Accept parameters and credentials via environment variables

[wally007]

As discussed in python version of the Veeam exporter...
"
The new configuration's model allows to defined authentication model (user/passwd/attrs) identified by name; this model maybe should use user/passwd values set by env.
"
... could you please enhance this GO version so that at least some parameters (such as username/password/target) can be supplied (and take precedence if they are set) via environment variables ?

[peekjef72]

Please check pre-relaese 0.3.7

Give some feedbacks so that if it is ok for you, I can merge this fix to master branch.

Doc: Extract from README

Authentication

Most of the time the access to a http api requires an authentication. It is the case for the 3 contribs (hp3par, veeam, netscaler).
The exporter allows you 2 modes:

• to define the authentication parameters statically for each target.
• to define a dictionnary (map) of authentications and then to use it a target definition, or even to set it in the prometheus query.

The auth parameters are :

• mode: should be
  • basic: use http basic authentication: the "user" and "password" values will be sent in the http header request
  • token: use bearer token to authenticate
  • script: user, password will be used in the login script to access the api.
• user
• password
• token

The user, password and token values can be raw strings or retrive the values from environment variables. To use env var the value must be prefixed by "$env:" followed by the name of the variable.

  # use this auth_config to authenticate via env vars
  default:
    mode: script
    user: $env:VEEAM_EXPORTER_USER
    password: $env:VEEAM_EXPORTER_PASSWD

[wally007]

thank you

i haven't tried this GO exporter yet.

I was able add environment variables to the python version and it works great. Im more comfortable with python.

Once I get my head wrapped around GO, this httpapi exporter and how it works, I'd like to try it to fetch HPe Oneview stats and see if it work with their API as well.

[RaphDuf]

Hello,
I use environment variables to define my auth (user et password) and it works great. But to adjust my personnal version of exporter base on your project on different infra, I would like to set my host also by an environment var.
I saw that for auth you define check_env_var function, but I'm not familiar with GO and I don't find how to call it to set host like this.

[peekjef72]

Hi,
I can't imagine one use case to force a target to a single host : the exporter acts like blackbox_exporter so it has a "target" parameter for the /metrics entry point. it means that by default the configuration contains always a template named "default" that would be address for the specified target.

so that:

http://[exporter_host]:[exporter_port]/metrics?target=[target_name]

• if target_name is found in the config targets list, it will be used as-it (with the parameters defined),
• else if not found, the parameters defined in default "target" will be use: auth (user, pass), scheme, port...
  • it means that you can set target_name :
    • as [target_name] = "my_fully_qualified_domain_name"
    • or [target_name] = https://my_fully_qualified_domain_name:port"
      there are others combinaisons of parameters you can use : see README.md

But if you really want to use a envvar I suggest to modify the code: I can't release a new version right now because of devs already in progress on v 0.4.1, but will include this in the next release.

from main branch in config.go:

		if strings.ToLower(t.Host) == "template" {
			t.targetType = TargetTypeModel
		} else {
			t.Host = check_env_var(t.Host)
		}

Hope it can help.

May I ask some questions ?

• which version to do use ?
• do you use a contribution (veeam, netscaler... ) or a custom "profile" ?

JFPIK-

[peekjef72]

release in 0.4.1

please give a feedback.

[RaphDuf]

Thank you, I haven't test the new release for the moment but your code work great for my usage.
For the moment I'm still using the version 0.3.7 and I use a custom profile.
The env var for host help me to deploy the same target configuration on different environments without having different target, like this it's lite and easy to have an automatic deploy.