This fixes a nasty bug where exporting messages sent by a single user
might only contain some of the messages in the event that the
unspecified sort order by the database didn't happen to be sorted by
message ID.
This commit only addresses tables that currently derive from
user_profile_config in get_realm_config:
zerver_userpresence
zerver_useractivity
zerver_useractivityinterval
zerver_subscription
zerver_recipient
zerver_stream
zerver_huddle
It also introduces an entry in realm.json for a virtual
table called "zerver_userprofile_mirrordummy" for dummy users,
which include prior dummy users and users excluded from the call
to do_export_realm().
Note that this feature is not yet exposed in the management command.
Now attachment data gets written to its own json file. We are
splitting this out so that will be easier for us to cross-check
attachments against messages without holding up writing a lot
of the other realm data. (message cross-checking is coming soon)
This commit doesn't change any behavior; it just moves fetching
attachments out of the Config scheme and into its own method.
This prepares us to start writing attachment data to its own
file and cross-checking against message ids (coming soon).
We now just have a single configuration get_realm_config() that
handles most of the top-down realm export tables. (It basically
does everything not related to messages or uploads/avatars.)
Unifying the configs allows us to be more strict in our
configuration about checking for anomalies. In the future
we may need to loosen up some of those restrictions again,
but for now we are picky and paranoid.
Fetch stream data only for stream recipients, instead of
getting streams via realm_id.
(This change is kind of moot for now, since our stream recipients
include all possible stream recipients in the realm, but this
sets us up for when we start restricting users that we export
within the realm.)
This commit introduces the ability to do custom fetches
and to essentially use temp tables for intermediate results.
(The temp table stuff deals with recipients/subscriptions
having three different flavors--user, stream, and huddle.)
The function to create the message partial files has been
renamed to export_partial_message_files(). It now gets its own
list of user profile ids and recipient ids from the response,
so that we can de-clutter do_export_realm().
The name avatar_bucket was confusing for a boolean, and
in some places it was used for non-S3 paths.
I considered the more concise 'is_avatar', but that
was still confusing when you are processing multiple
files, because you think it's a calculated property
on one file instead of an overall codepath switch.
I also considered splitting up some functions, but
there is a lot of common logic between handling
file uploads and avatars that's not trivial to extract
into helpers, especially on the S3 side.
I did some minor moving around of code that made us have
one fewer function without any additional conditional
logic. The names are more explicit about saying
"from_local" and "from_s3". Also, there is less clutter
now in do_export_realm(), which is evolving into more of
a dispatcher and less of a worker.
This is pretty minor cleanup, but it makes it a little more
explicit what we're writing to the shard file, and it allows
us to use a more specific mypy type when calling
floatify_datetime_fields.
We no longer have an in-process code path to export
UserMessage rows. We want to only maintain the
subprocess code, which we'll always use in production,
and which will work fine in dev.
