How to use JSON.GET and JSON.SET commands?

[nightroman]

I am using the Garnet server, built locally, with the SERedis client. Commands like this fail with "ERR unknown command"

db.Execute("JSON.GET", "...")

Should I configure the server in some way to enable the JSON module?
Like to enable Lua, I need some settings. I cannot see anything about JSON.

I am using https://github.com/microsoft/garnet/releases/tag/v1.0.66 with this work included #974

[nightroman]

@Vijay-Nirmal as the author of that PR, do you have any insights?

[prvyk]

You should start Garnet with --loadmodulecs parameters pointed to GarnetJSON.dll module:

garnet-server --loadmodulecs fullpath/...GarnetJSON.dll

MODULE LOADCS command does the same thing. [Edit: MODULE LOADCS now requires enable-module-command to be set (--enable-module-command). Also ExtensionBinPaths (--extension-bin-path). ]

The GarnetJSON.dll module is apparently not included in the artefacts - you'll need to build it manually.

[prvyk]

Don't you need another argument?

JSON.SET zoo:1.json $ '{"name":"Bob"}'

https://redis.io/docs/latest/commands/json.set/

[nightroman]

ERROR: Exception calling "Execute" with "4" argument(s): "SocketClosed (ReadEndOfStream, last-recv: 0) on 127.0.0.1:3278/Interactive, Idle/MarkProcessed, last: ECHO
, origin: ReadFromPipe, outstanding: 2, last-read: 0s ago, last-write: 0s ago, keep-alive: 60s, state: ConnectedEstablished, mgr: 9 of 10 available, in: 0, in-pipe:
 0, out-pipe: 0, last-heartbeat: 0s ago, last-mbeat: 0s ago, global: 0s ago, v: 2.8.37.59676"
At ...
+     [string]$db.Execute('JSON.SET', 'zoo:1.json', '$', '{"name":"Bob" …
+     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

[prvyk]

Odd. It works from redis-cli ...

127.0.0.1:6379> JSON.SET zoo:1.json $ '{"name":"Bob"}'
OK
127.0.0.1:6379> JSON.GET zoo:1.json $.name
"[\"Bob\"]"

[nightroman]

from server log some more

08::50::48 info: Session[0] [127.0.0.1:55273] [01F9ED70] Module GarnetJSON version 1 loaded
08::50::53 crit: Session[0] [127.0.0.1:55273] [01F9ED70] ProcessMessages threw an exception: System.NullReferenceException: Object reference not set to an instance of an object.    at Garnet.server.ObjectSessionFunctions.InPlaceUpdaterWorker(Byte[]& key, ObjectInput& input, IGarnetObject& value, GarnetObjectStoreOutput& output, RMWInfo& rmwInfo, Int64& sizeChange) in /_/libs/server/Storage/Functions/ObjectStore/RMWMethods.cs:line 110    at Garnet.server.ObjectSessionFunctions.InPlaceUpdater(Byte[]& key, ObjectInput& input, IGarnetObject& value, GarnetObjectStoreOutput& output, RMWInfo& rmwInfo, RecordInfo& recordInfo) in /_/libs/server/Storage/Functions/ObjectStore/RMWMethods.cs:line 94    at Garnet.server.StorageSession.RMW_ObjectStore[TObjectContext](Byte[]& key, ObjectInput& input, GarnetObjectStoreOutput& output, TObjectContext& objectStoreContext) in /_/libs/server/Storage/Session/ObjectStore/AdvancedOps.cs:line 17    at Garnet.server.GarnetApi`2.RMW_ObjectStore(Byte[]& key, ObjectInput& input, GarnetObjectStoreOutput& output) in /_/libs/server/API/GarnetApi.cs:line 304    at Garnet.server.RespServerSession.TryCustomObjectCommand[TGarnetApi](GarnetObjectType objType, Byte subid, CommandType type, TGarnetApi& storageApi) in /_/libs/server/Custom/CustomRespCommands.cs:line 150    at Garnet.server.RespServerSession.NetworkCustomObjCmd[TGarnetApi](TGarnetApi& storageApi) in /_/libs/server/Resp/RespServerSession.cs:line 1045    at Garnet.server.RespServerSession.ProcessOtherCommands[TGarnetApi](RespCommand command, TGarnetApi& storageApi) in /_/libs/server/Resp/RespServerSession.cs:line 937    at Garnet.server.RespServerSession.ProcessArrayCommands[TGarnetApi](RespCommand cmd, TGarnetApi& storageApi) in /_/libs/server/Resp/RespServerSession.cs:line 895    at Garnet.server.RespServerSession.ProcessMessages() in /_/libs/server/Resp/RespServerSession.cs:line 556    at Garnet.server.RespServerSession.TryConsumeMessages(Byte* reqBuffer, Int32 bytesReceived) in /_/libs/server/Resp/RespServerSession.cs:line 405

[nightroman]

FWIW, how to repro maybe. I'm using this PowerShell module -- https://www.powershellgallery.com/packages/FarNet.Redis (I'm the author) and commands like these:

Import-Module FarNet.Redis
$db = Open-Redis 127.0.0.1:3278
	[string]$db.Execute('MODULE', 'LOADCS', 'C:\Bin\Garnet\GarnetJSON.dll')
OK
	[string]$db.Execute('JSON.SET', 'zoo:1.json', '$', '{"name":"Bob"}')
problem