Unable to retrieve custom metadata from tables in rust

[universalmind303]

Environment

Delta-rs version:

Binding:

Environment:

• Cloud provider:
• OS:
• Other:

---

Bug

What happened:
AFAIK, there is no programmatic access to custom metadata written.

use std::sync::Arc;
use deltalake::{
    kernel::DataType as DeltaDataType,
    kernel::PrimitiveType,
    logstore::default_logstore, operations::create::CreateBuilder, protocol::SaveMode, storage::object_store::local::LocalFileSystem
};

use serde_json::json;
use url::Url;
#[tokio::main]
async fn main() {
    let path = tempfile::tempdir().unwrap();
    let path = path.into_path();
    
    let file_store = LocalFileSystem::new_with_prefix(path.clone()).unwrap();
    let log_store = default_logstore(
        Arc::new(file_store),
        &Url::from_file_path(path.clone()).unwrap(),
        &Default::default(),
    );

    let tbl = CreateBuilder::new()
        .with_log_store(log_store.clone())
        .with_save_mode(SaveMode::Overwrite)
        .with_metadata(vec![("my_custom_metadata".to_string(), json!({"key": "value"}))])
        .with_table_name("test")
        .with_column(
            "id",
            DeltaDataType::Primitive(PrimitiveType::Integer),
            true,
            None,
        );
    let tbl = tbl.await.unwrap();
    // how to get the metadata out of `tbl`?
}

How to get the metadata out of tbl?
DeltaTable.config does not have the app_metadata
DeltaTable.state.unwrap() does not have the app_metadata
DeltaTable::metadata() does not have the app_metadata

What you expected to happen:
Some way to retrieve the metadata
How to reproduce it:
See above
More details:
I can manually inspect the json file & it is getting written, but I have no way to retrieve it after it's been written.

[abhiaagarwal]

take

[abhiaagarwal]

After a bit of research, I think what you're looking for is DeltaTable::history()? It returns a Vec<CommitInfo>, which has the underlying metadata associated.

[ion-elgreco]

As @abhiaagarwal mentioned you need to fetch the commitInfo from history, also app metadata afaik is not preserved after checkpointing