Tools: express.use is not a function

[maxknee]

using version 4.3.3

00:03:11.325 [14:32:56] Starting 'wct:local'...
00:03:12.239 Received {"global":{"statements":100,"branches":100,"lines":100,"functions":100}}
00:03:13.468 Installing and starting Selenium server for local browsers
00:03:18.775 Selenium server running on port 44707
00:03:18.801 [14:33:04] 'wct:local' errored after 7.47 s
00:03:18.801 [14:33:04] Error: express.use is not a function

Polymer 1.6
wct 4.3.3

[rictic]

Hm, I'm having trouble reproducing. What project are you testing? Does that project have a local install of wct at ./node_modules/web-component-tester?

[rictic]

@justinfagnani I suspect this is another bug with resolving the library in the binary. I think we should probably just stop doing that. If people want that behavior they should use npm scripts or similar to deliberately run the local version. resolve is too magical.

[kienpham2000]

hey guys, we are having similar error failed on our Travis build 10 hours ago.

[19:59:24] 'wct:sauce' errored after 597 ms
[19:59:24] Error: express.use is not a function

[kienpham2000]

FYI when I lock down to this version, it works:
"web-component-tester": "4.0.3",

[web-padawan]

This was introduced in 4.3.3, works fine with 4.3.1.
Reproduced on Mac OS X, wct is installed locally and running through npm scripts.

[rictic]

Interesting. So it occurs with both local wct and wct-st. The integration tests are passing, and our travis build passes: https://travis-ci.org/PolymerElements/app-route/builds/154516607

@kienpham2000 can you link to your failing travis build? Does the associated project use express?

[kienpham2000]

@web-padawan you are right, we were locking our wct version at ^4.0.3 so it will be upgraded to latest 4.3.3. We removed the ^ and lock it at 4.0.3 and our Travis build is passing now

@rictic it's a Polymer repo, so no express at all.

Our .travis.yml config file:

env:
  global:
    - SAUCE_USERNAME=zzz
    - SAUCE_ACCESS_KEY=zzz

addons:
  sauce_connect: true

The Travis log:

Starting Sauce Connect
38.07s$ travis_start_sauce_connect
Using temp dir /tmp/sc.oU0z
/tmp/sc.oU0z ~/build/myapp
Downloading Sauce Connect
--2016-08-24 19:58:44--  http://saucelabs.com/downloads/sc-4.3.16-linux.tar.gz
Resolving saucelabs.com (saucelabs.com)... 162.222.75.243
Connecting to saucelabs.com (saucelabs.com)|162.222.75.243|:80... connected.
HTTP request sent, awaiting response... 200 OK
Length: 3624036 (3.5M) [binary/octet-stream]
Saving to: `sc-4.3.16-linux.tar.gz'
100%[======================================>] 3,624,036    295K/s   in 14s     
2016-08-24 19:58:58 (250 KB/s) - `sc-4.3.16-linux.tar.gz' saved [3624036/3624036]
Extracting Sauce Connect
Waiting for Sauce Connect readyfile
24 Aug 19:58:58 - Sauce Connect 4.3.16, build 2396 39e807b
24 Aug 19:58:58 - Using CA certificate bundle /etc/ssl/certs/ca-certificates.crt.
24 Aug 19:58:58 - Using CA certificate verify path /etc/ssl/certs.
24 Aug 19:58:58 - Starting up; pid 4184
24 Aug 19:58:58 - Command line arguments: sc-4.3.16-linux//bin/sc -i 103.1 -f sauce-connect-ready-16091 -l /home/travis/sauce-connect.log
24 Aug 19:58:58 - Log file: /home/travis/sauce-connect.log
24 Aug 19:58:58 - Pid file: /tmp/sc_client_103.1.pid
24 Aug 19:58:58 - Timezone: UTC GMT offset: 0h
24 Aug 19:58:58 - Using no proxy for connecting to Sauce Labs REST API.
24 Aug 19:58:58 - Resolving saucelabs.com to 162.222.75.243 took 14 ms.
24 Aug 19:58:58 - ***********************************************************
24 Aug 19:58:58 - A newer version of Sauce Connect (build 2818) is available!
24 Aug 19:58:58 - Download it here:
24 Aug 19:58:58 - https://saucelabs.com/downloads/sc-4.4.0-rc2-linux.tar.gz
24 Aug 19:58:58 - ***********************************************************
24 Aug 19:58:58 - Started scproxy on port 47363.
24 Aug 19:58:58 - Please wait for 'you may start your tests' to start your tests.
24 Aug 19:58:58 - Starting secure remote tunnel VM...
24 Aug 19:59:05 - Secure remote tunnel VM provisioned.
24 Aug 19:59:05 - Tunnel ID: xxx
24 Aug 19:59:05 - Secure remote tunnel VM is now: booting
24 Aug 19:59:20 - Secure remote tunnel VM is now: running
24 Aug 19:59:20 - Using no proxy for connecting to tunnel VM.
24 Aug 19:59:20 - Resolving tunnel hostname to 162.222.77.7 took 64ms.
24 Aug 19:59:20 - Starting Selenium listener...
24 Aug 19:59:20 - Establishing secure TLS connection to tunnel...
24 Aug 19:59:20 - Selenium listener started on port 4445.
24 Aug 19:59:21 - Sauce Connect is up, you may start your tests.
~/build/myapp
2.12s$ gulp wct:sauce
[19:59:23] Using gulpfile ~/build/myapp/gulpfile.js
[19:59:23] Starting 'wct:sauce'...
Received undefined
[19:59:24] 'wct:sauce' errored after 597 ms
[19:59:24] Error: express.use is not a function
The command "gulp wct:sauce" exited with 1.
sauce_connect.stop
Stopping Sauce Connect
6.02s$ travis_stop_sauce_connect
24 Aug 19:59:24 - Waiting for graceful Sauce Connect shutdown
Got signal 15
24 Aug 19:59:24 - Cleaning up.
24 Aug 19:59:24 - Removing tunnel ef0321e6bbde4906a0a4839e712512fc.
Waiting for graceful Sauce Connect shutdown
Waiting for graceful Sauce Connect shutdown
Waiting for graceful Sauce Connect shutdown
Waiting for graceful Sauce Connect shutdown
24 Aug 19:59:28 - All jobs using tunnel have finished.
24 Aug 19:59:28 - Waiting for the connection to terminate...
Waiting for graceful Sauce Connect shutdown
24 Aug 19:59:29 - Connection closed (8).
24 Aug 19:59:29 - Goodbye.
Sauce Connect shutdown complete
Done. Your build exited with 1.

[rictic]

@kienpham2000 does your app use express? What does npm ls | grep express show?

[kienpham2000]

@rictic it's a Polymer repo, all frontend stuff. But using your command, it does show express:

$ npm ls | grep express
│ │   ├─┬ [email protected]
npm│ │ │ │ │ │ │   │ │   └─┬ [email protected]
 ERR! peer dep missing: eslint-plugin-react@^4.0.0, required by [email protected]
│ ├─┬ [email protected]

[rictic]

Yeah, two very different versions of express. I suspect that our use of resolve in the wct binary is messing things up. Unsure why this would be new, but I don't see what else would do it.

Would you (or someone else who's hitting this issue) mind cloning wct, checking out the no-resolve branch, installing and testing to see if it resolves the issue?

[maxknee]

Pulled down no-resolve branch and still happening.

├── @types/[email protected] extraneous
│ │   ├─┬ [email protected]
│   │   │   └─┬ [email protected]
│ ├── [email protected] extraneous](url)

[10:58:36] 'wct:local' errored after 2.17 s
[10:58:36] Error: express.use is not a function
10:58:36.629 INFO - Shutting down...

[web-padawan]

@rictic any updates on this?
Reproduced with the following config:

Selenium server running on port 39362

TypeError: express.use is not a function

npm ERR! Linux 4.4.0-22-generic
npm ERR! argv "/usr/bin/nodejs" "/usr/bin/npm" "run" "testAllWithoutCoverage"
npm ERR! node v6.5.0
npm ERR! npm  v3.10.3

[AdamKorczynski]

The problem is Context.emitHook is designed to support hooks which are Promises and hooks which use callbacks.
Context.emitHook only binds arguments if arguments.length > 2. webserver.ts emits the prepare:webserver hook with only one argument, which is the Express middleware. Because in this case arguments.length > 2 resoves to false, the argment isn't bound.
M preference is to remove the callback hook option and enforce all hooks to use Promises, solution here: https://github.com/AdamKorczynski/web-component-tester/tree/bug/373/removeCallback
But that breaks the wct-sauce plugin which uses callbacks.
Instead, I've submitted a PR with an empty callback added to the prepare:webserver emitHook and incuded a unit test which makes the behavior explicit.
If neither solution is suitable, it will at least point you to the right place.
Submitted PR https://github.com/Polymer/web-component-tester/pull/399

[fincha]

have this problem with 5.0.0

sudo wct --skip-selenium-install

Received undefined
Starting Selenium server for local browsers
Selenium server running on port 61343

TypeError: express.use is not a function

npm ERR! Test failed. See above for more details.

[lukasoppermann]

How is the status on this? It is an important fix to get istanbul for code coverage running.

[justinfagnani]

I'm taking a look at @AdamKorczynski 's PR to fix this

[lukasoppermann]

Yeahhh.

[web-padawan]

I confirm this issue stil can be reproduced with istanbul plugin. Here is the row causing it.

Without using that plugin, all seems to work fine with wct-local 2.0.13 on my Mac and Win 7 as well.

[web-padawan]

Ping @justinfagnani
Should we open the issue for web-component-tester-istanbul?
Still have to use 4.3.1 to get coverage working.

[justinfagnani]

web-component-tester-istanbul could definitely work around the issue.

I looked at @AdamKorczynski's PR ( https://github.com/Polymer/web-component-tester/pull/399 ) and felt there was a more fundamental fix, I'll ping him there as well.

[justinfagnani]

Scratch that, I fixed this in https://github.com/Polymer/web-component-tester/pull/445