Writing data to another shard in gears function reports "gears.error: Operation not permitted"

[songweijia]

I created a very simple RedisGears function as follows.

def failed_function(x):
    execute('SET', 'A', 'SOMEVALUE')
    
GearsBuilder('KeysReader').foreach(failed_function).run('a')

I created an entry by 'SET a somevalue' in a cluster composed of three shards, then ran the function. It reported 'Operation not permitted.'

$ cat debug.py | redis-cli -c -p 7000 -x rg.pyexe
cute
1) (empty array)
2) 1) "['Traceback (most recent call last):\\n', '  File \"<string>\", line 2, in failed_function\\n', 'gears.error: Operation not permitted\\n']"

But If I just change one byte of the code: 'A'->'a', then run it in the same environment. It works fine.

def ok_function(x):
    execute('SET', 'a', 'SOMEVALUE')
    
GearsBuilder('KeysReader').foreach(failed_function).run('a')

Obviously, the issue is about the sharding: Key 'A' and 'a' are in different shards. It turns out that if I write the data in another shard, this operation is not permitted.

127.0.0.1:7000> get 'a'
-> Redirected to slot [15495] located at 127.0.0.1:7002
"SOMEVALUE"
127.0.0.1:7002> get 'A'
-> Redirected to slot [6373] located at 127.0.0.1:7001

Is this the design of RedisGears or did I miss anything?

---

More information:

• I'm using the docker image "redislabs/redisgears:latest"
• I planned to try "redislabs/redisgears:2.0.19-m20". But I haven't found the API document of RedisGear2. So I didn't do it.
• cluster information:

127.0.0.1:7001> RG.INFOCLUSTER
1) "MyId"
2) "4cd5dbe8debbddc23764e65e35dade5f46774d37"
3) "MyRunId"
4) "afcb8bbc6bbc4ada6a36ca3a6f936a8216051d4f"
5) 1)  1) "id"
       2) "949dc5f01a31d64ada4e8eb5c2ca024b1f408512"
       3) "ip"
       4) "127.0.0.1"
       5) "port"
       6) (integer) 7002
       7) "unixSocket"
       8) "None"
       9) "runid"
      10) "994f068609a1a75220b945590ff64b8668f8ae3f"
      11) "minHslot"
      12) (integer) 10923
      13) "maxHslot"
      14) (integer) 16383
      15) "pendingMessages"
      16) (integer) 0
   2)  1) "id"
       2) "4cd5dbe8debbddc23764e65e35dade5f46774d37"
       3) "ip"
       4) "127.0.0.1"
       5) "port"
       6) (integer) 7001
       7) "unixSocket"
       8) "None"
       9) "runid"
      10) "afcb8bbc6bbc4ada6a36ca3a6f936a8216051d4f"
      11) "minHslot"
      12) (integer) 5461
      13) "maxHslot"
      14) (integer) 10922
      15) "pendingMessages"
      16) (integer) 0
   3)  1) "id"
       2) "ec6b13c723a2ee1b1e1ee682e2d070b9a0a1f1c4"
       3) "ip"
       4) "127.0.0.1"
       5) "port"
       6) (integer) 7000
       7) "unixSocket"
       8) "None"
       9) "runid"
      10) "bea227c3cf4edf80adebec764e41d93cd4f69cc8"
      11) "minHslot"
      12) (integer) 0
      13) "maxHslot"
      14) (integer) 5460
      15) "pendingMessages"
      16) (integer) 0