When using http for output, the output url cannot have $ character

[duggaraju]

System info

Operating System: All OS
Shaka Packager Version: 2.6.1

Issue and steps to reproduce the problem

packager in=test.mp4,stream=video,out=http://localhost:8080/$test/video.mp4
Packager Command:

Extra steps to reproduce the problem?
(1) create a small web server (I tested with a nodejs sample that can accept put and write to a file)
(2) run the packager command to output to http.

What is the expected result?
The command should succeed
What happens instead?
[0707/153327:ERROR:packager_main.cc(549)] Failed to initialize packager: 3 (INVALID_ARGUMENT): In segment templates $Number$ or $Time$ should exist.
<Please attach the input files or email to shaka-packager-issues@google.com.>

When writing to a single file the validator still expects $Time or $Number and escaping of $$ doesn't work.

[cosmin]

I think the presence of $ is triggering the segment template validation. This comment in muxer.cc seems relevant

https://github.com/shaka-project/shaka-packager/blob/main/packager/media/base/muxer.cc#L23

// "$" is only allowed if the output file name is a template

[xavierlaffargue]

Indeed, @duggaraju you can use $$ to escape $ : (https://shaka-project.github.io/shaka-packager/html/tutorials/hls.html#segment-template-formatting)

packager in=test.mp4,stream=video,out=http://localhost:8080/$$test/video.mp4