Uuid query bind & result try_into invalid about stargate-grpc-rust-client HOT 7 CLOSED

@pkolaczk do you know what might be the cause? I was able to reproduce by trying to use (and slightly adapt to be precise) the uuid example code. I can share a gist if helpful.

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Can you show me your Cargo.toml and the command line you're building and running the program?
Feature uuid must be enabled explicitly to allow conversions to/from uuid::Uuid.
It is not sufficient to only add the uuid dependency.

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uuid = { version = "0.8.2", features = ["serde","v4"] }
stargate-grpc = {version = "0.3.0", features = ["uuid","macros","chrono"]}
stargate-grpc-derive = "0.2.0"

I didn't notice this at first, and it did help with conversion to cql, but the reverse still fails.

I should note, it may be helpful to expand the documentation a bit to more explicitly call this out, as with other cases like udt attributes IntoValue/TryFromValue, and how to handle sharing the mutable client. I'm fairly new to rust, maybe it's just me, but it would go a long way for my project.

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ok, so after adding the "uuid" feature, can you paste the actual code that's causing the problem?

let userid: Uuid = userid_res.rows.first().try_into()?;

That doesn't look right IMHO, because you're trying to convert the whole Row into a single Uuid.
You probably wanted to convert a column value to a Uuid.
Have you tried:

let userid: Uuid = userid_res.rows.first().try_take(0)?;

I should note, it may be helpful to expand the documentation a bit to more explicitly call this out, as with other cases like udt attributes IntoValue/TryFromValue

The docs contain a paragraph on exactly that. Is there anything missing there?

https://docs.rs/stargate-grpc/0.3.0/stargate_grpc/#working-with-uuids

and how to handle sharing the mutable client

Don't share. Simply create multiple clients. They are very lightweight.

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That doesn't look right IMHO, because you're trying to convert the whole Row into a single Uuid. You probably wanted to convert a column value to a Uuid. Have you tried:

let userid: Uuid = userid_res.rows.first().try_take(0)?;

rows.first() returns option, so I think it would have to be something closer to:
let userid_res: ResultSet = session.execute_query(userid_query).await?.try_into()?; let userid: Uuid; if let Some(row) = userid_res.rows.first() { userid = row.try_take(0).try_into()?; };

but this doesn't work either.

I should note, it may be helpful to expand the documentation a bit to more explicitly call this out, as with other cases like udt attributes IntoValue/TryFromValue

The docs contain a paragraph on exactly that. Is there anything missing there?

Only that I can't get it to work based on the docs. :/

Don't share. Simply create multiple clients. They are very lightweight.

One of the big advantages of Http/2 is that it allows multiple requests over the same connection, reducing connection overhead and boosting perf. Even Http/1.1 allows connection sharing, though with some limits. This advantage is lost if you have to open a connection for every request. For this use case, we can assume a high volume of concurrent requests. Protobuf gives us a bit of an edge, but I need to share connections. Unless I overlooked something?

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but this doesn't work either.

Then please provide the error message.

Only that I can't get it to work based on the docs. :/

All examples in the docs are fully compiled and tested automatically.
Also there is examples folder, and as far as I remember, one of the examples shows how to use uuids.
Have you tried looking there?

One of the big advantages of Http/2 is that it allows multiple requests over the same connection

Sure, but I didn't write you should create multiple connections, but just create multiple clients.
Cloning the clients is cheap and doesn't create more connections:

Tonic docs say:

/// `Channel` provides a
/// `Clone` implementation that is _cheap_. This is because at the very top level
/// the channel is backed by a `tower_buffer::Buffer` which runs the connection
/// in a background task and provides a `mpsc` channel interface. Due to this
/// cloning the `Channel` type is cheap and encouraged.

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In just released 0.4.0, you can try:

let row = userid_res.rows.first().unwrap();
let (userid,): (Uuid,) = row.try_into()?;

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