Storage: read_object fails when object content-encoding is gzip

[renato145]

Environment details

• Programming language: rust
• OS: ubuntu 22.04
• Language runtime version: 1.90
• Package version: 1.1.0

Steps to reproduce

1. Following the example code to download an object:

storage
        .read_object("projects/_/buckets/xxx", "some-file.tar.gz")
        .send()
        .await;

I get the following error when the file have "gzip" as the Content-Encoding value in its metadata:

cannot deserialize the response the response is missing 'content-length', a required header
--------------------
Error {
    kind: Deserialization,
    source: Some(
        MissingHeader(
            "content-length",
        ),
    ),
}

When Content-Encoding is not present, there is no error. I tested by editing the metadata in https://console.cloud.google.com/storage/browser/

[coryan]

This is easy enough to repro (I did in my branch). The problem is in the code to resume downloads, it assumes the `content-length' header is always there. I forgot (or neglected to check) that the header is missing when reading gunzipped objects. It also does not matter, it is not possible to resume uploads during downloads either.

We should ignore the header for gunzipped objects and also stop trying to resume such downloads.