This adds a parameter "events" to the /rest/events endpoint. It should
be a comma separated list of the events the consumer is interested in.
When not given it defaults to the current set of events, so it's
backwards compatible.
The API service then manages subscriptions, creating them as required
for each requested event mask. Old subscriptions are not "garbage
collected" - it's assumed that in normal usage the set of event
subscriptions will be small enough. Possibly lower than before, as we
will not set up the disk event subscription unless it's actually used.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/4092
This deprecates the current minDiskFreePct setting and introduces
minDiskFree. The latter is, in it's serialized form, a string with a
unit. We accept percentages ("2.35%") and absolute values ("250 k", "12.5
Gi"). Common suffixes are understood. The config editor lets the user
enter the string, and validates it.
We still default to "1 %", but the user can change that to an absolute
value at will.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/4087
LGTM: AudriusButkevicius, imsodin
After this change,
- Symlinks on Windows are always unsupported. Sorry.
- Symlinks are always enabled on other platforms. They are just a small
file like anything else. There is no need to special case them. If you
don't want to sync some symlinks, ignore them.
- The protocol doesn't differentiate between different "types" of
symlinks. If that distinction ever does become relevant the individual
devices can figure it out by looking at the destination when they
create the link.
It's backwards compatible in that all the old symlink types are still
understood to be symlinks, and the new SYMLINK type is equivalent to the
old SYMLINK_UNKNOWN which was always a valid way to do it.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/3962
LGTM: AudriusButkevicius
The monitor process should not set STNORESTART as this indicates the
intention from the user. Setting STMONITORED is enough, as this tells
the next Syncthing instance that it is running under the monitor
process.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/3932
The Ping event is important, as it means that requests complete within
a sensible time. The disk events API didn't have the Ping event, so
if there were no disk events, the request would keep taking forever.
Unless, of course, there's a reverse proxy which times the request out
after a suitably large interval (or something else aborts it), in which
case Syncthing isn't very happy.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/3929
Instead of
[I6KAH] 19:05:56 INFO: Single thread hash performance is 359 MB/s using minio/sha256-simd (354 MB/s using crypto/sha256).
it now says
[I6KAH] 19:06:16 INFO: Single thread SHA256 performance is 359 MB/s using minio/sha256-simd (354 MB/s using crypto/sha256).
[I6KAH] 19:06:17 INFO: Actual hashing performance is 299.01 MB/s
which is more informative. This is also the number it reports in usage
reporting.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/3918
Adds support for -auditfile= where is "-" for stdout, "--" for stderr, or a
filename. It can be left blank (or left out entirely) for the original
behaviour of creating a timestamped filename.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/3860
This avoids unnecessary browser request failures and retries. Eg:
- Browser reuses existing HTTP connection for GUI refresh request
- Server closes connection with request in flight
- Browser retries GET request.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/3854
This adds support for AES_256_GCM_SHA384 (in there since Go 1.5, a bit
of a shame we missed it) and ChaCha20-Poly1305 (if built with Go 1.8;
ignored on older Gos).
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/3822
Instead, trust (and test) that the temp file has appropriate permissions
from the start. The only place where this changes our behavior is for
ignores which go from 0644 to 0600. I'm OK with that.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/3756
The current way is quite confusing for new users - we create a default
folder, but it's not usable with the default folder created somewhere
else. Instead, when setting up for the first time with two devices, the
default folder must be removed and recreated on one of them. This comes
up on IRC and the forum now and then.
I think this matches expectactions better.
Another alternative would be to remove it entirely (not create a default
folder), but then we should also add some guidance in the UI on how to
proceed.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/3751
This makes the device ID a real type that can be used in the protobuf
schema. That avoids the juggling back and forth from []byte in a bunch
of places and simplifies the code.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/3695
This adds autodetection of the fastest hashing library on startup, thus
handling the performance regression. It also adds an environment
variable to control the selection, STHASHING=standard (Go standard
library version, avoids SIGILL crash when the minio library has bugs on
odd CPUs), STHASHING=minio (to force using the minio version) or unset
for the default autodetection.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/3617
When the GUI/API is bound to localhost, we enforce that the Host header
looks like localhost. This can be disabled by setting
insecureSkipHostCheck in the GUI config.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/3558
We used to consider deleted files & directories 128 bytes large. After
the delta indexes change a bug slipped in where deleted files would be
weighted according to their old non-deleted size. Both ways are
incorrect (but the latest change made it worse), as if there are more
files deleted than remaining data in the repo the needSize can be
greater than the globalSize, resulting in a negative completion
percentage.
This change makes it so that deleted items are zero bytes large, which
makes more sense. Instead we expose the number of files that we need to
delete as a separate field in the Completion() result, and hack the
percentage down to 95% complete if it was 100% complete but we need to
delete files. This latter part is sort of ugly, but necessary to give
the user some sort of feedback.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/3556
Furthermore:
1. Cleans configs received, migrates them as we receive them.
2. Clears indexes of devices we no longer share the folder with
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/3478
This adds a new nanoseconds field to the FileInfo, populates it during
scans and sets the non-truncated time in Chtimes calls.
The actual file modification time is defined as modified_s seconds +
modified_ns nanoseconds. It's expected that the modified_ns field is <=
1e9 (that is, all whole seconds should go in the modified_s field) but
not really enforced. Given that it's an int32 the timestamp can be
adjusted += ~2.9 seconds by the modified_ns field...
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/3431
This adds a config to enable debug functions on the API server, which is
by default disabled. When enabled, the /rest/debug things become
available and become available without requiring a CSRF token (although
authentication is required if configured).
We also add a new endpoint /rest/debug/cpuprof?duration=15s (with the
duration being configurable, defaulting to 30s). This runs a CPU profile
for the duration and returns it as a file. It sets headers so that a
browser will save the file with an informative name.
The same is done for heap profiles, /rest/debug/heapprof, which does not
take any parameters.
The purpose of this is that any user can enable debugging under
advanced, then point their browser to the endpoint above and get a file
that contains a CPU or heap profile we can use, with the filename
telling us what version and architecture the profile is from.
On the command line, this becomes
curl -O -J http://localhost:8082/rest/debug/cpuprof?duration=5s
curl: Saved to filename
'syncthing-cpu-darwin-amd64-v0.14.3+4-g935bcc0-110307.pprof'
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/3467
This used to happen by itself as the connecting device always sent an
Index message and we triggered on that. Nowadays there's no guarantee
for that, but we anyway need to send out one event to let listeners know
the state of folders shared with the device.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/3438
This slightly changes the interface used for committing configuration
changes. The two parts are now:
- VerifyConfiguration, which runs synchronously and locked, and can
abort the config change. These callbacks shouldn't *do* anything
apart from looking at the config changes and saying yes or no. No
change from previously.
- CommitConfiguration, which runs asynchronously (one goroutine per
call) *after* replacing the config and releasing any locks. Returning
false from these methods sets the "requires restart" flag, which now
lives in the config.Wrapper.
This should be deadlock free as the CommitConfiguration calls can take
as long as they like and can wait for locks to be released when they
need to tweak things. I think this should be safe compared to before as
the CommitConfiguration calls were always made from a random background
goroutine (typically one from the HTTP server), so it was always
concurrent with everything else anyway.
Hence the CommitResponse type is gone, instead you get an error back on
verification failure only, and need to explicitly check
w.RequiresRestart() afterwards if you care.
As an added bonus this fixes a bug where we would reset the "requires
restart" indicator if a config that did not require restart was saved,
even if we already were in the requires-restart state.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/3386
* relaypoolsrv/master: (32 commits)
Fetch deps of deps X_x
Here we go with gvt bugs
Screw godep
Add solaris support back in
Add font awesome
No value is less than zero
Screw solaris
Godeps
Refactor javascript, always show table, add sorting
Add local geoip
Update dependencies
Hey look, had to check all code out on linux to fix the deps
Update godeps, reduce amount of time spent testing a relay. Goddamit godeps.
Add timeouts, deal with overlapping markers, add a table, increase circle radiuses
Fix a couple of issues with the relays map (geoip, 'data unavailable')
Rate infos are in kbps, not kBps
Add support for header holding IP address
Update relay parameters even if it already exists (fixes#3)
Add missing space
Add homepage
...
This changes the BEP protocol to use protocol buffer serialization
instead of XDR, and therefore also the database format. The local
discovery protocol is also updated to be protocol buffer format.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/3276
LGTM: AudriusButkevicius
If the listen address scheme is set to tcp4:// or tcp6://, it needs to be
made sure that the remote address matches this scheme before it is added to
the database.
This prevents invalid URIs like tcp4://<IPv6 address>:<port> or tcp6://<IPv4
address>:<port>.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/3378
This contains the following behavioral changes:
- Duplicate folder IDs is now fatal during startup
- Invalid folder flags in the ClusterConfig is fatal for the connection
(this will go away soon with the proto changes, as we won't have any
unknown flags any more then)
- Empty path is a folder error reported at runtime
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/3370
Events API consumers rely on being able to detect that events were skipped
by the fact that the event ID has increased by more than 1. This is
documented, and is absolutely necessary when trying to maintain a local
model of Syncthing's state.
With the introduction of LocalChangeDetected, which is not exposed to the
Events API, this contract was broken.
This commit introduces separate concepts of a "Global ID" and a
"Subscription ID". The Global ID of an event is unique across all
subscriptions. The Subscription ID is local to a particular subscription,
and always increments by 1. They are both exposed over the Events API, but
the Subscription ID uses the key "id" for backwards compatibility, and
the "?since=xx" parameter refers to the Subscription ID (making the Global
ID for information only).
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/3351
LGTM: calmh
While attempting to fix#2782 I thought the problem was the
CheckFolderHealth method, so I cleaned it up. That turned out not to be
the case, but I think this is better anyhow.
It also moves the "create folder and marker if the folder was empty in
the index" code to StartFolder where I think it makes better sense.
This is covered by a number of existing tests.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/3343
The purpose of this operation is to separate the serving of GUI assets a
bit from the serving of the REST API. It's by no means complete. The end
goal is something like a combined server type that embeds a statics
server and an API server and wraps it in authentication and HTTPS and
stuff, plus possibly a named pipe server that only provides the API and
does not wrap in the same authentication etc.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/3273
This sacrifices the ability to return an error when creating the service
for being more persistent in keeping it running.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/3270
LGTM: AudriusButkevicius, canton7
As noted in the ticket I no longer agree that dev builds should not auto
upgrade. The main reason is that we give dev builds to users to test
specific fixes, and noone is happier by them being inadvertently stuck
on that version when a newer version including the fix is released.
For developers, it's first of all probably unlikely that development is
happening on a build that's older than release, and secondly STNOUPGRADE
can be set in the environment once and for all if it an issue.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/3244
* relaysrv/master: (60 commits)
Add new dependencies
Add more logging in the case of relaypoolsrv internal server error
Dependency update
Update deps
Update packages, fix testutil. Goddamit godep.
Typo
Add signal handlers (fixes#15)
Update readme (fixes#16)
Limit number of connections (fixes#23)
Enable extra logging in pool.go even when -debug not specified
Add Antony Male to CONTRIBUTORS
Allow extAddress to be set from the command line
URLs should have Go units
Add CORS headers
Fix units
Expose provided by in status endpoint
Add ability to advertise provider
Change the URL
Rename relaysrv binary, see #11
Jail the whole thing a bit more
...
* discosrv/master: (64 commits)
Use atomics for statistics handling (fixes#45)
Lower case JSON fields are nicer
Change v13 to v2
Remove explicit relay handling
Update vendored github.com/cznic/ql (fixes#34)
Defer fd.Close() (fixes#37)
There is no "get dependencies" step
Add vendor/golang.org/x/net/context
Use Go 1.5 vendoring instead of Godeps
Add debug performance logging per request
Must close result sets
Set Retry-After header
Ignores
lru.Cache is not concurrency safe
We need a limit on the number of PostgreSQL connections
Correct example DSN (fixes#29)
Allow plain HTTP serving behind a proxy
Fix Query/Answer stats
Reduce our patience with slow clients somewhat
Discovery server should print device ID of certificate at startup
...
With the previous setup, browsers were free to use a local cache for any
length of time they pleased: we didn't set an 'Expires' header (or max-age
directive), and Cache-Control just said "you're free to cache this".
Therefore be more explicit: we don't mind if browsers cache things, but they
MUST revalidate everything on every request.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/3221
The intention for this package is to provide a combination of the
security of crypto/rand and the convenience of math/rand. It should be
the first choice of random data unless ultimate performance is required
and the usage is provably irrelevant from a security standpoint.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/3186
We need to set these properties *before* Angular starts making requests,
and doing that from the response to a request is too late. The obvious
choice (to me) would be to use the angular $cookies service, but that
service isn't available until after initialization so we can't use it.
Instead, add a special file that is loaded by index.html and includes
the info we need before the JS app even starts running.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/3152
Without this the summary service doesn't know to recalculate completion
percentage for remote devices when DownloadProgress messages come in.
That means that completion percentage isn't updated in the GUI while
transfers of large files are ongoing. With this change, it updates
correctly.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/3144
I think this better reflects what it means. Also tweaks the verbose
format to be more like our other things and lightly refactors the code
to not have the boolean and include the folder in the event.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/3121
Because json.NewDecoder(r).Decode(&v) doesn't necessarily consume all
data on the reader, that means an HTTP connection can't be reused. We
don't do a lot of HTTP traffic where we read JSON responses, but the
discovery is one such place. The other two are for POSTs from the GUI,
where it's not exactly critical but still nice if the connection still
can be keep-alive'd after the request as well.
Also ensure that we call req.Body.Close() for clarity, even though this
should by all accounts not really be necessary.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/3050
1. Removes separate relay lists and relay clients/services, just makes it a listen address
2. Easier plugging-in of other transports
3. Allows "hot" disabling and enabling NAT services
4. Allows "hot" listen address changes
5. Changes listen address list with a preferable "default" value just like for discovery
6. Debounces global discovery announcements as external addresses change (which it might alot upon starting)
7. Stops this whole "pick other peers relay by latency". This information is no longer available,
but I don't think it matters as most of the time other peer only has one relay.
8. Rename ListenAddress to ListenAddresses, as well as in javascript land.
9. Stop serializing deprecated values to JSON
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/2982
This happens automatically in the background anyway, and it can take a
long time on low powered devices at an inconvenient time. We just want
to get up and running as quickly as possible.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/3000
A potential practical use is to encode a short version of the hostname
at the beginning of the device ID.
For example:
jb@syno:~/s/g/s/s/c/stvanity $ stvanity abc
Want 15 bits for prefix "ABC", about 3.3e+04 certs to test (statistically speaking)
Found ABCFPWS-JKDIFV3-E5IUAQW-DK53WVR-HY7XWBS-56H33GR-CJQI67Q-VGXRMAW
Saved to cert.pem, key.pem
jb@syno:~/s/g/s/s/c/stvanity $ stvanity $(hostname)
Want 20 bits for prefix "SYNO", about 1e+06 certs to test (statistically speaking)
Trying 554 certs/s, tested 8307 so far in 15s, expect ~32m total time to complete
Trying 543 certs/s, tested 16277 so far in 30s, expect ~32m total time to complete
...
The rest is just a matter of patience.
jb@syno:~/s/g/s/s/c/stvanity $ stvanity syncthing
Want 50 bits for prefix "SYNCTHI-NG", about 1.1e+15 certs to test (statistically speaking)
Trying 529 certs/s, tested 7941 so far in 15s, expect ~67443 years total time to complete
...
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/2986
When run without parameters, attempts to listen for local discovery
announcements just like Syncthing, and prints them.
With -send, it also sends fake discovery packets. This can be used on
two or more computers simultaneously to verify that they can see each
other.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/2985
This fixes both a race condition where we could assign s.stop from one
goroutine and then read it from another without locking, and handles the
fact that listener may be nil at shutdown if we've had a bad
CommitConfiguration call in the meantime.
This updates the modified time of the config file before archiving it
during an update so that the clean up routine doesn't delete it if it's
too old, preventing the user from being able to rollback after an
upgrade.
This gets rid of redundant checks and centralizes the logic of loading
the config files so that we don't have to keep doing the same thing in
multiple places.
I'm not really sure under what circumstances MkdirAll returns a nil
error but a subsequent stat fails, but apparently it can happen and we
need to handle it. The "mode >= 0" was a no-op, and we never call
ensureDir anyway without the intention of ensuring the mode, so removed
that.
This avoids the double negative of having noConsole = false to represent
not hiding the console. It is also consistent with the action performed
by osutils.
This takes advantage of the newly created parseCommandLineOptions()
function and makes it work so that it now returns a nice struct of
options rather than relying on global variables.
There are a few global variables left, but they will take a bit more
refactoring in order to be removed, so it'll happen in later commits.
ensureDir() did not handle one last error case and there was some logic
in the main() function that belonged to ensureDir() as well. It was also
creating a directory with a hardcoded 0700 mode, regardless of what mode
was passed to it.
This refactors it a little to fix the broken behavior, avoid redundant
checks by taking advantage of the behavior of MkdirAll, and move the
extra logic from main() into ensureDir().
The main() function is growing too big (142 lines as of the date of this
commit), so this attempts to extract some functionality out of there and
into their own functions to make it easier to reason about them and keep
functions short and concise.
--browser-only assumes syncthing is already running and will open the
user's browser in the URL:port currently used in the configuration if
the GUI is enabled.
Every time a JSON object is returned in an HTTP response, the
appropriate header needs to be set and the object itself needs to be
encoded. Doing this in every function is repetitive and error prone
(getDBFile and postDBScan, for instance, never set any headers).
This adds a helper function to centralize the appropriate JSON response
handling.
With this change, the behavior is as follows:
- SIGTERM / SIGINT: Exit cleanly (exit code 0)
- SIGHUP: Restart
This is the case both when hitting the monitor process or the inner
process, or if running with NORESTART (but then we won't restart,
obviously, just exit with code exitRestarting).
It enables "pkill -HUP syncthing" to do the right thing to restart all
Syncthings on package upgrade, for example.
Also fixes what I think migh thave been a bug where we did not use the
proxy for usage reports. And removes the BuildEnv field that we don't
need any more.
This replaces the current 3072 bit RSA certificates with 384 bit ECDSA
certificates. The advantage is these certificates are smaller and
essentially instantaneous to generate. According to RFC4492 (ECC Cipher
Suites for TLS), Table 1: Comparable Key Sizes, ECC has comparable
strength to 3072 bit RSA at 283 bits - so we exceed that.
There is no compatibility issue with existing Syncthing code - this is
verified by the integration test ("h2" instance has the new
certificate).
There are browsers out there that don't understand ECC certificates yet,
although I think they're dying out. In the meantime, I've retained the
RSA code for the HTTPS certificate, but pulled it down to 2048 bits. I
don't think a higher security level there is motivated, is this matches
current industry standard for HTTPS certificates.
- Move to ipinfo.io for geoip, rather than Telize. Telize has been closed
down. ipinfo.io has apparently got decent availability, and allows
1,000 requests per day on the free tier. Since requests are made by the
client, this should be more than enough (and the total across all clients
should still be less than this).
- Fix issue where one nonresponsive relay would cause 'data unavailable'
to be shown for many relays. This was caused by the relay status
promise not being correctly added to the list of things being waited
for before the map was rendered. Any delayed relay status requests
would therefore occur after the map was rendered, which was too late.
Knowing why a relay server failed to join the pool can be important. This
is typically an issue which must be investigated after it occurred, so
having logs available is useful.
Running with -debug permanently enabled is impractical, due to the amount
of traffic that is generated, particularly when data is being transferred.
Logging is limited to at most one message per minute, although one message
per hour is more likely.
This allows relaysrv to listen on an unprivileged port, with port
forwarding directing traffic from 443, thus providing an alternative
to using setcap cap_net_bind_service=+ep
We're going to need the db.Instance to keep some state, and for that to
work we need the same one passed around everywhere. Hence this moves the
leveldb-specific file opening stuff into the db package and exports the
dbInstance type.
'AlwaysLocalNets' was getting printed, but was getting used
when setting up connections. Now, the nets that should be
considered local are printed and used.
Overwriting configuration files is likely to happen if a
user syncs their home directories across computers. In this
case, the biggest risk is that all nodes will end up with
the same certificate and thus Device ID.
When the model prepares a folder for syncing, it checks to
see if the configuration files this instance is using are
getting synced. If the are getting synced, and they aren't
getting ignored, a warning is emitted. The model is used
so that when a new folder is added dynamically, a warning
is also emitted.
This will not prevent a user from shooting themselves in
the foot, and will not cover all cases (e.g. symlinks).
It should provide _something_ for many users in this
situation to go on, though.
Add WorkingDirectory to create and use the certificates within
/var/lib/syncthing-relaysrv. Add RootDirectory to chroot(2) the whole
thing into that directory.
This implements a new debug/trace infrastructure based on a slightly
hacked up logger. Instead of the traditional "if debug { ... }" I've
rewritten the logger to have no-op Debugln and Debugf, unless debugging
has been enabled for a given "facility". The "facility" is just a
string, typically a package name.
This will be slightly slower than before; but not that much as it's
mostly a function call that returns immediately. For the cases where it
matters (the Debugln takes a hex.Dump() of something for example, and
it's not in a very occasional "if err != nil" branch) there is an
l.ShouldDebug(facility) that is fast enough to be used like the old "if
debug".
The point of all this is that we can now toggle debugging for the
various packages on and off at runtime. There's a new method
/rest/system/debug that can be POSTed a set of facilities to enable and
disable debug for, or GET from to get a list of facilities with
descriptions and their current debug status.
Similarly a /rest/system/log?since=... can grab the latest log entries,
up to 250 of them (hardcoded constant in main.go) plus the initial few.
Not implemented in this commit (but planned) is a simple debug GUI
available on /debug that shows the current log in an easily pasteable
format and has checkboxes to enable the various debug facilities.
The debug instructions to a user then becomes "visit this URL, check
these boxes, reproduce your problem, copy and paste the log". The actual
log viewer on the hypothetical /debug URL can poll regularly for new log
entries and this bypass the 250 line limit.
The existing STTRACE=foo variable is still obeyed and just sets the
start state of the system.
Not necessarily the easiest way to fix just this bug, but the root cause
was using the (at that point uninitialized) cfg variable, so it seemed
sensible to just get rid of it to avoid that kind of crap.
The connections service no longer depends directly on the
syncthing model object, but on an interface instead. This
makes it drastically easier to write clients that handle
the model differently, but still want to benefit from
existing and future connections changes in the core.
This was motivated by burkemw3's interest in creating a
FUSE client that can present a view of the global model,
but not have all of the file data locally.
The actual decoupling was done by adding a connections.Model
interface. This interface is effectively an extension of the
protocol.Model interface that also handles connections
alongside the modified service.
