Make lottie_convert work on platforms without /dev/stdout (#1424)

Fixes #1423.
This commit is contained in:
Ben Wiederhake 2021-03-20 22:42:41 +01:00 committed by GitHub
parent ee5d9b43b5
commit 0450482e6e
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@ -248,35 +248,52 @@ func CanConvertTgsToX() error {
// This relies on an external command, which is ugly, but works. // This relies on an external command, which is ugly, but works.
func ConvertTgsToX(data *[]byte, outputFormat string, logger *logrus.Entry) error { func ConvertTgsToX(data *[]byte, outputFormat string, logger *logrus.Entry) error {
// lottie can't handle input from a pipe, so write to a temporary file: // lottie can't handle input from a pipe, so write to a temporary file:
tmpFile, err := ioutil.TempFile(os.TempDir(), "matterbridge-lottie-*.tgs") tmpInFile, err := ioutil.TempFile(os.TempDir(), "matterbridge-lottie-input-*.tgs")
if err != nil { if err != nil {
return err return err
} }
tmpFileName := tmpFile.Name() tmpInFileName := tmpInFile.Name()
defer func() { defer func() {
if removeErr := os.Remove(tmpFileName); removeErr != nil { if removeErr := os.Remove(tmpInFileName); removeErr != nil {
logger.Errorf("Could not delete temporary file %s: %v", tmpFileName, removeErr) logger.Errorf("Could not delete temporary (input) file %s: %v", tmpInFileName, removeErr)
}
}()
// lottie can handle writing to a pipe, but there is no way to do that platform-independently.
// "/dev/stdout" won't work on Windows, and "-" upsets Cairo for some reason. So we need another file:
tmpOutFile, err := ioutil.TempFile(os.TempDir(), "matterbridge-lottie-output-*.data")
if err != nil {
return err
}
tmpOutFileName := tmpOutFile.Name()
defer func() {
if removeErr := os.Remove(tmpOutFileName); removeErr != nil {
logger.Errorf("Could not delete temporary (output) file %s: %v", tmpOutFileName, removeErr)
} }
}() }()
if _, writeErr := tmpFile.Write(*data); writeErr != nil { if _, writeErr := tmpInFile.Write(*data); writeErr != nil {
return writeErr return writeErr
} }
// Must close before calling lottie to avoid data races: // Must close before calling lottie to avoid data races:
if closeErr := tmpFile.Close(); closeErr != nil { if closeErr := tmpInFile.Close(); closeErr != nil {
return closeErr return closeErr
} }
// Call lottie to transform: // Call lottie to transform:
cmd := exec.Command("lottie_convert.py", "--input-format", "lottie", "--output-format", outputFormat, tmpFileName, "/dev/stdout") cmd := exec.Command("lottie_convert.py", "--input-format", "lottie", "--output-format", outputFormat, tmpInFileName, tmpOutFileName)
cmd.Stdout = nil
cmd.Stderr = nil cmd.Stderr = nil
// NB: lottie writes progress into to stderr in all cases. // NB: lottie writes progress into to stderr in all cases.
stdout, stderr := cmd.Output() _, stderr := cmd.Output()
if stderr != nil { if stderr != nil {
// 'stderr' already contains some parts of Stderr, because it was set to 'nil'. // 'stderr' already contains some parts of Stderr, because it was set to 'nil'.
return stderr return stderr
} }
dataContents, err := ioutil.ReadFile(tmpOutFileName)
if err != nil {
return err
}
*data = stdout *data = dataContents
return nil return nil
} }