55 lines
1.5 KiB
Markdown
55 lines
1.5 KiB
Markdown
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# Web Server
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There is one web server,
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which provides static content,
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and a single entrypoint for dynamic state information.
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The static content is some HTML and JavaScript,
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which the browser runs to pull the dynamic state,
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and update the page with current status of everything.
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# Workers
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There are at least two Workers:
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a Reader and an Encoder.
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Each Worker runs in its own thread,
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and can do its job without interfering with another Worker.
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## Readers
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Readers monitor a device for media.
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Right now, those devices are always CD-ROM drives.
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As soon as media is inserted,
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a MediaHandler is created to scan and then copy it.
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## Encoders
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Encoders wait for jobs to show up,
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and then they re-invoke a MediaHandler to encode everything in that job.
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# MediaHandlers
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MediaHandlers have a work directory,
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where they store all their stuff.
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They have the following stages of execution:
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1. *scan* the media to figure out its title, list of tracks, and other metadata
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2. *copy* the media to the work directory
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3. *encode* the work directory into the desired format (eg. MP3, MKV)
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4. *clean* the work directory
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Before each step,
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state is read out of the work directory.
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During each step,
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a MediaHandler continually updates its Worker with a completion percentage.
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This is passed up to the Web Server's dynamic state.
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After each step,
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a MediaHandler updates its state,
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which is stored on disk.
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The only way to communicate state between execution stages is by writing to disk.
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This provides some tolerance of job interruption, power loss, etc.
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