Add download function & fromurl command

1 files changed, 59 insertions, 0 deletions

diff --git a/src/utils.rs b/src/utils.rs
new file mode 100644
index 0000000..59a5a54
--- /dev/null
+++ b/src/utils.rs
@@ -0,0 +1,59 @@
+extern crate reqwest;
+
+use std::str;
+use std::io::{self, Read};
+
+use self::reqwest::Client;
+use self::reqwest::header::Connection;
+
+pub fn download(max_kib: usize, url: &str) -> Option<String> {
+    let response = Client::new()
+        .get(url)
+        .header(Connection::close())
+        .send();
+
+    match response {
+        Ok(mut response) => {
+            let mut body = String::new();
+
+            // 500 kilobyte buffer
+            let mut buf = [0; 500 * 1000];
+            let mut written = 0;
+            // Read until we reach EOF or max_kib KiB
+            loop {
+                let len = match response.read(&mut buf) {
+                    Ok(0) => break,
+                    Ok(len) => len,
+                    Err(ref e) if e.kind() == io::ErrorKind::Interrupted => continue,
+                    Err(e) => {
+                        debug!("Download from {:?} failed: {}", url, e);
+                        return None;
+                    }
+                };
+
+                let slice = match str::from_utf8(&buf[..len]) {
+                    Ok(slice) => slice,
+                    Err(e) => {
+                        debug!("Failed to read bytes from {:?} as UTF8: {}", url, e);
+                        return None;
+                    }
+                };
+
+                body.push_str(slice);
+                written += len;
+
+                // Check if the file is too large to download
+                if written > max_kib * 1024 {
+                    debug!("Stopping download - File from {:?} is larger than {} KiB", url, max_kib);
+                    return None;
+                }
+
+            }
+            Some(body)
+        }
+        Err(e) => {
+            debug!("Bad response from {:?}: ({})", url, e);
+            return None;
+        }
+    }
+}