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Diffstat (limited to 'lib/entry/libimagentryref/src/refstore.rs')
| -rw-r--r-- | lib/entry/libimagentryref/src/refstore.rs | 128 |
1 files changed, 0 insertions, 128 deletions
diff --git a/lib/entry/libimagentryref/src/refstore.rs b/lib/entry/libimagentryref/src/refstore.rs deleted file mode 100644 index c378d6fd..00000000 --- a/lib/entry/libimagentryref/src/refstore.rs +++ /dev/null @@ -1,128 +0,0 @@ -// -// imag - the personal information management suite for the commandline -// Copyright (C) 2015-2019 Matthias Beyer <mail@beyermatthias.de> and contributors -// -// This library is free software; you can redistribute it and/or -// modify it under the terms of the GNU Lesser General Public -// License as published by the Free Software Foundation; version -// 2.1 of the License. -// -// This library is distributed in the hope that it will be useful, -// but WITHOUT ANY WARRANTY; without even the implied warranty of -// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU -// Lesser General Public License for more details. -// -// You should have received a copy of the GNU Lesser General Public -// License along with this library; if not, write to the Free Software -// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA -// - -use std::path::Path; -use std::path::PathBuf; - -use libimagstore::store::FileLockEntry; -use libimagstore::store::Store; -use libimagstore::storeid::StoreId; - -use reference::Ref; - -use failure::Fallible as Result; -use failure::Error; - -/// A UniqueRefPathGenerator generates unique Pathes -/// -/// It is basically a functor which generates a StoreId from a &Path. -/// For more information have a look at the documentation of RefStore. -pub trait UniqueRefPathGenerator { - /// The collection the `StoreId` should be created for - fn collection() -> &'static str { - "ref" - } - - /// A function which should generate a unique string for a Path - fn unique_hash<A: AsRef<Path>>(path: A) -> Result<String>; - - /// Postprocess the generated `StoreId` object - fn postprocess_storeid(sid: StoreId) -> Result<StoreId> { - Ok(sid) - } -} - -/// A extensions for the `Store` to handle `Ref` objects -/// -/// The RefStore handles refs using a `UniqueRefPathGenerator`. The `UniqueRefPathGenerator`, as it -/// name suggests, generates unique `StoreId`s for a `&Path`. It is a functor `&Path -> StoreId`. -/// -/// It provides three functions which are called in the following sequence: -/// -/// * The `UniqueRefPathGenerator::collection()` function is used for get the collection a `StoreId` -/// should be in (The first element of the `StoreId` path) -/// * The `UniqueRefPathGenerator::unique_hash()` gets the `&Path` which it then should generate a -/// unique String for. How this is done does not matter. It can hash the Path itself, read the -/// file and hash that or something else. It should be reproduceable, though. -/// * These two parts are joined and put into a `StoreId` which the -/// `UniqueRefPathGenerator::postprocess_storeid()` function is then allowed to postprocess (for -/// example add more parts to the StoreId). The default implementation does nothing. -/// -/// The StoreId which is generated is then used to carry out the actual action (reading, creating -/// ...). -/// If a entry is created, header information is set (that it is a ref, the hash which was just -/// generated and the path of the referenced file) -/// -/// # Details -/// -/// The `UniqueRefPathGenerator` is passed as type parameter to enforce some semantics: -/// -/// * The used `UniqueRefPathGenerator` is defined by the implementation rather than by the runtime -/// of the program or some environment. Of course this is only a small hurdle to enforce this, but -/// a hint. -/// * The `UniqueRefPathGenerator` is a functor which does not carry state. -/// -pub trait RefStore<'a> { - - fn get_ref<RPG: UniqueRefPathGenerator, H: AsRef<str>>(&'a self, hash: H) -> Result<Option<FileLockEntry<'a>>>; - fn create_ref<RPG: UniqueRefPathGenerator, A: AsRef<Path>>(&'a self, path: A) -> Result<FileLockEntry<'a>>; - fn retrieve_ref<RPG: UniqueRefPathGenerator, A: AsRef<Path>>(&'a self, path: A) -> Result<FileLockEntry<'a>>; - -} - -impl<'a> RefStore<'a> for Store { - - fn get_ref<RPG: UniqueRefPathGenerator, H: AsRef<str>>(&'a self, hash: H) - -> Result<Option<FileLockEntry<'a>>> - { - let sid = StoreId::new(PathBuf::from(format!("{}/{}", RPG::collection(), hash.as_ref()))) - .map_err(Error::from)?; - - debug!("Getting: {:?}", sid); - self.get(sid) - .map_err(Error::from) - } - - fn create_ref<RPG: UniqueRefPathGenerator, A: AsRef<Path>>(&'a self, path: A) - -> Result<FileLockEntry<'a>> - { - let hash = RPG::unique_hash(&path)?; - let pathbuf = PathBuf::from(format!("{}/{}", RPG::collection(), hash)); - let sid = StoreId::new(pathbuf.clone())?; - - debug!("Creating: {:?}", sid); - self.create(sid) - .map_err(Error::from) - .and_then(|mut fle| { - fle.make_ref(hash, path)?; - Ok(fle) - }) - } - - fn retrieve_ref<RPG: UniqueRefPathGenerator, A: AsRef<Path>>(&'a self, path: A) - -> Result<FileLockEntry<'a>> - { - match self.get_ref::<RPG, String>(RPG::unique_hash(path.as_ref())?)? { - Some(r) => Ok(r), - None => self.create_ref::<RPG, A>(path), - } - } - -} - |