Dear Yuval!
The message format you tried to use is the standard one (the one being emitted from boto3, or any other AWS SDK [1]). It passes the arguments using 'x-www-form-urlencoded'. For example:
Thank you for your clarification! I've previously tried it as a x-www-form-urlencoded-body as well, but I have failed. That it was then working using the non-standard-parameters has lead me down the wrong road... But I have to admit that I'm still failing to create a topic the S3-way. I've tried it with curl, but as well with Postman. Even if I use your example-body, Ceph keeps telling me (at least) method-not-allowed. Is this maybe because I'm using an AWS Sig v4 to authenticate? This is the request I'm sending out: POST / HTTP/1.1 Content-Type: application/x-www-form-urlencoded; charset=utf-8 Accept-Encoding: identity Date: Tue, 23 Apr 2020 05:00:35 GMT X-Amz-Content-Sha256: e8d828552b412fde2cd686b0a984509bc485693a02e8c53ab84cf36d1dbb961a Host: s3.example.com X-Amz-Date: 2 as0200423T050035Z Authorization: AWS4-HMAC-SHA256 Credential=DNQXT3I8Z5MWDJ1A8YMP/20200423/de/s3/aws4_request, SignedHeaders=accept-encoding;content-type;date;host;x-amz-content-sha256;x-amz-date, Signature=fa65844ba997fe11e65be87a18f160afe1ea459892316d6060bbc663daf6eace User-Agent: PostmanRuntime/7.24.1 Accept: */* Connection: keep-alive Content-Length: 303 Name=ajmmvc-1_topic_1& Attributes.entry.2.key=amqp-exchange& Attributes.entry.1.key=amqp-ack-level& Attributes.entry.2.value=amqp.direct& Version=2010-03-31& Attributes.entry.3.value=amqp%3A%2F%2F127.0.0.1%3A7001& Attributes.entry.1.value=none& Action=CreateTopic& Attributes.entry.3.key=push-endpoint This is the response that comes back: HTTP/1.1 405 Method Not Allowed Content-Length: 200 x-amz-request-id: tx000000000000000000001-005ea12159-6e47a-s3-datacenter Accept-Ranges: bytes Content-Type: application/xml Date: Thu, 23 Apr 2020 05:02:17 GMT <?xml version="1.0" encoding="UTF-8"?><Error><Code>MethodNotAllowed</Code><RequestId>tx000000000000000000001-005ea12159-6e47a-s3-datacenter</RequestId><HostId>6e47a-s3-datacenter-de</HostId></Error> This is was radosgw is seeing at the same time 2020-04-23T07:02:17.745+0200 7f5aab2af700 20 final domain/bucket subdomain= domain=s3.example.com in_hosted_domain=1 in_hosted_domain_s3website=0 s->info.domain=s3.example.com s->info.request_uri=/ 2020-04-23T07:02:17.745+0200 7f5aab2af700 10 meta>> HTTP_X_AMZ_CONTENT_SHA256 2020-04-23T07:02:17.745+0200 7f5aab2af700 10 meta>> HTTP_X_AMZ_DATE 2020-04-23T07:02:17.745+0200 7f5aab2af700 10 x>> x-amz-content-sha256:e8d828552b412fde2cd686b0a984509bc485693a02e8c53ab84cf36d1dbb961a 2020-04-23T07:02:17.745+0200 7f5aab2af700 10 x>> x-amz-date:20200423T050035Z 2020-04-23T07:02:17.745+0200 7f5aab2af700 20 req 1 0s get_handler handler=26RGWHandler_REST_Service_S3 2020-04-23T07:02:17.745+0200 7f5aab2af700 10 handler=26RGWHandler_REST_Service_S3 2020-04-23T07:02:17.745+0200 7f5aab2af700 2 req 1 0s getting op 4 2020-04-23T07:02:17.745+0200 7f5aab2af700 10 Content of POST: Name=ajmmvc-1_topic_1& Attributes.entry.2.key=amqp-exchange& Attributes.entry.1.key=amqp-ack-level& Attributes.entry.2.value=amqp.direct& Version=2010-03-31& Attributes.entry.3.value=amqp%3A%2F%2F127.0.0.1%3A7001& Attributes.entry.1.value=none& Action=CreateTopic& Attributes.entry.3.key=push-endpoint 2020-04-23T07:02:17.745+0200 7f5aab2af700 10 Content of POST: Name=ajmmvc-1_topic_1& Attributes.entry.2.key=amqp-exchange& Attributes.entry.1.key=amqp-ack-level& Attributes.entry.2.value=amqp.direct& Version=2010-03-31& Attributes.entry.3.value=amqp%3A%2F%2F127.0.0.1%3A7001& Attributes.entry.1.value=none& Action=CreateTopic& Attributes.entry.3.key=push-endpoint 2020-04-23T07:02:17.745+0200 7f5aab2af700 10 Content of POST: Name=ajmmvc-1_topic_1& Attributes.entry.2.key=amqp-exchange& Attributes.entry.1.key=amqp-ack-level& Attributes.entry.2.value=amqp.direct& Version=2010-03-31& Attributes.entry.3.value=amqp%3A%2F%2F127.0.0.1%3A7001& Attributes.entry.1.value=none& Action=CreateTopic& Attributes.entry.3.key=push-endpoint 2020-04-23T07:02:17.745+0200 7f5aab2af700 1 handler->ERRORHANDLER: err_no=-2003 new_err_no=-2003 2020-04-23T07:02:17.745+0200 7f5aab2af700 2 req 1 0s http status=405 2020-04-23T07:02:17.745+0200 7f5aab2af700 1 ====== req done req=0x7f5aab2a6d50 op status=0 http_status=405 latency=0s ====== Best Regards, Andreas