AP-515: add 4.9.6 image for cross-platform testing

[anarchivist]

This switches Wowza Streaming Engine/Manager from our custom startup scripts to using their default supervisord based setup. In general, this greatly simplifies our custom image.

• Build from wowzamedia/wowza-streaming-engine-linux:4.9.6.
• Auto install platform-specific version of OpenJDK 21 and update necessary log4j classes to their appropriate versions.
• Wrap Python testing scripts in a virtual environment.
• Readd arm64 to the build matrix.
• Add healthcheck to the compose file for the API endpoint.
• Turn Wowza's supervisord config files into templates so we can override them with our preferred settings.
• Automatically forward supervisord's child process logs to STDOUT and STDERR.

[anarchivist]

This appears to duplicate the logs to stdout (i.e., they're sent twice for the supervisord's process logs):

$ docker compose logs
WARN[0000] The "CI" variable is not set. Defaulting to a blank string.
app-1  | docker-entrypoint.sh running
app-1  | enable-documentation-server.sh running
app-1  | Enabling documentation server
app-1  | Allowing unauthenticated access to documentation server
app-1  | Swagger/OpenAPI documentation server available at http://localhost:8089/api-docs
app-1  | secrets.sh running
app-1  | secrets.sh complete
app-1  | Invoking Wowza's /sbin/entrypoint.sh
app-1  | 2025-12-02 00:07:21,887 INFO Included extra file "/etc/supervisor/conf.d/WowzaStreamingEngine.conf" during parsing
app-1  | 2025-12-02 00:07:21,887 INFO Included extra file "/etc/supervisor/conf.d/WowzaStreamingEngine.conf" during parsing
app-1  | 2025-12-02 00:07:21,887 INFO Included extra file "/etc/supervisor/conf.d/WowzaStreamingEngineManager.conf" during parsing
app-1  | 2025-12-02 00:07:21,887 INFO Included extra file "/etc/supervisor/conf.d/WowzaStreamingEngineManager.conf" during parsing
app-1  | 2025-12-02 00:07:21,887 INFO Set uid to user 40041 succeeded
app-1  | 2025-12-02 00:07:21,887 INFO Set uid to user 40041 succeeded
app-1  | 2025-12-02 00:07:21,892 INFO RPC interface 'supervisor' initialized
app-1  | 2025-12-02 00:07:21,892 INFO RPC interface 'supervisor' initialized
app-1  | 2025-12-02 00:07:21,892 CRIT Server 'unix_http_server' running without any HTTP authentication checking
app-1  | 2025-12-02 00:07:21,892 CRIT Server 'unix_http_server' running without any HTTP authentication checking
app-1  | 2025-12-02 00:07:21,893 INFO supervisord started with pid 1
app-1  | 2025-12-02 00:07:21,893 INFO supervisord started with pid 1
app-1  | 2025-12-02 00:07:22,906 INFO spawned: 'WowzaStreamingEngine' with pid 19
app-1  | 2025-12-02 00:07:22,906 INFO spawned: 'WowzaStreamingEngine' with pid 19
app-1  | 2025-12-02 00:07:22,912 INFO spawned: 'WowzaStreamingEngineManager' with pid 20
app-1  | 2025-12-02 00:07:22,912 INFO spawned: 'WowzaStreamingEngineManager' with pid 20
app-1  | INFO: Main.main: root: /usr/local/WowzaStreamingEngine/manager
app-1  | INFO: Main.main: loadApplication: launch.Application
app-1  | 2025-12-02 00:07:24,512 INFO success: WowzaStreamingEngine entered RUNNING state, process has stayed up for > than 1 seconds (startsecs)
app-1  | 2025-12-02 00:07:24,512 INFO success: WowzaStreamingEngine entered RUNNING state, process has stayed up for > than 1 seconds (startsecs)
app-1  | 2025-12-02 00:07:24,512 INFO success: WowzaStreamingEngineManager entered RUNNING state, process has stayed up for > than 1 seconds (startsecs)
app-1  | 2025-12-02 00:07:24,512 INFO success: WowzaStreamingEngineManager entered RUNNING state, process has stayed up for > than 1 seconds (startsecs)

[danschmidt5189]

Docker recommends a few modifications to this, most notably setting supervisord's logfile to /dev/null:

[supervisord]
nodaemon=true
logfile=/dev/null
logfile_maxbytes=0

[program:app]
stdout_logfile=/dev/fd/1
stdout_logfile_maxbytes=0
redirect_stderr=true

I'm not sure why they write program logs to /dev/fd/1 versus the more familar /dev/stdout, when as far as I can tell they're equivalent. From this image:

# ls -l /dev/stdout
lrwxrwxrwx 1 root root 15 Dec  2 07:56 /dev/stdout -> /proc/self/fd/1

# ls -l /proc/self/fd/1
lrwx------ 1 root root 64 Dec  2 07:56 /proc/self/fd/1 -> /dev/pts/0

# ls -l /dev/fd/1
lrwx------ 1 root root 64 Dec  2 07:56 /dev/fd/1 -> /dev/pts/0

[anarchivist]

fixed in 7bcaad7. nodaemon=true is unnecessary as the Wowza image entrypoint that our entrypoint script execs into calls supervisord -n.

[danschmidt5189]

Mentioned it in our review this morning but worth asking again here: is there a reason not to include this in the Dockerfile? That would make it easier to configure across environments, and it can still be disabled via healthcheck: { disable: true}.

[anarchivist]

fixed in 7bcaad7.

[danschmidt5189]

I think we ought to sort out the logging issue (see the link in my comment for potential guidance). The healthcheck is a minor complaint and IMO not a blocker, but I think it would be an improvement over including that in the Compose file—worth considering.

[danschmidt5189]

Looks good! Now to poke at it on staging. 🚢