1 files changed, 150 insertions, 0 deletions
diff --git a/cli/disk_cache.rs b/cli/disk_cache.rs
new file mode 100644
index 000000000..808cfe675
--- /dev/null
+++ b/cli/disk_cache.rs
@@ -0,0 +1,150 @@
+use crate::fs as deno_fs;
+use std::ffi::OsStr;
+use std::fs;
+use std::path::Path;
+use std::path::PathBuf;
+use url::Url;
+
+#[derive(Clone)]
+pub struct DiskCache {
+  pub location: PathBuf,
+}
+
+impl DiskCache {
+  pub fn new(location: &Path) -> Self {
+    // TODO: ensure that 'location' is a directory
+    Self {
+      location: location.to_owned(),
+    }
+  }
+
+  pub fn get_cache_filename(self: &Self, url: &Url) -> PathBuf {
+    let mut out = PathBuf::new();
+
+    let scheme = url.scheme();
+    out.push(scheme);
+    match scheme {
+      "http" | "https" => {
+        let host = url.host_str().unwrap();
+        let host_port = match url.port() {
+          // Windows doesn't support ":" in filenames, so we represent port using a
+          // special string.
+          Some(port) => format!("{}_PORT{}", host, port),
+          None => host.to_string(),
+        };
+        out.push(host_port);
+      }
+      _ => {}
+    };
+
+    for path_seg in url.path_segments().unwrap() {
+      out.push(path_seg);
+    }
+    out
+  }
+
+  pub fn get_cache_filename_with_extension(
+    self: &Self,
+    url: &Url,
+    extension: &str,
+  ) -> PathBuf {
+    let base = self.get_cache_filename(url);
+
+    match base.extension() {
+      None => base.with_extension(extension),
+      Some(ext) => {
+        let original_extension = OsStr::to_str(ext).unwrap();
+        let final_extension = format!("{}.{}", original_extension, extension);
+        base.with_extension(final_extension)
+      }
+    }
+  }
+
+  pub fn get(self: &Self, filename: &Path) -> std::io::Result<Vec<u8>> {
+    let path = self.location.join(filename);
+    fs::read(&path)
+  }
+
+  pub fn set(self: &Self, filename: &Path, data: &[u8]) -> std::io::Result<()> {
+    let path = self.location.join(filename);
+    match path.parent() {
+      Some(ref parent) => fs::create_dir_all(parent),
+      None => Ok(()),
+    }?;
+    deno_fs::write_file(&path, data, 0o666)
+  }
+
+  pub fn remove(self: &Self, filename: &Path) -> std::io::Result<()> {
+    let path = self.location.join(filename);
+    fs::remove_file(path)
+  }
+}
+
+#[cfg(test)]
+mod tests {
+  use super::*;
+
+  #[test]
+  fn test_get_cache_filename() {
+    let cache = DiskCache::new(&PathBuf::from("foo"));
+
+    let test_cases = [
+      (
+        "http://deno.land/std/http/file_server.ts",
+        "http/deno.land/std/http/file_server.ts",
+      ),
+      (
+        "http://localhost:8000/std/http/file_server.ts",
+        "http/localhost_PORT8000/std/http/file_server.ts",
+      ),
+      (
+        "https://deno.land/std/http/file_server.ts",
+        "https/deno.land/std/http/file_server.ts",
+      ),
+      (
+        "file:///std/http/file_server.ts",
+        "file/std/http/file_server.ts",
+      ),
+    ];
+
+    for test_case in &test_cases {
+      assert_eq!(
+        cache.get_cache_filename(&Url::parse(test_case.0).unwrap()),
+        PathBuf::from(test_case.1)
+      )
+    }
+  }
+
+  #[test]
+  fn test_get_cache_filename_with_extension() {
+    let cache = DiskCache::new(&PathBuf::from("foo"));
+
+    let test_cases = [
+      (
+        "http://deno.land/std/http/file_server.ts",
+        "js",
+        "http/deno.land/std/http/file_server.ts.js",
+      ),
+      (
+        "file:///std/http/file_server",
+        "js",
+        "file/std/http/file_server.js",
+      ),
+      (
+        "http://deno.land/std/http/file_server.ts",
+        "js.map",
+        "http/deno.land/std/http/file_server.ts.js.map",
+      ),
+    ];
+
+    for test_case in &test_cases {
+      assert_eq!(
+        cache.get_cache_filename_with_extension(
+          &Url::parse(test_case.0).unwrap(),
+          test_case.1
+        ),
+        PathBuf::from(test_case.2)
+      )
+    }
+  }
+}