Lab4: Sentiment Analysis only works randomly, and requests.get() does't work

[cheimu]

Two problems when doing lab4:

1. When I try lab4 function chaining, I firstly try echo -n "California is great, it's always sunny there." | faas-cli invoke sentimentanalysis, sometimes it works, but most of time it returns: Server returned unexpected status code: 502 -
2. When I try function chaining using exactly same code in lab4, but exceptions raised. Cannot recognize gateway in url.

Expected Behaviour

1. $ echo -n "California is great, it's always sunny there." | faas-cli invoke sentimentanalysis {"polarity": 0.8, "sentence_count": 1, "subjectivity": 0.75}
2. "That was probably positive"

Current Behaviour

1. Server returned unexpected status code: 502 -
2. Server returned unexpected status code: 500 - exit status 1
Traceback (most recent call last):
File "/home/app/python/urllib3/connection.py", line 169, in _new_conn
conn = connection.create_connection(
File "/home/app/python/urllib3/util/connection.py", line 73, in create_connection
for res in socket.getaddrinfo(host, port, family, socket.SOCK_STREAM):
File "/usr/local/lib/python3.9/socket.py", line 953, in getaddrinfo
for res in _socket.getaddrinfo(host, port, family, type, proto, flags):
socket.gaierror: [Errno -2] Name does not resolve

During handling of the above exception, another exception occurred: Traceback (most recent call last): File "/home/app/python/urllib3/connectionpool.py", line 699, in urlopen httplib_response = self._make_request( File "/home/app/python/urllib3/connectionpool.py", line 394, in _make_request conn.request(method, url, **httplib_request_kw) File "/home/app/python/urllib3/connection.py", line 234, in request super(HTTPConnection, self).request(method, url, body=body, headers=headers) File "/usr/local/lib/python3.9/http/client.py", line 1255, in request self._send_request(method, url, body, headers, encode_chunked) File "/usr/local/lib/python3.9/http/client.py", line 1301, in _send_request self.endheaders(body, encode_chunked=encode_chunked) File "/usr/local/lib/python3.9/http/client.py", line 1250, in endheaders self._send_output(message_body, encode_chunked=encode_chunked) File "/usr/local/lib/python3.9/http/client.py", line 1010, in _send_output self.send(msg) File "/usr/local/lib/python3.9/http/client.py", line 950, in send self.connect() File "/home/app/python/urllib3/connection.py", line 200, in connect conn = self._new_conn() File "/home/app/python/urllib3/connection.py", line 181, in _new_conn raise NewConnectionError( urllib3.exceptions.NewConnectionError: : Failed to establish a new connection: [Errno -2] Name does not resolve

Possible Solution

Steps to Reproduce (for bugs)

Context

Your Environment

• FaaS-CLI version ( Full output from: faas-cli version ): 0.13.6

• Docker version ( Full output from: docker version ): Client: Docker Engine - Community
  Cloud integration: 1.0.7
  Version: 20.10.2
  API version: 1.41
  Go version: go1.13.15
  Git commit: 2291f61
  Built: Mon Dec 28 16:12:42 2020
  OS/Arch: darwin/amd64
  Context: default
  Experimental: true
  Server: Docker Engine - Community
  Engine:
  Version: 20.10.2
  API version: 1.41 (minimum version 1.12)
  Go version: go1.13.15
  Git commit: 8891c58
  Built: Mon Dec 28 16:15:28 2020
  OS/Arch: linux/amd64
  Experimental: false
  containerd:
  Version: 1.4.3
  GitCommit: 269548fa27e0089a8b8278fc4fc781d7f65a939b
  runc:
  Version: 1.0.0-rc92
  GitCommit: ff819c7e9184c13b7c2607fe6c30ae19403a7aff
  docker-init:
  Version: 0.19.0
  GitCommit: de40ad0

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

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

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

[cheimu]

I guess I know where the problem is my first question and totally fix my second question where requests.get() does't work.

The solution to my second question: requests.get() does't work
the lab4's spec has one typo and one place a little bit confusing
1 typo. It says

Kubernetes

Suffix the gateway host with openfaas namespace:

    r = requests.get("http://gateway.openfaas:8080/function/sentimentanalysis", text= test_sentence)

But it should be r = requests.get("http://gateway.openfaas:8080/function/sentimentanalysis", data= test_sentence) instead. It's data not text !!!

2. Confusion. Spec says

Kubernetes

Suffix the gateway host with openfaas namespace:

    r = requests.get("http://gateway.openfaas:8080/function/sentimentanalysis", text= test_sentence)

Or via an environmental variable:

    gateway_hostname = os.getenv("gateway_hostname", "gateway") # uses a default of "gateway" for when "gateway_hostname" is not set
    test_sentence = "California is great, it's always sunny there."
    r = requests.get("http://" + gateway_hostname + ":8080/function/sentimentanalysis", data= test_sentence)

However, "Or via an environmental variable" part description is the syntax for swarm rather than for k8s. For k8s it should be
r = requests.get("http://" + gateway_hostname + ".openfaas:8080/function/sentimentanalysis", data= test_sentence) instead. K8s requires namespace openfaas.

As for my first question: Sentiment Analysis only works randomly
I can close the issue, since I think it is because sentimentanalysis takes a long time to deploy and my open-faas service is not stable, somethings kubectl port-forward svc/gateway -n openfaas 8080:8080 got broken. E0304 18:44:15.028897 9123 portforward.go:340] error creating error stream for port 8080 -> 8080: EOF Could I get confirmed? Thank you in advance!