Added io errors to add_entry.

src/morethantext/mod.rs

@@ -66,19 +66,24 @@ impl MoreThanText {
         })
     }
 
-    async fn add_entry(&self, entry: CacheEntry) -> String {
+    async fn add_entry(&self, entry: CacheEntry) -> Result<String, DBError> {
         let mut id: String = "".to_string();
         let mut dup = true;
         while dup {
             id = thread_rng().sample_iter(&Alphanumeric).take(32).collect();
             dup = Path::new(&self.dir).join(&id).as_path().exists().await;
         }
-        write(Path::new(&self.dir).join(&id), entry.to_bytes())
-            .await
-            .unwrap();
+        match write(Path::new(&self.dir).join(&id), entry.to_bytes()).await {
+            Ok(_) => (),
+            Err(err) => {
+                let mut error = DBError::new("data write");
+                error.add_source(err);
+                return Err(error);
+            }
+        };
         let mut cache = self.cache.lock().await;
         cache.insert(id.clone(), entry);
-        return id;
+        Ok(id)
     }
 
     async fn get_entry(&self, id: &str) -> Result<CacheEntry, DBError> {
@@ -103,6 +108,7 @@ impl MoreThanText {
 #[cfg(test)]
 mod setup {
     use super::*;
+    use async_std::fs::remove_dir_all;
     use tempfile::{tempdir, TempDir};
 
     pub struct MTT {
@@ -118,6 +124,10 @@ mod setup {
                 .unwrap();
             Self { db: db, dir: dir }
         }
+
+        pub async fn create_io_error(&self) {
+            remove_dir_all(self.dir.path().join(DATA)).await.unwrap();
+        }
     }
 }
 
@@ -151,11 +161,14 @@ mod init {
 
     #[async_std::test]
     async fn bad_data_dir() {
+        let msg = "could not create directory";
         match MoreThanText::new("kljsdgfhslkfrh").await {
             Ok(_) => assert!(false, "This test should fail to create a data directory"),
             Err(err) => {
                 assert_eq!(err.to_string(), "failed to create data directory");
                 assert!(err.source().is_some(), "Must include the source error.");
+                let err_msg = err.source().unwrap().to_string();
+                assert!(err_msg.contains(msg), "'{}' not in '{}'", msg, err_msg);
             }
         };
     }
@@ -165,14 +178,15 @@ mod init {
 mod cache {
     use super::*;
     use setup::MTT;
+    use std::error::Error;
 
     #[async_std::test]
     async fn entry_ids_are_random() {
         let mtt = MTT::new().await;
         let data1 = CacheEntry::Raw("one".to_string());
         let data2 = CacheEntry::Raw("two".to_string());
-        let id1 = mtt.db.add_entry(data1).await;
-        let id2 = mtt.db.add_entry(data2).await;
+        let id1 = mtt.db.add_entry(data1).await.unwrap();
+        let id2 = mtt.db.add_entry(data2).await.unwrap();
         assert_ne!(id1, id2, "Ids should be unique.")
     }
 
@@ -181,7 +195,7 @@ mod cache {
         let mtt = MTT::new().await;
         let data = "something";
         let expected = CacheEntry::Raw(data.to_string());
-        let id = mtt.db.add_entry(expected.clone()).await;
+        let id = mtt.db.add_entry(expected.clone()).await.unwrap();
         let output = mtt.db.get_entry(&id).await.unwrap();
         assert_eq!(output.to_string(), data);
         let dfile = mtt.dir.path().join(DATA).join(&id);
@@ -190,6 +204,22 @@ mod cache {
         assert_eq!(content, expected.to_bytes());
     }
 
+    #[async_std::test]
+    async fn store_bad_file() {
+        let mtt = MTT::new().await;
+        let msg = "could not write to file";
+        mtt.create_io_error().await;
+        match mtt.db.add_entry(CacheEntry::Raw("fail".to_string())).await {
+            Ok(_) => assert!(false, "This test should fail."),
+            Err(err) => {
+                assert_eq!(err.to_string(), "data write");
+                assert!(err.source().is_some(), "Must include the source error.");
+                let err_msg = err.source().unwrap().to_string();
+                assert!(err_msg.contains(msg), "'{}' not in '{}'", msg, err_msg);
+            }
+        }
+    }
+
     #[async_std::test]
     async fn retrieve_bad_id() {
         let mtt = MTT::new().await;
@@ -202,7 +232,11 @@ mod cache {
     #[async_std::test]
     async fn update_cache_entry() {
         let mtt = MTT::new().await;
-        let id = mtt.db.add_entry(CacheEntry::Raw("same".to_string())).await;
+        let id = mtt
+            .db
+            .add_entry(CacheEntry::Raw("same".to_string()))
+            .await
+            .unwrap();
         let expected = "different";
         mtt.db
             .update_entry(&id, CacheEntry::Raw(expected.to_string()))