list_with_depth

List objects from [object_store] with the given prefix and depth, and an implementation specific delimiter. Returns common prefixes (directories) in addition to object metadata.

For example, say that a bucket contains the following objects:

• a.txt
• foo/b.txt
• foo/bar/c.txt
• foo/bar/d.txt

Calling [list_with_depth] with depth = 0 is equivalent to calling [ObjectStore::list_with_delimiter]: It will return the objects and common prefixes at the root: objects=["a.txt"] and common_prefixes=["foo"].

Calling [list_with_depth] with depth = 1 will recurse once, and return objects=["foo/b.txt"] and common_prefixes=["foo/bar"].

The equivalent commands at a Unix command line would be:

• ls * (depth=0)
• ls */* (depth=1)
• ls */*/* (depth=2)
• etc.

Prefixes are evaluated on a path segment basis, i.e. foo/bar is a prefix of foo/bar/x but not of foo/bar_baz/x.

Example

use std::sync::Arc;
use list_with_depth::list_with_depth;
use object_store::{memory::InMemory, PutPayload, ObjectStore, ListResult, path::Path};

#[tokio::main(flavor = "current_thread")]
async fn main() -> object_store::Result<()> {

    // Create some objects in memory:
    const KEYS: [&str; 4] = [
        "a.txt",
        "foo/b.txt",
        "foo/bar/c.txt",
        "foo/bar/d.txt",
    ];
    let store = Arc::new(InMemory::new());
    for key in KEYS {
        store.put(&key.into(), PutPayload::new()).await?;
    }

    // Call `list_with_depth` with `depth = 0`:
    let depth = 0;
    let prefix = None;
    let ListResult{
        objects, 
        common_prefixes
    } = list_with_depth(store.clone(), prefix, depth).await?;
    assert_eq!(objects[0].location, Path::from("a.txt"));
    assert_eq!(common_prefixes, vec![Path::from("foo")]);

    // Call `list_with_depth` with `depth = 1`:
    let depth = 1;
    let prefix = None;
    let ListResult{
        objects, 
        common_prefixes
    } = list_with_depth(store.clone(), prefix, depth).await?;
    assert_eq!(objects[0].location, Path::from("foo/b.txt"));
    assert_eq!(common_prefixes, vec![Path::from("foo/bar")]);

    Ok(())
}