Implemented LSET command

server/plugins/commands/list/list.go

@@ -53,6 +53,9 @@ func (p *plugin) HandleCommand(cmd []string, server interface{}, conn *bufio.Wri
 	case c == "lrange":
 		handleLRange(cmd, server.(Server), conn)
 
+	case c == "lset":
+		handleLSet(cmd, server.(Server), conn)
+
 	case utils.Contains[string]([]string{"lpush", "lpushx"}, c):
 		handleLPush(cmd, server.(Server), conn)
 
@@ -211,6 +214,48 @@ func handleLRange(cmd []string, server Server, conn *bufio.Writer) {
 	conn.Flush()
 }
 
+func handleLSet(cmd []string, server Server, conn *bufio.Writer) {
+	if len(cmd) != 4 {
+		conn.Write([]byte("-Error wrong number of arguments for LSET command\r\n\n"))
+		conn.Flush()
+		return
+	}
+
+	server.Lock()
+
+	list, ok := server.GetData(cmd[1]).([]interface{})
+
+	if !ok {
+		server.Unlock()
+		conn.Write([]byte("-Error LSET command on non-list item\r\n\n"))
+		conn.Flush()
+		return
+	}
+
+	index, ok := utils.AdaptType(cmd[2]).(int)
+
+	if !ok {
+		server.Unlock()
+		conn.Write([]byte("-Error index must be an integer\r\n\n"))
+		conn.Flush()
+		return
+	}
+
+	if !(index >= 0 && index < len(list)) {
+		server.Unlock()
+		conn.Write([]byte("-Error index must be within range\r\n\n"))
+		conn.Flush()
+		return
+	}
+
+	list[index] = utils.AdaptType(cmd[3])
+	server.SetData(cmd[1], list)
+	server.Unlock()
+
+	conn.Write([]byte(OK))
+	conn.Flush()
+}
+
 func handleLPush(cmd []string, server Server, conn *bufio.Writer) {
 	if len(cmd) < 3 {
 		conn.Write([]byte(fmt.Sprintf("-Error wrong number of arguments for %s command\r\n\n", strings.ToUpper(cmd[0]))))
@@ -345,17 +390,16 @@ func init() {
 		"lpop",   // (LPOP key) Removes and returns the first element of a list.
 		"llen",   // (LLEN key) Return the length of a list.
 		"lrange", // (LRANGE key start end) Return a range of elements between the given indices.
-		"lmove",     // (LMOVE key1 key2 LEFT/RIGHT LEFT/RIGHT) Move element from one list to the other specifying left/right for both lists.
+		"lindex", // (LINDEX key index) Gets list element by index.
-		"lrem",      // (LREM key count value) Remove elements from list.
 		"lset",   // (LSET key index value) Sets the value of an element in a list by its index.
 		"ltrim",  // (LTRIM key start end) Trims a list to the specified range.
-		"lincr",     // (LINCR key index) Increment the list element at the given index by 1.
+		"lrem",   // (LREM key count value) Remove elements from list.
-		"lincrby",   // (LINCRBY key index value) Increment the list element at the given index by the given value.
+		"lmove",  // (LMOVE key1 key2 LEFT/RIGHT LEFT/RIGHT) Move element from one list to the other specifying left/right for both lists.
-		"lindex",    // (LINDEX key index) Gets list element by index.
+
 		"rpop",      // (RPOP key) Removes and gets the last element in a list.
-		"rpoplpush", // (RPOPLPUSH key1 key2) Removes last element of one list, prepends it to another list and returns it.
 		"rpush",     // (RPUSH key value [value2]) Appends one or multiple elements to the end of a list.
 		"rpushx",    // (RPUSHX key value) Appends an element to the end of a list, only if the list exists.
+		"rpoplpush", // (RPOPLPUSH key1 key2) Removes last element of one list, prepends it to another list and returns it.
 	}
 	Plugin.description = "Handle List commands"
 }

utils/utils.go

@@ -4,11 +4,13 @@ import (
 	"bufio"
 	"bytes"
 	"encoding/json"
+	"errors"
 	"flag"
 	"fmt"
 	"math"
 	"os"
 	"path"
+	"reflect"
 	"strconv"
 
 	"gopkg.in/yaml.v3"
@@ -111,6 +113,25 @@ func AdaptType(s string) interface{} {
 	return n
 }
 
+func IncrBy(num interface{}, by interface{}) (interface{}, error) {
+	if !Contains[string]([]string{"int", "float64"}, reflect.TypeOf(num).String()) {
+		return nil, errors.New("can only increment number")
+	}
+	if !Contains[string]([]string{"int", "float64"}, reflect.TypeOf(by).String()) {
+		return nil, errors.New("can only increment by number")
+	}
+
+	n, _ := num.(float64)
+	b, _ := by.(float64)
+	res := n + b
+
+	if IsInteger(res) {
+		return int(res), nil
+	}
+
+	return res, nil
+}
+
 func ReadMessage(r *bufio.ReadWriter) (message string, err error) {
 	var line [][]byte