From 2ef51f7df965dd8386db00d2b2b759fbe6d5f1c6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Cl=C3=A9ment=20Renault?= <clement@meilisearch.com>
Date: Fri, 18 Oct 2019 12:52:45 +0200
Subject: [PATCH] Introduce a function to copy and compact a database env

---
 meilidb-core/examples/from_file.rs | 9 +++++++++
 meilidb-core/src/database.rs       | 6 ++++++
 2 files changed, 15 insertions(+)

diff --git a/meilidb-core/examples/from_file.rs b/meilidb-core/examples/from_file.rs
index e00ff94f0..981f294ff 100644
--- a/meilidb-core/examples/from_file.rs
+++ b/meilidb-core/examples/from_file.rs
@@ -33,6 +33,9 @@ struct IndexCommand {
 
     #[structopt(long)]
     update_group_size: Option<usize>,
+
+    #[structopt(long, parse(from_os_str))]
+    compact_to_path: Option<PathBuf>,
 }
 
 #[derive(Debug, StructOpt)]
@@ -165,6 +168,12 @@ fn index_command(command: IndexCommand, database: Database) -> Result<(), Box<dy
 
     println!("database created in {:.2?} at: {:?}", start.elapsed(), command.database_path);
 
+    if let Some(path) = command.compact_to_path {
+        let start = Instant::now();
+        let _file = database.copy_and_compact_to_path(&path)?;
+        println!("database compacted in {:.2?} at: {:?}", start.elapsed(), path);
+    }
+
     Ok(())
 }
 
diff --git a/meilidb-core/src/database.rs b/meilidb-core/src/database.rs
index f5ae46347..035b7e7a4 100644
--- a/meilidb-core/src/database.rs
+++ b/meilidb-core/src/database.rs
@@ -1,8 +1,10 @@
 use std::collections::hash_map::{HashMap, Entry};
+use std::fs::File;
 use std::path::Path;
 use std::sync::{Arc, RwLock};
 use std::{fs, thread};
 
+use zlmdb::{Result as ZResult, CompactionOption};
 use zlmdb::types::{Str, Unit};
 use crossbeam_channel::Receiver;
 use log::{debug, error};
@@ -163,6 +165,10 @@ impl Database {
         }
     }
 
+    pub fn copy_and_compact_to_path<P: AsRef<Path>>(&self, path: P) -> ZResult<File> {
+        self.env.copy_to_path(path, CompactionOption::Enabled)
+    }
+
     pub fn indexes_names(&self) -> MResult<Vec<String>> {
         let indexes = self.indexes.read().unwrap();
         Ok(indexes.keys().cloned().collect())