docker-acars2pos

A Docker image which ingests JSON formatted ACARS, VDLM2, and HFDL messages and parses them for position data. Any positions found are output on a TCP port in SBS/Basestation format.

Under active development, everything is subject to change without notice.

Squawk Codes:

• First Digit
  • 1 = ACARS
  • 3 = VDL
  • 4 = VDL XID position
  • 5 = HFDL
  • 6 = HFDL position
• Second Digit
  • 0 = message not decoded by airframes library
  • 1 = message decoded by airframes library
  • 2 = message decoded by airframes library with position
• Third Digit
  • 0 = no position from python regexes
  • 1 = position from matching message label regex
  • 2 = position from a different message label regex
  • 3 = position from unlabeled regex

---

Environment Variables

Variable	Description	Default
JSON_IN	Semi-colon separated list of host:port entries to connect to for JSON ingest.	acars_router:15550
SBS_OUT	Semi-colon separated list of host:port entries to connect to for SBS/Basestation output.	ultrafeeder:12000
MIN_LOG_LEVEL	Minimum severity to log. See Logging.	6 (log everything)
LOG_FILE	Set to any value to message text, type, SBS output, and adsbexchange link to files in /log.	Unset
LAT	Latitude of receiver. Only required if MAX_DIST > 0	Unset
LON	Longitude of receiver. Only required if MAX_DIST > 0	Unset
MAX_DIST	Set this to a nonzero value to reject parsed positions that are too far away. Only applies to positions parsed from message text.	0
DIST_UNIT	The unit of the value in MAX_DIST. One of km, m, mi, nmi, ft, in.	nmi
SEND_ALL	Set to any value to send SBS messages for messages without a position. Set to log to also print a log entry for each non-position message.	Unset
ACARS_FREQ_AS_SQUAWK, VDLM2_FREQ_AS_SQUAWK, HFDL_FREQ_AS_SQUAWK	Set to any value to send the received frequency as the squawk value, for each incoming message type.	Unset
ACARS_FREQ_AS_ALT, VDLM2_FREQ_AS_ALT, HFDL_FREQ_AS_ALT	Set to any value to send the received frequency as the altitude value, for each incoming message type.	Unset

Logging

By default this container logs every message it decodes, which works out to roughly five lines of output per received message and makes docker logs impractical to read. MIN_LOG_LEVEL sets the minimum severity that is printed.

Value	Name	What it adds
1	fatal	Only errors that stop the script.
2	error	Failures decoding a message.
3	warn	Lost or refused connections, malformed input.
4	info	Startup and connect/reconnect messages. Recommended.
5	debug	Tracebacks, and the message behind a decode failure.
6	trace	Every decoded message, position and running per-type tally. The default.

Either the number or the name may be used, and LOG_LEVEL is accepted as an alias for MIN_LOG_LEVEL. Each level includes everything above it in the table.

The default is 6 so that upgrading changes nothing. MIN_LOG_LEVEL=4 is the useful setting for a normal deployment: it keeps startup and connection reporting, plus anything that goes wrong, and drops the per-message output. Measured against a corpus of 4148 real messages, that reduces the log from 22254 lines to 30.

The log level has no effect on the SBS/Basestation messages the container produces, nor on the files written when LOG_FILE is set.

Docker Compose

services:
  acars2pos:
    container_name: acars2pos
    hostname: acars2pos
    image: ghcr.io/rpatel3001/docker-acars2pos
    restart: always
    environment:
      - JSON_IN=acars_router:15550;acars_router:15555;acars_router:15556
      - SBS_OUT=tar1090acars:12000
      - MIN_LOG_LEVEL=4
      - LOG_RAW=true
#      - LOG_FILE=true
      - MAX_DIST=201
      - LAT=aa.bb
      - LON=-xx.yy
#      - SEND_ALL=true