initial commit

src/storage.rs

@@ -0,0 +1,85 @@
+use anyhow::{bail, Result};
+use std::{
+    fs::{create_dir_all, remove_file, rename, File},
+    path::{PathBuf, MAIN_SEPARATOR},
+    thread,
+    time::{Duration, SystemTime, UNIX_EPOCH},
+};
+
+const TMP_SUFFIX: &str = ".tmp";
+
+pub struct Item {
+    pub file: File,
+    pub path: PathBuf,
+    // pub id: u64,
+}
+
+impl Item {
+    // Constructors
+
+    pub fn create(directory: &str) -> Result<Self> {
+        loop {
+            // generate file id from current unix time
+            let id = SystemTime::now().duration_since(UNIX_EPOCH)?.as_secs();
+
+            // build optimized fs path:
+            // add directory separator after every digit to keep up to 10 files per directory
+            let path = PathBuf::from(format!(
+                "{}{MAIN_SEPARATOR}{}{TMP_SUFFIX}",
+                directory.trim_end_matches(MAIN_SEPARATOR),
+                id.to_string().chars().fold(String::new(), |mut acc, c| {
+                    if !acc.is_empty() {
+                        acc.push(MAIN_SEPARATOR);
+                    }
+                    acc.push(c);
+                    acc
+                })
+            ));
+
+            // recursively create directories
+            // * parent directory is expected
+            create_dir_all(path.parent().unwrap())?;
+
+            // build `Self`
+            match File::create_new(&path) {
+                // make sure slot is not taken (by another thread)
+                Ok(file) => {
+                    return Ok(Self {
+                        file,
+                        path,
+                        // id
+                    });
+                }
+                Err(_) => {
+                    println!("[warning] Could not init location: {:?}", path.to_str());
+                    // find free slot after some delay..
+                    thread::sleep(Duration::from_secs(1));
+                    continue;
+                }
+            }
+        }
+    }
+
+    // Actions
+
+    /// Take object processed, commit its changes
+    pub fn commit(self) -> Result<()> {
+        match self.path.to_str() {
+            Some(old) => match old.strip_suffix(TMP_SUFFIX) {
+                Some(new) => Ok(rename(old, new)?),
+                None => bail!("Invalid TMP suffix"), // | panic
+            },
+            None => bail!("Invalid Item path"), // | panic
+        }
+    }
+
+    /// Cleanup object relationships
+    pub fn delete(self) -> Result<()> {
+        Ok(remove_file(self.path)?)
+    }
+
+    // Getters
+
+    /* @TODO implement short links handle without slash
+    pub fn alias(&self, relative: &str) -> String {} */
+}