Question about using AlpineFunction sample function

[udondan]

I am trying to convert a present Dockerfile into a FaaS function. I'm feeling like an idiot but I am not getting this to work. Failing with the simplest examples.

I tried this on CentOS and MacOS with the same results.

~/faas/sample-functions/AlpineFunction(master)$ ./build.sh
Sending build context to Docker daemon  6.144kB
Step 1/5 : FROM alpine:latest
latest: Pulling from library/alpine
Digest: sha256:f006ecbb824d87947d0b51ab8488634bf69fe4094959d935c0c103f4820a417d
Status: Downloaded newer image for alpine:latest
 ---> 76da55c8019d
Step 2/5 : ADD https://github.com/openfaas/faas/releases/download/0.6.5/fwatchdog /usr/bin
Downloading [==================================================>]  3.779MB/3.779MB
 ---> ece807143b7a
Step 3/5 : RUN chmod +x /usr/bin/fwatchdog
 ---> Running in dd57cc6b9e8d
 ---> c1e19230ec65
Removing intermediate container dd57cc6b9e8d
Step 4/5 : HEALTHCHECK --interval=5s CMD [ -e /tmp/.lock ] || exit 1
 ---> Running in a0cd65be6e00
 ---> 63a0e7acb5bb
Removing intermediate container a0cd65be6e00
Step 5/5 : CMD fwatchdog
 ---> Running in 34bd0c8a679d
 ---> c46cb76483bc
Removing intermediate container 34bd0c8a679d
Successfully built c46cb76483bc
Successfully tagged functions/alpine:latest

~/faas/sample-functions/AlpineFunction(master) $ faas-cli deploy --image=functions/alpine:latest --name=func_alpine_test
No existing service to remove
Deployed.
URL: http://localhost:8080/function/func_alpine_test

200 OK

$ faas-cli invoke func_alpine_test
Reading from STDIN - hit (Control + D) to stop.
Server returned unexpected status code: 500 - Can't reach service: func_alpine_test

$ docker service logs --no-trunc=true func_alpine_test
func_alpine_test.1.tagfq6tcxmbaw958szm2ecnhn@moby    | 2017/10/15 14:16:21 Writing lock-file to: /tmp/.lock
func_alpine_test.1.tagfq6tcxmbaw958szm2ecnhn@moby    | 2017/10/15 14:16:41 http: panic serving 10.0.0.5:38048: runtime error: invalid memory address or nil pointer dereference
func_alpine_test.1.tagfq6tcxmbaw958szm2ecnhn@moby    | goroutine 18 [running]:
func_alpine_test.1.tagfq6tcxmbaw958szm2ecnhn@moby    | net/http.(*conn).serve.func1(0xc420074300)
func_alpine_test.1.tagfq6tcxmbaw958szm2ecnhn@moby    | 	/usr/local/go/src/net/http/server.go:1491 +0x12a
func_alpine_test.1.tagfq6tcxmbaw958szm2ecnhn@moby    | panic(0x634ba0, 0xc42000a030)
func_alpine_test.1.tagfq6tcxmbaw958szm2ecnhn@moby    | 	/usr/local/go/src/runtime/panic.go:458 +0x243
func_alpine_test.1.tagfq6tcxmbaw958szm2ecnhn@moby    | main.pipeRequest(0xc42006c200, 0x7817c0, 0xc4200d8000, 0xc4200c40f0, 0xc42000a0b0, 0x4, 0x67b701)
func_alpine_test.1.tagfq6tcxmbaw958szm2ecnhn@moby    | 	/go/src/github.com/alexellis/faas/watchdog/main.go:145 +0x3db
func_alpine_test.1.tagfq6tcxmbaw958szm2ecnhn@moby    | main.makeRequestHandler.func1(0x7817c0, 0xc4200d8000, 0xc4200c40f0)
func_alpine_test.1.tagfq6tcxmbaw958szm2ecnhn@moby    | 	/go/src/github.com/alexellis/faas/watchdog/main.go:219 +0xe7
func_alpine_test.1.tagfq6tcxmbaw958szm2ecnhn@moby    | net/http.HandlerFunc.ServeHTTP(0xc42004ef60, 0x7817c0, 0xc4200d8000, 0xc4200c40f0)
func_alpine_test.1.tagfq6tcxmbaw958szm2ecnhn@moby    | 	/usr/local/go/src/net/http/server.go:1726 +0x44
func_alpine_test.1.tagfq6tcxmbaw958szm2ecnhn@moby    | net/http.(*ServeMux).ServeHTTP(0x79bd40, 0x7817c0, 0xc4200d8000, 0xc4200c40f0)
func_alpine_test.1.tagfq6tcxmbaw958szm2ecnhn@moby    | 	/usr/local/go/src/net/http/server.go:2022 +0x7f
func_alpine_test.1.tagfq6tcxmbaw958szm2ecnhn@moby    | net/http.serverHandler.ServeHTTP(0xc420074200, 0x7817c0, 0xc4200d8000, 0xc4200c40f0)
func_alpine_test.1.tagfq6tcxmbaw958szm2ecnhn@moby    | 	/usr/local/go/src/net/http/server.go:2202 +0x7d
func_alpine_test.1.tagfq6tcxmbaw958szm2ecnhn@moby    | net/http.(*conn).serve(0xc420074300, 0x781d00, 0xc42006c500)
func_alpine_test.1.tagfq6tcxmbaw958szm2ecnhn@moby    | 	/usr/local/go/src/net/http/server.go:1579 +0x4b7
func_alpine_test.1.tagfq6tcxmbaw958szm2ecnhn@moby    | created by net/http.(*Server).Serve
func_alpine_test.1.tagfq6tcxmbaw958szm2ecnhn@moby    | 	/usr/local/go/src/net/http/server.go:2293 +0x44d

The same happens with other examples.

Expected Behaviour

Not failing

Current Behaviour

Failing, invoking a function shows:

Server returned unexpected status code: 500 - Can't reach service: func_alpine_test

Service log shows:

2017/10/15 14:16:41 http: panic serving 10.0.0.5:38048: runtime error: invalid memory address or nil pointer dereference

Possible Solution

Steps to Reproduce (for bugs)

1. Clone openfaas/faas
2. cd into sample-functions/AlpineFunction
3. build
4. deploy
5. invoke
6. Check service logs

Context

Your Environment

• Docker version docker version (e.g. Docker 17.0.05 ):

$ docker version
Client:
 Version:      17.09.0-ce
 API version:  1.32
 Go version:   go1.8.3
 Git commit:   afdb6d4
 Built:        Tue Sep 26 22:40:09 2017
 OS/Arch:      darwin/amd64

Server:
 Version:      17.09.0-ce
 API version:  1.32 (minimum version 1.12)
 Go version:   go1.8.3
 Git commit:   afdb6d4
 Built:        Tue Sep 26 22:45:38 2017
 OS/Arch:      linux/amd64
 Experimental: false

• faas-cli

  On CentOS:

$ faas-cli version
  ___                   _____           ____
 / _ \ _ __   ___ _ __ |  ___|_ _  __ _/ ___|
| | | | '_ \ / _ \ '_ \| |_ / _` |/ _` \___ \
| |_| | |_) |  __/ | | |  _| (_| | (_| |___) |
 \___/| .__/ \___|_| |_|_|  \__,_|\__,_|____/
      |_|

Commit: e804a60889e4d339762fb3643a315a173a963f26
Version: 0.4.18b

On MacOS:

$ faas-cli version
  ___                   _____           ____
 / _ \ _ __   ___ _ __ |  ___|_ _  __ _/ ___|
| | | | '_ \ / _ \ '_ \| |_ / _` |/ _` \___ \
| |_| | |_) |  __/ | | |  _| (_| | (_| |___) |
 \___/| .__/ \___|_| |_|_|  \__,_|\__,_|____/
      |_|

Commit: e804a60889e4d339762fb3643a315a173a963f26
Version: dev

• Are you using Docker Swarm or Kubernetes (FaaS-netes)?

  Swarm, single node

• Operating System and version (e.g. Linux, Windows, MacOS):

  MacOS 10.3 & CentOS 7.3.1611, same result

• Link to your project or a code example to reproduce issue:

  No project, failing with included example functions.

[alexellis]

Send your email to [email protected] and I'll invite you to slack. Someone should be able to help you there

[johnmccabe]

@udondan I'm able to reproduce this locally, having a look into it now

[johnmccabe]

Derek add label: question

[alexellis]

Please try the tutorials or samples. Tutorials are in faas repo under the guide folder.

[johnmccabe]

@udondan for your particular case I assume you're just attempting to run the basic provided function, in which case can you deploy with the following:

faas-cli deploy --image=functions/alpine:latest --name=func_alpine_test --fprocess="wc -l"

This will explicitly set the process to invoke in the function - have a look at the Dockerfile you can also see it there in a comment.

You should normally be able to just use the fprocess envvar in the image itself, but we currently have a bug (also spotted by @rgee0) in the CLI on deploy where it will set a default value thereby overriding the value set in the image - so for the moment deploying by explicitly setting it above should get you up and going. We'll raise a separate issue to track the CLI issue over in that repo.

[johnmccabe]

@udondan there's a fix in the pipeline for the CLI issue, can you let us know if the suggestion above gets you moving in the meantime.

[alexellis]

@udondan - just had a chance to look at this. AlpineFunction is a base image that will allow you to run built-in busybox commands as serverless functions - or to which you can add your own code.

So this would not work:

faas-cli deploy --image=functions/alpine:latest --name=func_alpine_test

You'd need to derive a container, add your code or packages and set the fprocess (see Dockerfile for comments) or set the fprocess at deploy time through a CLI flag as explained by John

faas-cli deploy --image=functions/alpine:latest --name=func_alpine_test --fprocess="sha512sum"

fprocess is documented on the TestDrive.md file and also over on the watchdog README.md file in the watchdog folder.

https://github.com/openfaas/faas/blob/master/TestDrive.md

https://github.com/openfaas/faas/tree/master/watchdog

I'd suggest you follow one of the CLI tutorials first - https://github.com/openfaas/faas/tree/master/guide

I.e. first Go/Python function.

[udondan]

AlpineFunction is a base image that will allow you to run built-in busybox commands as serverless functions

Yes, that's what I was aiming for. :)

You should normally be able to just use the fprocess envvar in the image itself, but we currently have a bug (also spotted by @rgee0) in the CLI on deploy where it will set a default value thereby overriding the value set in the image - so for the moment deploying by explicitly setting it above should get you up and going. We'll raise a separate issue to track the CLI issue over in that repo.

This explain it. I started with my own Dockerfile and then reduced it step by step until I ended up with an empty Alpine image calling a system function. I then used the AlpineFunction Dockerfile in the sample folder and of course also tried with the fprocess uncommented.

So yes, passing the --fprocess along with the deploy succeeds.

Also tested openfaas/faas-cli#170 and that also works.

Thanks folks.