refactor: isolate session_id and session states of diff users.

[youngsofun]

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Summary

By putting session id under user_name when used as a key.

• fixes: refactor: put client-session related objects under user_name #16565

Tests

• Unit Test
• Logic Test
• Benchmark Test
• No Test - Explain why

Type of change

• Bug Fix (non-breaking change which fixes an issue)
• New Feature (non-breaking change which adds functionality)
• Breaking Change (fix or feature that could cause existing functionality not to work as expected)
• Documentation Update
• Refactoring
• Performance Improvement
• Other (please describe):

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This change is 

[drmingdrmer]

Reviewed 1 of 11 files at r1, all commit messages.
Reviewable status: 1 of 11 files reviewed, 2 unresolved discussions (waiting on @youngsofun)

---

src/meta/app/src/principal/client_session_ident.rs line 75 at r1 (raw file):

        Self::parse(&s)
    }
}

There is no need to manually encode the session_id and user_name with a colon. Just treat them as two key segment:

Suggestion:

impl KeyCodec for UserSessionId {
    fn encode_key(&self, b: KeyBuilder) -> KeyBuilder {
        b.push_str(&self.session_id).push_str(&self.user_name)
    }

    fn decode_key(parser: &mut KeyParser) -> Result<Self, KeyError>
    where Self: Sized {
        let s = parser.next_str()?;
        let u = parser.next_str()?;
        Ok(Self{ session_id: s, user_name: u})
    }
}

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src/meta/protos/proto/client_session.proto line 26 at r1 (raw file):

  uint64 ver = 100;
  uint64 min_reader_ver = 101;
  string user_name = 2;

A removed field should be reserved to prevent further use with: https://protobuf.dev/programming-guides/proto3/#reserved

[youngsofun]

Just treat them as two key segment
good idea, thank you

A removed field should be reserved to prevent further use with: https://protobuf.dev/programming-guides/proto3/#reserved

this is not used in production for now, can I skip the step and delete it directly?

[drmingdrmer]

Just treat them as two key segment
good idea, thank you

A removed field should be reserved to prevent further use with: https://protobuf.dev/programming-guides/proto3/#reserved

this is not used in production for now, can I skip the step and delete it directly?

I'd suggest always following the rule if it doesn't create additional work.
Although it's unlikely to happen, there's still an odd that a binary with this field has been deployed somewhere we're unaware of. It's better to be cautious.

[youngsofun]

@drmingdrmer Your suggestions have all been adopted. please review again.

[drmingdrmer]

Reviewed 5 of 11 files at r1, 6 of 6 files at r2, all commit messages.
Reviewable status: all files reviewed, 2 unresolved discussions (waiting on @youngsofun)

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src/query/service/src/servers/http/v1/session/client_session_manager.rs line 111 at r2 (raw file):

    pub fn state_key(client_session_id: &str, user_name: &str) -> String {
        format!("{client_session_id}:{user_name}")

The client_session_id and user_name should be escaped to prevent any : characters within them from interfering with the key format.

And if this state_key is not used for transport, the return value can be just any Hash type, such as (client_session_id, user_name), which can be used as hash map key.

Code quote:

    pub fn state_key(client_session_id: &str, user_name: &str) -> String {
        format!("{client_session_id}:{user_name}")

[youngsofun]

@drmingdrmer you are right, I will refactor it to return simply (client_session_id, user_name) in next pr coming soon.