feat: Expose set_wal_compression_type (#817)

src/db_options.rs

@@ -1065,6 +1065,31 @@ impl Options {
         }
     }
 
+    /// Sets the compression algorithm that will be used for compressing WAL.
+    ///
+    /// At present, only ZSTD compression is supported!
+    ///
+    /// Default: `DBCompressionType::None`
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use rocksdb::{Options, DBCompressionType};
+    ///
+    /// let mut opts = Options::default();
+    /// opts.set_wal_compression_type(DBCompressionType::Zstd);
+    /// // Or None to disable it
+    /// opts.set_wal_compression_type(DBCompressionType::None);
+    /// ```
+    pub fn set_wal_compression_type(&mut self, t: DBCompressionType) {
+        match t {
+            DBCompressionType::None | DBCompressionType::Zstd => unsafe {
+                ffi::rocksdb_options_set_wal_compression(self.inner, t as c_int);
+            },
+            other => unimplemented!("{:?} is not supported for WAL compression", other),
+        }
+    }
+
     /// Sets the bottom-most compression algorithm that will be used for
     /// compressing blocks at the bottom-most level.
     ///

tests/test_rocksdb_options.rs

@@ -171,6 +171,28 @@ fn set_compression_options_zstd_max_train_bytes() {
     }
 }
 
+#[test]
+fn set_wal_compression_zstd() {
+    let path = DBPath::new("_set_wal_compression_zstd");
+    {
+        let mut opts = Options::default();
+        opts.create_if_missing(true);
+        opts.set_wal_compression_type(DBCompressionType::None);
+        opts.set_wal_compression_type(DBCompressionType::Zstd);
+        let _db = DB::open(&opts, &path).unwrap();
+    }
+}
+
+#[test]
+#[should_panic(expected = "Lz4 is not supported for WAL compression")]
+fn set_wal_compression_unsupported() {
+    {
+        let mut opts = Options::default();
+        opts.create_if_missing(true);
+        opts.set_wal_compression_type(DBCompressionType::Lz4);
+    }
+}
+
 fn test_compression_type(ty: DBCompressionType) {
     let path = DBPath::new("_test_compression_type");