Peppol Reporting - ExchangeTime

[dladlk]

Regarding https://github.com/OxalisCommunity/oxalis/wiki/Peppol-Reporting-%E2%80%90-WIP statement about "eb:UserMessage/eb:MessageInfo/eb:Timestamp" for transaction reporting - I am a little confused.

As far as I see it by enabling logback.xml <logger name="org.apache.cxf" level="debug"/> , NEITHER receiver's inboundMetadata.getTimestamp() nor sender's transmissionResponse.getTimestamp() return this value.

Moreover, they return DIFFERENT values:

• for receiver inboundMetadata.getTimestamp() returns SignalMessage/MessageInfo/Timestamp value (which I think is the only correct one)
• for sender TransmissionResponse.getTimestamp() returns timestamp when the object was created.

Example

Sender UserMessage/MessageInfo/Timestamp	2024-01-25T11:49:36.607+02:00
Receiver metadata.timestamp	2024-01-25T11:49:37.199+02:00
Receiver SignalMessage/MessageInfo/Timestamp	2024-01-25T11:49:37.199+02:00
Sender response.timestamp	2024-01-25T11:49:37.508+02:00

Code proofs

For sender: in TransmissionResponseConverter you can see, that parsed SignalMessage is used ONLY to get RefMessageId and potential errors - but timestamp is generated via timestampProvider which just creates a new date. That is why a sender will get ANOTHER date.

For receiver: in As4InboundHandler you can see, that UserMessage is parsed AFTER timestamp was generated via timestampProvider and only binary signature is passed there, so it is unable in any way to get original UserMessage timestamp - but just generates a new date.

So, in my opinion, the wiki page should be updated and mention that it is not eb:UserMessage/eb:MessageInfo/eb:Timestamp but eb:SignalMessage/eb:MessageInfo/eb:Timestamp should be used for transaction statistics, as SignalMessage with Receipt inside confirms that the document was received and that is the date which can be shared between sender and receiver. And at least that is the date that receiver gets at current version...

Additionally, Oxalis should be modified to return SignalMessage Timestamp as a part of As4TransmissionResponse.

It would be good to extend As4InboundHandler in BOTH As4InboundMetadata AND As4PayloadHeader, so receiver code get it additionally on attachment persistence phase (which in Peppol is always one) - and does not wait for inboundMetadata persistance. Actually, for our integration, we extended payload persistence with full UserMessage AND sender certificate... For senders, we extended As4TransmissionResponse with full Messaging object, received in response, so sender gets a proper timestamp.

Please correct me if I am wrong - looking forward for comments.

E.g. I did not manage to find where TSR or EUSR mention "UserMessage". Do they clearly define what should be used as a basis for periods? Maybe there are some comments from authors?

I suspect Peppol admins will try to match statistics from counter-parties, and definitely will get discrepancies for documents sent around midnight UTC.

[dladlk]

eb:UserMessage/eb:MessageInfo/eb:Timestamp was mentioned in Peppol Reporting - Service Provider Operational Guideline (version 1.0.2 from 15.01.2024 at the moment of writing) in section 3.2.1. "Timing of Exchange":

That is not what Oxalis receiver gets in Receiver metadata.timestamp(). To fix it, Oxalis-AS4 can be modified in As4InboundHandler.java to use userMessage.getMessageInfo().getTimestamp() (e.g. if it is not null - otherwise timestamp generated at the beginning of handle method).