On Fri, Apr 14, 2023 at 3:19 AM Fujii Masao <masao.fu...@oss.nttdata.com> wrote: > On 2023/04/13 15:13, Etsuro Fujita wrote: > > I am not 100% sure that it is a good idea to use the same error > > message "could not send cancel request" for the PQgetCancel() and > > PQcancel() cases, because they are different functions. How about > > "could not create PGcancel structure” or something like that, for the > > The primary message basically should avoid reference to implementation > details such as specific structure names like PGcancel, shouldn't it, as per > the error message style guide?
I do not think that PGcancel is that specific, as it is described in the user-facing documentation [1]. (In addition, the error message I proposed was created by copying the existing error message "could not create OpenSSL BIO structure" in contrib/sslinfo.c.) > > former case, so we can distinguish the former error from the latter? > > Although the primary message is the same, the supplemental message provides > additional context that can help distinguish which function is reporting the > message. If the user is familiar with the PQgetCancel/PQcancel internals, this is true, but if not, I do not think this is always true. Consider this error message, for example: 2023-04-14 17:48:55.862 JST [24344] WARNING: could not send cancel request: invalid integer value "99999999999" for connection option "keepalives" It would be hard for users without the knowledge about those internals to distinguish that from this message. For average users, I think it would be good to use a more distinguishable error message. Best regards, Etsuro Fujita [1] https://www.postgresql.org/docs/current/libpq-cancel.html
