From 56a20dc6b1e5bd589c44a3c487ad318f0893407e Mon Sep 17 00:00:00 2001
From: Dmitry <b4tm4n@mail.ru>
Date: Mon, 12 Sep 2022 22:34:17 +0300
Subject: [PATCH] zip to zip

---
 .gitignore  |  1 +
 src/main.rs | 68 +++++++++++++++++++++++++++++++----------------------
 2 files changed, 41 insertions(+), 28 deletions(-)

diff --git a/.gitignore b/.gitignore
index 6f6826e..0c4ead2 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,3 +2,4 @@
 **/*.rs.bk
 baza*.zip
 /json/
+json.zip
diff --git a/src/main.rs b/src/main.rs
index e2549fc..390d928 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -3,13 +3,15 @@ extern crate json;
 extern crate tokio;
 
 use async_zip::read::fs::ZipFileReader;
+use async_zip::write::{EntryOptions, ZipFileWriter};
+use async_zip::Compression;
 use std::path::PathBuf;
 use std::str::FromStr;
+use tokio::io::{AsyncBufReadExt, AsyncReadExt, AsyncWrite, BufReader};
 use tokio::{fs, task};
-use tokio::io::{AsyncBufReadExt, AsyncReadExt, AsyncWriteExt, BufReader};
 
-const BASE_FILENAME: &str = "baza_utf8.zip";
-const OUTPUT_PATH: &str = "json";
+const INPUT_FILENAME: &str = "baza_utf8.zip";
+const OUTPUT_FILENAME: &str = "json.zip";
 
 #[derive(Debug, Clone, Copy)]
 enum KeywordType {
@@ -219,59 +221,69 @@ async fn parse_file(
     Ok(ctx.data.clone())
 }
 
-async fn process_file(
+async fn process_file<T: AsyncWrite + Unpin>(
     archive: &ZipFileReader,
+    writer: &mut ZipFileWriter<T>,
     index: usize,
     name: String,
 ) -> Result<(), Box<dyn std::error::Error>> {
     let entry_reader = archive.entry_reader(index).await?;
 
-    // make output filename
-    let mut outfilename = PathBuf::from(OUTPUT_PATH);
-    outfilename.push(name);
-    outfilename.set_extension("json");
-
-    // save json to file
+    // parse file to json
     let new_data = parse_file(entry_reader).await?;
-    let data_str = task::spawn_blocking(move || {
-        new_data.pretty(2)
-    }).await?;
 
-    let mut outfile = fs::File::create(outfilename).await?;
-    outfile.write_all(data_str.as_bytes()).await?;
+    // dump json to str
+    let data_str = task::spawn_blocking(move || new_data.pretty(2)).await?;
+
+    // make output filename
+    let mut outfilename = PathBuf::from(name);
+    outfilename.set_extension("json");
+    let outfilename = outfilename.to_str().unwrap().to_string();
+    let opts = EntryOptions::new(outfilename, Compression::Deflate);
+
+    // write new zip entry
+    writer.write_entry_whole(opts, data_str.as_bytes()).await?;
+
     Ok(())
 }
 
 #[tokio::main]
 async fn main() -> Result<(), Box<dyn std::error::Error>> {
     // open archive just to list files
-    let archive = ZipFileReader::new(String::from(BASE_FILENAME)).await?;
+    let archive = ZipFileReader::new(String::from(INPUT_FILENAME)).await?;
 
     let source_files: Vec<(usize, String)> = archive
         .entries()
         .iter()
         .enumerate()
-        .filter(|item| !item.1.dir())
-        .filter(|item| {
+        .filter(|(_, entry)| !entry.dir())
+        .filter(|(_, entry)| {
             // skip files without "txt" extension
-            item.1.name().ends_with(".txt")
+            entry.name().ends_with(".txt")
         })
-        .map(|item| (item.0, item.1.name().to_string()))
+        .map(|(index, entry)| (index, entry.name().to_string()))
         .collect();
 
-    // check output directory
-    match fs::metadata(OUTPUT_PATH).await {
-        Err(_) => fs::create_dir_all(OUTPUT_PATH).await?,
-        Ok(x) if x.is_file() => return Err("output directory is file!".into()),
+    // check output filename
+    match fs::metadata(OUTPUT_FILENAME).await {
+        Ok(x) if x.is_dir() => return Err("output file is a directory!".into()),
         _ => (),
     };
 
-    println!("processing {} files ...", source_files.len());
+    println!(
+        r#" 【 "{}" ➡ "{}" 】 processing {} files 💾⏳ ..."#,
+        INPUT_FILENAME,
+        OUTPUT_FILENAME,
+        source_files.len()
+    );
 
-    for i in source_files {
-        process_file(&archive, i.0, i.1).await?;
+    let mut file = fs::File::create(OUTPUT_FILENAME).await?;
+    let mut writer = ZipFileWriter::new(&mut file);
+    for (index, name) in source_files {
+        process_file(&archive, &mut writer, index, name).await?;
     }
+    writer.close().await?;
 
-    println!("done");
+    println!("done ✅");
     Ok(())
 }