413 Entity Too Large Error when publishing Debian Bullseye mirror to S3 (Ceph Object Storage) with large file sizes

Start by tracing Aptly's S3 publishing path and how it uploads large objects; the issue provides no source files or tests to begin from. Check whether the configured S3-compatible storage's multipart-upload size constraints can be accommodated, then add or run relevant upload tests. Done means publishing the reported 670 MB package succeeds against the stated storage limits.

I have a Debian Bullseye mirror that I want to publish to an S3-compatible storage (Ceph). However, I'm encountering an issue when trying to publish the mirror. The S3-compatible storage has a maximum size limit for a single part of 5GB and for multipart uploads, it's 500MB, with a minimum size for multipart uploads being 5MB. When I attempt to publish the mirror, I receive a "413 Request Entity Too Large" error.

Here's the error log:

 3 / 119009 [>-------------------------------------------------------------------]   0.00% 11h24m30s2023/05/10 09:40:17 DEBUG: Request s3/PutObject Details:
---[ REQUEST POST-SIGN ]-----------------------------
PUT /apt-mirror/debian/bullseye-test/pool/main/0/0ad-data/0ad-data_0.0.23.1-1.1_all.deb HTTP/1.1
Host: s3.ir-thr-at1.arvanstorage.ir
User-Agent: aws-sdk-go/1.25.0 (go1.17.11; linux; amd64)
Content-Length: 701833824
Authorization: AWS4-HMAC-SHA256 Credential=7cd89524-2748-4483-834a-d5dc48d85aaf/20230510/us-east-1/s3/aws4_request, SignedHeaders=content-length;content-md5;host;x-amz-acl;x-amz-content-sha256;x-amz-date;x-amz-meta-md5, Signature=xxxx
Content-Md5: srblUQiYq/Du552kiZX5Lw==
Expect: 100-Continue
X-Amz-Acl: private
X-Amz-Content-Sha256: afb3f0ddaceb36dc2d716d83d7fee4ada419511a948e4a06fa44bbc1b486e2c0
X-Amz-Date: 20230510T094009Z
X-Amz-Meta-Md5: b2b6e5510898abf0eee79da48995f92f
Accept-Encoding: gzip


-----------------------------------------------------
2023/05/10 09:40:17 DEBUG: Response s3/PutObject Details:
---[ RESPONSE ]--------------------------------------
HTTP/2.0 413 Request Entity Too Large
Content-Length: 189
Access-Control-Allow-Credentials: true
Access-Control-Allow-Headers: Authorization,Accept,Origin,DNT,X-CustomHeader,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Content-Range,Range
Access-Control-Allow-Methods: GET,POST,OPTIONS,PUT,DELETE,PATCH
Access-Control-Allow-Origin: *
Content-Type: text/html
Date: Wed, 10 May 2023 09:40:17 GMT
Server: ArvanCloud
Server-Timing: total;dur=50
X-Request-Id: 11011f780026e6a8710dbaf03756598d
X-Sid: 2063


-----------------------------------------------------
ERROR: unable to publish: unable to process packages: error uploading af/b3/f0ddaceb36dc2d716d83d7fee4ad_0ad-data_0.0.23.1-1.1_all.deb to S3: us-east-1:apt-mirror/: debian/bullseye-test/pool/main/0/0ad-data/0ad-data_0.0.23.1-1.1_all.deb: SerializationError: failed to unmarshal error message 
status code: 413, request id: , host id: 
caused by: UnmarshalError: failed to unmarshal error message
00000000  3c 68 74 6d 6c 3e 0d 0a  3c 68 65 61 64 3e 3c 74  |<html>..<head><t|
00000010  69 74 6c 65 3e 34 31 33  20 52 65 71 75 65 73 74  |itle>413 Request|
00000020  20 45 6e 74 69 74 79 20  54 6f 6f 20 4c 61 72 67  | Entity Too Larg|
00000030  65 3c 2f 74 69 74 6c 65  3e 3c 2f 68 65 61 64 3e  |e</title></head>|
00000040  0d 0a 3c 62 6f 64 79 3e  0d 0a 3c 63 65 6e 74 65  |..<body>..<cente|
00000050  72 3e 3c 68 31 3e 34 31  33 20 52 65 71 75 65 73  |r><h1>413 Reques|
00000060  74 20 45 6e 74 69 74 79  20 54 6f 6f 20 4c 61 72  |t Entity Too Lar|
00000070  67 65 3c 2f 68 31 3e 3c  2f 63 65 6e 74 65 72 3e  |ge</h1></center>|
00000080  0d 0a 3c 68 72 3e 3c 63  65 6e 74 65 72 3e 6f 70  |..<hr><center>op|
00000090  65 6e 72 65 73 74 79 2f  31 2e 31 39 2e 39 2e 31  |enresty/1.19.9.1|
000000a0  3c 2f 63 65 6e 74 65 72  3e 0d 0a 3c 2f 62 6f 64  |</center>..</bod|
000000b0  79 3e 0d 0a 3c 2f 68 74  6d 6c 3e 0d 0a           |y>..</html>..|

caused by: expected element type <Error> but have <html>

The object I've get this error on is:

ls -lah af/b3/f0ddaceb36dc2d716d83d7fee4ad_0ad-data_0.0.23.1-1.1_all.deb
-rw-r--r-- 1 debian debian 670M Dec 16 11:45 af/b3/f0ddaceb36dc2d716d83d7fee4ad_0ad-data_0.0.23.1-1.1_all.deb

It seems that the error is caused by the file being too large to be uploaded. Is there a way to configure Aptly to handle this situation, or is this a bug that needs to be addressed? Any guidance or assistance would be greatly appreciated.