convert options to CLI args

[displague]

The README.md today reflects only four options that can be defined via CLI. The pattern of METAL_ env vars and JSON config files (cloud-sa.json) is consistent with how Metal CLI is managed today: https://github.com/equinix/metal-cli/blob/main/internal/cli/root.go#L116-L171. By making the options (defined in README.md) CLI args, users will have a full set of methods to define options: args, env, config. This will improve the user experience through better discoverability and documentation of options.

As in Metal CLI, Viper could be used to replace the environment fetching code in CPEM:

cloud-provider-equinix-metal/metal/config.go

Lines 96 to 199 in 45dde1a

	// getMetalConfig returns a Config struct from a cloud config JSON file or environment variables
	func getMetalConfig(providerConfig io.Reader) (Config, error) {
	// get our token and project
	var config, rawConfig Config
	// providerConfig may be nil if no --cloud-config is provided
	if providerConfig != nil {
	configBytes, err := io.ReadAll(providerConfig)
	if err != nil {
	return config, fmt.Errorf("failed to read configuration : %w", err)
	}
	err = json.Unmarshal(configBytes, &rawConfig)
	if err != nil {
	return config, fmt.Errorf("failed to process json of configuration file at path %s: %w", providerConfig, err)
	}
	}
	// read env vars; if not set, use rawConfig
	config.AuthToken = override(os.Getenv(apiKeyName), rawConfig.AuthToken)
	config.ProjectID = override(os.Getenv(projectIDName), rawConfig.ProjectID)
	config.LoadBalancerSetting = override(os.Getenv(loadBalancerSettingName), rawConfig.LoadBalancerSetting)
	config.Facility = override(os.Getenv(facilityName), rawConfig.Facility)
	config.Metro = override(os.Getenv(metroName), rawConfig.Metro)
	if config.AuthToken == "" {
	return config, fmt.Errorf("environment variable %q is required if not in config file", apiKeyName)
	}
	if config.ProjectID == "" {
	return config, fmt.Errorf("environment variable %q is required if not in config file", projectIDName)
	}
	// get the local ASN
	localASN := os.Getenv(envVarLocalASN)
	switch {
	case localASN != "":
	localASNNo, err := strconv.Atoi(localASN)
	if err != nil {
	return config, fmt.Errorf("env var %s must be a number, was %s: %w", envVarLocalASN, localASN, err)
	}
	config.LocalASN = localASNNo
	case rawConfig.LocalASN != 0:
	config.LocalASN = rawConfig.LocalASN
	default:
	config.LocalASN = DefaultLocalASN
	}
	config.BGPPass = override(os.Getenv(envVarBGPPass), rawConfig.BGPPass)
	// set the annotations
	config.AnnotationLocalASN = override(os.Getenv(envVarAnnotationLocalASN), rawConfig.AnnotationLocalASN, DefaultAnnotationNodeASN)
	config.AnnotationPeerASN = override(os.Getenv(envVarAnnotationPeerASN), rawConfig.AnnotationPeerASN, DefaultAnnotationPeerASN)
	config.AnnotationPeerIP = override(os.Getenv(envVarAnnotationPeerIP), rawConfig.AnnotationPeerIP, DefaultAnnotationPeerIP)
	config.AnnotationSrcIP = override(os.Getenv(envVarAnnotationSrcIP), rawConfig.AnnotationSrcIP, DefaultAnnotationSrcIP)
	config.AnnotationBGPPass = override(os.Getenv(envVarAnnotationBGPPass), rawConfig.AnnotationBGPPass, DefaultAnnotationBGPPass)
	config.AnnotationNetworkIPv4Private = override(os.Getenv(envVarAnnotationNetworkIPv4Private), rawConfig.AnnotationNetworkIPv4Private, DefaultAnnotationNetworkIPv4Private)
	config.AnnotationEIPMetro = override(os.Getenv(envVarAnnotationEIPMetro), rawConfig.AnnotationEIPMetro, DefaultAnnotationEIPMetro)
	config.AnnotationEIPFacility = override(os.Getenv(envVarAnnotationEIPFacility), rawConfig.AnnotationEIPFacility, DefaultAnnotationEIPFacility)
	config.EIPTag = override(os.Getenv(envVarEIPTag), rawConfig.EIPTag)
	apiServer := os.Getenv(envVarAPIServerPort)
	switch {
	case apiServer != "":
	apiServerNo, err := strconv.Atoi(apiServer)
	if err != nil {
	return config, fmt.Errorf("env var %s must be a number, was %s: %w", envVarAPIServerPort, apiServer, err)
	}
	config.APIServerPort = int32(apiServerNo)
	case rawConfig.APIServerPort != 0:
	config.APIServerPort = rawConfig.APIServerPort
	default:
	// if nothing else set it, we set it to 0, to indicate that it should use whatever the kube-apiserver port is
	config.APIServerPort = 0
	}
	config.BGPNodeSelector = override(os.Getenv(envVarBGPNodeSelector), rawConfig.BGPNodeSelector)
	if _, err := labels.Parse(config.BGPNodeSelector); err != nil {
	return config, fmt.Errorf("BGP Node Selector must be valid Kubernetes selector: %w", err)
	}
	config.EIPHealthCheckUseHostIP = rawConfig.EIPHealthCheckUseHostIP
	if v := os.Getenv(envVarEIPHealthCheckUseHostIP); v != "" {
	useHostIP, err := strconv.ParseBool(v)
	if err != nil {
	return config, fmt.Errorf("env var %s must be a boolean, was %s: %w", envVarEIPHealthCheckUseHostIP, v, err)
	}
	config.EIPHealthCheckUseHostIP = useHostIP
	}
	return config, nil
	}

Once these arguments are defined via the CLI, they can included in the --help output and included in generated markdown generation (replacing the hand-maintained README.md table):

diff --git a/main.go b/main.go
index bc35f40..dcc4908 100644
--- a/main.go
+++ b/main.go
@@ -9,6 +9,8 @@ import (
        cloudcontrollerconfig "k8s.io/cloud-provider/app/config"
        "k8s.io/cloud-provider/options"
        "k8s.io/component-base/cli"
+       "github.com/spf13/cobra/doc"
+       "github.com/spf13/cobra"
        cliflag "k8s.io/component-base/cli/flag"
        _ "k8s.io/component-base/logs/json/register"
        _ "k8s.io/component-base/metrics/prometheus/clientgo" // for client metric registration
@@ -34,6 +36,25 @@ func main() {
 
        fss := cliflag.NamedFlagSets{}
        command := app.NewCloudControllerManagerCommand(ccmOptions, cloudInitializer, controllerInitializers, fss, wait.NeverStop)
+       command.AddCommand(&cobra.Command{
+               Use:   `docs <destination>`,
+               Short: "Generate command markdown documentation.",
+               Long:  "Generates command markdown documentation in the specified directory. Each command gets a markdown file.",
+               Example: `  # Generate documentation in the ./docs directory:
+       metal docs ./docs`,
+
+               DisableFlagsInUseLine: true,
+               Args:                  cobra.MatchAll(cobra.ExactArgs(1), cobra.OnlyValidArgs),
+               PersistentPreRunE: func(cmd *cobra.Command, args []string) error {
+                       cmd.SilenceUsage = true
+                       return nil
+               },
+               RunE: func(cmd *cobra.Command, args []string) error {
+                       cmd.SilenceUsage = true
+                       dest := args[0]
+                       return doc.GenMarkdownTree(cmd.Parent(), dest)
+               },
+       })
        code := cli.Run(command)
        os.Exit(code)
 }

The generated documentation could then be included in the docs/ directory (docs/cmd/?).

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/lifecycle stale

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The Kubernetes project currently lacks enough active contributors to adequately respond to all issues.

This bot triages un-triaged issues according to the following rules:

• After 90d of inactivity, lifecycle/stale is applied
• After 30d of inactivity since lifecycle/stale was applied, lifecycle/rotten is applied
• After 30d of inactivity since lifecycle/rotten was applied, the issue is closed

You can:

• Mark this issue as fresh with /remove-lifecycle rotten
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• Offer to help out with Issue Triage

Please send feedback to sig-contributor-experience at kubernetes/community.

/lifecycle rotten

[k8s-triage-robot]

The Kubernetes project currently lacks enough active contributors to adequately respond to all issues and PRs.

This bot triages issues according to the following rules:

• After 90d of inactivity, lifecycle/stale is applied
• After 30d of inactivity since lifecycle/stale was applied, lifecycle/rotten is applied
• After 30d of inactivity since lifecycle/rotten was applied, the issue is closed

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/close not-planned

[k8s-ci-robot]

@k8s-triage-robot: Closing this issue, marking it as "Not Planned".

In response to this:

The Kubernetes project currently lacks enough active contributors to adequately respond to all issues and PRs.

This bot triages issues according to the following rules:

• After 90d of inactivity, lifecycle/stale is applied
• After 30d of inactivity since lifecycle/stale was applied, lifecycle/rotten is applied
• After 30d of inactivity since lifecycle/rotten was applied, the issue is closed

You can:

• Reopen this issue with /reopen
• Mark this issue as fresh with /remove-lifecycle rotten
• Offer to help out with Issue Triage

Please send feedback to sig-contributor-experience at kubernetes/community.

/close not-planned

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[cprivitere]

/reopen

[k8s-ci-robot]

@cprivitere: Reopened this issue.

In response to this:

/reopen

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[cprivitere]

/remove-lifecycle rotten

[cprivitere]

/triage accepted