7eb5514b65bff95a140749317af2638c65313261
[EVA-2020-02.git] / exec / bkgpslog-plan.org
1 * bkgpslog task list
2 ** DONE Add job control for short buffer length
3 CLOSED: [2020-07-02 Thu 16:04]
4 2020-07-02T14:56Z; bktei> File write operations were bundled into a
5 magicWriteBuffer function that is called then detached from the script
6 shell (job control), but the detached job is not tracked by the main
7 script. A problem may arise if two instances of magicWriteBuffer
8 attempt to write to the same tar simultaneously. Two instances of
9 magicWriteBuffer may exist if the buffer length is low (ex: 1 second);
10 the default buffer length of 60 seconds should reduce the probability
11 of a collision but it should be possible for the main script to track
12 the process ID of a magicWriteBuffer() as soon as it detaches and then
13 checking (via ~$!~ as described [[https://bashitout.com/2013/05/18/Ampersands-on-the-command-line.html][here]]) that the process is still alive.
14 2020-07-02T15:23Z; bktei> I found that the Bash ~wait~ built-in can be
15 used to delay processing until a specified job completes. The ~wait~
16 command will pause script execution until all backgrounded processes
17 complete.
18 2020-07-02T16:03Z; bktei> Added ~wait~.
19 * bkgpslog narrative
20 ** Initialize environment
21 *** Init variables
22 **** Save timeStart (YYYYmmddTHHMMSS±zz)
23 *** Define Functions
24 **** Define Debugging functions
25 **** Define Argument Processing function
26 **** Define Main function
27 ** Run Main Function
28 *** Process Arguments
29 *** Set output encryption and compression option strings
30 *** Check that critical apps and dirs are available, displag missing ones.
31 *** Set lifespans of script and buffer
32 *** Init temp working dir ~DIR_TMP~
33 Make temporary dir in tmpfs dir: ~/dev/shm/$(nonce)..bkgpslog/~ (~DIR_TMP~)
34 *** Initialize ~tar~ archive
35 **** Write ~bkgpslog~ version to ~$DIR_TMP/VERSION~
36 **** Create empty ~tar~ archive in ~DIR_OUT~ at ~PATHOUT_TAR~
37
38 Set output file name to:
39 : PATHOUT_TAR="$DIR_OUT/YYYYmmdd..hostname_location.gz.age.tar"
40 Usage: ~iso8601Period $timeStart $timeEnd~
41
42 **** Append ~VERSION~ file to ~PATHOUT_TAR~
43
44 Append ~$DIR_TMP/VERSION~ to ~PATHOUT_TAR~ via ~tar --append~
45
46 *** Read/Write Loop (Record gps data until script lifespan ends)
47 **** Determine output file paths
48 **** Define GPS conversion commands
49 **** Fill Bash variable buffer from ~gpspipe~
50 **** Process bufferBash, save secured chunk set to ~DIR_TMP~
51 **** Append each secured chunk to ~PATHOUT_TAR~
52 : tar --append --directory=DIR_TMP --file=PATHOUT_TAR $(basename PATHOUT_{NMEA,GPX,KML} )
53 **** Remove secured chunk from ~DIR_TMP~