[feature] support processing of (many) more media types (#3090)

* initial work replacing our media decoding / encoding pipeline with ffprobe + ffmpeg

* specify the video codec to use when generating static image from emoji

* update go-storage library (fixes incompatibility after updating go-iotools)

* maintain image aspect ratio when generating a thumbnail for it

* update readme to show go-ffmpreg

* fix a bunch of media tests, move filesize checking to callers of media manager for more flexibility

* remove extra debug from error message

* fix up incorrect function signatures

* update PutFile to just use regular file copy, as changes are file is on separate partition

* fix remaining tests, remove some unneeded tests now we're working with ffmpeg/ffprobe

* update more tests, add more code comments

* add utilities to generate processed emoji / media outputs

* fix remaining tests

* add test for opus media file, add license header to utility cmds

* limit the number of concurrently available ffmpeg / ffprobe instances

* reduce number of instances

* further reduce number of instances

* fix envparsing test with configuration variables

* update docs and configuration with new media-{local,remote}-max-size variables

1 files changed, 0 insertions, 63 deletions

diff --git a/vendor/github.com/dsoprea/go-utility/v2/filesystem/readseeker_to_readerat.go b/vendor/github.com/dsoprea/go-utility/v2/filesystem/readseeker_to_readerat.go
deleted file mode 100644
index 3f3ec44dd..000000000
--- a/vendor/github.com/dsoprea/go-utility/v2/filesystem/readseeker_to_readerat.go
+++ /dev/null
@@ -1,63 +0,0 @@
-package rifs
-
-import (
-	"io"
-
-	"github.com/dsoprea/go-logging"
-)
-
-// ReadSeekerToReaderAt is a wrapper that allows a ReadSeeker to masquerade as a
-// ReaderAt.
-type ReadSeekerToReaderAt struct {
-	rs io.ReadSeeker
-}
-
-// NewReadSeekerToReaderAt returns a new ReadSeekerToReaderAt instance.
-func NewReadSeekerToReaderAt(rs io.ReadSeeker) *ReadSeekerToReaderAt {
-	return &ReadSeekerToReaderAt{
-		rs: rs,
-	}
-}
-
-// ReadAt is a wrapper that satisfies the ReaderAt interface.
-//
-// Note that a requirement of ReadAt is that it doesn't have an effect on the
-// offset in the underlying resource as well as that concurrent calls can be
-// made to it. Since we're capturing the current offset in the underlying
-// resource and then seeking back to it before returning, it is the
-// responsibility of the caller to serialize (i.e. use a mutex with) these
-// requests in order to eliminate race-conditions in the parallel-usage
-// scenario.
-//
-// Note also that, since ReadAt() is going to be called on a particular
-// instance, that instance is going to internalize a file resource, that file-
-// resource is provided by the OS, and [most] OSs are only gonna support one
-// file-position per resource, locking is already going to be a necessary
-// internal semantic of a ReaderAt implementation.
-func (rstra *ReadSeekerToReaderAt) ReadAt(p []byte, offset int64) (n int, err error) {
-	defer func() {
-		if state := recover(); state != nil {
-			err = log.Wrap(state.(error))
-		}
-	}()
-
-	originalOffset, err := rstra.rs.Seek(0, io.SeekCurrent)
-	log.PanicIf(err)
-
-	defer func() {
-		_, err := rstra.rs.Seek(originalOffset, io.SeekStart)
-		log.PanicIf(err)
-	}()
-
-	_, err = rstra.rs.Seek(offset, io.SeekStart)
-	log.PanicIf(err)
-
-	// Note that all errors will be wrapped, here. The usage of this method is
-	// such that typically no specific errors would be expected as part of
-	// normal operation (in which case we'd check for those first and return
-	// them directly).
-	n, err = io.ReadFull(rstra.rs, p)
-	log.PanicIf(err)
-
-	return n, nil
-}