Currently there is a period of pain whenever we make
backward-incompatible changes to the structured output format, which
discourages not only backward-incompatible improvements to the format,
but also backwards-compatible additions that may not be "perfect". In
the end, these problems limit experimentation and innovation.
This series of patches introduces a way for CLI callers to request a
specific format version on the command line and to determine if the
CLI does not supported the requested version (and perhaps present a
useful diagnostic to the user). Since the caller requests a format
version, it's also possible for the CLI to support multiple
incompatible versions simultaneously, unlike the alternate approach of
including version information in the output.
This patch lays the groundwork by introducing a versioning convention,
standard exit codes, and a utility function to check the requested
version and produce standardized diagnostic messages and exit
statuses.
All the structured output functions in notmuch-reply and notmuch-show
are renamed to a generic name (as they do not contain any json-specific
code anyway). This patch is a preparation to actually using the new
S-Expression sprinter in notmuch-reply and notmuch-show.
Previously body: was a compulsory field in a message. The new
--body=false option causes notmuch show to omit this field so update
schemata to reflect this.
In id:"87sjdm12d1.fsf@awakening.csail.mit.edu" Austin pointed out that
devel/schemata needs a slight correction with the new
--entire-thread=false option. This is that correction.
