Info Metric Value Type Support #583
Description
For accomodating a collection of information as part of my requirement, I was initially under the impression that the Info metric will be able to support a key-value pair with the value field entered as a list of objects.
For Ex.
from prometheus_client import start_http_server, Info
start_http_server(8001)
inf = Info("name","desc")
inf.Info({"key":["val1","val2"]})
The above piece of code however throws the below Stack Trace:
Traceback (most recent call last):
File "/usr/lib/python3.6/wsgiref/handlers.py", line 137, in run
self.result = application(self.environ, self.start_response)
File "/path/to/prometheus_client_python/prometheus_client/exposition.py", line 52, in prometheus_app
status, header, output = _bake_output(registry, accept_header, params)
File "/path/to/prometheus_client_python/prometheus_client/exposition.py", line 40, in _bake_output
output = encoder(registry)
File "/path/to/prometheus_client_python/prometheus_client/exposition.py", line 137, in generate_latest
output.append(sample_line(s))
File "/path/to/prometheus_client_python/prometheus_client/exposition.py", line 95, in sample_line
for k, v in sorted(line.labels.items())]))
File "/path/to/prometheus_client_python/prometheus_client/exposition.py", line 95, in <listcomp>
for k, v in sorted(line.labels.items())]))
AttributeError: ("'list' object has no attribute 'replace'", Metric(ede, dfe, info, , [Sample(name='ede_info', labels={'key': ['str1', 'str2']}, value=1.0, timestamp=None, exemplar=None)]))
I'd want to know how this case must be handled:
- The
listtype as value should have been accepted, in which case the code must be modified - If
listtype isn't an acceptable value, then a readable error message must be thrown instead.
Activity
siddharths2710 commentedon Sep 28, 2020
In case of the latter, how will I be able to handle one-to-many associations ( Ex. The info of all clients to a given server in a distributed system? )
I can add a label for the server identifier, but my problem is that the client info is variable.
brian-brazil commentedon Sep 28, 2020
The docs show that it's a string value, and I don't think it makes sense to try and catch every way that a user tries to put in arbitrary invalid data types with a specific error. This is more a usage question, and it makes more sense to ask questions like this on the prometheus-users mailing list rather than in a GitHub issue. On the mailing list, more people are available to potentially respond to your question, and the whole community can benefit from the answers provided.