Preserve pathname prefix in re uri

[stefanwagnerdev]

Related

• Closes Preserve pathname prefix in re_uri #10373

What

This PR implements support for parsing proxy endpoints with arbitrary pathname prefixes in the RedapUri parser, addressing the issue where URLs like rerun+http://host/prefix/proxy would fail to parse

[jprochazk]

Hi, thanks for trying to address this! Overall, this needs some more work.

We've got many places in the code that are currently using re_uri::Origin directly instead of a full ProxyUri. That means they wouldn't handle path prefixes correctly. We should instead change Origin to handle path prefixes.

We also need to make sure that we reserve all paths which don't end in one of our endpoints, that way we can continue to add them in the future. For example, rerun+http://127.0.0.1:9876/rerun/something should be rejected completely, as neither rerun/something nor something is a valid endpoint.

Lastly, we'll need some updated docs. We need to be clear about:

• Endpoint paths may contain an arbitrary amount of prefix path segments
• We reserve the right to add other endpoints in the future, and will reject anything that isn't currently a valid endpoint.

This makes me think we should also preserve query params which we aren't using... 🤔 But you don't need to worry about that, it can be addressed another time.

Again, thanks for taking the time to look at this!

[jprochazk]

This general approach is sound, but it should apply to all endpoints, not just /proxy. One possible solution is to check the last N segments where N is the length of the endpoint, including any possible dynamic path segments.

For example, for /proxy we just need to check the last path segment. But for /dataset/{dataset_id}, we need to check the last 2.

[stefanwagnerdev]

It now handles the other endpoints as well

[jprochazk]

This still won't work as-is. If I add a log to tell me the actual HTTP URL which the gRPC client will attempt to connect to, and I run pixi run rerun --connect rerun+http://localhost/test/proxy, I get:

[2025-06-30T13:58:27Z DEBUG re_grpc_client::message_proxy::read] Loading rerun+http://localhost:9876/test/proxy via gRPC…
[2025-06-30T13:58:27Z INFO  re_grpc_client::message_proxy::read] actual URL: http://localhost:9876

Which is missing the path prefix. This needs to go through re_uri::Origin, not the endpoint struct. Here's a test that should pass if path segments are properly supported:

#[test]
fn resolved_endpoints_with_prefix() {
    let cases = [
        // HTTP
        (
            "rerun+http://localhost/a/b/proxy",
            "http://localhost:9876/a/b",
        ),
        (
            "rerun+http://localhost/a/b/catalog",
            "http://localhost:51234/a/b",
        ),
        (
            "rerun+http://localhost/a/b/entry/1830B33B45B963E7774455beb91701ae",
            "http://localhost:51234/a/b",
        ),
        (
            "rerun+http://localhost/a/b/dataset/1830B33B45B963E7774455beb91701ae/data?partition_id=pid",
            "http://localhost:51234/a/b",
        ),
        // HTTPS
        (
            "rerun://example.com/foo/bar/proxy",
            "https://example.com:443/foo/bar",
        ),
        (
            "rerun://example.com/foo/bar/catalog",
            "https://example.com:443/foo/bar",
        ),
        (
            "rerun://example.com/foo/bar/entry/1830B33B45B963E7774455beb91701ae",
            "https://example.com:443/foo/bar",
        ),
        (
            "rerun://example.com/foo/bar/dataset/1830B33B45B963E7774455beb91701ae/data?partition_id=pid",
            "https://example.com:443/foo/bar",
        ),
    ];

    for (url, expected) in cases {
        let result: RedapUri = url.parse().expect("failed to parse proxy URL");
        assert_eq!(
            expected,
            result.origin().as_url(),
            "failed to resolve {url}"
        );
    }
}

[jprochazk]

It's also important that you actually test this for your own use case, a locally-running rerun --serve-web behind an nginx proxy which you attempt to connect to in a web browser.

[Wumpf]

looks abandoned. Closing for book-keeping purposes. Please re-open if there's new movement here