configmanager

Config Manager

Package used for retrieving application settings from various sources.

Currently supported variable and secrets implementations - AWS SecretsManager and AWS ParameterStore.

The Intended use is within containers to generate required application config that can later be sourced and then read by application at start up time so that e.g. K8s secrets don't need to be used for true "secrets" or jsut to avoid overly large configmaps

Must reference an existing token in a path like format.

GenVars will then write them to a file in this format:

export VAR=VALUE
export VAR2=VALUE2
...

Installation

Major platform binaries here

*nix binary

curl -L https://github.com/dnitsch/configmanager/releases/latest/download/configmanager-linux -o configmanager

MacOS binary

curl -L https://github.com/dnitsch/configmanager/releases/latest/download/configmanager-darwin -o configmanager

chmod +x configmanager
sudo mv configmanager /usr/local/bin

Download specific version:

curl -L https://github.com/dnitsch/configmanager/releases/download/v0.5.0/configmanager-`uname -s` -o configmanager

Usage

configmanager CLI for retrieving config or secret variables.
                Using a specific tokens as an array item

Usage:
  configmanager [command]

Available Commands:
  completion   Generate the autocompletion script for the specified shell
  help         Help about any command
  insert       Retrieves a value for token(s) specified and optionally writes to a file
  retrieve     Retrieves a value for token(s) specified
  string-input Retrieves all found token values in a specified string input
  version      Get version number configmanager

Flags:
  -h, --help                     help for configmanager
  -k, --key-separator string     Separator to use to mark a key look up in a map. e.g. AWSSECRETS#/token/map|key1 (default "|")
  -s, --token-separator string   Separator to use to mark concrete store and the key within it (default "#")
  -v, --verbose                  Verbosity level

Commands

retrieve

Useful for retrieving a series of tokens in CI or before app start

configmanager retrieve --token AWSSECRETS#/appxyz/service1-password --token AWSPARAMSTR#/appxyz/service2-password
source app.env

This will have written to a defaul out path app.env in current directory the below contents

export SERVICE1_PASSWORD='somepass!$@sdhf'
export SERVICE2_PASSWORD='somepa22$!$'

Once sourced you could delete the file, however the environment variables will persist in the process info /proc/someprocess

rm -f app.env
./startapp

By default the output path is app.env relative to the exec binary.

This can be overridden by passing in the --path param.

configmanager retrieve --token AWSSECRETS#/appxyz/service1-password --token AWSPARAMSTR#/appxyz/service12-settings --path /some/path/app.env
source /some/path/app.env
./startapp # psuedo script to start an application

Alternatively you can set the path as stdout which will reduce the need to save and source the env from file.

!Warning! about eval - if you are retrieving secrets from sources you don't control the input of - best to stick wtih the file approach and then delete the file.

eval "$(configmanager r -t AWSSECRETS#/appxyz/service1-password -t AWSPARAMSTR#/appxyz/service12-settings -p stdout)" && ./.ignore-out.sh

string-input

Replaces all the occurences of tokens inside strings and writes them back out to files.

Config Tokens

The token is made up of 3 parts:

• AWSSECRETS the strategy identifier to choose at runtime

• # separator - used for

• /path/to/parameter the actual path to the secret or parameter in the target system e.g. AWS SecretsManager or ParameterStore (it does assume a path like pattern might throw a runtime error if not found)

If contents of the AWSSECRETS#/appxyz/service1-password are a string then service1-password will be the key and converted to UPPERCASE e.g. SERVICE1_PASSWORD=som3V4lue

KeySeparator

Specifying a key seperator on token items that can be parsed as a K/V map will result in only retrieving the specific key from the map.

e.g. if contents of the AWSSECRETS#/appxyz/service1-db-config are parseable into the below object

{
	"host": "db.internal",
	"port": 3306,
	"pass": "sUp3$ecr3T!",
}

Then you can access the single values like this AWSSECRETS#/appxyz/service1-db-config|host ==> export SERVICE1_DB_CONFIG__HOST='db.internal'

Alternatively if you are configmanager-ing a file via the fromstr command and the input is something like this:

(YAML)

app:
	name: xyz
db:
	host: AWSSECRETS#/appxyz/service1-db-config|host
	port: AWSSECRETS#/appxyz/service1-db-config|port
	pass: AWSSECRETS#/appxyz/service1-db-config|pass

which would result in this

app:
	name: xyz
db:
	host: db.internal
	port: 3306
	pass: sUp3$ecr3T!

If your config parameter matches the config interface, you can also leave the entire token to point to the db key

app:
	name: xyz
db: AWSSECRETS#/appxyz/service1-db-config

result:

app:
	name: xyz
db: {
 	"host": "db.internal",
	"port": 3306,
	"pass": "sUp3$ecr3T!",
}

Special AZKVSECRETS

For Azure KeyVault the first part of the token needs to be the name of the vault.

Azure Go SDK (v2) requires the vault Uri on initializing the client

AZKVSECRET#/test-vault//token/1 ==> will use KeyVault implementation to retrieve the /token/1 from a test-vault.

AZKVSECRET#/test-vault/no-slash-token-1 ==> will use KeyVault implementation to retrieve the no-slash-token-1 from a test-vault.

Go API

latest api here

Sample Use case

One of the sample use cases includes implementation in a K8s controller.

E.g. your Custom CRD stores some values in plain text that should really be secrets/nonpublic config parameters - something like this can be invoked from inside the controller code using the generator pkg API.

See examples for more examples and tests for sample input/usage

import (
	"context"
	"fmt"

	"github.com/dnitsch/configmanager/pkg/generator"
	"github.com/dnitsch/configmanager"
)

func main() {
	cm := &configmanager.ConfigManager{}
	cnf := generator.NewConfig()
	// JSON Marshal K8s CRD into
	exampleK8sCrdMarshalled := `apiVersion: crd.foo.custom/v1alpha1
kind: CustomFooCrd
metadata:
	name: foo
	namespace: bar
spec:
	name: baz
	secret_val: AWSSECRETS#/customfoo/secret-val
	owner: test_10016@example.com
`
	pm, err := cm.RetrieveWithInputReplaced(exampleK8sCrdMarshalled, *cnf)

	if err != nil {
		panic(err)
	}
	fmt.Println(pm)
}

Above example would ensure that you can safely store config/secret values on a CRD in plain text.

Beware logging out the CRD after tokens have been replaced.

Help

• More implementations should be easily added with a specific implementation under the strategy interface

  • e.g. GCP equivalent

• maybe run as cron in the background to perform a periodic sync in case values change?