refactored all functions to use the command registry

13 files changed, 408 insertions, 1 deletions

diff --git a/pkg/commands/command-registry.go b/pkg/commands/command-registry.go
index baf7133..068fe7c 100644
--- a/pkg/commands/command-registry.go
+++ b/pkg/commands/command-registry.go
@@ -4,6 +4,13 @@ import (
 	"errors"
 	"redisClone/pkg/core"
 )
+
+var dbInstance core.RedisDB
+
+func SetDB(db core.RedisDB) {
+	dbInstance = db
+}
+
 func SingleKey(args []string) []string {
     return []string{args[1]}
 }
@@ -16,6 +23,10 @@ func NoKeys(args []string) []string {
     return nil
 }
 
+func RenameKeys(args []string) []string {
+	return []string{args[1], args[2]}
+}
+
 type CommandDef struct{
 	MinArgs int
 	ExtractKeys func(args []string)[]string
@@ -72,7 +83,7 @@ var Registry = map[string]CommandDef{
     },
     "RENAME": {
         MinArgs:     3,
-        ExtractKeys: SingleKey,
+        ExtractKeys: RenameKeys,
         Execute: Rename,
     },
     "RPUSH": {
@@ -100,4 +111,64 @@ var Registry = map[string]CommandDef{
         ExtractKeys: SingleKey,
         Execute: Lrange,
     },
+    "FLUSHALL": {
+        MinArgs:     1,
+        ExtractKeys: NoKeys,
+        Execute:     Flushall,
+    },
+    "EXPIRE": {
+        MinArgs:     3,
+        ExtractKeys: SingleKey,
+        Execute:     Expire,
+    },
+    "HSET": {
+        MinArgs:     4,
+        ExtractKeys: SingleKey,
+        Execute:     Hset,
+    },
+    "HGET": {
+        MinArgs:     3,
+        ExtractKeys: SingleKey,
+        Execute:     Hget,
+    },
+    "HGETALL": {
+        MinArgs:     2,
+        ExtractKeys: SingleKey,
+        Execute:     Hgetall,
+    },
+    "HKEYS": {
+        MinArgs:     2,
+        ExtractKeys: SingleKey,
+        Execute:     Hkeys,
+    },
+    "HVALUES": {
+        MinArgs:     2,
+        ExtractKeys: SingleKey,
+        Execute:     Hvalues,
+    },
+    "TYPE": {
+        MinArgs:     2,
+        ExtractKeys: SingleKey,
+        Execute:     Type,
+    },
+    "DBSIZE": {
+        MinArgs:     1,
+        ExtractKeys: NoKeys,
+        Execute:     Dbsize,
+    },
+    "KEYS": {
+        MinArgs:     2,
+        ExtractKeys: NoKeys,
+        Execute:     Keys,
+    },
+    "LREM": {
+        MinArgs:     4,
+        ExtractKeys: SingleKey,
+        Execute:     Lrem,
+    },
+    "PING": {
+        MinArgs:     1,
+        ExtractKeys: NoKeys,
+        Execute:     Ping,
+    },
 }
\ No newline at end of file
diff --git a/pkg/commands/dbsize.go b/pkg/commands/dbsize.go
new file mode 100644
index 0000000..dbe39a4
--- /dev/null
+++ b/pkg/commands/dbsize.go
@@ -0,0 +1,15 @@
+package commands
+
+import (
+	"redisClone/pkg/core"
+)
+
+func Dbsize(args []string, getShard func(k string) *core.Shard) interface{} {
+	return dbInstance.ExecuteReadAll(func(shards []*core.Shard) interface{} {
+		count := 0
+		for _, shard := range shards {
+			count += len(shard.Data)
+		}
+		return count
+	})
+}
diff --git a/pkg/commands/expire.go b/pkg/commands/expire.go
new file mode 100644
index 0000000..4337e83
--- /dev/null
+++ b/pkg/commands/expire.go
@@ -0,0 +1,26 @@
+package commands
+
+import (
+	"errors"
+	"redisClone/pkg/core"
+	"strconv"
+	"time"
+)
+
+func Expire(args []string, getShard func(k string) *core.Shard) interface{} {
+	key := args[1]
+	seconds, err := strconv.Atoi(args[2])
+	if err != nil {
+		return errors.New("value is not an integer")
+	}
+
+	s := getShard(key)
+	item, exists := s.Data[key]
+	if !exists {
+		return 0
+	}
+	expiry := time.Now().Add(time.Duration(seconds) * time.Second)
+	item.ExpiresAt = &expiry
+	s.Data[key] = item
+	return 1
+}
diff --git a/pkg/commands/flushall.go b/pkg/commands/flushall.go
new file mode 100644
index 0000000..9f1316a
--- /dev/null
+++ b/pkg/commands/flushall.go
@@ -0,0 +1,14 @@
+package commands
+
+import (
+	"redisClone/pkg/core"
+)
+
+func Flushall(args []string, getShard func(k string) *core.Shard) interface{} {
+	return dbInstance.ExecuteAll(func(shards []*core.Shard) interface{} {
+		for _, shard := range shards {
+			shard.Data = make(map[string]core.Item)
+		}
+		return core.SimpleString("OK")
+	})
+}
diff --git a/pkg/commands/hget.go b/pkg/commands/hget.go
new file mode 100644
index 0000000..7d16808
--- /dev/null
+++ b/pkg/commands/hget.go
@@ -0,0 +1,25 @@
+package commands
+
+import (
+	"errors"
+	"redisClone/pkg/core"
+)
+
+func Hget(args []string, getShard func(k string) *core.Shard) interface{} {
+	key := args[1]
+	field := args[2]
+	s := getShard(key)
+	item, exists := s.Data[key]
+	if !exists {
+		return nil
+	}
+	hash, ok := item.Value.(map[string]string)
+	if !ok {
+		return errors.New("WRONGTYPE Operation against a key holding the wrong kind of value")
+	}
+	val, found := hash[field]
+	if !found {
+		return nil
+	}
+	return val
+}
diff --git a/pkg/commands/hgetall.go b/pkg/commands/hgetall.go
new file mode 100644
index 0000000..02b3e3f
--- /dev/null
+++ b/pkg/commands/hgetall.go
@@ -0,0 +1,20 @@
+package commands
+
+import (
+	"errors"
+	"redisClone/pkg/core"
+)
+
+func Hgetall(args []string, getShard func(k string) *core.Shard) interface{} {
+	key := args[1]
+	s := getShard(key)
+	item, exists := s.Data[key]
+	if !exists {
+		return nil
+	}
+	hash, ok := item.Value.(map[string]string)
+	if !ok {
+		return errors.New("WRONGTYPE Operation against a key holding the wrong kind of value")
+	}
+	return hash
+}
diff --git a/pkg/commands/hkeys.go b/pkg/commands/hkeys.go
new file mode 100644
index 0000000..09a5d97
--- /dev/null
+++ b/pkg/commands/hkeys.go
@@ -0,0 +1,24 @@
+package commands
+
+import (
+	"errors"
+	"redisClone/pkg/core"
+)
+
+func Hkeys(args []string, getShard func(k string) *core.Shard) interface{} {
+	key := args[1]
+	s := getShard(key)
+	item, exists := s.Data[key]
+	if !exists {
+		return nil
+	}
+	hash, ok := item.Value.(map[string]string)
+	if !ok {
+		return errors.New("WRONGTYPE Operation against a key holding the wrong kind of value")
+	}
+	keys := make([]string, 0, len(hash))
+	for k := range hash {
+		keys = append(keys, k)
+	}
+	return keys
+}
diff --git a/pkg/commands/hset.go b/pkg/commands/hset.go
new file mode 100644
index 0000000..33f992f
--- /dev/null
+++ b/pkg/commands/hset.go
@@ -0,0 +1,32 @@
+package commands
+
+import (
+	"errors"
+	"redisClone/pkg/core"
+)
+
+func Hset(args []string, getShard func(k string) *core.Shard) interface{} {
+	if (len(args)-2)%2 != 0 {
+		return errors.New("wrong number of arguments for 'HSET'")
+	}
+	key := args[1]
+	s := getShard(key)
+	item, exists := s.Data[key]
+	var hash map[string]string
+	if exists {
+		var ok bool
+		hash, ok = item.Value.(map[string]string)
+		if !ok {
+			return errors.New("WRONGTYPE Operation against a key holding the wrong kind of value")
+		}
+	} else {
+		hash = make(map[string]string)
+	}
+	count := 0
+	for i := 2; i < len(args); i += 2 {
+		hash[args[i]] = args[i+1]
+		count++
+	}
+	s.Data[key] = core.Item{Value: hash}
+	return count
+}
diff --git a/pkg/commands/hvalues.go b/pkg/commands/hvalues.go
new file mode 100644
index 0000000..1034fbd
--- /dev/null
+++ b/pkg/commands/hvalues.go
@@ -0,0 +1,24 @@
+package commands
+
+import (
+	"errors"
+	"redisClone/pkg/core"
+)
+
+func Hvalues(args []string, getShard func(k string) *core.Shard) interface{} {
+	key := args[1]
+	s := getShard(key)
+	item, exists := s.Data[key]
+	if !exists {
+		return nil
+	}
+	hash, ok := item.Value.(map[string]string)
+	if !ok {
+		return errors.New("WRONGTYPE Operation against a key holding the wrong kind of value")
+	}
+	values := make([]string, 0, len(hash))
+	for _, v := range hash {
+		values = append(values, v)
+	}
+	return values
+}
diff --git a/pkg/commands/keys.go b/pkg/commands/keys.go
new file mode 100644
index 0000000..b233964
--- /dev/null
+++ b/pkg/commands/keys.go
@@ -0,0 +1,41 @@
+package commands
+
+import (
+	"errors"
+	"path/filepath"
+	"redisClone/pkg/core"
+	"sort"
+	"strconv"
+)
+
+func Keys(args []string, getShard func(k string) *core.Shard) interface{} {
+	pattern := args[1]
+	limit := -1
+	if len(args) == 3 {
+		val, err := strconv.Atoi(args[2])
+		if err != nil {
+			return errors.New("value is not an integer")
+		}
+		limit = val
+	}
+
+	return dbInstance.ExecuteReadAll(func(shards []*core.Shard) interface{} {
+		var matches []string
+		for _, shard := range shards {
+			for key := range shard.Data {
+				matched, err := filepath.Match(pattern, key)
+				if err != nil {
+					return errors.New("illegal glob pattern")
+				}
+				if matched {
+					matches = append(matches, key)
+				}
+			}
+		}
+		sort.Strings(matches)
+		if limit != -1 && len(matches) > limit {
+			matches = matches[:limit]
+		}
+		return matches
+	})
+}
diff --git a/pkg/commands/lrem.go b/pkg/commands/lrem.go
new file mode 100644
index 0000000..38be270
--- /dev/null
+++ b/pkg/commands/lrem.go
@@ -0,0 +1,75 @@
+package commands
+
+import (
+	"errors"
+	"redisClone/pkg/core"
+	"strconv"
+)
+
+func Lrem(args []string, getShard func(k string) *core.Shard) interface{} {
+	key := args[1]
+	count, err := strconv.Atoi(args[2])
+	toBeRemoved := args[3]
+	if err != nil {
+		return errors.New("value is not an integer")
+	}
+
+	s := getShard(key)
+	item, exists := s.Data[key]
+	if !exists {
+		return 0
+	}
+	list, ok := item.Value.([]string)
+	if !ok {
+		return errors.New("WRONGTYPE Operation against a key holding the wrong kind of value")
+	}
+
+	counter := 0
+	absCount := count
+	if count < 0 {
+		absCount = -count
+	}
+
+	var newList []string
+	if count == 0 {
+		newList = []string{}
+		for _, value := range list {
+			if value == toBeRemoved {
+				counter++
+			} else {
+				newList = append(newList, value)
+			}
+		}
+	} else if count > 0 {
+		newList = []string{}
+		for _, value := range list {
+			if value == toBeRemoved && counter < absCount {
+				counter++
+			} else {
+				newList = append(newList, value)
+			}
+		}
+	} else { // count < 0
+		reversedNewList := []string{}
+		for i := len(list) - 1; i >= 0; i-- {
+			value := list[i]
+			if value == toBeRemoved && counter < absCount {
+				counter++
+			} else {
+				reversedNewList = append(reversedNewList, value)
+			}
+		}
+		newList = make([]string, len(reversedNewList))
+		for i, v := range reversedNewList {
+			newList[len(reversedNewList)-1-i] = v
+		}
+	}
+
+	if len(newList) == 0 {
+		delete(s.Data, key)
+	} else {
+		item.Value = newList
+		s.Data[key] = item
+	}
+	return counter
+}
diff --git a/pkg/commands/ping.go b/pkg/commands/ping.go
new file mode 100644
index 0000000..b56cd20
--- /dev/null
+++ b/pkg/commands/ping.go
@@ -0,0 +1,16 @@
+package commands
+
+import (
+	"errors"
+	"redisClone/pkg/core"
+)
+
+func Ping(args []string, getShard func(k string) *core.Shard) interface{} {
+	if len(args) == 1 {
+		return core.SimpleString("PONG")
+	}
+	if len(args) == 2 {
+		return args[1]
+	}
+	return errors.New("wrong number of arguments for 'PING' command")
+}
diff --git a/pkg/commands/type.go b/pkg/commands/type.go
new file mode 100644
index 0000000..2a7ef95
--- /dev/null
+++ b/pkg/commands/type.go
@@ -0,0 +1,24 @@
+package commands
+
+import (
+	"redisClone/pkg/core"
+)
+
+func Type(args []string, getShard func(k string) *core.Shard) interface{} {
+	key := args[1]
+	s := getShard(key)
+	item, exists := s.Data[key]
+	if !exists {
+		return core.SimpleString("none")
+	}
+	switch item.Value.(type) {
+	case string:
+		return core.SimpleString("string")
+	case []string:
+		return core.SimpleString("list")
+	case map[string]string:
+		return core.SimpleString("hash")
+	default:
+		return core.SimpleString("unknown")
+	}
+}