1 files changed, 113 insertions, 0 deletions
diff --git a/src/cmd/drop/bundles/prune.rs b/src/cmd/drop/bundles/prune.rs
new file mode 100644
index 0000000..6bd984d
--- /dev/null
+++ b/src/cmd/drop/bundles/prune.rs
@@ -0,0 +1,113 @@
+// Copyright © 2022 Kim Altintop <kim@eagain.io>
+// SPDX-License-Identifier: GPL-2.0-only WITH openvpn-openssl-exception
+
+use std::{
+    collections::BTreeSet,
+    fs,
+    path::PathBuf,
+    str::FromStr,
+};
+
+use clap::ValueHint;
+
+use crate::{
+    bundle,
+    cfg,
+    cmd::{
+        self,
+        ui::{
+            info,
+            warn,
+        },
+    },
+    git,
+    patches::iter::dropped,
+};
+
+// TODO:
+//
+// - option to prune bundles made obsolete by snapshots
+
+#[derive(Debug, clap::Args)]
+pub struct Prune {
+    /// Path to the drop repository
+    #[clap(from_global)]
+    git_dir: PathBuf,
+    /// The directory where to write the bundle to
+    ///
+    /// Unless this is an absolute path, it is treated as relative to $GIT_DIR.
+    #[clap(
+        long,
+        value_parser,
+        value_name = "DIR",
+        default_value_os_t = cfg::paths::bundles().to_owned(),
+        value_hint = ValueHint::DirPath,
+    )]
+    bundle_dir: PathBuf,
+    /// Name of a git ref holding the drop metadata history
+    ///
+    /// All locally tracked drops should be given, otherwise bundles might get
+    /// pruned which are still being referred to.
+    #[clap(long = "drop", value_parser, value_name = "REF")]
+    drop_refs: Vec<String>,
+    /// Pretend to unlink, but don't
+    #[clap(long, value_parser)]
+    dry_run: bool,
+    /// Also remove location files (.uris)
+    #[clap(long, value_parser)]
+    remove_locations: bool,
+}
+
+pub fn prune(args: Prune) -> cmd::Result<Vec<bundle::Hash>> {
+    let repo = git::repo::open_bare(&args.git_dir)?;
+    let bundle_dir = if args.bundle_dir.is_relative() {
+        repo.path().join(args.bundle_dir)
+    } else {
+        args.bundle_dir
+    };
+
+    let mut seen = BTreeSet::new();
+    for short in &args.drop_refs {
+        let drop_ref = repo.resolve_reference_from_short_name(short)?;
+        let ref_name = drop_ref.name().expect("drop references to be valid utf8");
+        info!("Collecting bundle hashes from {ref_name} ...");
+        for record in dropped::records(&repo, ref_name) {
+            let record = record?;
+            seen.insert(*record.bundle_hash());
+        }
+    }
+
+    info!("Traversing bundle dir {} ...", bundle_dir.display());
+    let mut pruned = Vec::new();
+    for entry in fs::read_dir(&bundle_dir)? {
+        let entry = entry?;
+        let path = entry.path();
+        match path.extension() {
+            Some(ext) if ext == bundle::FILE_EXTENSION => {
+                let name = path.file_stem();
+                match name
+                    .and_then(|n| n.to_str())
+                    .and_then(|s| bundle::Hash::from_str(s).ok())
+                {
+                    Some(hash) => {
+                        if !seen.contains(&hash) {
+                            if !args.dry_run {
+                                fs::remove_file(&path)?;
+                            }
+                            pruned.push(hash);
+                        }
+                    },
+                    None => warn!("Ignoring {}: file name not a bundle hash", path.display()),
+                }
+            },
+            Some(ext) if ext == bundle::list::FILE_EXTENSION => {
+                if args.remove_locations {
+                    fs::remove_file(&path)?;
+                }
+            },
+            _ => warn!("Ignoring {}: missing .bundle", path.display()),
+        }
+    }
+
+    Ok(pruned)
+}