Add support for Bzip compression (includes .tar.bz2 and .zip.bz2 and etc)

src/compressors/bzip.rs

@@ -0,0 +1,103 @@
+use std::{fs, io::{self, Read, Write}, path::PathBuf};
+
+use colored::Colorize;
+
+use crate::{error::{Error, OuchResult}, extension::CompressionFormat, file::File};
+use crate::utils::ensure_exists;
+
+use super::{Compressor, Entry};
+
+pub struct BzipCompressor {}
+
+struct CompressorToMemory {}
+
+// impl CompressorToMemory {
+//     pub fn compress_files(files: Vec<PathBuf>, format: CompressionFormat) -> OuchResult<Vec<u8>> {
+//         let mut buffer = vec![];
+
+//         if files.len() != 1 {
+//             eprintln!("{}: cannot compress multiple files directly to {:#?}.\n     Try using an intermediate archival method such as Tar.\n     Example: filename.tar{}", "error".red(), format, format);
+//             return Err(Error::InvalidInput);
+//         }
+
+//         let mut contents = Vec::new();
+//         let path = &files[0];
+//         ensure_exists(path)?;
+
+//         let bytes_read = {
+//             let bytes = fs::read(path)?;
+//             let mut encoder = get_encoder(&format, Box::new(&mut buffer));
+//             encoder.write_all(&*bytes)?;
+//             bytes.as_slice().read_to_end(&mut contents)?
+//         };
+
+//         println!("{}: compressed {:?} into memory ({} bytes)", "info".yellow(), &path, bytes_read);
+        
+//         Ok(contents)
+//     }
+
+//     pub fn compress_bytes(file: File) {
+        
+//     }
+// }
+
+impl BzipCompressor {
+    fn compress_files(files: Vec<PathBuf>, format: CompressionFormat) -> OuchResult<Vec<u8>> {
+        if files.len() != 1 {
+            eprintln!("{}: cannot compress multiple files directly to {:#?}.\n     Try using an intermediate archival method such as Tar.\n     Example: filename.tar{}", "error".red(), format, format);
+            return Err(Error::InvalidInput);
+        }
+        let path = &files[0];
+        ensure_exists(path)?;
+        let contents = {
+            let bytes = fs::read(path)?;
+            Self::compress_bytes(&*bytes)?
+        };
+
+        println!("{}: compressed {:?} into memory ({} bytes)", "info".yellow(), &path, contents.len());
+        
+        Ok(contents)
+    }
+
+    fn compress_file_in_memory(file: File) -> OuchResult<Vec<u8>> {
+        // Ensure that our file has in-memory content
+        let bytes = match file.contents_in_memory {
+            Some(bytes) => bytes,
+            None => {
+                // TODO: error message,
+                return Err(Error::InvalidInput);
+            }
+        };
+
+        Ok(Self::compress_bytes(&*bytes)?)
+    }
+
+    fn compress_bytes(bytes: &[u8]) -> OuchResult<Vec<u8>> {
+        let buffer = vec![];
+        let mut encoder = bzip2::write::BzEncoder::new(buffer, bzip2::Compression::new(6));
+        encoder.write_all(bytes)?;
+        Ok(encoder.finish()?)
+    }
+
+}
+
+// TODO: customizable compression level
+fn get_encoder<'a>(format: &CompressionFormat, buffer: Box<dyn io::Write + Send + 'a>) -> Box<dyn io::Write + Send + 'a> {
+    match format {
+        CompressionFormat::Bzip => Box::new(bzip2::write::BzEncoder::new(buffer, bzip2::Compression::new(4))),
+        _other => unreachable!()
+    }
+}
+
+impl Compressor for BzipCompressor {
+    fn compress(&self, from: Entry) -> OuchResult<Vec<u8>> {
+        match from {
+            Entry::Files(files) => Ok(
+                Self::compress_files(files, CompressionFormat::Bzip)?
+            ),
+            Entry::InMemory(file) => Ok(
+                Self::compress_file_in_memory(file)?
+            ),
+        }
+    }
+}

src/compressors/mod.rs

@@ -1,10 +1,10 @@
 mod tar;
 mod zip;
-mod unified;
+mod bzip;
 mod compressor;
 
 pub use compressor::Compressor;
 pub use self::compressor::Entry;
 pub use self::tar::TarCompressor;
 pub use self::zip::ZipCompressor;
-
+pub use self::bzip::BzipCompressor;

src/decompressors/tomemory.rs

@@ -16,7 +16,7 @@ use crate::{
 use super::decompressor::DecompressionResult;
 use super::decompressor::Decompressor;
 
-pub struct UnifiedDecompressor {}
+struct DecompressorToMemory {}
 pub struct GzipDecompressor {}
 pub struct LzmaDecompressor {}
 pub struct BzipDecompressor {}
@@ -30,7 +30,7 @@ fn get_decoder<'a>(format: CompressionFormat, buffer: Box<dyn io::Read + Send +
     }
 }
 
-impl UnifiedDecompressor {
+impl DecompressorToMemory {
     fn unpack_file(from: &Path, format: CompressionFormat) -> OuchResult<Vec<u8>> {
         let file = std::fs::read(from)?;
 
@@ -62,18 +62,18 @@ impl UnifiedDecompressor {
 
 impl Decompressor for GzipDecompressor {
     fn decompress(&self, from: File, into: &Option<File>) -> OuchResult<DecompressionResult> {
-        UnifiedDecompressor::decompress(from, CompressionFormat::Gzip, into)
+        DecompressorToMemory::decompress(from, CompressionFormat::Gzip, into)
     }
 }
 
 impl Decompressor for BzipDecompressor {
     fn decompress(&self, from: File, into: &Option<File>) -> OuchResult<DecompressionResult> {
-        UnifiedDecompressor::decompress(from, CompressionFormat::Bzip, into)
+        DecompressorToMemory::decompress(from, CompressionFormat::Bzip, into)
     }
 }
 
 impl Decompressor for LzmaDecompressor {
     fn decompress(&self, from: File, into: &Option<File>) -> OuchResult<DecompressionResult> {
-        UnifiedDecompressor::decompress(from, CompressionFormat::Lzma, into)
+        DecompressorToMemory::decompress(from, CompressionFormat::Lzma, into)
     }
 }

src/evaluator.rs

@@ -6,7 +6,8 @@ use crate::compressors::{
     Entry,
     Compressor,
     TarCompressor,
-    ZipCompressor
+    ZipCompressor,
+    BzipCompressor,
 };
 
 use crate::decompressors::{
@@ -69,6 +70,7 @@ impl Evaluator {
         let second_compressor: Box<dyn Compressor> = match extension.second_ext {
             CompressionFormat::Tar  => Box::new(TarCompressor {}),
             CompressionFormat::Zip  => Box::new(ZipCompressor {}),
+            CompressionFormat::Bzip => Box::new(BzipCompressor {}),
             _other => todo!()
         };
 

src/extension.rs

@@ -1,4 +1,9 @@
-use std::{convert::TryFrom, ffi::OsStr, path::{Path, PathBuf}};
+use std::{
+    convert::TryFrom,
+    ffi::OsStr,
+    fmt::Display,
+    path::{Path, PathBuf},
+};
 
 use crate::error;
 use CompressionFormat::*;
@@ -9,15 +14,13 @@ use CompressionFormat::*;
 #[derive(Clone, Debug, PartialEq, Eq)]
 pub struct Extension {
     pub first_ext: Option<CompressionFormat>,
-    pub second_ext: CompressionFormat
+    pub second_ext: CompressionFormat,
 }
 
 pub fn get_extension_from_filename(filename: &str) -> Option<(&str, &str)> {
     let path = Path::new(filename);
 
-    let ext = path
+    let ext = path.extension().and_then(OsStr::to_str)?;
-        .extension()
-        .and_then(OsStr::to_str)?;
 
     let previous_extension = path
         .file_stem()
@@ -35,34 +38,28 @@ impl From<CompressionFormat> for Extension {
     fn from(second_ext: CompressionFormat) -> Self {
         Self {
             first_ext: None,
-            second_ext
+            second_ext,
         }
     }
 }
 
 impl Extension {
     pub fn new(filename: &str) -> error::OuchResult<Self> {
-        let ext_from_str = |ext| {
+        let ext_from_str = |ext| match ext {
-            match ext {
             "zip" => Ok(Zip),
             "tar" => Ok(Tar),
             "gz" => Ok(Gzip),
             "bz" | "bz2" => Ok(Bzip),
             "lz" | "lzma" => Ok(Lzma),
             other => Err(error::Error::UnknownExtensionError(other.into())),
-            }
         };
 
         let (first_ext, second_ext) = match get_extension_from_filename(filename) {
-            Some(extension_tuple) => {
+            Some(extension_tuple) => match extension_tuple {
-                match extension_tuple {
                 ("", snd) => (None, snd),
-                    (fst, snd)=> (Some(fst), snd)
+                (fst, snd) => (Some(fst), snd),
-                }
             },
-            None => {
+            None => return Err(error::Error::MissingExtensionError(filename.into())),
-                return Err(error::Error::MissingExtensionError(filename.into()))
-            }
         };
 
         let (first_ext, second_ext) = match (first_ext, second_ext) {
@@ -77,12 +74,10 @@ impl Extension {
             }
         };
 
-        Ok(
+        Ok(Self {
-            Self {
             first_ext,
-                second_ext
+            second_ext,
-            }
+        })
-        )
     }
 }
 
@@ -123,7 +118,6 @@ impl TryFrom<&PathBuf> for CompressionFormat {
     type Error = error::Error;
 
     fn try_from(ext: &PathBuf) -> Result<Self, Self::Error> {
-
         let ext = match ext.extension() {
             Some(ext) => ext,
             None => {
@@ -147,3 +141,19 @@ impl TryFrom<&str> for CompressionFormat {
         extension_from_os_str(ext)
     }
 }
+
+impl Display for CompressionFormat {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        write!(
+            f,
+            "{}",
+            match self {
+                Gzip => ".gz",
+                Bzip => ".bz",
+                Lzma => ".lz",
+                Tar => ".tar",
+                Zip => ".zip",
+            }
+        )
+    }
+}

src/utils.rs

@@ -3,6 +3,16 @@ use std::{fs, path::Path};
 use colored::Colorize;
 use crate::{error::OuchResult, file::File};
 
+pub (crate) fn ensure_exists<'a, P>(path: P) -> OuchResult<()>
+where
+    P: AsRef<Path> + 'a   {
+        let exists = path.as_ref().exists();
+        if !exists {
+            eprintln!("{}: could not find file {:?}", "error".red(), path.as_ref());
+        }
+        Ok(())
+    }
+
 pub (crate) fn create_path_if_non_existent(path: &Path) -> OuchResult<()> {
     if !path.exists() {
         println!(