Make the remoteConfigFactory interface public

[idlebot]

While I understand that #1046 is the better solution, making the remoteConfigFactory interface public would allow getting configuration values from a different source.

In particular, I would like to implement a way to read values from Google Cloud Secret Manager.

By making this interface public it would be possible to simply do something like:

package vipergcpsecretmanager

import (
	"bytes"
	"context"
	"fmt"
	"io"

	secretmanager "cloud.google.com/go/secretmanager/apiv1"
	"github.com/spf13/viper"
	secretmanagerpb "google.golang.org/genproto/googleapis/cloud/secretmanager/v1"
)

type SecretManagerConfigProvider struct {
	projectID string
}

func (p SecretManagerConfigProvider) Get(rp viper.RemoteProvider) (io.Reader, error) {
	ctx := context.Background()
	client, err := secretmanager.NewClient(ctx)
	if err != nil {
		return nil, err
	}

	// Build the request.
	req := &secretmanagerpb.AccessSecretVersionRequest{
		Name: fmt.Sprintf("projects/%s/secrets/%s/versions/latest", p.projectID, rp.Path()),
	}

	// Call the API.
	result, err := client.AccessSecretVersion(ctx, req)
	if err != nil {
		return nil, err
	}

	return bytes.NewReader(result.Payload.Data), nil
}

func (p SecretManagerConfigProvider) Watch(rp viper.RemoteProvider) (io.Reader, error) {
	return bytes.NewReader([]byte{}), nil
}

func (p SecretManagerConfigProvider) WatchChannel(rp viper.RemoteProvider) (<-chan *viper.RemoteResponse, chan bool) {
	quitwc := make(chan bool)
	viperResponsCh := make(chan *viper.RemoteResponse)

	return viperResponsCh, quitwc
}

And set the factory from user code:

viper.RemoteConfig = &SecretManagerConfigProvider{
	projectID: "my-project-id-123"
}

[github-actions]

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[sagikazarmark]

You don't need the remoteConfigFactory interface to be public, in order to implement it. Your code should work as it is.

Here is an example using hashicorp vault as a remote backend: https://github.com/sagikazarmark/viperx

[idlebot]

Thanks!