v0.1

src/utils.rs

@@ -1,7 +1,67 @@
+use serde::{Deserialize, Serialize};
+use std::collections::HashMap;
 use std::{fs, io};
 use zstd::{Decoder, Encoder};
 
-pub async fn compress_parts(input: Vec<Vec<u8>>, output: fs::File, level: i32) {
+pub struct Zdiff {
+    pub content: HashMap<String, Vec<u8>>,
+    pub metadata: Metadata,
+}
+
+impl Zdiff {
+    pub async fn from_vec(_data: Vec<Vec<u8>>) -> Result<Self, std::io::Error> {
+        let mut content = HashMap::new();
+        for part in _data {
+            let filename_size = u32::from_be_bytes(part[0..4].try_into().unwrap()) as usize;
+            let filename = String::from_utf8(part[4..filename_size + 4].to_vec()).unwrap();
+            let cont = part[filename_size + 8..].to_vec();
+            content.insert(filename, cont);
+        }
+        let meta = content.get("metadata.json").unwrap();
+        let metadata: Metadata = serde_json::from_slice(meta.as_slice())?;
+        content.remove("metadata.json");
+
+        Ok(Zdiff { content, metadata })
+    }
+
+    pub async fn to_vec(&self) -> Vec<Vec<u8>> {
+        let mut parts: Vec<Vec<u8>> = Vec::new();
+        for (filename, content) in &self.content {
+            let filename_size: [u8; 4] = (filename.len() as u32).to_be_bytes();
+            let filename_encoded = vec![filename_size.as_slice(), filename.as_bytes()].concat();
+
+            let content_size: [u8; 4] = (content.len() as u32).to_be_bytes();
+            let content_encoded = vec![content_size.as_slice(), content.as_slice()].concat();
+            parts.push(vec![filename_encoded, content_encoded].concat())
+        }
+
+        let meta = serde_json::to_vec(&self.metadata).unwrap();
+        let meta_filename = "metadata.json";
+        let meta_filename_size = (meta_filename.len() as u32).to_be_bytes();
+        let meta_filename_encoded =
+            vec![meta_filename_size.as_slice(), meta_filename.as_bytes()].concat();
+
+        let meta_size = (meta.len() as u32).to_be_bytes();
+        let meta_encoded = vec![meta_size.as_slice(), meta.as_slice()].concat();
+        parts.push(vec![meta_filename_encoded, meta_encoded].concat());
+
+        parts
+    }
+}
+
+#[derive(Serialize, Deserialize)]
+pub struct Metadata {
+    pub(crate) diff_files: Vec<String>,
+    pub hashes: HashMap<String, String>,
+    pub remove_files: Vec<String>,
+}
+
+pub async fn get_hash(data: &Vec<u8>) -> String {
+    let hash = md5::compute(&data[..]);
+    format!("{:x}", hash)
+}
+
+pub async fn compress_parts(input: Vec<Vec<u8>>, output: &fs::File, level: i32) {
     let mut encoder = Encoder::new(output, level).unwrap();
     for part in input.iter() {
         io::copy(&mut &part[..], &mut encoder).unwrap();