error before #end gets called and so we get this exception.

request.put( url + "/1" )
        // request() is called by `set` which creates the http request object and 
        // attaches `error` event handler, `#_callback` is not defined at this point. 
        // Sometimes node seems to emit an error at this point, before "end", which 
        // seems to be causing the problem.
        .set( { "Content-Type": "application/json" } )
        .send( { foo: "bar" } )
        .end( function( err, res ) {
            expect( res ).to.equal( "put 1" );
            done();
        });

A workaround this issue that worked for me:

    var req = request.put( url );

    // WORKAROUND: https://github.com/visionmedia/superagent/issues/741
    req._callback = function() {};

    req.set(...)

I could create a PR to fix this if you want.