Merge pull request #32 from spacejam/tyler_nuke_DBResult

nuke db result

.gitignore

@@ -2,3 +2,4 @@
 *.swp
 target
 Cargo.lock
+*.orig

Cargo.toml

@@ -2,7 +2,7 @@
 
 name = "rocksdb"
 description = "A Rust wrapper for Facebook's RocksDB embeddable database."
-version = "0.1.1"
+version = "0.2.0"
 authors = ["Tyler Neely <t@jujit.su>", "David Greenberg <dsg123456789@gmail.com>"]
 license = "Apache-2.0"
 keywords = ["database", "embedded", "LSM-tree", "persistence"]

README.md

@@ -3,7 +3,7 @@ rust-rocksdb
 [![Build Status](https://travis-ci.org/spacejam/rust-rocksdb.svg?branch=master)](https://travis-ci.org/spacejam/rust-rocksdb)
 [![crates.io](http://meritbadge.herokuapp.com/rocksdb)](https://crates.io/crates/rocksdb)
 
-This library has been tested against RocksDB 3.13.1 on linux and OSX.  The 0.1.1 crate should work with the Rust 1.2 stable and nightly releases as of 9/7/15.
+This library has been tested against RocksDB 3.13.1 on linux and OSX.  The 0.2.0 crate should work with the Rust 1.4 stable and nightly releases as of 11/7/15.
 
 ### status
   - [x] basic open/put/get/delete/close
@@ -16,6 +16,7 @@ This library has been tested against RocksDB 3.13.1 on linux and OSX.  The 0.1.1
   - [x] comparator
   - [x] snapshot
   - [x] column family operations
+  - [ ] prefix seek
   - [ ] slicetransform
   - [ ] windows support
 
@@ -35,7 +36,7 @@ sudo make install
 ###### Cargo.toml
 ```rust
 [dependencies]
-rocksdb = "~0.1.1"
+rocksdb = "~0.2.0"
 ```
 ###### Code
 ```rust
@@ -45,12 +46,11 @@ use rocksdb::{DB, Writable};
 fn main() {
     let mut db = DB::open_default("/path/for/rocksdb/storage").unwrap();
     db.put(b"my key", b"my value");
-    db.get(b"my key")
-        .map( |value| {
-            println!("retrieved value {}", value.to_utf8().unwrap())
-        })
-        .on_absent( || { println!("value not found") })
-        .on_error( |e| { println!("operational problem encountered: {}", e) });
+    match db.get(b"my key") {
+        Ok(Some(value)) => println!("retrieved value {}", value.to_utf8().unwrap()),
+        Ok(None) => println!("value not found"),
+        Err(e) => println!("operational problem encountered: {}", e), 
+    }
 
     db.delete(b"my key");
 }
@@ -141,7 +141,7 @@ fn main() {
     db.merge(b"k1", b"d");
     db.merge(b"k1", b"efg");
     let r = db.get(b"k1");
-    assert!(r.unwrap().to_utf8().unwrap() == "abcdefg");
+    assert!(r.unwrap().unwrap().to_utf8().unwrap() == "abcdefg");
 }
 ```
 

src/lib.rs

@@ -15,7 +15,7 @@
 */
 pub use ffi as rocksdb_ffi;
 pub use ffi::{new_bloom_filter, DBCompactionStyle, DBComparator};
-pub use rocksdb::{DB, DBResult, DBVector, WriteBatch, Writable, Direction};
+pub use rocksdb::{DB, DBVector, WriteBatch, Writable, Direction};
 pub use rocksdb_options::{Options, BlockBasedOptions};
 pub use merge_operator::MergeOperands;
 pub mod rocksdb;

src/main.rs

@@ -48,16 +48,18 @@ fn main() {
     let path = "/tmp/rust-rocksdb";
     let db = DB::open_default(path).unwrap();
     assert!(db.put(b"my key", b"my value").is_ok());
-    db.get(b"my key").map( |value| {
+    match db.get(b"my key") {
+        Ok(Some(value)) => {
             match value.to_utf8() {
-            Some(v) =>
-            println!("retrieved utf8 value: {}", v),
-            None =>
-            println!("did not read valid utf-8 out of the db"),
+                Some(v) =>
+                    println!("retrieved utf8 value: {}", v),
+                None =>
+                    println!("did not read valid utf-8 out of the db"),
             }
-            })
-    .on_absent( || { println!("value not found") })
-        .on_error( |e| { println!("error retrieving value: {}", e) });
+        },
+        Err(e) => println!("error retrieving value: {}", e),
+        _ => panic!("value not present!"),
+    }
 
     assert!(db.delete(b"my key").is_ok());
 
@@ -94,17 +96,18 @@ fn custom_merge() {
         db.merge(b"k1", b"d").unwrap();
         db.merge(b"k1", b"efg").unwrap();
         db.merge(b"k1", b"h").unwrap();
-        db.get(b"k1").map( |value| {
+        match db.get(b"k1") {
+            Ok(Some(value)) => {
                 match value.to_utf8() {
-                Some(v) =>
-                println!("retrieved utf8 value: {}", v),
-                None =>
-                println!("did not read valid utf-8 out of the db"),
+                    Some(v) =>
+                        println!("retrieved utf8 value: {}", v),
+                    None =>
+                        println!("did not read valid utf-8 out of the db"),
                 }
-                })
-        .on_absent( || { println!("value not found") })
-            .on_error( |e| { println!("error retrieving value: {}", e) });
-
+            }
+            Err(e) => println!("error retrieving value: {}", e),
+            _ => panic!("value not present!"),
+        }
     }
     DB::destroy(&opts, path).is_ok();
 }
@@ -129,8 +132,7 @@ fn main() {
                 None => panic!("value corrupted"),
             }
         })
-            .on_absent( || { panic!("value not found") })
-            .on_error( |e| { panic!("error retrieving value: {}", e) });
+            .or_else( |e| { panic!("error retrieving value: {}", e) });
         db.delete(b"k1");
     }
 }

src/merge_operator.rs

@@ -21,7 +21,7 @@ use std::ptr;
 use std::slice;
 
 use rocksdb_options::Options;
-use rocksdb::{DB, DBResult, DBVector, Writable};
+use rocksdb::{DB, DBVector, Writable};
 
 pub struct MergeOperatorCallback {
     pub name: CString,
@@ -196,21 +196,24 @@ fn mergetest() {
         db.merge(b"k1", b"efg");
         let m = db.merge(b"k1", b"h");
         assert!(m.is_ok());
-        db.get(b"k1").map( |value| {
+        match db.get(b"k1") {
+            Ok(Some(value)) => {
                 match value.to_utf8() {
-                Some(v) =>
-                println!("retrieved utf8 value: {}", v),
-                None =>
-                println!("did not read valid utf-8 out of the db"),
+                    Some(v) =>
+                        println!("retrieved utf8 value: {}", v),
+                    None =>
+                        println!("did not read valid utf-8 out of the db"),
                 }
-                }).on_absent( || { println!("value not present!") })
-        .on_error( |e| { println!("error reading value")}); //: {", e) });
+            },
+            Err(e) => { println!("error reading value")},
+            _ => panic!("value not present"),
+        }
 
         assert!(m.is_ok());
-        let r: DBResult<DBVector, String> = db.get(b"k1");
-        assert!(r.unwrap().to_utf8().unwrap() == "abcdefgh");
+        let r: Result<Option<DBVector>, String> = db.get(b"k1");
+        assert!(r.unwrap().unwrap().to_utf8().unwrap() == "abcdefgh");
         assert!(db.delete(b"k1").is_ok());
-        assert!(db.get(b"k1").is_none());
+        assert!(db.get(b"k1").unwrap().is_none());
     }
     assert!(DB::destroy(&opts, path).is_ok());
 }

src/rocksdb.rs

@@ -327,11 +327,11 @@ impl DB {
         return Ok(())
     }
 
-    pub fn get(&self, key: &[u8]) -> DBResult<DBVector, String> {
+    pub fn get(&self, key: &[u8]) -> Result<Option<DBVector>, String> {
         unsafe {
             let readopts = rocksdb_ffi::rocksdb_readoptions_create();
             if readopts.0.is_null() {
-                return DBResult::Error("Unable to create rocksdb read \
+                return Err("Unable to create rocksdb read \
                     options.  This is a fairly trivial call, and its failure \
                     may be indicative of a mis-compiled or mis-loaded rocksdb \
                     library.".to_string());
@@ -345,22 +345,22 @@ impl DB {
                 key.as_ptr(), key.len() as size_t, val_len_ptr, err_ptr) as *mut u8;
             rocksdb_ffi::rocksdb_readoptions_destroy(readopts);
             if !err.is_null() {
-                return DBResult::Error(error_message(err));
+                return Err(error_message(err));
             }
             match val.is_null() {
-                true => DBResult::None,
+                true => Ok(None),
                 false => {
-                    DBResult::Some(DBVector::from_c(val, val_len))
+                    Ok(Some(DBVector::from_c(val, val_len)))
                 }
             }
         }
     }
 
-    pub fn get_cf(&self, cf: DBCFHandle, key: &[u8]) -> DBResult<DBVector, String> {
+    pub fn get_cf(&self, cf: DBCFHandle, key: &[u8]) -> Result<Option<DBVector>, String> {
         unsafe {
             let readopts = rocksdb_ffi::rocksdb_readoptions_create();
             if readopts.0.is_null() {
-                return DBResult::Error("Unable to create rocksdb read \
+                return Err("Unable to create rocksdb read \
                     options.  This is a fairly trivial call, and its failure \
                     may be indicative of a mis-compiled or mis-loaded rocksdb \
                     library.".to_string());
@@ -375,12 +375,12 @@ impl DB {
                 err_ptr) as *mut u8;
             rocksdb_ffi::rocksdb_readoptions_destroy(readopts);
             if !err.is_null() {
-                return DBResult::Error(error_message(err));
+                return Err(error_message(err));
             }
             match val.is_null() {
-                true => DBResult::None,
+                true => Ok(None),
                 false => {
-                    DBResult::Some(DBVector::from_c(val, val_len))
+                    Ok(Some(DBVector::from_c(val, val_len)))
                 }
             }
         }
@@ -691,76 +691,6 @@ impl DBVector {
     }
 }
 
-// DBResult exists because of the inherent difference between
-// an operational failure and the absence of a possible result.
-#[derive(Clone, PartialEq, PartialOrd, Eq, Ord, Debug)]
-pub enum DBResult<T, E> {
-    Some(T),
-    None,
-    Error(E),
-}
-
-impl <T, E> DBResult<T, E> {
-    pub fn map<U, F: FnOnce(T) -> U>(self, f: F) -> DBResult<U, E> {
-        match self {
-            DBResult::Some(x) => DBResult::Some(f(x)),
-            DBResult::None => DBResult::None,
-            DBResult::Error(e) => DBResult::Error(e),
-        }
-    }
-
-    pub fn unwrap(self) -> T {
-        match self {
-            DBResult::Some(x) => x,
-            DBResult::None =>
-                panic!("Attempted unwrap on DBResult::None"),
-            DBResult::Error(_) =>
-                panic!("Attempted unwrap on DBResult::Error"),
-        }
-    }
-
-    pub fn on_error<U, F: FnOnce(E) -> U>(self, f: F) -> DBResult<T, U> {
-        match self {
-            DBResult::Some(x) => DBResult::Some(x),
-            DBResult::None => DBResult::None,
-            DBResult::Error(e) => DBResult::Error(f(e)),
-        }
-    }
-
-    pub fn on_absent<F: FnOnce() -> ()>(self, f: F) -> DBResult<T, E> {
-        match self {
-            DBResult::Some(x) => DBResult::Some(x),
-            DBResult::None => {
-                f();
-                DBResult::None
-            },
-            DBResult::Error(e) => DBResult::Error(e),
-        }
-    }
-
-    pub fn is_some(self) -> bool {
-        match self {
-            DBResult::Some(_) => true,
-            DBResult::None => false,
-            DBResult::Error(_) => false,
-        }
-    }
-    pub fn is_none(self) -> bool {
-        match self {
-            DBResult::Some(_) => false,
-            DBResult::None => true,
-            DBResult::Error(_) => false,
-        }
-    }
-    pub fn is_error(self) -> bool {
-        match self {
-            DBResult::Some(_) => false,
-            DBResult::None => false,
-            DBResult::Error(_) => true,
-        }
-    }
-}
-
 #[test]
 fn external() {
     let path = "_rust_rocksdb_externaltest";
@@ -768,10 +698,10 @@ fn external() {
         let mut db = DB::open_default(path).unwrap();
         let p = db.put(b"k1", b"v1111");
         assert!(p.is_ok());
-        let r: DBResult<DBVector, String> = db.get(b"k1");
-        assert!(r.unwrap().to_utf8().unwrap() == "v1111");
+        let r: Result<Option<DBVector>, String> = db.get(b"k1");
+        assert!(r.unwrap().unwrap().to_utf8().unwrap() == "v1111");
         assert!(db.delete(b"k1").is_ok());
-        assert!(db.get(b"k1").is_none());
+        assert!(db.get(b"k1").unwrap().is_none());
     }
     let opts = Options::new();
     let result = DB::destroy(&opts, path);
@@ -797,20 +727,20 @@ fn writebatch_works() {
         let mut db = DB::open_default(path).unwrap();
         { // test put
             let mut batch = WriteBatch::new();
-            assert!(db.get(b"k1").is_none());
+            assert!(db.get(b"k1").unwrap().is_none());
             batch.put(b"k1", b"v1111");
-            assert!(db.get(b"k1").is_none());
+            assert!(db.get(b"k1").unwrap().is_none());
             let p = db.write(batch);
             assert!(p.is_ok());
-            let r: DBResult<DBVector, String> = db.get(b"k1");
-            assert!(r.unwrap().to_utf8().unwrap() == "v1111");
+            let r: Result<Option<DBVector>, String> = db.get(b"k1");
+            assert!(r.unwrap().unwrap().to_utf8().unwrap() == "v1111");
         }
         { // test delete
             let mut batch = WriteBatch::new();
             batch.delete(b"k1");
             let p = db.write(batch);
             assert!(p.is_ok());
-            assert!(db.get(b"k1").is_none());
+            assert!(db.get(b"k1").unwrap().is_none());
         }
     }
     let opts = Options::new();

test/test_column_family.rs

@@ -67,7 +67,7 @@ pub fn test_column_family() {
         };
         let cf1 = *db.cf_handle("cf1").unwrap();
         assert!(db.put_cf(cf1, b"k1", b"v1").is_ok());
-        assert!(db.get_cf(cf1, b"k1").unwrap().to_utf8().unwrap() == "v1");
+        assert!(db.get_cf(cf1, b"k1").unwrap().unwrap().to_utf8().unwrap() == "v1");
         let p = db.put_cf(cf1, b"k1", b"a");
         assert!(p.is_ok());
         db.merge_cf(cf1, b"k1", b"b").unwrap();
@@ -77,20 +77,23 @@ pub fn test_column_family() {
         let m = db.merge_cf(cf1, b"k1", b"h");
         println!("m is {:?}", m);
         // TODO assert!(m.is_ok());
-        db.get(b"k1").map( |value| {
+        match db.get(b"k1") {
+            Ok(Some(value)) => {
                 match value.to_utf8() {
-                Some(v) =>
-                println!("retrieved utf8 value: {}", v),
-                None =>
-                println!("did not read valid utf-8 out of the db"),
+                    Some(v) =>
+                        println!("retrieved utf8 value: {}", v),
+                    None =>
+                        println!("did not read valid utf-8 out of the db"),
                 }
-                }).on_absent( || { println!("value not present!") })
-        .on_error( |_| { println!("error reading value")}); //: {", e) });
+            },
+            Err(e) => println!("error reading value"),
+            _ => panic!("value not present!"),
+        }
 
         let _ = db.get_cf(cf1, b"k1");
         // TODO assert!(r.unwrap().to_utf8().unwrap() == "abcdefgh");
         assert!(db.delete(b"k1").is_ok());
-        assert!(db.get(b"k1").is_none());
+        assert!(db.get(b"k1").unwrap().is_none());
     }
     // TODO should be able to use writebatch ops with a cf
     {

test/test_multithreaded.rs

@@ -1,4 +1,4 @@
-use rocksdb::{Options, DB, Writable, DBResult};
+use rocksdb::{Options, DB, Writable};
 use std::thread;
 use std::sync::Arc;
 
@@ -31,7 +31,7 @@ pub fn test_multithreaded() {
         let j3 = thread::spawn(move|| {
             for _ in 1..N {
                 match db3.get(b"key") {
-                    DBResult::Some(v) => {
+                    Ok(Some(v)) => {
                         if &v[..] != b"value1" && &v[..] != b"value2" {
                             assert!(false);
                         }