[pbs-devel] [PATCH backup v2 2/7] pbs-client: add helper for getting UTF-8 secrets

[Maximiliano Sandoval]

We are going to add more credentials so it makes sense to have a common
helper to get the secrets.

Signed-off-by: Maximiliano Sandoval <m.sandoval at proxmox.com>
---
 pbs-client/src/tools/mod.rs | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/pbs-client/src/tools/mod.rs b/pbs-client/src/tools/mod.rs
index a42fa114..efd2e139 100644
--- a/pbs-client/src/tools/mod.rs
+++ b/pbs-client/src/tools/mod.rs
@@ -153,6 +153,25 @@ fn get_secret_from_env(base_name: &str) -> Result<Option<String>, Error> {
     Ok(None)
 }
 
+/// Gets a secret or value from the environment.
+///
+/// Checks for an environment variable named `env_variable`, and if missing, it
+/// checks for a system [credential] named `credential_name`. Assumes the secret
+/// is UTF-8 encoded.
+///
+/// [credential]: https://systemd.io/CREDENTIALS/
+fn get_secret_impl(env_variable: &str, credential_name: &str) -> Result<Option<String>, Error> {
+    if let Some(password) = get_secret_from_env(env_variable)? {
+        Ok(Some(password))
+    } else if let Some(password) = get_credential(credential_name)? {
+        String::from_utf8(password)
+            .map(Option::Some)
+            .map_err(|_err| format_err!("credential {credential_name} is not utf8 encoded"))
+    } else {
+        Ok(None)
+    }
+}
+
 /// Gets the backup server's password.
 ///
 /// Looks for a password in the `PBS_PASSWORD` environment variable, if there
-- 
2.39.5