[PATCH proxmox-mail-forward 4/5] forward mails on PDM installations as well

[Lukas Wagner <l.wagner@proxmox.com>]

Use the same approach as for PBS installations, namely by storing the
notification in a spool directory which is then later handled by a
worker in the PDM proxy process.

Signed-off-by: Lukas Wagner <l.wagner@proxmox.com>
---
 src/main.rs | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/src/main.rs b/src/main.rs
index 0509cc4..92a2804 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -30,6 +30,10 @@ const PBS_UNPRIV_USER: &str = "backup";
 const PBS_CFG_PATH: &str = "/etc/proxmox-backup";
 const PBS_SPOOL_DIR: &str = "/var/lib/proxmox-backup/notifications/queue";
 
+const PDM_UNPRIV_USER: &str = "www-data";
+const PDM_CFG_PATH: &str = "/etc/proxmox-datacenter-manager";
+const PDM_SPOOL_DIR: &str = "/var/lib/proxmox-datacenter-manager/notifications/queue";
+
 /// Wrapper around `proxmox_sys::fs::file_read_optional_string` which also returns `None` upon error
 /// after logging it.
 fn attempt_file_read<P: AsRef<Path>>(path: P) -> Option<String> {
@@ -81,6 +85,16 @@ fn forward_for_pbs(mail: &[u8]) -> Result<(), Error> {
     forward_via_spooldir(Path::new(PBS_SPOOL_DIR), opts, mail)
 }
 
+/// Forward a mail to PDM's notification system
+fn forward_for_pdm(mail: &[u8]) -> Result<(), Error> {
+    let unpriv_user = lookup_user(PDM_UNPRIV_USER)?;
+    let opts = CreateOptions::new()
+        .owner(unpriv_user.uid)
+        .group(unpriv_user.gid);
+
+    forward_via_spooldir(Path::new(PDM_SPOOL_DIR), opts, mail)
+}
+
 /// Forward the email by queuing it in a spool directory.
 ///
 /// In the product, there is a worker that periodically handles enqueued notifications stored
@@ -136,6 +150,13 @@ fn main() {
                     error!("could not forward mail for Proxmox Backup Server: {err:#}");
                 }
             }
+
+            // Assume a PDM installation if /etc/proxmox-datacenter-manager exists
+            if Path::new(PDM_CFG_PATH).exists() {
+                if let Err(err) = forward_for_pdm(&mail) {
+                    error!("could not forward mail for Proxmox Datacenter Manager: {err:#}");
+                }
+            }
         }
         Err(err) => {
             error!("could not read mail from STDIN: {err:#}")
-- 
2.47.3