@node chainqueue-tx
@section Transaction representation

Transactions in chainqueue are chain-agnostic. Their representation should only presume a generalized concept of a chain transaction. Interpretation of what a transaction acutally contains or means is left to the client code of the queue to process.

In storage each record is divided into two parts: A @emph{mandatory} part, and a @emph{cache} part.


@subsection Mandatory record

This consists of the data required to order transactions, and to actually them to the network. Specifically, it contains:

@itemize
@item @strong{hash} of the transaction
@item the serialized transaction @strong{payload}
@item the transaction @strong{nonce} 
@item the @xref{chainqueue-states, queue state}
@item the @strong{block number} of a confirmed transaction
@end itemize


@subsection Cache record

With exception of the @emph{nonce}, the @emph{cache} part of the record contains deserialized fields of the transaction, all of which can be reconstructed by the client code intepreting the transaction payload in the @emph{mandatory} part.

The queue can still work without the cache record, but keeping one enables conditional ordering and execution, e.g. @emph{@guillemetleft{}the first unsent transaction nonce from sender S.@guillemetright{}}

Additionally, the cache records curates some additional token semantics, defining in essence a transaction as @emph{@guillemetleft{}sender S sends X amount of token A as Y amount of token B to recipient R@guillemetright{}}.