Null support and Makefile

.gitignore

@@ -1,2 +1,4 @@
 *.so
+*.dummy
 /postgres
+/test*

Makefile

@@ -0,0 +1,24 @@
+RUSTC ?= rustc
+RUSTFLAGS += -L.
+
+.PHONY: all
+all: sql.dummy postgres.dummy test_postgres sqlite3.dummy
+
+sql.dummy: src/sql/lib.rs
+	$(RUSTC) $(RUSTFLAGS) --lib $< -o $@
+	touch $@
+
+postgres.dummy: src/postgres/lib.rs sql.dummy
+	$(RUSTC) $(RUSTFLAGS) --lib src/postgres/lib.rs -o $@
+	touch $@
+
+test_postgres: src/postgres/test.rs postgres.dummy
+	$(RUSTC) $(RUSTFLAGS) --test src/postgres/test.rs -o $@
+
+sqlite3.dummy: src/sqlite3/lib.rs sql.dummy
+	$(RUSTC) $(RUSTFLAGS) --lib src/sqlite3/lib.rs -o $@
+	touch $@
+
+.PHONY: clean
+clean:
+	rm *.dummy *.so

src/postgres/lib.rs

@@ -47,6 +47,8 @@ mod ffi {
         fn PQnfields(result: *PGresult) -> c_int;
         fn PQnparams(result: *PGresult) -> c_int;
         fn PQcmdTuples(result: *PGresult) -> *c_char;
+        fn PQgetisnull(result: *PGresult, row_number: c_int, col_number: c_int)
+                       -> c_int;
         fn PQgetvalue(result: *PGresult, row_number: c_int, col_number: c_int)
                       -> *c_char;
     }
@@ -242,6 +244,18 @@ impl<'self> PostgresStatement<'self> {
     }
 }
 
+fn as_c_str_array<T>(array: &[~str], blk: &fn(**c_char) -> T) -> T {
+    let mut c_array: ~[*c_char] = vec::with_capacity(array.len() + 1);
+    for s in array.iter() {
+        // DANGER, WILL ROBINSON
+        do s.as_c_str |c_s| {
+            c_array.push(c_s);
+        }
+    }
+    c_array.push(ptr::null());
+    blk(vec::raw::to_ptr(c_array))
+}
+
 pub struct PostgresResult {
     priv result: *ffi::PGresult
 }
@@ -275,6 +289,21 @@ impl PostgresResult {
     fn num_params(&self) -> uint {
         unsafe { ffi::PQnparams(self.result) as uint }
     }
+
+    fn is_null(&self, row: uint, col: uint) -> bool {
+        unsafe {
+            ffi::PQgetisnull(self.result, row as c_int, col as c_int) == 1
+        }
+    }
+
+    fn get_value(&self, row: uint, col: uint) -> ~str {
+        unsafe {
+            let raw_s = ffi::PQgetvalue(self.result,
+                                        row as c_int,
+                                        col as c_int);
+            str::raw::from_c_str(raw_s)
+        }
+    }
 }
 
 impl Container for PostgresResult {
@@ -345,37 +374,84 @@ impl<'self> Container for PostgresRow<'self> {
     }
 }
 
-impl<'self, T: FromStr> Index<uint, Option<T>> for PostgresRow<'self> {
-    fn index(&self, idx: &uint) -> Option<T> {
+impl<'self, T: FromSql> Index<uint, T> for PostgresRow<'self> {
+    fn index(&self, idx: &uint) -> T {
         self.get(*idx)
     }
 }
 
 impl<'self> PostgresRow<'self> {
-    pub fn get<T: FromStr>(&self, idx: uint) -> Option<T> {
+    fn is_null(&self, col: uint) -> bool {
+        self.result.is_null(self.row, col)
+    }
+
+    fn get_value(&self, col: uint) -> ~str {
+        self.result.get_value(self.row, col)
+    }
+}
+
+impl<'self> PostgresRow<'self> {
+    pub fn get<T: FromSql>(&self, idx: uint) -> T {
         if idx >= self.len() {
             fail!("Out of bounds access");
         }
-
-        let s = unsafe {
-            let raw_s = ffi::PQgetvalue(self.result.result,
-                                        self.row as c_int,
-                                        idx as c_int);
-            str::raw::from_c_str(raw_s)
-        };
-
-        FromStr::from_str(s)
+        FromSql::from_sql(self, idx)
     }
 }
 
-fn as_c_str_array<T>(array: &[~str], blk: &fn(**c_char) -> T) -> T {
-    let mut c_array: ~[*c_char] = vec::with_capacity(array.len() + 1);
-    for s in array.iter() {
-        // DANGER, WILL ROBINSON
-        do s.as_c_str |c_s| {
-            c_array.push(c_s);
+pub trait FromSql {
+    fn from_sql(row: &PostgresRow, idx: uint) -> Self;
+}
+
+macro_rules! from_str_impl(
+    ($t:ty) => (
+        impl FromSql for $t {
+            fn from_sql(row: &PostgresRow, idx: uint) -> $t {
+                if row.is_null(idx) {
+                    fail!("Row is NULL");
+                }
+                FromStr::from_str(row.get_value(idx)).get()
+            }
         }
-    }
-    c_array.push(ptr::null());
-    blk(vec::raw::to_ptr(c_array))
-}
+    )
+)
+
+macro_rules! option_impl(
+    ($t:ty) => (
+        impl FromSql for Option<$t> {
+            fn from_sql(row: &PostgresRow, idx: uint) -> Option<$t> {
+                match row.is_null(idx) {
+                    true => None,
+                    false => Some(FromSql::from_sql(row, idx))
+                }
+            }
+        }
+    )
+)
+
+from_str_impl!(int)
+option_impl!(int)
+from_str_impl!(i8)
+option_impl!(i8)
+from_str_impl!(i16)
+option_impl!(i16)
+from_str_impl!(i32)
+option_impl!(i32)
+from_str_impl!(i64)
+option_impl!(i64)
+from_str_impl!(uint)
+option_impl!(uint)
+from_str_impl!(u8)
+option_impl!(u8)
+from_str_impl!(u16)
+option_impl!(u16)
+from_str_impl!(u32)
+option_impl!(u32)
+from_str_impl!(u64)
+option_impl!(u64)
+from_str_impl!(float)
+option_impl!(float)
+from_str_impl!(f32)
+option_impl!(f32)
+from_str_impl!(f64)
+option_impl!(f64)

src/postgres/test.rs

@@ -38,10 +38,26 @@ fn test_params() {
         chk!(conn.update("INSERT INTO basic (id) VALUES ($1)", [~"101"]));
 
         let res = chk!(conn.query("SELECT id from basic WHERE id = $1", [~"101"]));
-        assert_eq!(1, res.len());
-        assert_eq!(1, res.get(0).len());
         assert_eq!(Some(101), res.get(0)[0]);
 
         Err::<(), ~str>(~"")
     };
 }
+
+#[test]
+fn test_null() {
+    let conn = chk!(PostgresConnection::new("postgres://postgres@localhost"));
+
+    do conn.in_transaction |conn| {
+        chk!(conn.update("CREATE TABLE basic (id INT PRIMARY KEY, foo INT)",
+                         []));
+        chk!(conn.update("INSERT INTO basic (id, foo) VALUES ($1, NULL), ($2, $3)",
+                         [~"101", ~"102", ~"0"]));
+
+        let res = chk!(conn.query("SELECT foo from basic ORDER BY id", []));
+        assert_eq!(None, res.get(0).get::<Option<int>>(0));
+        assert_eq!(Some(0), res.get(1).get::<Option<int>>(0));
+
+        Err::<(), ~str>(~"")
+    };
+}

src/sql/lib.rs

@@ -1,27 +1,23 @@
 
-pub trait SqlConnection<'self, S: SqlStatement> {
-    fn new(uri: &str) -> ~Self;
-
-    fn prepare(&self, query: &str) -> ~S<'self>;
+pub trait SqlConnection<Row, It, Res, S: SqlStatement<Row, It, Res>> {
+    fn new(uri: &str) -> Result<~Self, ~str>;
+    fn prepare<'a>(&'a self, query: &str) -> Result<~S, ~str>;
 }
 
-pub trait SqlStatement {
-    fn query<T>(&self, params: &[@SqlType],
-                blk: &fn(&SqlResult) -> Result<T, ~str>)
+pub trait SqlStatement<Row, It, R: SqlResult<Row, It>> {
+    fn query<T>(&self, params: &[~str], blk: &fn(&R) -> Result<T, ~str>)
                 -> Result<T, ~str>;
-
-    fn update(&self, params: &[@SqlType]) -> Result<uint, ~str>;
+    fn update(&self, params: &[~str]) -> Result<uint, ~str>;
 }
 
 pub trait SqlResult<R: SqlRow, I: Iterator<R>>: Container {
     fn iter(&self) -> I;
 }
 
-pub trait SqlRow {
-    fn get<T: SqlType>(&self) -> Option<T>;
+pub trait SqlRow: Container {
+    fn get<T: FromSql<Self>>(&self, index: uint) -> Option<T>;
 }
 
-pub enum SqlType {
-    Int(int),
-    Uint(uint),
+pub trait FromSql<R/*: SqlRow*/> {
+    fn from_sql(row: &R, column: uint) -> Option<Self>;
 }

src/sqlite3/lib.rs

@@ -2,7 +2,6 @@ use std::libc::c_int;
 use std::ptr;
 use std::str;
 use std::vec;
-use std::uint;
 
 mod ffi {
     use std::libc::{c_char, c_int, c_void};
@@ -165,7 +164,7 @@ impl<'self> PreparedStatement<'self> {
     }
 
     fn bind_params(&self, params: &[@SqlType]) -> Result<(), ~str> {
-        for params.iter().enumerate().advance |(idx, param)| {
+        for (idx, param) in params.iter().enumerate() {
             let ret = match param.to_sql_str() {
                 Some(val) => do val.as_c_str |c_param| {
                     unsafe {
@@ -246,7 +245,7 @@ impl<'self> Row<'self> {
         let count = unsafe { ffi::sqlite3_column_count(stmt.stmt) as uint};
         let mut row = Row {stmt: stmt, cols: vec::with_capacity(count)};
 
-        for uint::range(0, count) |i| {
+        for i in range(0, count) {
             let typ = unsafe {
                 ffi::sqlite3_column_type(stmt.stmt, i as c_int)
             };