Feature: allow to pass the image URL directly to the devices (without proxying)

[b4u-mw]

My use case: I have the image on an external server along with related files (especially casync index directories). With proxying, 2 things happen:

1. the original URL that contains username+password gets lost
2. the casync dir which is resolved relative to the rauc bundle is not found

The change is simple, a PR follows.

[easybe]

This appears to be a regression introduced with commit b16bb2c which breaks the CDN use case.

Simply reverting the code in question

--- a/goosebit/updates/__init__.py
+++ b/goosebit/updates/__init__.py
@@ -98,9 +98,15 @@ async def generate_chunk(request: Request, device: Device) -> list[UpdateChunk]:
     if software is None:
         return []
 
-    # Always use the download endpoint for consistency, the endpoint
-    # will handle both local and remote files appropriately.
-    href = str(request.url_for("download_artifact", dev_id=device.id))
+    if software.local:
+        href = str(
+            request.url_for(
+                "download_artifact",
+                dev_id=device.id,
+            )
+        )
+    else:
+        href = software.uri
 
     return [
         UpdateChunk(

seems to break S3 support:

>           assert finished, (
                f"Device {dev_id} did not finish update to {target_version}. "
                f"initial={initial_version}, observed={observed_version}"
            )
E           AssertionError: Device 8dfcafec did not finish update to 1.0.0. initial=0.1.0, observed=0.1.0
E           assert False

tests/e2e/s3/tests/test_e2e_s3.py:217: AssertionError

[easybe]

I commented on the issue: #399 (comment). @jkuri are you around to help us out here?

I'll check later today, but as far as I recall I did fix the CDN issue later after this was introduced.

I guess you are right. I get redirected (307) to the external URL. Any thoughts on

1. the original URL that contains username+password gets lost
2. the casync dir which is resolved relative to the rauc bundle is not found

?

[easybe]

I understand the redirect is causing issues for RAUC. Can we avoid it for external URLs?

[b4u-mw]

Fixed by #400