1 files changed, 147 insertions, 0 deletions
diff --git a/zellij-utils/src/downloader/mod.rs b/zellij-utils/src/downloader/mod.rs
new file mode 100644
index 000000000..b0b2771dd
--- /dev/null
+++ b/zellij-utils/src/downloader/mod.rs
@@ -0,0 +1,147 @@
+pub mod download;
+
+use async_std::{
+    fs::{create_dir_all, File},
+    io::{ReadExt, WriteExt},
+    stream, task,
+};
+use futures::{StreamExt, TryStreamExt};
+use std::path::PathBuf;
+use surf::Client;
+use thiserror::Error;
+
+use self::download::Download;
+
+#[derive(Error, Debug)]
+pub enum DownloaderError {
+    #[error("RequestError: {0}")]
+    Request(surf::Error),
+    #[error("StatusError: {0}, StatusCode: {1}")]
+    Status(String, surf::StatusCode),
+    #[error("IoError: {0}")]
+    Io(#[source] std::io::Error),
+    #[error("IoPathError: {0}, File: {1}")]
+    IoPath(std::io::Error, PathBuf),
+}
+
+#[derive(Default, Debug)]
+pub struct Downloader {
+    client: Client,
+    directory: PathBuf,
+}
+
+impl Downloader {
+    pub fn new(directory: PathBuf) -> Self {
+        Self {
+            client: surf::client().with(surf::middleware::Redirect::default()),
+            directory,
+        }
+    }
+
+    pub fn set_directory(&mut self, directory: PathBuf) {
+        self.directory = directory;
+    }
+
+    pub fn download(&self, downloads: &[Download]) -> Vec<Result<(), DownloaderError>> {
+        task::block_on(async {
+            stream::from_iter(downloads)
+                .map(|download| self.fetch(download))
+                .buffer_unordered(4)
+                .collect::<Vec<_>>()
+                .await
+        })
+    }
+
+    pub async fn fetch(&self, download: &Download) -> Result<(), DownloaderError> {
+        let mut file_size: usize = 0;
+
+        let file_path = self.directory.join(&download.file_name);
+
+        if file_path.exists() {
+            file_size = match file_path.metadata() {
+                Ok(metadata) => metadata.len() as usize,
+                Err(e) => return Err(DownloaderError::IoPath(e, file_path)),
+            }
+        }
+
+        let response = self
+            .client
+            .get(&download.url)
+            .await
+            .map_err(|e| DownloaderError::Request(e))?;
+        let status = response.status();
+
+        if status.is_client_error() || status.is_server_error() {
+            return Err(DownloaderError::Status(
+                status.canonical_reason().to_string(),
+                status,
+            ));
+        }
+
+        let length = response.len().unwrap_or(0);
+        if length > 0 && length == file_size {
+            return Ok(());
+        }
+
+        let mut dest = {
+            create_dir_all(&self.directory)
+                .await
+                .map_err(|e| DownloaderError::IoPath(e, self.directory.clone()))?;
+            File::create(&file_path)
+                .await
+                .map_err(|e| DownloaderError::IoPath(e, file_path))?
+        };
+
+        let mut bytes = response.bytes();
+        while let Some(byte) = bytes.try_next().await.map_err(DownloaderError::Io)? {
+            dest.write_all(&[byte]).await.map_err(DownloaderError::Io)?;
+        }
+
+        Ok(())
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    use tempfile::tempdir;
+
+    #[test]
+    #[ignore]
+    fn test_fetch_plugin() {
+        let dir = tempdir().expect("could not get temp dir");
+        let dir_path = dir.path();
+
+        let downloader = Downloader::new(dir_path.to_path_buf());
+        let dl = Download::from(
+            "https://github.com/imsnif/monocle/releases/download/0.37.2/monocle.wasm",
+        );
+
+        let result = task::block_on(downloader.fetch(&dl));
+
+        assert!(result.is_ok());
+    }
+
+    #[test]
+    #[ignore]
+    fn test_download_plugins() {
+        let dir = tempdir().expect("could not get temp dir");
+        let dir_path = dir.path();
+
+        let downloader = Downloader::new(dir_path.to_path_buf());
+        let downloads = vec![
+            Download::from(
+                "https://github.com/imsnif/monocle/releases/download/0.37.2/monocle.wasm",
+            ),
+            Download::from(
+                "https://github.com/imsnif/multitask/releases/download/0.38.2/multitask.wasm",
+            ),
+        ];
+
+        let results = downloader.download(&downloads);
+        for result in results {
+            assert!(result.is_ok())
+        }
+    }
+}