// Copyright (c) 2022-2023 Niko Bonnieure, Par le Peuple, NextGraph.org developers // All rights reserved. // Licensed under the Apache License, Version 2.0 // // or the MIT license , // at your option. All files in the project carrying such // notice may not be copied, modified, or distributed except // according to those terms. use p2p_repo::store::*; use p2p_repo::types::*; use p2p_repo::utils::*; use debug_print::*; use std::path::Path; use std::sync::{Arc, RwLock}; use rkv::backend::{ BackendDatabaseFlags, BackendFlags, BackendIter, BackendWriteFlags, DatabaseFlags, Lmdb, LmdbDatabase, LmdbDatabaseFlags, LmdbEnvironment, LmdbRwTransaction, LmdbWriteFlags, }; use rkv::{ Manager, MultiIntegerStore, Rkv, SingleStore, StoreError, StoreOptions, Value, WriteFlags, Writer, }; use serde::{Deserialize, Serialize}; use serde_bare::error::Error; #[derive(Debug)] pub struct LmdbRepoStore { /// the main store where all the repo blocks are stored main_store: SingleStore, /// store for the pin boolean, recently_used timestamp, and synced boolean meta_store: SingleStore, /// store for the expiry timestamp expiry_store: MultiIntegerStore, /// store for the LRU list recently_used_store: MultiIntegerStore, /// the opened environment so we can create new transactions environment: Arc>>, } // TODO: versioning V0 #[derive(Clone, Debug, Serialize, Deserialize, PartialEq)] struct BlockMeta { pub pin: bool, pub last_used: Timestamp, pub synced: bool, } impl RepoStore for LmdbRepoStore { /// Retrieves a block from the storage backend. fn get(&self, block_id: &BlockId) -> Result { let lock = self.environment.read().unwrap(); let reader = lock.read().unwrap(); let block_id_ser = serde_bare::to_vec(&block_id).unwrap(); let block_ser_res = self.main_store.get(&reader, block_id_ser.clone()); match block_ser_res { Err(e) => Err(StorageError::BackendError), Ok(None) => Err(StorageError::NotFound), Ok(Some(block_ser)) => { // updating recently_used // first getting the meta for this BlockId let meta_ser = self.meta_store.get(&reader, block_id_ser.clone()).unwrap(); match meta_ser { Some(meta_value) => { let mut meta = serde_bare::from_slice::(&meta_value.to_bytes().unwrap()) .unwrap(); if meta.synced { let mut writer = lock.write().unwrap(); let now = now_timestamp(); if !meta.pin { // we remove the previous timestamp (last_used) from recently_used_store self.remove_from_lru(&mut writer, &block_id_ser, &meta.last_used) .unwrap(); // we add an entry to recently_used_store with now self.add_to_lru(&mut writer, &block_id_ser, &now).unwrap(); } // we save the new meta (with last_used:now) meta.last_used = now; let new_meta_ser = serde_bare::to_vec(&meta).unwrap(); self.meta_store .put( &mut writer, block_id_ser, &Value::Blob(new_meta_ser.as_slice()), ) .unwrap(); // commit writer.commit().unwrap(); } } _ => {} // there is no meta. we do nothing since we start to record LRU only once synced == true. } match serde_bare::from_slice::(&block_ser.to_bytes().unwrap()) { Err(_e) => Err(StorageError::InvalidValue), Ok(o) => { if o.id() != *block_id { debug_println!( "Invalid ObjectId.\nExp: {:?}\nGot: {:?}\nContent: {:?}", block_id, o.id(), o ); panic!("CORRUPTION OF DATA !"); } Ok(o) } } } } } /// Adds a block in the storage backend. /// The block is persisted to disk. /// Returns the BlockId of the Block. fn put(&self, block: &Block) -> Result { let block_ser = serde_bare::to_vec(&block).unwrap(); let block_id = block.id(); let block_id_ser = serde_bare::to_vec(&block_id).unwrap(); let lock = self.environment.read().unwrap(); let mut writer = lock.write().unwrap(); // TODO: check if the block is already in store? if yes, don't put it again. // I didnt do it yet because it is extra cost. surely a get on the store is lighter than a put // but doing a get in additing to a put for every call, is probably even costlier. better to deal with that at the higher level self.main_store .put( &mut writer, &block_id_ser, &Value::Blob(block_ser.as_slice()), ) .unwrap(); // if it has an expiry, adding the BlockId to the expiry_store match block.expiry() { Some(expiry) => { self.expiry_store .put(&mut writer, expiry, &Value::Blob(block_id_ser.as_slice())) .unwrap(); } _ => {} } writer.commit().unwrap(); Ok(block_id) } /// Removes the block from the storage backend. /// The removed block is returned, so it can be inspected. /// Also returned is the approximate size of of free space that was reclaimed. fn del(&self, block_id: &BlockId) -> Result<(Block, usize), StorageError> { let lock = self.environment.read().unwrap(); let mut writer = lock.write().unwrap(); let block_id_ser = serde_bare::to_vec(&block_id).unwrap(); // retrieving the block itself (we need the expiry) let block_ser = self .main_store .get(&writer, block_id_ser.clone()) .unwrap() .ok_or(StorageError::NotFound)?; let slice = block_ser.to_bytes().unwrap(); let block = serde_bare::from_slice::(&slice).unwrap(); //FIXME propagate error? let meta_res = self.meta_store.get(&writer, block_id_ser.clone()).unwrap(); if meta_res.is_some() { let meta = serde_bare::from_slice::(&meta_res.unwrap().to_bytes().unwrap()) .unwrap(); if meta.last_used != 0 { self.remove_from_lru(&mut writer, &block_id_ser.clone(), &meta.last_used) .unwrap(); } // removing the meta self.meta_store .delete(&mut writer, block_id_ser.clone()) .unwrap(); } // delete block from main_store self.main_store .delete(&mut writer, block_id_ser.clone()) .unwrap(); // remove BlockId from expiry_store, if any expiry match block.expiry() { Some(expiry) => { self.expiry_store .delete( &mut writer, expiry, &Value::Blob(block_id_ser.clone().as_slice()), ) .unwrap(); } _ => {} } writer.commit().unwrap(); Ok((block, slice.len())) } } impl LmdbRepoStore { /// Opens the store and returns a RepoStore object that should be kept and used to call put/get/delete/pin /// The key is the encryption key for the data at rest. pub fn open<'a>(path: &Path, key: [u8; 32]) -> LmdbRepoStore { let mut manager = Manager::::singleton().write().unwrap(); let shared_rkv = manager .get_or_create(path, |path| { //Rkv::new::(path) // use this instead to disable encryption Rkv::with_encryption_key_and_mapsize::(path, key, 2 * 1024 * 1024 * 1024) }) .unwrap(); let env = shared_rkv.read().unwrap(); println!( "created env with LMDB Version: {} key: {}", env.version(), hex::encode(&key) ); let main_store = env.open_single("main", StoreOptions::create()).unwrap(); let meta_store = env.open_single("meta", StoreOptions::create()).unwrap(); let mut opts = StoreOptions::::create(); opts.flags.set(DatabaseFlags::DUP_FIXED, true); let expiry_store = env.open_multi_integer("expiry", opts).unwrap(); let recently_used_store = env.open_multi_integer("recently_used", opts).unwrap(); LmdbRepoStore { environment: shared_rkv.clone(), main_store, meta_store, expiry_store, recently_used_store, } } //FIXME: use BlockId, not ObjectId. this is a block level operation /// Pins the object pub fn pin(&self, object_id: &ObjectId) -> Result<(), StorageError> { self.set_pin(object_id, true) } //FIXME: use BlockId, not ObjectId. this is a block level operation /// Unpins the object pub fn unpin(&self, object_id: &ObjectId) -> Result<(), StorageError> { self.set_pin(object_id, false) } //FIXME: use BlockId, not ObjectId. this is a block level operation /// Sets the pin for that Object. if add is true, will add the pin. if false, will remove the pin. /// A pin on an object prevents it from being removed when the store is making some disk space by using the LRU. /// A pin does not override the expiry. If expiry is set and is reached, the obejct will be deleted, no matter what. pub fn set_pin(&self, object_id: &ObjectId, add: bool) -> Result<(), StorageError> { let lock = self.environment.read().unwrap(); let mut writer = lock.write().unwrap(); let obj_id_ser = serde_bare::to_vec(&object_id).unwrap(); let meta_ser = self.meta_store.get(&writer, &obj_id_ser).unwrap(); let mut meta; // if adding a pin, if there is a meta (if already pinned, return) and is synced, remove the last_used timestamp from recently_used_store // if no meta, create it with pin:true, synced: false // if removing a pin (if pin already removed, return), if synced, add an entry to recently_used_store with the last_used timestamp (as found in meta, dont use now) match meta_ser { Some(meta_value) => { meta = serde_bare::from_slice::(&meta_value.to_bytes().unwrap()).unwrap(); if add == meta.pin { // pinning while already pinned, or unpinning while already unpinned. NOP return Ok(()); }; meta.pin = add; if meta.synced { if add { // we remove the previous timestamp (last_used) from recently_used_store self.remove_from_lru(&mut writer, &obj_id_ser, &meta.last_used) .unwrap(); } else { // we add an entry to recently_used_store with last_used self.add_to_lru(&mut writer, &obj_id_ser, &meta.last_used) .unwrap(); } } } None => { if add { meta = BlockMeta { pin: true, synced: false, last_used: 0, } } else { // there is no meta, and user wants to unpin, so let's leave everything as it is. return Ok(()); } } } let new_meta_ser = serde_bare::to_vec(&meta).unwrap(); self.meta_store .put( &mut writer, obj_id_ser, &Value::Blob(new_meta_ser.as_slice()), ) .unwrap(); // commit writer.commit().unwrap(); Ok(()) } //FIXME: use BlockId, not ObjectId. this is a block level operation /// the broker calls this method when the block has been retrieved/synced by enough peers and it /// can now be included in the LRU for potential garbage collection. /// If this method has not been called on a block, it will be kept in the store and will not enter LRU. pub fn has_been_synced(&self, block_id: &BlockId, when: Option) -> Result<(), Error> { let lock = self.environment.read().unwrap(); let mut writer = lock.write().unwrap(); let block_id_ser = serde_bare::to_vec(&block_id).unwrap(); let meta_ser = self.meta_store.get(&writer, block_id_ser.clone()).unwrap(); let mut meta; let now = match when { None => now_timestamp(), Some(w) => w, }; // get the meta. if no meta, it is ok, we will create it after (with pin:false and synced:true) // if already synced, return // update the meta with last_used:now and synced:true // if pinned, save and return // otherwise add an entry to recently_used_store with now match meta_ser { Some(meta_value) => { meta = serde_bare::from_slice::(&meta_value.to_bytes().unwrap()).unwrap(); if meta.synced { // already synced. NOP return Ok(()); }; meta.synced = true; meta.last_used = now; if !meta.pin { // we add an entry to recently_used_store with now println!("adding to LRU"); self.add_to_lru(&mut writer, &block_id_ser, &now).unwrap(); } } None => { meta = BlockMeta { pin: false, synced: true, last_used: now, }; println!("adding to LRU also"); self.add_to_lru(&mut writer, &block_id_ser, &now).unwrap(); } } let new_meta_ser = serde_bare::to_vec(&meta).unwrap(); self.meta_store .put( &mut writer, block_id_ser, &Value::Blob(new_meta_ser.as_slice()), ) .unwrap(); // commit writer.commit().unwrap(); Ok(()) } /// Removes all the blocks that have expired. /// The broker should call this method periodically. pub fn remove_expired(&self) -> Result<(), Error> { let mut block_ids: Vec = vec![]; { let lock = self.environment.read().unwrap(); let reader = lock.read().unwrap(); let mut iter = self .expiry_store .iter_prev_dup_from(&reader, now_timestamp()) .unwrap(); while let Some(Ok(mut sub_iter)) = iter.next() { while let Some(Ok(k)) = sub_iter.next() { //println!("removing {:?} {:?}", k.0, k.1); let block_id = serde_bare::from_slice::(k.1).unwrap(); block_ids.push(block_id); } } } for block_id in block_ids { self.del(&block_id).unwrap(); } Ok(()) } /// Removes some blocks that haven't been used for a while, reclaiming some space on disk. /// The oldest are removed first, until the total amount of data removed is at least equal to size, /// or the LRU list became empty. The approximate size of the storage space that was reclaimed is returned. pub fn remove_least_used(&self, size: usize) -> usize { let mut block_ids: Vec = vec![]; let mut total: usize = 0; { let lock = self.environment.read().unwrap(); let reader = lock.read().unwrap(); let mut iter = self.recently_used_store.iter_start(&reader).unwrap(); while let Some(Ok(entry)) = iter.next() { let block_id = serde_bare::from_slice::(entry.1.to_bytes().unwrap().as_slice()) .unwrap(); block_ids.push(block_id); } } for block_id in block_ids { let (block, block_size) = self.del(&block_id).unwrap(); println!("removed {:?}", block_id); total += block_size; if total >= size { break; } } total } fn remove_from_lru( &self, writer: &mut Writer, block_id_ser: &Vec, time: &Timestamp, ) -> Result<(), StoreError> { self.recently_used_store .delete(writer, *time, &Value::Blob(block_id_ser.as_slice())) } fn add_to_lru( &self, writer: &mut Writer, block_id_ser: &Vec, time: &Timestamp, ) -> Result<(), StoreError> { let mut flag = LmdbWriteFlags::empty(); flag.set(WriteFlags::APPEND_DUP, true); self.recently_used_store.put_with_flags( writer, *time, &Value::Blob(block_id_ser.as_slice()), flag, ) } fn list_all(&self) { let lock = self.environment.read().unwrap(); let reader = lock.read().unwrap(); println!("MAIN"); let mut iter = self.main_store.iter_start(&reader).unwrap(); while let Some(Ok(entry)) = iter.next() { println!("{:?} {:?}", entry.0, entry.1) } println!("META"); let mut iter2 = self.meta_store.iter_start(&reader).unwrap(); while let Some(Ok(entry)) = iter2.next() { println!("{:?} {:?}", entry.0, entry.1) } println!("EXPIRY"); let mut iter3 = self.expiry_store.iter_start(&reader).unwrap(); while let Some(Ok(entry)) = iter3.next() { println!("{:?} {:?}", entry.0, entry.1) } println!("LRU"); let mut iter4 = self.recently_used_store.iter_start(&reader).unwrap(); while let Some(Ok(entry)) = iter4.next() { println!("{:?} {:?}", entry.0, entry.1) } } } #[cfg(test)] mod test { use crate::repo_store::LmdbRepoStore; use p2p_repo::store::*; use p2p_repo::types::*; use p2p_repo::utils::*; use rkv::backend::{BackendInfo, BackendStat, Lmdb, LmdbEnvironment}; use rkv::{Manager, Rkv, StoreOptions, Value}; #[allow(unused_imports)] use std::time::Duration; #[allow(unused_imports)] use std::{fs, thread}; use tempfile::Builder; #[test] pub fn test_remove_least_used() { let path_str = "test-env"; let root = Builder::new().prefix(path_str).tempdir().unwrap(); let key: [u8; 32] = [0; 32]; fs::create_dir_all(root.path()).unwrap(); println!("{}", root.path().to_str().unwrap()); let mut store = LmdbRepoStore::open(root.path(), key); let mut now = now_timestamp(); now -= 200; // TODO: fix the LMDB bug that is triggered with x max set to 86 !!! for x in 1..85 { let block = Block::new( Vec::new(), ObjectDeps::ObjectIdList(Vec::new()), None, vec![x; 10], None, ); let block_id = store.put(&block).unwrap(); println!("#{} -> objId {:?}", x, block_id); store .has_been_synced(&block_id, Some(now + x as u32)) .unwrap(); } let ret = store.remove_least_used(200); println!("removed {}", ret); assert_eq!(ret, 208) //store.list_all(); } #[test] pub fn test_set_pin() { let path_str = "test-env"; let root = Builder::new().prefix(path_str).tempdir().unwrap(); let key: [u8; 32] = [0; 32]; fs::create_dir_all(root.path()).unwrap(); println!("{}", root.path().to_str().unwrap()); let mut store = LmdbRepoStore::open(root.path(), key); let mut now = now_timestamp(); now -= 200; // TODO: fix the LMDB bug that is triggered with x max set to 86 !!! for x in 1..100 { let block = Block::new( Vec::new(), ObjectDeps::ObjectIdList(Vec::new()), None, vec![x; 10], None, ); let obj_id = store.put(&block).unwrap(); println!("#{} -> objId {:?}", x, obj_id); store.set_pin(&obj_id, true).unwrap(); store .has_been_synced(&obj_id, Some(now + x as u32)) .unwrap(); } let ret = store.remove_least_used(200); println!("removed {}", ret); assert_eq!(ret, 0); store.list_all(); } #[test] pub fn test_get_valid_value_size() { assert_eq!(store_valid_value_size(0), 4072); assert_eq!(store_valid_value_size(2), 4072); assert_eq!(store_valid_value_size(4072), 4072); assert_eq!(store_valid_value_size(4072 + 1), 4072 + 4096); assert_eq!(store_valid_value_size(4072 + 4096), 4072 + 4096); assert_eq!(store_valid_value_size(4072 + 4096 + 1), 4072 + 4096 + 4096); assert_eq!( store_valid_value_size(4072 + 4096 + 4096), 4072 + 4096 + 4096 ); assert_eq!( store_valid_value_size(4072 + 4096 + 4096 + 1), 4072 + 4096 + 4096 + 4096 ); assert_eq!(store_valid_value_size(4072 + 4096 * 511), 4072 + 4096 * 511); assert_eq!( store_valid_value_size(4072 + 4096 * 511 + 1), 4072 + 4096 * 511 ); } #[test] pub fn test_remove_expired() { let path_str = "test-env"; let root = Builder::new().prefix(path_str).tempdir().unwrap(); let key: [u8; 32] = [0; 32]; fs::create_dir_all(root.path()).unwrap(); println!("{}", root.path().to_str().unwrap()); let mut store = LmdbRepoStore::open(root.path(), key); let now = now_timestamp(); let list = [ now - 10, now - 6, now - 6, now - 3, now - 2, now - 1, //#5 should be removed, and above now + 3, now + 4, now + 4, now + 5, now + 10, ]; let mut block_ids: Vec = Vec::with_capacity(11); println!("now {}", now); let mut i = 0u8; for expiry in list { //let i: u8 = (expiry + 10 - now).try_into().unwrap(); let block = Block::new( Vec::new(), ObjectDeps::ObjectIdList(Vec::new()), Some(expiry), [i].to_vec(), None, ); let block_id = store.put(&block).unwrap(); println!("#{} -> objId {:?}", i, block_id); block_ids.push(block_id); i += 1; } store.remove_expired().unwrap(); assert!(store.get(block_ids.get(0).unwrap()).is_err()); assert!(store.get(block_ids.get(1).unwrap()).is_err()); assert!(store.get(block_ids.get(2).unwrap()).is_err()); assert!(store.get(block_ids.get(5).unwrap()).is_err()); assert!(store.get(block_ids.get(6).unwrap()).is_ok()); assert!(store.get(block_ids.get(7).unwrap()).is_ok()); //store.list_all(); } #[test] pub fn test_remove_all_expired() { let path_str = "test-env"; let root = Builder::new().prefix(path_str).tempdir().unwrap(); let key: [u8; 32] = [0; 32]; fs::create_dir_all(root.path()).unwrap(); println!("{}", root.path().to_str().unwrap()); let mut store = LmdbRepoStore::open(root.path(), key); let now = now_timestamp(); let list = [ now - 10, now - 6, now - 6, now - 3, now - 2, now - 2, //#5 should be removed, and above ]; let mut block_ids: Vec = Vec::with_capacity(6); println!("now {}", now); let mut i = 0u8; for expiry in list { //let i: u8 = (expiry + 10 - now).try_into().unwrap(); let block = Block::new( Vec::new(), ObjectDeps::ObjectIdList(Vec::new()), Some(expiry), [i].to_vec(), None, ); let block_id = store.put(&block).unwrap(); println!("#{} -> objId {:?}", i, block_id); block_ids.push(block_id); i += 1; } store.remove_expired().unwrap(); assert!(store.get(block_ids.get(0).unwrap()).is_err()); assert!(store.get(block_ids.get(1).unwrap()).is_err()); assert!(store.get(block_ids.get(2).unwrap()).is_err()); assert!(store.get(block_ids.get(3).unwrap()).is_err()); assert!(store.get(block_ids.get(4).unwrap()).is_err()); assert!(store.get(block_ids.get(5).unwrap()).is_err()); } #[test] pub fn test_remove_empty_expired() { let path_str = "test-env"; let root = Builder::new().prefix(path_str).tempdir().unwrap(); let key: [u8; 32] = [0; 32]; fs::create_dir_all(root.path()).unwrap(); println!("{}", root.path().to_str().unwrap()); let store = LmdbRepoStore::open(root.path(), key); store.remove_expired().unwrap(); } #[test] pub fn test_store_block() { let path_str = "test-env"; let root = Builder::new().prefix(path_str).tempdir().unwrap(); let key: [u8; 32] = [0; 32]; fs::create_dir_all(root.path()).unwrap(); println!("{}", root.path().to_str().unwrap()); let mut store = LmdbRepoStore::open(root.path(), key); let block = Block::new( Vec::new(), ObjectDeps::ObjectIdList(Vec::new()), None, b"abc".to_vec(), None, ); let block_id = store.put(&block).unwrap(); assert_eq!(block_id, block.id()); println!("ObjectId: {:?}", block_id); assert_eq!( block_id, Digest::Blake3Digest32([ 155, 83, 186, 17, 95, 10, 80, 31, 111, 24, 250, 64, 8, 145, 71, 193, 103, 246, 202, 28, 202, 144, 63, 65, 85, 229, 136, 85, 202, 34, 13, 85 ]) ); let block_res = store.get(&block_id).unwrap(); println!("Block: {:?}", block_res); assert_eq!(block_res.id(), block.id()); } #[test] pub fn test_lmdb() { let path_str = "test-env"; let root = Builder::new().prefix(path_str).tempdir().unwrap(); // we set an encryption key with all zeros... for test purpose only ;) let key: [u8; 32] = [0; 32]; { fs::create_dir_all(root.path()).unwrap(); println!("{}", root.path().to_str().unwrap()); let mut manager = Manager::::singleton().write().unwrap(); let shared_rkv = manager .get_or_create(root.path(), |path| { // Rkv::new::(path) // use this instead to disable encryption Rkv::with_encryption_key_and_mapsize::(path, key, 2 * 1024 * 1024 * 1024) }) .unwrap(); let env = shared_rkv.read().unwrap(); println!("LMDB Version: {}", env.version()); let store = env.open_single("testdb", StoreOptions::create()).unwrap(); { // Use a write transaction to mutate the store via a `Writer`. There can be only // one writer for a given environment, so opening a second one will block until // the first completes. let mut writer = env.write().unwrap(); // Keys are `AsRef<[u8]>`, while values are `Value` enum instances. Use the `Blob` // variant to store arbitrary collections of bytes. Putting data returns a // `Result<(), StoreError>`, where StoreError is an enum identifying the reason // for a failure. // store.put(&mut writer, "int", &Value::I64(1234)).unwrap(); // store // .put(&mut writer, "uint", &Value::U64(1234_u64)) // .unwrap(); // store // .put(&mut writer, "float", &Value::F64(1234.0.into())) // .unwrap(); // store // .put(&mut writer, "instant", &Value::Instant(1528318073700)) // .unwrap(); // store // .put(&mut writer, "boolean", &Value::Bool(true)) // .unwrap(); // store // .put(&mut writer, "string", &Value::Str("Héllo, wörld!")) // .unwrap(); // store // .put( // &mut writer, // "json", // &Value::Json(r#"{"foo":"bar", "number": 1}"#), // ) // .unwrap(); const EXTRA: usize = 2095; // + 4096 * 524280 + 0; let key: [u8; 33] = [0; 33]; let key2: [u8; 33] = [2; 33]; let key3: [u8; 33] = [3; 33]; let key4: [u8; 33] = [4; 33]; //let value: [u8; 1977 + EXTRA] = [1; 1977 + EXTRA]; let value = vec![1; 1977 + EXTRA]; let value2: [u8; 1977 + 1] = [1; 1977 + 1]; let value4: [u8; 953 + 0] = [1; 953 + 0]; store.put(&mut writer, key, &Value::Blob(&value2)).unwrap(); store.put(&mut writer, key2, &Value::Blob(&value2)).unwrap(); // store.put(&mut writer, key3, &Value::Blob(&value)).unwrap(); // store.put(&mut writer, key4, &Value::Blob(&value4)).unwrap(); // You must commit a write transaction before the writer goes out of scope, or the // transaction will abort and the data won't persist. writer.commit().unwrap(); let reader = env.read().expect("reader"); let stat = store.stat(&reader).unwrap(); println!("LMDB stat page_size : {}", stat.page_size()); println!("LMDB stat depth : {}", stat.depth()); println!("LMDB stat branch_pages : {}", stat.branch_pages()); println!("LMDB stat leaf_pages : {}", stat.leaf_pages()); println!("LMDB stat overflow_pages : {}", stat.overflow_pages()); println!("LMDB stat entries : {}", stat.entries()); } // { // // Use a read transaction to query the store via a `Reader`. There can be multiple // // concurrent readers for a store, and readers never block on a writer nor other // // readers. // let reader = env.read().expect("reader"); // // Keys are `AsRef`, and the return value is `Result, StoreError>`. // // println!("Get int {:?}", store.get(&reader, "int").unwrap()); // // println!("Get uint {:?}", store.get(&reader, "uint").unwrap()); // // println!("Get float {:?}", store.get(&reader, "float").unwrap()); // // println!("Get instant {:?}", store.get(&reader, "instant").unwrap()); // // println!("Get boolean {:?}", store.get(&reader, "boolean").unwrap()); // // println!("Get string {:?}", store.get(&reader, "string").unwrap()); // // println!("Get json {:?}", store.get(&reader, "json").unwrap()); // println!("Get blob {:?}", store.get(&reader, "blob").unwrap()); // // Retrieving a non-existent value returns `Ok(None)`. // println!( // "Get non-existent value {:?}", // store.get(&reader, "non-existent").unwrap() // ); // // A read transaction will automatically close once the reader goes out of scope, // // so isn't necessary to close it explicitly, although you can do so by calling // // `Reader.abort()`. // } // { // // Aborting a write transaction rolls back the change(s). // let mut writer = env.write().unwrap(); // store.put(&mut writer, "foo", &Value::Blob(b"bar")).unwrap(); // writer.abort(); // let reader = env.read().expect("reader"); // println!( // "It should be None! ({:?})", // store.get(&reader, "foo").unwrap() // ); // } // { // // Explicitly aborting a transaction is not required unless an early abort is // // desired, since both read and write transactions will implicitly be aborted once // // they go out of scope. // { // let mut writer = env.write().unwrap(); // store.put(&mut writer, "foo", &Value::Blob(b"bar")).unwrap(); // } // let reader = env.read().expect("reader"); // println!( // "It should be None! ({:?})", // store.get(&reader, "foo").unwrap() // ); // } // { // // Deleting a key/value pair also requires a write transaction. // let mut writer = env.write().unwrap(); // store.put(&mut writer, "foo", &Value::Blob(b"bar")).unwrap(); // store.put(&mut writer, "bar", &Value::Blob(b"baz")).unwrap(); // store.delete(&mut writer, "foo").unwrap(); // // A write transaction also supports reading, and the version of the store that it // // reads includes the changes it has made regardless of the commit state of that // // transaction. // // In the code above, "foo" and "bar" were put into the store, then "foo" was // // deleted so only "bar" will return a result when the database is queried via the // // writer. // println!( // "It should be None! ({:?})", // store.get(&writer, "foo").unwrap() // ); // println!("Get bar ({:?})", store.get(&writer, "bar").unwrap()); // // But a reader won't see that change until the write transaction is committed. // { // let reader = env.read().expect("reader"); // println!("Get foo {:?}", store.get(&reader, "foo").unwrap()); // println!("Get bar {:?}", store.get(&reader, "bar").unwrap()); // } // writer.commit().unwrap(); // { // let reader = env.read().expect("reader"); // println!( // "It should be None! ({:?})", // store.get(&reader, "foo").unwrap() // ); // println!("Get bar {:?}", store.get(&reader, "bar").unwrap()); // } // // Committing a transaction consumes the writer, preventing you from reusing it by // // failing at compile time with an error. This line would report "error[E0382]: // // borrow of moved value: `writer`". // // store.put(&mut writer, "baz", &Value::Str("buz")).unwrap(); // } // { // // Clearing all the entries in the store with a write transaction. // { // let mut writer = env.write().unwrap(); // store.put(&mut writer, "foo", &Value::Blob(b"bar")).unwrap(); // store.put(&mut writer, "bar", &Value::Blob(b"baz")).unwrap(); // writer.commit().unwrap(); // } // // { // // let mut writer = env.write().unwrap(); // // store.clear(&mut writer).unwrap(); // // writer.commit().unwrap(); // // } // // { // // let reader = env.read().expect("reader"); // // println!( // // "It should be None! ({:?})", // // store.get(&reader, "foo").unwrap() // // ); // // println!( // // "It should be None! ({:?})", // // store.get(&reader, "bar").unwrap() // // ); // // } // } let stat = env.stat().unwrap(); let info = env.info().unwrap(); println!("LMDB info map_size : {}", info.map_size()); println!("LMDB info last_pgno : {}", info.last_pgno()); println!("LMDB info last_txnid : {}", info.last_txnid()); println!("LMDB info max_readers : {}", info.max_readers()); println!("LMDB info num_readers : {}", info.num_readers()); println!("LMDB stat page_size : {}", stat.page_size()); println!("LMDB stat depth : {}", stat.depth()); println!("LMDB stat branch_pages : {}", stat.branch_pages()); println!("LMDB stat leaf_pages : {}", stat.leaf_pages()); println!("LMDB stat overflow_pages : {}", stat.overflow_pages()); println!("LMDB stat entries : {}", stat.entries()); } // We reopen the env and data to see if it was well saved to disk. { let mut manager = Manager::::singleton().write().unwrap(); let shared_rkv = manager .get_or_create(root.path(), |path| { //Rkv::new::(path) // use this instead to disable encryption Rkv::with_encryption_key_and_mapsize::(path, key, 2 * 1024 * 1024 * 1024) }) .unwrap(); let env = shared_rkv.read().unwrap(); println!("LMDB Version: {}", env.version()); let mut store = env.open_single("testdb", StoreOptions::default()).unwrap(); //StoreOptions::create() { let reader = env.read().expect("reader"); println!( "It should be baz! ({:?})", store.get(&reader, "bar").unwrap() ); } } // Here the database and environment is closed, but the files are still present in the temp directory. // uncomment this if you need time to copy them somewhere for analysis, before the temp folder get destroyed //thread::sleep(Duration::from_millis(20000)); } }