Unable To GET values from the replica

Challenges
1

I’m stuck on Stage Challenges #YG4.

I am unable to understand why i am not able to get value in the replica even though i have sent the set request to it.

Here are my logs:

[tester::#YG4] [handshake] Received ["PSYNC", "?", "-1"]
[tester::#YG4] [handshake] master: Sent "FULLRESYNC 75cd7bc10c49047e0d163660f3b90625b1af31dc 0"
[tester::#YG4] [handshake] master: Sent bytes: "+FULLRESYNC 75cd7bc10c49047e0d163660f3b90625b1af31dc 0\r\n"
[tester::#YG4] [handshake] Sending RDB file...
[tester::#YG4] [handshake] master: Sent bytes: "$88\r\nREDIS0011\xfa\tredis-ver\x057.2.0\xfa\nredis-bits\xc0@\xfa\x05ctime\xc2m\b\xbce\xfa\bused-mem°\xc4\x10\x00\xfa\baof-base\xc0\x00\xff\xf0n;\xfe\xc0\xffZ\xa2"
[tester::#YG4] [handshake] Sent RDB file.
[tester::#YG4] [propagation] master: > SET foo 123
[tester::#YG4] [propagation] master: Sent bytes: "*3\r\n$3\r\nSET\r\n$3\r\nfoo\r\n$3\r\n123\r\n"
[tester::#YG4] [propagation] master: > SET bar 456
[tester::#YG4] [propagation] master: Sent bytes: "*3\r\n$3\r\nSET\r\n$3\r\nbar\r\n$3\r\n456\r\n"
[tester::#YG4] [propagation] master: > SET baz 789
[tester::#YG4] [propagation] master: Sent bytes: "*3\r\n$3\r\nSET\r\n$3\r\nbaz\r\n$3\r\n789\r\n"
[tester::#YG4] [test] Getting key foo
[tester::#YG4] [test] client: $ redis-cli GET foo
[tester::#YG4] [test] client: Sent bytes: "*2\r\n$3\r\nGET\r\n$3\r\nfoo\r\n"
[tester::#YG4] [test] client: Received bytes: "$-1\r\n"
[tester::#YG4] [test] client: Received RESP null bulk string: "$-1\r\n"
[your_program] Processing GET operation with following args [{Value:foo IsNull:false}]
[tester::#YG4] [test] Retrying... (1/5 attempts)
[tester::#YG4] [test] client: > GET foo
[tester::#YG4] [test] client: Sent bytes: "*2\r\n$3\r\nGET\r\n$3\r\nfoo\r\n"
[tester::#YG4] [test] client: Received bytes: "$-1\r\n"
[tester::#YG4] [test] client: Received RESP null bulk string: "$-1\r\n"
[tester::#YG4] [test] Retrying... (2/5 attempts)
[tester::#YG4] [test] client: > GET foo
[tester::#YG4] [test] client: Sent bytes: "*2\r\n$3\r\nGET\r\n$3\r\nfoo\r\n"
[your_program] Processing GET operation with following args [{Value:foo IsNull:false}]
[tester::#YG4] [test] client: Received bytes: "$-1\r\n"
[tester::#YG4] [test] client: Received RESP null bulk string: "$-1\r\n"
[your_program] Processing GET operation with following args [{Value:foo IsNull:false}]
[tester::#YG4] [test] Retrying... (3/5 attempts)
[tester::#YG4] [test] client: > GET foo
[tester::#YG4] [test] client: Sent bytes: "*2\r\n$3\r\nGET\r\n$3\r\nfoo\r\n"
[tester::#YG4] [test] client: Received bytes: "$-1\r\n"
[tester::#YG4] [test] client: Received RESP null bulk string: "$-1\r\n"
[your_program] Processing GET operation with following args [{Value:foo IsNull:false}]
[tester::#YG4] [test] Retrying... (4/5 attempts)
[tester::#YG4] [test] client: > GET foo
[tester::#YG4] [test] client: Sent bytes: "*2\r\n$3\r\nGET\r\n$3\r\nfoo\r\n"
[tester::#YG4] [test] client: Received bytes: "$-1\r\n"
[tester::#YG4] [test] client: Received RESP null bulk string: "$-1\r\n"
[your_program] Processing GET operation with following args [{Value:foo IsNull:false}]
[tester::#YG4] [test] Retrying... (5/5 attempts)
[tester::#YG4] [test] client: > GET foo
[tester::#YG4] [test] client: Sent bytes: "*2\r\n$3\r\nGET\r\n$3\r\nfoo\r\n"
[tester::#YG4] [test] client: Received bytes: "$-1\r\n"
[tester::#YG4] [test] client: Received RESP null bulk string: "$-1\r\n"
[your_program] Processing GET operation with following args [{Value:foo IsNull:false}]
[tester::#YG4] Expected simple string or bulk string, got NIL

And here’s a snippet of my code:

	replicaConn := tools.GetReplicaConns()
	if len(replicaConn) > 0 {
		for _, conn := range replicaConn {
			serverhelpers.SendSetCommandToReplica(conn, key.Value, value.Value)
		}
	}

func SendSetCommandToReplica(conn net.Conn, key string, val string) {
	sendSetCommand := fmt.Sprintf("*3%s%s%s%s",
		tools.CLRF,
		tools.RedisBulkString("SET").Encode(),
		tools.RedisBulkString(key).Encode(),
		tools.RedisBulkString(val).Encode(),
	)
	conn.Write([]byte(sendSetCommand))
}
2

@skadoodle1201 can you try adding logs in your code around the relevant areas? (more on this here: How do I debug test failures? - CodeCrafters)

I see the tester logs above, but what’d be more useful is to know whether your code is triggering when commands are propagated to it.

3

Hey @rohitpaulk i am not sure where to put logs cause in master i can see the SET command being parse properly but when i send that command to the replica i am not sure whats happening cause logs are not getting printed i have debug mode as true still no logs

[tester::#YG4] [test] client: Sent bytes: "*2\r\n$3\r\nGET\r\n$3\r\nfoo\r\n"
[tester::#YG4] [test] client: Received bytes: "$-1\r\n"
[tester::#YG4] [test] client: Received RESP null bulk string: "$-1\r\n"
[your_program] Processing GET operation with following args [{Value:foo IsNull:false}]
[tester::#YG4] Expected simple string or bulk string, got NIL
[tester::#YG4] Test failed
5

Closing this thread due to inactivity. If you still need assistance, feel free to start a new discussion!

6

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