Merge pull request #95 from blandger/fix_parametrized_remote_url_down…

…load

Correct downloading remote resource with parametrized url

Cargo.toml

@@ -42,6 +42,7 @@ html_parser = "0.7.0"
 url = "2.3"
 ureq = "2.9"
 const_format = "0.2.31"
+uuid = "1.8"
 
 [dev-dependencies]
 tempfile = "3"

src/resources/retrieve.rs

@@ -22,7 +22,7 @@ pub(crate) trait ContentRetriever {
                     fs::create_dir_all(cache_dir)?;
                 }
                 debug!("Downloading asset : {}", url);
-                let mut file = OpenOptions::new().create(true).write(true).open(dest)?;
+                let mut file = OpenOptions::new().create(true).truncate(true).write(true).open(dest)?;
                 let mut resp = self.retrieve(url.as_str())?;
                 io::copy(&mut resp, &mut file)?;
                 debug!("Downloaded asset by '{}'", url);
@@ -117,6 +117,27 @@ mod tests {
         panic!("{}", r.unwrap_err().to_string());
     }
 
+    #[test]
+    fn download_parametrized_avatar_image() {
+        use std::io::Read;
+
+        struct TestHandler;
+        impl ContentRetriever for TestHandler {
+            fn retrieve(&self, _url: &str) -> Result<BoxRead, Error> {
+                Ok(Box::new("Downloaded content".as_bytes()))
+            }
+        }
+        let cr = TestHandler {};
+        let a = temp_remote_asset("https://avatars.githubusercontent.com/u/274803?v=4").unwrap();
+        let r = cr.download(&a);
+        assert!(r.is_ok());
+
+        let mut buffer = String::new();
+        let mut f = std::fs::File::open(&a.location_on_disk).unwrap();
+        f.read_to_string(&mut buffer).unwrap();
+        assert_eq!(buffer, "Downloaded content");
+    }
+
     fn temp_remote_asset(url: &str) -> Result<Asset, Error> {
         let tmp_dir = TempDir::new().unwrap();
         let dest_dir = tmp_dir.path().join("mdbook-epub");

src/utils.rs

@@ -2,6 +2,7 @@ use pulldown_cmark::{Options, Parser};
 use std::ffi::OsStr;
 use std::path::{Component, Path, PathBuf};
 use url::Url;
+use uuid::Uuid;
 
 pub(crate) fn create_new_pull_down_parser(text: &str) -> Parser<'_, '_> {
     let mut opts = Options::empty();
@@ -40,24 +41,43 @@ pub fn normalize_path(path: &Path) -> PathBuf {
     ret
 }
 
+/// Generate file name + extension from supplied remote URL.
+/// If url does not contain file extension because of 'parametrized url'
+/// then file's extension is generated as UUID4 value and file name
+/// is hashed from URL itself.
 pub(crate) fn hash_link(url: &Url) -> String {
     use std::collections::hash_map::DefaultHasher;
     use std::hash::{Hash, Hasher};
 
     let mut hasher = DefaultHasher::new();
     url.hash(&mut hasher);
     let path = PathBuf::from(url.path());
+    let _generated_file_extension = Uuid::new_v4().to_string();
     let ext = path
         .extension()
         .and_then(OsStr::to_str)
-        .unwrap_or_else(|| panic!("Unable to extract file ext from {url}"));
+        .unwrap_or(_generated_file_extension.as_str());
     format!("{:x}.{}", hasher.finish(), ext)
 }
 
 #[cfg(test)]
 mod tests {
     use super::*;
 
+    #[test]
+    fn test_hash_named_url_with_extention() {
+        let test_url = "https://www.rust-lang.org/static/images/rust-logo-blk.svg";
+        let hashed_filename = hash_link(&test_url.parse::<Url>().unwrap());
+        assert_eq!("b20b2723e874918.svg", hashed_filename);
+    }
+
+    #[test]
+    fn test_hash_parametrized_url_no_extension() {
+        let test_avatar_url = "https://avatars.githubusercontent.com/u/274803?v=4";
+        let hashed_filename = hash_link(&test_avatar_url.parse::<Url>().unwrap());
+        assert!(hashed_filename.starts_with("4dbdb25800b6fa1b."));
+    }
+
     #[cfg(not(target_os = "windows"))]
     #[test]
     fn test_normalize_path() {

tests/dummy/src/01_getting_started/02_article.md

@@ -3,4 +3,15 @@
 We all love how Rust empowers us to write fast, safe software.
 
 **Fig 1: Before and after example**
-![swap_problem](../assets/rust-logo.png)
+![swap_problem](../assets/rust-logo.png)
+
+
+```powershell
+if (Test-Path "myproject.zip") {
+    del "myproject.zip";
+}
+& "c:\Program Files\7-Zip\7z.exe" a myproject.zip .\myproject\ "-xr!.git" "-xr!.gitignore"
+pause
+```
+
+![Image](https://avatars.githubusercontent.com/u/274803?v=4)

tests/integration_tests.rs

@@ -134,7 +134,7 @@ fn rendered_document_contains_all_chapter_files_and_assets() {
     let mut doc = generate_epub().unwrap();
     debug!("Number of internal epub resources = {:?}", doc.0.resources);
     // number of internal epub resources for dummy test book
-    assert_eq!(8, doc.0.resources.len());
+    assert_eq!(9, doc.0.resources.len());
     assert_eq!(2, doc.0.spine.len());
     assert_eq!(doc.0.mdata("title").unwrap(), "DummyBook");
     assert_eq!(doc.0.mdata("language").unwrap(), "en");