| 1 |
|
defmodule WalletIntegrations.SecretProvider do |
| 2 |
|
@moduledoc """ |
| 3 |
|
Behaviour for loading provider credentials at runtime. |
| 4 |
|
|
| 5 |
|
Implementations must never source credentials from plaintext config |
| 6 |
|
files committed to source control (ADR 0006 / ADR 0008). |
| 7 |
|
|
| 8 |
|
## Implementations |
| 9 |
|
- `WalletIntegrations.SecretProvider.EnvSecretProvider` — reads from application env. |
| 10 |
|
Suitable for development, CI, and secrets-manager-injected env (e.g. AWS SSM, Vault sidecar). |
| 11 |
|
""" |
| 12 |
|
|
| 13 |
|
@callback get_secret(key :: atom()) :: {:ok, String.t()} | {:error, :secret_not_found} |
| 14 |
|
|
| 15 |
|
@doc "Resolve the configured secret provider module." |
| 16 |
|
@spec provider() :: module() |
| 17 |
|
def provider do |
| 18 |
|
Application.get_env( |
| 19 |
|
:wallet_integrations, |
| 20 |
|
:secret_provider, |
| 21 |
|
WalletIntegrations.SecretProvider.EnvSecretProvider |
| 22 |
|
) |
| 23 |
|
end |
| 24 |
|
|
| 25 |
|
@doc "Convenience: fetch a secret via the configured provider." |
| 26 |
|
@spec get(key :: atom()) :: {:ok, String.t()} | {:error, :secret_not_found} |
| 27 |
|
def get(key) do |
| 28 |
|
apply(provider(), :get_secret, [key]) |
| 29 |
|
end |
| 30 |
|
end |
| 31 |
|
|
| 32 |
|
defmodule WalletIntegrations.SecretProvider.EnvSecretProvider do |
| 33 |
|
@moduledoc """ |
| 34 |
|
Application-env-backed secret provider. |
| 35 |
|
|
| 36 |
|
In production, these values should be injected by a secrets manager |
| 37 |
|
(e.g. AWS SSM Parameter Store, HashiCorp Vault sidecar agent) and never |
| 38 |
|
hardcoded in config files. |
| 39 |
|
|
| 40 |
|
Keys used: |
| 41 |
|
- `:stripe_secret_key` — Stripe API secret key (sk_test_... or sk_live_...) |
| 42 |
|
- `:stripe_webhook_secret` — Stripe webhook signing secret (whsec_...) |
| 43 |
|
""" |
| 44 |
|
|
| 45 |
|
@behaviour WalletIntegrations.SecretProvider |
| 46 |
|
|
| 47 |
|
@impl true |
| 48 |
|
def get_secret(key) do |
| 49 |
11 |
case Application.get_env(:wallet_integrations, key) do |
| 50 |
7 |
nil -> {:error, :secret_not_found} |
| 51 |
4 |
value when is_binary(value) -> {:ok, value} |
| 52 |
:-( |
_ -> {:error, :secret_not_found} |
| 53 |
|
end |
| 54 |
|
end |
| 55 |
|
end |