add systemd configuration file parser/writer, start job configuration

src/config/jobs.rs

@@ -0,0 +1,173 @@
+use anyhow::{bail, Error};
+use regex::Regex;
+use lazy_static::lazy_static;
+
+use proxmox::api::section_config::SectionConfigData;
+use proxmox::tools::{fs::replace_file, fs::CreateOptions};
+
+use crate::PROXMOX_SAFE_ID_REGEX_STR;
+use crate::tools::systemd::parser::*;
+use crate::tools::systemd::types::*;
+
+const SYSTEMD_CONFIG_DIR: &str = "/etc/systemd/system";
+
+#[derive(Debug)]
+pub enum JobType {
+    GarbageCollection,
+    Prune,
+}
+
+#[derive(Debug)]
+pub struct CalenderTimeSpec {
+    pub hour: u8, // 0-23
+}
+
+#[derive(Debug)]
+pub struct JobListEntry {
+    job_type: JobType,
+    id: String,
+}
+
+pub fn list_jobs() -> Result<Vec<JobListEntry>, Error> {
+
+    lazy_static!{
+        static ref PBS_JOB_REGEX: Regex = Regex::new(
+            concat!(r"^pbs-(gc|prune)-(", PROXMOX_SAFE_ID_REGEX_STR!(), ").timer$")
+        ).unwrap();
+    }
+
+    let mut list = Vec::new();
+
+    for entry in crate::tools::fs::read_subdir(libc::AT_FDCWD, SYSTEMD_CONFIG_DIR)? {
+        let entry = entry?;
+        let file_type = match entry.file_type() {
+            Some(file_type) => file_type,
+            None => bail!("unable to detect file type"),
+        };
+        if file_type != nix::dir::Type::File { continue; };
+
+        let file_name = entry.file_name().to_bytes();
+        if file_name == b"." || file_name == b".." { continue; };
+
+        let name = match std::str::from_utf8(file_name) {
+            Ok(name) => name,
+            Err(_) => continue,
+        };
+        let caps = match PBS_JOB_REGEX.captures(name) {
+            Some(caps) => caps,
+            None => continue,
+        };
+
+        // fixme: read config data ?
+        //let config = parse_systemd_config(&format!("{}/{}", SYSTEMD_CONFIG_DIR, name))?;
+
+        match (&caps[1], &caps[2]) {
+            ("gc", store) => {
+                list.push(JobListEntry {
+                    job_type: JobType::GarbageCollection,
+                    id: store.to_string(),
+                });
+            }
+            ("prune", store) => {
+                list.push(JobListEntry {
+                    job_type: JobType::Prune,
+                    id: store.to_string(),
+                });
+            }
+            _ => unreachable!(),
+        }
+    }
+
+    Ok(list)
+}
+
+pub fn new_systemd_service_config(
+    unit: &SystemdUnitSection,
+    service: &SystemdServiceSection,
+) -> Result<SectionConfigData, Error> {
+
+    let mut config = SectionConfigData::new();
+    config.set_data("Unit", "Unit", unit)?;
+    config.record_order("Unit");
+    config.set_data("Service", "Service", service)?;
+    config.record_order("Service");
+
+    Ok(config)
+}
+
+pub fn new_systemd_timer_config(
+    unit: &SystemdUnitSection,
+    timer: &SystemdTimerSection,
+    install:  &SystemdInstallSection,
+) -> Result<SectionConfigData, Error> {
+
+    let mut config = SectionConfigData::new();
+    config.set_data("Unit", "Unit", unit)?;
+    config.record_order("Unit");
+    config.set_data("Timer", "Timer", timer)?;
+    config.record_order("Timer");
+    config.set_data("Install", "Install", install)?;
+    config.record_order("Install");
+
+    Ok(config)
+}
+
+pub fn create_garbage_collection_job(
+    schedule: CalenderTimeSpec,
+    store: &str,
+) -> Result<(), Error> {
+
+    if schedule.hour > 23 {
+        bail!("inavlid time spec: hour > 23");
+    }
+
+    let description = format!("Proxmox Backup Server Garbage Collection Job '{}'", store);
+
+    let unit = SystemdUnitSection {
+        Description: description.clone(),
+        ConditionACPower: Some(true),
+        ..Default::default()
+    };
+
+    let cmd = format!("/usr/sbin/proxmox-backup-manager garbage-collection start {} --output-format json", store);
+    let service = SystemdServiceSection {
+        Type: Some(ServiceStartup::Oneshot),
+        ExecStart: Some(vec![cmd]),
+        ..Default::default()
+    };
+
+    let service_config = new_systemd_service_config(&unit, &service)?;
+
+    let timer = SystemdTimerSection {
+        OnCalendar: Some(vec![format!("{}:00", schedule.hour)]),
+        ..Default::default()
+    };
+
+    let install = SystemdInstallSection {
+        WantedBy: Some(vec![String::from("timers.target")]),
+        ..Default::default()
+    };
+
+    let timer_config = new_systemd_timer_config(&unit, &timer, &install)?;
+
+    let basename = format!("{}/pbs-gc-{}", SYSTEMD_CONFIG_DIR, store);
+    let timer_fn = format!("{}.timer", basename);
+    let timer_config = CONFIG.write(&timer_fn, &timer_config)?;
+
+    let service_fn = format!("{}.service", basename);
+    let service_config = CONFIG.write(&service_fn, &service_config)?;
+
+    let backup_user = crate::backup::backup_user()?;
+    let mode = nix::sys::stat::Mode::from_bits_truncate(0o0750);
+    // set the correct owner/group/permissions while saving file
+    // owner(rw) = root, group(r)= backup
+    let options = CreateOptions::new()
+        .perm(mode)
+        .owner(nix::unistd::ROOT)
+        .group(backup_user.gid);
+
+    replace_file(service_fn, service_config.as_bytes(), options.clone())?;
+    replace_file(timer_fn, timer_config.as_bytes(), options)?;
+
+    Ok(())
+}