as discussed in several chats, this PR starts making it possible to use
Webxdc as integrations to the main app. In other word: selected parts of
the main app can be integrated as Webxdc, eg. Maps [^1]
this PR contains two parts:
- draft an Webxdc Integration API
- use the Webxdc Integration API to create a Maps Integration
to be clear: a Webxdc is not part of this PR. the PR is about marking a
Webxdc being used as a Map - and core then feeds the Webxdc with
location data. from the view of the Webxdc, the normal
`sendUpdate()`/`setUpdateListener()` is used.
things are still marked as "experimental", idea is to get that in to
allow @adbenitez and @nicodh to move forward on the integrations into
android and desktop, as well as improving the maps.xdc itself.
good news is that we currently can change the protocol between Webxdc
and core at any point :)
# Webxdc Integration API
see `dc_init_webxdc_integration()` in `deltachat.h` for overview and
documentation.
rust code is mostly in `webxdc/integration.rs` that is called by other
places as needed. current [user of the API is
deltachat-ios](https://github.com/deltachat/deltachat-ios/pull/1912),
android/desktop will probably follow.
the jsonrpc part is missing and can come in another PR when things are
settled and desktop is really starting [^2] (so we won't need to do all
iterations twice :) makes also sense, when this is done by someone
actually trying that out on desktop
while the API is prepared to allow other types of integrations (photo
editor, compose tools ...) internally, we currently ignore the type. if
that gets more crazy, we probably also need a dedicated table for the
integrations and not just a single param.
# Maps Integration
rust code is mostly in `webxdc/maps_integration.rs` that is called by
`webxdc/integration.rs` as needed.
EDIT: the idea of having a split here, is that
`webxdc/maps_integration.rs` really can focus on the json part, on the
communication with the .xdc, including tests
this PR is basic implementation, enabling to move forward on
integrations on iOS, but also on desktop and android.
the current implementation allows already the following:
- global and per-chat maps
- add and display POIs
- show positions and tracks of the last 24 hours
the current maps.xdc uses leaflet, and is in some regards better than
the current android/desktop implementations (much faster, show age of
positions, fade out positions, always show names of POIs, clearer UI).
however, we are also not bound to leaflet, it can be anything
> [**screenshots of the current
state**](https://github.com/deltachat/deltachat-ios/pull/1912)
> 👆
to move forward faster and to keep this PR small, the following will go
to a subsequent PR:
- consider allowing webxdc to use a different timewindow for the
location
- delete POIs
- jsonrpc
[^1]: maps are a good example as anyways barely native (see android
app), did cause a lot of pain on many levels in the past (technically,
bureaucratically), and have a comparable simple api
[^2]: only going for jsonrpc would only make sense if large parts of
android/ios would use jsonrpc, we're not there
---------
Co-authored-by: link2xt <link2xt@testrun.org>
API now pretends that trashed messages don't exist.
This way callers don't have to check if loaded message
belongs to trash chat.
If message may be trashed by the time it is attempted to be loaded,
callers should use Message::load_from_db_optional.
Most changes are around receive_status_update() function
because previously it relied on loading trashed status update
messages immediately after adding them to the database.
If `delete_device_after` is configured, that period should be counted for webxdc instances from the
last status update, otherwise nothing prevents from deleting them. Use `msgs.timestamp_rcvd` to
store the last status update timestamp, it anyway isn't used for anything except displaying a
detailed message info. Also, as `ephemeral::select_expired_messages()` now also checks
`timestamp_rcvd`, we have an improvement that a message is guaranteed not to be deleted for the
`delete_device_after` period since its receipt. Before only the sort timestamp was checked which is
derived from the "sent" timestamp.
The limit is better enforced by webxdc distributors,
e.g. xdc store bots or actually email providers
to allow for experimentation with large frameworks
or porting existing apps and testing them
before reducing their size.
Besides that, the comment on WEBXDC_SENDING_LIMIT was outdated,
it was not updated when the limit was increased to 640 kB.
If a Delta Chat message has the Message-ID already existing in the db, but a greater "Date", it's a
resent message that can be deleted. Messages having the same "Date" mustn't be deleted because they
can be already seen messages moved back to INBOX. Also don't delete messages having lesser "Date" to
avoid deleting both messages in a multi-device setting.
send_webxdc_status_update JSON-RPC call
and corresponding Rust call sometimes fail in CI with
---
database is locked
Caused by:
Error code 5: The database file is locked
---
Adding more context to send_webxdc_status_update() errors
to better localize the error origin.
It can be used e.g. as a default in the file saving dialog. Also display the original filename in
the message info. For these purposes add Param::Filename in addition to Param::File and use it as an
attachment filename in sent emails.
Webxdc update messages may contain
long lines that get hard-wrapped
and may corrupt JSON if the message
is not encrypted.
base64-encode the update part
to avoid hard wrapping.
This is not necessary for encrypted
messages, but does not introduce
size overhead as OpenPGP messages
are compressed.
receive_imf() calls add_parts()
which INSERTs or UPDATEs the message using UPSERT [1].
It then uses last_insert_rowid() to get
the ID of the inserted message.
However, it is incorrect to use last_insert_rowid()
if an UPDATE was executed instead of INSERT.
The solution is to use `RETURNING id` clause
to make the UPSERT statement return message ID in any case [2].
The fix is tested in test_webxdc_update_for_not_downloaded_instance()
and with a debug_assert!.
[1] https://www.sqlite.org/lang_UPSERT.html
[2] https://sqlite.org/forum/forumpost/9ce3bc1c4a85c15f
Message.set_text() and Message.get_text() are modified accordingly
to accept String and return String.
Messages which previously contained None text
are now represented as messages with empty text.
Use Message.set_text("".to_string())
instead of Message.set_text(None).
Moved custom ToSql trait including Send + Sync from lib.rs to sql.rs.
Replaced most params! and paramsv! macro usage with tuples.
Replaced paramsv! and params_iterv! with params_slice!,
because there is no need to construct a vector.
To handle backups the UIs have to make sure they do stop the IO
scheduler and also don't accidentally restart it while working on it.
Since they have to call start_io from a bunch of locations this can be
a bit difficult to manage.
This introduces a mechanism for the core to pause IO for some time,
which is used by the imex function. It interacts well with other
calls to dc_start_io() and dc_stop_io() making sure that when resumed
the scheduler will be running or not as the latest calls to them.
This was a little more invasive then hoped due to the scheduler. The
additional abstraction of the scheduler on the context seems a nice
improvement though.
We do not make all transactions
[IMMEDIATE](https://www.sqlite.org/lang_transaction.html#deferred_immediate_and_exclusive_transactions)
for more parallelism -- at least read transactions can be made DEFERRED to run in parallel
w/o any drawbacks. But if we make write transactions DEFERRED also w/o any external locking,
then they are upgraded from read to write ones on the first write statement. This has some
drawbacks:
- If there are other write transactions, we block the thread and the db connection until
upgraded. Also if some reader comes then, it has to get next, less used connection with a
worse per-connection page cache.
- If a transaction is blocked for more than busy_timeout, it fails with SQLITE_BUSY.
- Configuring busy_timeout is not the best way to manage transaction timeouts, we would
prefer it to be integrated with Rust/tokio asyncs. Moreover, SQLite implements waiting
using sleeps.
- If upon a successful upgrade to a write transaction the db has been modified by another
one, the transaction has to be rolled back and retried. It is an extra work in terms of
CPU/battery.
- Maybe minor, but we lose some fairness in servicing write transactions, i.e. we service
them in the order of the first write statement, not in the order they come.
The only pro of making write transactions DEFERRED w/o the external locking is some
parallelism between them. Also we have an option to make write transactions IMMEDIATE, also
w/o the external locking. But then the most of cons above are still valid. Instead, if we
perform all write transactions under an async mutex, the only cons is losing some
parallelism for write transactions.
