This should reduce live stream latency by two seconds when my cameras
are at their default setting (I frame interval = 2 * frame rate)!
I was under the impression that every HTML5 Media Source Extensions
media segment had to start with a Random Access Point. This used to
be true, but apparently changed quite a while ago:
https://bugs.chromium.org/p/chromium/issues/detail?id=229412
Support generating segments that don't start with a key frame, and
plumb this through the mp4 media segment generation logic. Add some
extra error checking in mp4 slice handling, as my first attempts had a
mismatch between expected and actual lengths that silently returned
corrupted .m4s files.
Also pull everything from the most recent key frame on along with the
first live segment to reduce startup latency. Live view is quite a bit
more pleasant now.
* As discussed in #48, say "The Moonfire NVR Authors" at the top of
every file rather than whoever created that file. Have one AUTHORS
file listing everyone.
* Consistently call it a "security camera network video recorder" rather
than "security camera digital video recorder".
This addressed a deprecation warning on nightly (will be in Rust 1.38).
Use parking_lot instead, which in theory is faster (although I doubt
it's significant here).
Now the test actually has a recording and garbage with matching files.
This caught a few problems in the upgrade procedure:
* it didn't work with foreign keys enabled because the new recording
table was set up after the new camera table, and the old recording
table was destroyed after the old camera table. And now I enable
foreign keys all the time. Reorder the procedure to fix.
* the pathname manipulation in the v2 to v3 procedure was incorrect
since my introduction of nix because I gave it a &[u8] with the
trailing nul, where I should have used CStr::from_bytes_with_nul.
* it wasn't removing garbage files. It'd be most natural to do this
in the v2 to v3 upgrade (with the rename) but I historically removed
the table when upgrading to v2. I can't redefine the schema now, so
do it unnaturally.
I'm considering also renaming all uuid-like files on upgrade to v4/v5
to clean up this mess automatically for installations that have
already done this upgrade.
My dad's "GW-GW4089IP" cameras use separate ports for the main and sub
streams:
rtsp://192.168.1.110:5050/H264?channel=0&subtype=0&unicast=true&proto=Onvif
rtsp://192.168.1.110:5049/H264?channel=0&subtype=1&unicast=true&proto=Onvif
Previously I could get one of the streams to work by including :5050 or
:5049 in the host field of the camera. But not both. Now make the
camera's host field reflect the ONVIF port (which is also non-standard
on these cameras, :85). It's not directly used yet but probably will be
sooner or later. Make each stream know its full URL.
I went with the third idea in 1ce52e3: have the tests run each iteration
of the syncer explicitly. These are messy tests that know tons of
internal details, but I think they're less confusing and racy than if I
had the syncer running in a separate thread.
This is mostly just "cargo fix --edition" + Cargo.toml changes.
There's one fix for upgrading to NLL in db/writer.rs:
Writer::previously_opened wouldn't build with NLL because of a
double-borrow the previous borrow checker somehow didn't catch.
Restructure to avoid it.
I'll put elective NLL changes in a following commit.
Some caveats:
* it doesn't record the peer IP yet, which makes it harder to verify
sessions are valid. This is a little annoying to do in hyper now
(see hyperium/hyper#1410). The direct peer might not be what we want
right now anyway because there's no TLS support yet (see #27). In
the meantime, the sane way to expose Moonfire NVR to the Internet is
via a proxy server, and recording the proxy's IP is not useful.
Maybe better to interpret a RFC 7239 Forwarded header (and/or
the older X-Forwarded-{For,Proto} headers).
* it doesn't ever use Secure (https-only) cookies, for a similar reason.
It's not safe to use even with a tls proxy until this is fixed.
* there's no "moonfire-nvr config" support for inspecting/invalidating
sessions yet.
* in debug builds, logging in is crazy slow. See libpasta/libpasta#9.
Some notes:
* I removed the Javascript "no-use-before-defined" lint, as some of
the functions form a cycle.
* Fixed#20 along the way. I needed to add support for properly
returning non-OK HTTP statuses to signal unauthorized and such.
* I removed the Access-Control-Allow-Origin header support, which was
at odds with the "SameSite=lax" in the cookie header. The "yarn
start" method for running a local proxy server accomplishes the same
thing as the Access-Control-Allow-Origin support in a more secure
manner.
I moved the clocks member from LockedDatabase to Database to make this happen,
so the new DatabaseGuard (replacing a direct MutexGuard<LockedDatabase>) can
access it before acquiring the lock.
I also made the type of clock a type parameter of Database (and so several
other things throughout the system). This allowed me to drop the Arc<>, but
more importantly it means that the Clocks trait doesn't need to stay
object-safe. I plan to take advantage of that shortly.
* separate these out into a new file, writer.rs, as dir.rs was getting
unwieldy.
* extract traits for the parts of SampleFileDir and std::fs::File they needed;
set up mock implementations.
* move clock.rs to a new base crate to be accessible from the db crate.
* add tests that exercise all the retry paths.
* bugfix: account for the new recording's bytes when calculating how much to
delete.
* bugfix: when retrying an unlink failure in collect_garbage, we shouldn't
warn about all the recordings no longer existing. Do this by retrying each
step rather than the whole procedure again.
* avoid double-panic scenarios, which I hit while tweaking the mocks. These
are quite annoying to debug as Rust doesn't print information about either
panic. I ended up using lldb to get a backtrace. Better to be cautious about
what we're doing when already panicking.
* give more context on raw::insert_recording errors, which I hit as well while
tweaking the new tests.
This was considering them as 0, so it would under-delete until the next flush
them delete all at once. That effectively doubled the number of bytes not yet
deleted as they're first transferred to garbage, flushed again, then unlinked.
I mistakenly thought these had to be monomorphized. (The FnOnce still
does, until rust-lang/rfcs#1909 is implemented.) Turns out this way works
fine. It should result in less compile time / code size, though I didn't check
this.
This needs a separate run of "cargo +nightly bench --features=nightly", so I
missed it in a couple previous commits. I probably should set up travis-ci...
This improves the practicality of having many streams (including the doubling
of streams by having main + sub streams for each camera). With these tuned
properly, extra streams don't cause any extra write cycles in normal or error
cases. Consider the worst case in which each RTSP session immediately sends a
single frame and then fails. Moonfire retries every second, so this would
formerly cause one commit per second per stream. (flush_if_sec=0 preserves
this behavior.) Now the commits can be arbitrarily infrequent by setting
higher values of flush_if_sec.
WARNING: this isn't production-ready! I hacked up dir.rs to make tests pass
and "moonfire-nvr run" work in the best-case scenario, but it doesn't handle
errors gracefully. I've been debating what to do when writing a recording
fails. I considered "abandoning" the recording then either reusing or skipping
its id. (in the latter case, marking the file as garbage if it can't be
unlinked immediately). I think now there's no point in abandoning a recording.
If I can't write to that file, there's no reason to believe another will work
better. It's better to retry that recording forever, and perhaps put the whole
directory into an error state that stops recording until those writes go
through. I'm planning to redesign dir.rs to make this happen.
It should reduce compile time / memory usage to put quite a bit of the code
into a separate crate. I also intend to limit visibility of some things to
only within the db crate, but that's for a future change. This is the smallest
move that will compile.
