feat(services/ftp): Setup integration tests

[Xuanwo]

Signed-off-by: Xuanwo [email protected]

I hereby agree to the terms of the CLA available at: https://databend.rs/dev/policies/cla/

Summary

Fix #626

[Xuanwo]

Hi, @ArberSephirotheca

I have set up integration tests in this PR in action Service Test Ftp. Can you take a look at the failed tests?

Since you have been granted the write permission for this project, you can use gh pr checkout 648 and push to this branch directly for testing.

[Xuanwo]

thread 'services_ftp_list::test_check' panicked at 'mode DIR not match with path a5386fcf-3f1f-424d-ac9d-f6b80fbb43fa', src/dir.rs:61:9

OpenDAL requires all dir must end with /. We can append a / to the path while returning a Dir entry.

[ArberSephirotheca]

Also maybe we need Mutex for client field(to extend its lifetime to 'static and to provide internal mutability)? Because we are passing client field to fut, and we need it to be mutable(read_response_in() and quit() functions inside fut all require &mut self).

In my previous code, I cannot directly pass self.client to fut due to lifetime problem(&mut Self cannot live long). So I first clone the Arc pointer to client field before fut, then I do Arc::get_mut() inside fut. However, Arc::get_mut() only works if there are no other Arc pointers to the same allocation, but we got 2 references here.

[Xuanwo]

In my previous code, I cannot directly pass self.client to fut due to lifetime problem(&mut Self cannot live long). So I first clone the Arc pointer to client field before fut, then I do Arc::get_mut() inside fut. However, Arc::get_mut() only works if there are no other Arc pointers to the same allocation, but we got 2 references here.

I got it. I think we don't need Arc<FtpStream> here. To access a &mut FtpStream, we can put Option<FtpStream> in State directly. While building the future, we can move it into future directly like the following:

pub enum State {
    Reading(Option<FtpStream>),
    Finalize(BoxFuture<'static, Result<()>>),
}

let ft = ft.replace(None);
let fut = async move {
    ft.read_response_in()
    xxxx
}
state = Box::pin(fut);

For example, you can take a look at:

https://github.com/datafuselabs/opendal/blob/5595a0ec611dd1a666dda1ce34b23c20a989321d/src/services/ipfs/backend.rs#L523-L524

[ArberSephirotheca]

All failures are sovled execpt one about stat operation. As there is no command in FTP that get information of single file/directory, I use list command for stat operation. list command works fine if we want information of a single file(it just return a vector of size 1). However, it does not work if we want to get information of a directory. For example, If we want to get metadata of a directory throwawayaa/ it self, the listcommand would try to get metada of any files or subdirectory within that directory rather than itself.
We could solve it by first list its parent directory and then find the information of directory we want from vector of results, but what if user want the metadata of /(root directory)?

[Xuanwo]

We can always return ObjectMode::DIR for root dir. Other metadata can leave as empty.

[Xuanwo]

Thanks for your hard-working! We can release FTP support for the next release now!