start implementing DataStore

src/backup/datastore.rs

@@ -0,0 +1,43 @@
+use failure::*;
+
+use std::path::Path;
+
+use crate::config::datastore;
+use super::chunk_store::*;
+use super::image_index::*;
+
+pub struct DataStore {
+    chunk_store: ChunkStore,
+}
+
+impl DataStore {
+
+    pub fn open(store_name: &str) -> Result<Self, Error> {
+
+        let config = datastore::config()?;
+        let (_, store_config) = config.sections.get(store_name)
+            .ok_or(format_err!("no such datastore '{}'", store_name))?;
+
+        let path = store_config["path"].as_str().unwrap();
+
+        let chunk_store = ChunkStore::open(path)?;
+
+        Ok(Self {
+            chunk_store: chunk_store,
+        })
+    }
+
+    pub fn create_image_writer<P: AsRef<Path>>(&mut self, filename: P, size: usize) -> Result<ImageIndexWriter, Error> {
+
+        let index = ImageIndexWriter::create(&mut self.chunk_store, filename.as_ref(), size)?;
+
+        Ok(index)
+    }
+
+    pub fn open_image_reader<P: AsRef<Path>>(&mut self, filename: P) -> Result<ImageIndexReader, Error> {
+
+        let index = ImageIndexReader::open(&mut self.chunk_store, filename.as_ref())?;
+
+        Ok(index)
+    }
+}