mckero 7ac54f0a37 fix(aprs): report a failed send as failed, and a refused login as refused
Two defects made every APRS failure invisible. sendPacket ended with
`.getOrElse { Pair(true, "OK") }`, so a read that threw - including on a dead
socket - was reported as a successful send. And the login check threw inside a
runCatching whose result was discarded, so a server that refused to verify the
passcode could not propagate: aprsc keeps such a client connected and its writes
succeed while silently discarding every packet, which the app reported as success.
An audit put it plainly - twelve commits are all fix(aprs), none added a
socket-level test, so "it worked" was never evidence a packet had landed.

sendPacket now separates the cases. A read timeout stays a success, because
APRS-IS does not acknowledge position reports and silence is the normal outcome.
A closed stream or an IOException is a failure. The catch order matters and is
load-bearing: SocketTimeoutException extends IOException, so reversing them would
mark every normal report as failed.

The login handshake follows the spec: read the server's identification line first,
then log in, then read until a verdict arrives. AprsLogin holds that as pure logic
in core:domain with the parsing that decides it, including one trap worth naming -
"unverified" contains "verified", so the negative has to be tested first or every
refusal reads as acceptance. An explicit refusal now fails the report and shows
the operator its own message pointing at the callsign and passcode, in five
locales. A response we could not parse does not, since the packets may well be
landing and blaming the passcode would send them to fix something that works.

Three defects came out of review after that. The verdict is now bounded by a
deadline rather than a five-line budget, because a server that sent six keepalives
before its answer turned an accepted login into Unknown - telling the operator
their passcode was wrong when it had just been accepted. The greeting gets a short
two-second probe instead of the full login window, which cost eight seconds on
every connect to a server that sends none. And a refusal detected in the greeting
now aborts the connection instead of being overwritten by the next read, which had
made that branch and its comment a lie.

The worst of the three was mine: rewriting the write as print + flush dropped the
line terminator entirely. APRS-IS is a line protocol, so the server's reader never
saw a packet, while the send reported success and the read timed out into the
"silence is normal" branch. It broke healthy connections rather than dead ones and
was designed to have no symptom. Both the packet and the login line now end in an
explicit CRLF as the spec requires, rather than println's platform separator.

That defect is why this adds AprsIsClientSocketTest, which runs the client against
a stand-in server and reads the bytes back: it asserts two packets arrive as two
lines, that a login line arrives complete, that keepalive chatter does not bury the
verdict, that a greeting-less server connects promptly, and that a send to a closed
peer reports failure. Nothing in the pure-logic tests could have caught a missing
newline. Note for anyone extending it: closing the ServerSocket leaves an
established connection alive, so the dead-peer test has to close the accepted
socket - assuming otherwise made a correct implementation look broken.

AprsPacket.formatLogin is deleted, its work moved into AprsLogin.line, which also
replaces spaces in the version string because the server splits that field on
whitespace and the shipped value contained one.
2026-08-25 10:30:41 +00:00

Look4Sat: Satellite tracker

Look4Sat CI

Get it on Google Play Get it on F-Droid

Radio satellite tracker and pass predictor for Android, inspired by Gpredict

Track satellite passes with ease!

Thanks to Celestrak and SatNOGS you have access to over 9000 active satellites.
You can search the entire database by NORAD Catalog Number or the satellite's name.

Orbital positions and passes are calculated relative to your location.
To get reliable data make sure to set the station position via the app Settings.

The application is built using Kotlin, Coroutines, Jetpack Compose and Navigation.
It is now and always will be completely ad-free and open-source.

Main features:

  • Predicting satellite positions and passes for up to 10 days
  • Showing the list of currently active and upcoming satellite passes
  • Showing the active pass progress, polar trajectory and transceivers info
  • Showing the satellite positional data, footprint and ground track on the map
  • Custom TLE satellite data import is available via Three Line Element .txt files
  • Offline first: calculations are made offline. Weekly TLE data update is recommended.

License

The Look4Sat application code is licensed under the GNU General Public License v3.0.

The CW decoder in feature/cw bundles the DeepCW neural decoding model, licensed under the GNU Affero General Public License v3.0 only (AGPL-3.0-only). Because the combined work incorporates an AGPL-3.0 component, the combined work is distributed under the GNU Affero General Public License v3.0 — GPL-3.0 Section 13 permits the combination, and AGPL-3.0 Section 13 applies to the combined work as a whole. Model provenance and attribution are documented in feature/cw/licenses/NOTICE.md; the original GPL-3.0 text is preserved at feature/cw/licenses/Look4Sat-GPL-3.0.txt. The CW model runs locally on-device and does not provide services over a network.

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Description
Satellite tracker and pass predictor for Android, inspired by Gpredict
https://play.google.com/store/apps/details?id=com.rtbishop.look4sat
Readme AGPL-3.0
55 MiB
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v4.6.2
Latest
2026-08-27 15:47:20 +00:00
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