add 2.8.0 new methods: scan/sscan/hscan/zscan

2 files changed, 131 insertions, 1 deletions

diff --git a/redis/client.py b/redis/client.py
index 79a2a54..d133989 100644
--- a/redis/client.py
+++ b/redis/client.py
@@ -240,6 +240,21 @@ def parse_script(response, **options):
     return response
 
 
+def parse_scan(response, **options):
+    return response
+
+
+def parse_hscan(response, **options):
+    cursor, r = response
+    return [cursor, r and pairs_to_dict(r) or {}]
+
+
+def parse_zscan(response, **options):
+    score_cast_func = options.get('score_cast_func', float)
+    it = iter(response[1])
+    return [response[0], list(izip(it, imap(score_cast_func, it)))]
+
+
 class StrictRedis(object):
     """
     Implementation of the Redis protocol.
@@ -304,7 +319,11 @@ class StrictRedis(object):
             'SCRIPT': parse_script,
             'SET': lambda r: r and nativestr(r) == 'OK',
             'TIME': lambda x: (int(x[0]), int(x[1])),
-            'SENTINEL': parse_sentinel
+            'SENTINEL': parse_sentinel,
+            'SCAN': parse_scan,
+            'SSCAN': parse_scan,
+            'HSCAN': parse_hscan,
+            'ZSCAN': parse_zscan
         }
     )
 
@@ -1153,6 +1172,78 @@ class StrictRedis(object):
         options = {'groups': len(get) if groups else None}
         return self.execute_command('SORT', *pieces, **options)
 
+    #### SCAN COMMANDS ####
+    def scan(self, cursor, match=None, count=None):
+        """
+        Scan and return (nextcursor, keys)
+
+        ``match`` allows for filtering the keys by pattern
+
+        ``count`` allows for hint the minimum number of returns
+        """
+        pieces = [cursor]
+        if match is not None:
+            pieces.append('MATCH')
+            pieces.append(match)
+        if count is not None:
+            pieces.append('COUNT')
+            pieces.append(count)
+        return self.execute_command('SCAN', *pieces)
+
+    def sscan(self, name, cursor, match=None, count=None):
+        """
+        Scan and return (nextcursor, membersofset)
+
+        ``match`` allows for filtering the keys by pattern
+
+        ``count`` allows for hint the minimum number of returns
+        """
+        pieces = [name, cursor]
+        if match is not None:
+            pieces.append('MATCH')
+            pieces.append(match)
+        if count is not None:
+            pieces.append('COUNT')
+            pieces.append(count)
+        return self.execute_command('SSCAN', *pieces)
+
+    def hscan(self, name, cursor, match=None, count=None):
+        """
+        Scan and return (nextcursor, dict)
+
+        ``match`` allows for filtering the keys by pattern
+
+        ``count`` allows for hint the minimum number of returns
+        """
+        pieces = [name, cursor]
+        if match is not None:
+            pieces.append('MATCH')
+            pieces.append(match)
+        if count is not None:
+            pieces.append('COUNT')
+            pieces.append(count)
+        return self.execute_command('HSCAN', *pieces)
+
+    def zscan(self, name, cursor, match=None, count=None, score_cast_func=float):
+        """
+        Scan and return (nextcursor, pairs)
+
+        ``match`` allows for filtering the keys by pattern
+
+        ``count`` allows for hint the minimum number of returns
+
+        ``score_cast_func`` a callable used to cast the score return value
+        """
+        pieces = [name, cursor]
+        if match is not None:
+            pieces.append('MATCH')
+            pieces.append(match)
+        if count is not None:
+            pieces.append('COUNT')
+            pieces.append(count)
+        options = {'score_cast_func': score_cast_func}
+        return self.execute_command('ZSCAN', *pieces, **options)
+
     #### SET COMMANDS ####
     def sadd(self, name, *values):
         "Add ``value(s)`` to set ``name``"
diff --git a/tests/test_commands.py b/tests/test_commands.py
index 24bf11d..b82f0f5 100644
--- a/tests/test_commands.py
+++ b/tests/test_commands.py
@@ -635,6 +635,45 @@ class TestRedisCommands(object):
         assert r.rpushx('a', '4') == 4
         assert r.lrange('a', 0, -1) == [b('1'), b('2'), b('3'), b('4')]
 
+    ### SCAN COMMANDS ###
+    @skip_if_server_version_lt('2.8.0')
+    def test_scan(self, r):
+        r.set('a', 1)
+        r.set('b', 2)
+        r.set('c', 3)
+        cursor, keys = r.scan(0)
+        assert cursor == b('0')
+        assert set(keys) == set([b('a'), b('b'), b('c')])
+        _, keys = r.scan(0, match='a')
+        assert set(keys) == set([b('a')])
+
+    @skip_if_server_version_lt('2.8.0')
+    def test_sscan(self, r):
+        r.sadd('a', 1, 2, 3)
+        cursor, members = r.sscan('a', 0)
+        assert cursor == b('0')
+        assert set(members) == set([b('1'), b('2'), b('3')])
+        _, members = r.sscan('a', 0, match=b('1'))
+        assert set(members) == set([b('1')])
+
+    @skip_if_server_version_lt('2.8.0')
+    def test_hscan(self, r):
+        r.hmset('a', dict(a=1, b=2, c=3))
+        cursor, dic = r.hscan('a', 0)
+        assert cursor == b('0')
+        assert dic == dict(a=b('1'), b=b('2'), c=b('3'))
+        _, dic = r.hscan('a', 0, match='a')
+        assert dic == dict(a=b('1'))
+
+    @skip_if_server_version_lt('2.8.0')
+    def test_zscan(self, r):
+        r.zadd('a', 'a', 1, 'b', 2, 'c', 3)
+        cursor, pairs = r.zscan('a', 0)
+        assert cursor == b('0')
+        assert set(pairs) == set([(b('a'), 1), (b('b'), 2), (b('c'), 3)])
+        _, pairs = r.zscan('a', 0, match='a')
+        assert set(pairs) == set([(b('a'), 1)])
+
     ### SET COMMANDS ###
     def test_sadd(self, r):
         members = set([b('1'), b('2'), b('3')])