add redis-compatible HSCAN/SSCAN/ZSCAN commands (#321)

cmd/ledis-cli/const.go

@@ -1,4 +1,4 @@
-//This file was generated by .tools/generate_commands.py on Sat Mar 14 2015 08:58:32 +0800
+//This file was generated by .tools/generate_commands.py on Sat Oct 28 2017 18:15:49 -0500 
 package main
 
 var helpCommands = [][]string{
@@ -43,6 +43,7 @@ var helpCommands = [][]string{
 	{"HMGET", "key field [field ...]", "Hash"},
 	{"HMSET", "key field value [field value ...]", "Hash"},
 	{"HPERSIST", "key", "Hash"},
+	{"HSCAN", "key cursor [MATCH match] [COUNT count] [ASC|DESC]", "Hash"},
 	{"HSET", "key field value", "Hash"},
 	{"HTTL", "key", "Hash"},
 	{"HVALS", "key", "Hash"},
@@ -96,6 +97,7 @@ var helpCommands = [][]string{
 	{"SMEMBERS", "key", "Set"},
 	{"SPERSIST", "key", "Set"},
 	{"SREM", "key member [member ...]", "Set"},
+	{"SSCAN", "key cursor [MATCH match] [COUNT count] [ASC|DESC]", "Set"},
 	{"STRLEN", "key", "KV"},
 	{"STTL", "key", "Set"},
 	{"SUNION", "key [key ...]", "Set"},
@@ -134,6 +136,7 @@ var helpCommands = [][]string{
 	{"ZREVRANGE", "key start stop [WITHSCORES]", "ZSet"},
 	{"ZREVRANGEBYSCORE", "key max min  [WITHSCORES][LIMIT offset count]", "ZSet"},
 	{"ZREVRANK", "key member", "ZSet"},
+	{"ZSCAN", "key cursor [MATCH match] [COUNT count] [ASC|DESC]", "ZSet"},
 	{"ZSCORE", "key member", "ZSet"},
 	{"ZTTL", "key", "ZSet"},
 	{"ZUNIONSTORE", "destkey numkeys key [key ...] [WEIGHTS weight [weight ...]] [AGGREGATE SUM|MIN|MAX]", "ZSet"},

doc/DiffRedis.md

@@ -32,13 +32,10 @@ ZSet only support int64 score, not double in Redis.
 
 ## Scan
 
-LedisDB supplies `xscan`, `xhscan`, `xsscan`, `xzscan` to fetch data iteratively and reverse iteratively.
+LedisDB supplies `xscan` instead of `scan` to fetch keys iteratively and reverse iteratively.
 
 ```
 XSCAN type cursor [MATCH match] [COUNT count]
-XHSCAN key cursor [MATCH match] [COUNT count]
-XSSCAN key cursor [MATCH match] [COUNT count]
-XZSCAN key cursor [MATCH match] [COUNT count]
 ```
 
 ## DUMP

doc/commands.json

@@ -115,6 +115,11 @@
         "group": "Hash",
         "readonly": false
     },
+    "HSCAN": {
+        "arguments": "key cursor [MATCH match] [COUNT count] [ASC|DESC]",
+        "group": "Hash",
+        "readonly": true
+    },
     "HPERSIST": {
         "arguments": "key",
         "group": "Hash",
@@ -310,6 +315,11 @@
         "group": "Set",
         "readonly": true
     },
+    "SSCAN": {
+        "arguments": "key cursor [MATCH match] [COUNT count] [ASC|DESC]",
+        "group": "Set",
+        "readonly": true
+    },
     "SREM": {
         "arguments": "key member [member ...]",
         "group": "Set",
@@ -450,6 +460,11 @@
         "group": "ZSet",
         "readonly": true
     },
+    "ZSCAN": {
+        "arguments": "key cursor [MATCH match] [COUNT count] [ASC|DESC]",
+        "group": "ZSet",
+        "readonly": true
+    },
     "ZSCORE": {
         "arguments": "key member",
         "group": "ZSet",

doc/commands.md

@@ -48,6 +48,7 @@ Most of the Ledisdb's commands are the same as Redis's, you can see the redis co
   - [HLEN key](#hlen-key)
   - [HMGET key field [field ...]](#hmget-key-field-field-)
   - [HMSET key field value [field value ...]](#hmset-key-field-value-field-value-)
+  - [HSCAN key cursor [MATCH match] [COUNT count] [ASC|DESC]](#hscan-key-cursor-match-match-count-count-asc|desc)
   - [HSET key field value](#hset-key-field-value)
   - [HVALS key](#hvals-key)
   - [HCLEAR key](#hclear-key)
@@ -88,6 +89,7 @@ Most of the Ledisdb's commands are the same as Redis's, you can see the redis co
   - [SISMEMBER  key member](#sismember--key-member)
   - [SMEMBERS key](#smembers-key)
   - [SREM  key member [member ...]](#srem--key-member-member-)
+  - [SSCAN key cursor [MATCH match] [COUNT count] [ASC|DESC]](#sscan-key-cursor-match-match-count-count-asc|desc)
   - [SUNION key [key ...]](#sunion-key-key-)
   - [SUNIONSTORE destination key [key]](#sunionstore-destination-key-key)
   - [SCLEAR key](#sclear-key)
@@ -112,6 +114,7 @@ Most of the Ledisdb's commands are the same as Redis's, you can see the redis co
   - [ZREVRANGE key start stop [WITHSCORES]](#zrevrange-key-start-stop-withscores)
   - [ZREVRANGEBYSCORE  key max min [WITHSCORES] [LIMIT offset count]](#zrevrangebyscore--key-max-min-withscores-limit-offset-count)
   - [ZREVRANK key member](#zrevrank-key-member)
+  - [ZSCAN key cursor [MATCH match] [COUNT count] [ASC|DESC]](#zscan-key-cursor-match-match-count-count-asc|desc)
   - [ZSCORE key member](#zscore-key-member)
   - [ZCLEAR key](#zclear-key)
   - [ZMCLEAR key [key ...]](#zmclear-key-key-)
@@ -730,6 +733,12 @@ ledis> HMGET myhash field1 field2
 2) "world"
 ```
 
+### HSCAN key cursor [MATCH match] [COUNT count] [ASC|DESC]
+
+Same like XHSCAN, but made redis compatible.
+Meaning that the initial cursor has to be `"0"`,
+and the final cursor will be `"0"` as well.
+
 ### HSET key field value
 
 Sets field in the hash stored at key to value. If key does not exists, a new hash key is created.
@@ -1489,6 +1498,12 @@ ledis> SMEMBERS myset
 2) "two"
 ```
 
+### SSCAN key cursor [MATCH match] [COUNT count] [ASC|DESC]
+
+Same like XSSCAN, but made redis compatible.
+Meaning that the initial cursor has to be `"0"`,
+and the final cursor will be `"0"` as well.
+
 ### SUNION key [key ...]
 
 Returns the members of the set resulting from the union of all the given sets.
@@ -2089,6 +2104,12 @@ ledis> ZSCORE myzset 'one'
 1
 ```
 
+### ZSCAN key cursor [MATCH match] [COUNT count] [ASC|DESC]
+
+Same like XZSCAN, but made redis compatible.
+Meaning that the initial cursor has to be `"0"`,
+and the final cursor will be `"0"` as well.
+
 ### ZCLEAR key
 Delete the specified  key
 

server/cmd_scan.go

@@ -1,6 +1,7 @@
 package server
 
 import (
+	"bytes"
 	"fmt"
 	"strconv"
 	"strings"
@@ -10,7 +11,7 @@ import (
 	"github.com/siddontang/ledisdb/ledis"
 )
 
-func parseScanArgs(args [][]byte) (cursor []byte, match string, count int, desc bool, err error) {
+func parseXScanArgs(args [][]byte) (cursor []byte, match string, count int, desc bool, err error) {
 	cursor = args[0]
 
 	args = args[1:]
@@ -56,8 +57,21 @@ func parseScanArgs(args [][]byte) (cursor []byte, match string, count int, desc
 	return
 }
 
+func parseScanArgs(args [][]byte) (cursor []byte, match string, count int, desc bool, err error) {
+	cursor, match, count, desc, err = parseXScanArgs(args)
+	if bytes.Compare(cursor, nilCursorRedis) == 0 {
+		cursor = nilCursorLedis
+	}
+	return
+}
+
+type scanCommandGroup struct {
+	lastCursor []byte
+	parseArgs  func(args [][]byte) (cursor []byte, match string, count int, desc bool, err error)
+}
+
 // XSCAN type cursor [MATCH match] [COUNT count] [ASC|DESC]
-func xscanCommand(c *client) error {
+func (scg scanCommandGroup) xscanCommand(c *client) error {
 	args := c.args
 
 	if len(args) < 2 {
@@ -80,7 +94,7 @@ func xscanCommand(c *client) error {
 		return fmt.Errorf("invalid key type %s", args[0])
 	}
 
-	cursor, match, count, desc, err := parseScanArgs(args[1:])
+	cursor, match, count, desc, err := scg.parseArgs(args[1:])
 
 	if err != nil {
 		return err
@@ -100,7 +114,7 @@ func xscanCommand(c *client) error {
 
 	data := make([]interface{}, 2)
 	if len(ay) < count {
-		data[0] = []byte("")
+		data[0] = scg.lastCursor
 	} else {
 		data[0] = ay[len(ay)-1]
 	}
@@ -110,7 +124,7 @@ func xscanCommand(c *client) error {
 }
 
 // XHSCAN key cursor [MATCH match] [COUNT count] [ASC|DESC]
-func xhscanCommand(c *client) error {
+func (scg scanCommandGroup) xhscanCommand(c *client) error {
 	args := c.args
 
 	if len(args) < 2 {
@@ -119,7 +133,7 @@ func xhscanCommand(c *client) error {
 
 	key := args[0]
 
-	cursor, match, count, desc, err := parseScanArgs(args[1:])
+	cursor, match, count, desc, err := scg.parseArgs(args[1:])
 
 	if err != nil {
 		return err
@@ -139,7 +153,7 @@ func xhscanCommand(c *client) error {
 
 	data := make([]interface{}, 2)
 	if len(ay) < count {
-		data[0] = []byte("")
+		data[0] = scg.lastCursor
 	} else {
 		data[0] = ay[len(ay)-1].Field
 	}
@@ -157,7 +171,7 @@ func xhscanCommand(c *client) error {
 }
 
 // XSSCAN key cursor [MATCH match] [COUNT count] [ASC|DESC]
-func xsscanCommand(c *client) error {
+func (scg scanCommandGroup) xsscanCommand(c *client) error {
 	args := c.args
 
 	if len(args) < 2 {
@@ -166,7 +180,7 @@ func xsscanCommand(c *client) error {
 
 	key := args[0]
 
-	cursor, match, count, desc, err := parseScanArgs(args[1:])
+	cursor, match, count, desc, err := scg.parseArgs(args[1:])
 
 	if err != nil {
 		return err
@@ -186,7 +200,7 @@ func xsscanCommand(c *client) error {
 
 	data := make([]interface{}, 2)
 	if len(ay) < count {
-		data[0] = []byte("")
+		data[0] = scg.lastCursor
 	} else {
 		data[0] = ay[len(ay)-1]
 	}
@@ -198,7 +212,7 @@ func xsscanCommand(c *client) error {
 }
 
 // XZSCAN key cursor [MATCH match] [COUNT count] [ASC|DESC]
-func xzscanCommand(c *client) error {
+func (scg scanCommandGroup) xzscanCommand(c *client) error {
 	args := c.args
 
 	if len(args) < 2 {
@@ -207,7 +221,7 @@ func xzscanCommand(c *client) error {
 
 	key := args[0]
 
-	cursor, match, count, desc, err := parseScanArgs(args[1:])
+	cursor, match, count, desc, err := scg.parseArgs(args[1:])
 
 	if err != nil {
 		return err
@@ -227,7 +241,7 @@ func xzscanCommand(c *client) error {
 
 	data := make([]interface{}, 2)
 	if len(ay) < count {
-		data[0] = []byte("")
+		data[0] = scg.lastCursor
 	} else {
 		data[0] = ay[len(ay)-1].Member
 	}
@@ -244,9 +258,23 @@ func xzscanCommand(c *client) error {
 	return nil
 }
 
+var (
+	xScanGroup = scanCommandGroup{nilCursorLedis, parseXScanArgs}
+	scanGroup  = scanCommandGroup{nilCursorRedis, parseScanArgs}
+)
+
+var (
+	nilCursorLedis = []byte("")
+	nilCursorRedis = []byte("0")
+)
+
 func init() {
-	register("xscan", xscanCommand)
+	register("hscan", scanGroup.xhscanCommand)
-	register("xhscan", xhscanCommand)
+	register("sscan", scanGroup.xsscanCommand)
-	register("xsscan", xsscanCommand)
+	register("zscan", scanGroup.xzscanCommand)
-	register("xzscan", xzscanCommand)
+
+	register("xscan", xScanGroup.xscanCommand)
+	register("xhscan", xScanGroup.xhscanCommand)
+	register("xsscan", xScanGroup.xsscanCommand)
+	register("xzscan", xScanGroup.xzscanCommand)
 }

server/cmd_scan_test.go

@@ -32,7 +32,6 @@ func TestScan(t *testing.T) {
 	testListKeyScan(t, c)
 	testZSetKeyScan(t, c)
 	testSetKeyScan(t, c)
-
 }
 
 func checkScanValues(t *testing.T, ay interface{}, values ...interface{}) {
@@ -47,7 +46,7 @@ func checkScanValues(t *testing.T, ay interface{}, values ...interface{}) {
 
 	for i, v := range a {
 		if string(v) != fmt.Sprintf("%v", values[i]) {
-			t.Fatal(fmt.Sprintf("%d %s != %v", string(v), values[i]))
+			t.Fatal(fmt.Sprintf("%d %s != %v", i, string(v), values[i]))
 		}
 	}
 }
@@ -72,7 +71,6 @@ func checkScan(t *testing.T, c *goredis.Client, tp string) {
 	} else {
 		checkScanValues(t, ay[1], 5, 6, 7, 8, 9)
 	}
-
 }
 
 func testKVScan(t *testing.T, c *goredis.Client) {
@@ -125,7 +123,7 @@ func testSetKeyScan(t *testing.T, c *goredis.Client) {
 	checkScan(t, c, "SET")
 }
 
-func TestHashScan(t *testing.T) {
+func TestXHashScan(t *testing.T) {
 	c := getTestConn()
 	defer c.Close()
 
@@ -141,7 +139,23 @@ func TestHashScan(t *testing.T) {
 	}
 }
 
-func TestSetScan(t *testing.T) {
+func TestHashScan(t *testing.T) {
+	c := getTestConn()
+	defer c.Close()
+
+	key := "scan_hash"
+	c.Do("HMSET", key, "a", 1, "b", 2)
+
+	if ay, err := goredis.Values(c.Do("HSCAN", key, "0")); err != nil {
+		t.Fatal(err)
+	} else if len(ay) != 2 {
+		t.Fatal(len(ay))
+	} else {
+		checkScanValues(t, ay[1], "a", 1, "b", 2)
+	}
+}
+
+func TestXSetScan(t *testing.T) {
 	c := getTestConn()
 	defer c.Close()
 
@@ -155,10 +169,25 @@ func TestSetScan(t *testing.T) {
 	} else {
 		checkScanValues(t, ay[1], "a", "b")
 	}
-
 }
 
-func TestZSetScan(t *testing.T) {
+func TestSetScan(t *testing.T) {
+	c := getTestConn()
+	defer c.Close()
+
+	key := "scan_set"
+	c.Do("SADD", key, "a", "b")
+
+	if ay, err := goredis.Values(c.Do("SSCAN", key, "0")); err != nil {
+		t.Fatal(err)
+	} else if len(ay) != 2 {
+		t.Fatal(len(ay))
+	} else {
+		checkScanValues(t, ay[1], "a", "b")
+	}
+}
+
+func TestXZSetScan(t *testing.T) {
 	c := getTestConn()
 	defer c.Close()
 
@@ -172,5 +201,21 @@ func TestZSetScan(t *testing.T) {
 	} else {
 		checkScanValues(t, ay[1], "a", 1, "b", 2)
 	}
+}
+
+func TestZSetScan(t *testing.T) {
+	c := getTestConn()
+	defer c.Close()
+
+	key := "scan_zset"
+	c.Do("ZADD", key, 1, "a", 2, "b")
+
+	if ay, err := goredis.Values(c.Do("XZSCAN", key, "0")); err != nil {
+		t.Fatal(err)
+	} else if len(ay) != 2 {
+		t.Fatal(len(ay))
+	} else {
+		checkScanValues(t, ay[1], "a", 1, "b", 2)
+	}
 
 }