bottomless-cli: added snapshot command

bottomless-cli/src/main.rs

@@ -106,6 +106,11 @@ enum Commands {
  #[clap(long, short)]
  verbose: bool,
  },
+ #[clap(about = "Generate and upload a snapshot for a given generation or timestamp")]
+ Snapshot {
+ #[clap(long, short)]
+ generation: Option<uuid::Uuid>,
+ },
 }
 
 async fn run() -> Result<()> {
@@ -273,6 +278,44 @@ async fn run() -> Result<()> {
  "rm command cannot be run without parameters; see -h or --help for details"
  ),
  },
+ Commands::Snapshot { generation } => {
+ tokio::fs::create_dir_all(&database_dir).await?;
+ let generation = if let Some(gen) = generation {
+ gen
+ } else if let Some(gen) = client.latest_generation_before(None).await {
+ gen
+ } else {
+ println!("no generation to snapshot found; nothing to do");
+ return Ok(());
+ };
+ // snapshots mark the state of the DB at the beginning of the generation, therefore
+ // snapshot at generation N is a final state of database at generation N-1. This can
+ // be later used for fast restore: restore from generation N = snapshot + all WAL frames
+ // from that generation.
+ let parent = if let Some(parent) = client.get_dependency(&generation).await? {
+ parent
+ } else {
+ println!("cannot create a snapshot at the beginning of the generation {}: parent generation not found", generation);
+ return Ok(());
+ };
+ client.restore(Some(parent.clone()), None).await?;
+ println!(
+ "restored database at the start of generation {}: preparing snapshot...",
+ generation
+ );
+ let db_path = PathBuf::from(&database);
+ if let Err(e) = verify_db(&db_path) {
+ println!("Verification failed: {e}");
+ std::process::exit(1)
+ } else {
+ println!("verification succeeded");
+ client.set_generation(generation.clone());
+ client.snapshot_main_db_file(true).await?;
+ client.wait_until_snapshotted().await?;
+ println!("snapshot uploaded for generation: {}", generation);
+ tokio::fs::remove_dir_all(&database_dir).await?;
+ }
+ }
  };
  Ok(())
 }