diff options
Diffstat (limited to 'bridge/helper')
-rw-r--r-- | bridge/helper/helper.go | 51 |
1 files changed, 50 insertions, 1 deletions
diff --git a/bridge/helper/helper.go b/bridge/helper/helper.go index 41244766..2b449e14 100644 --- a/bridge/helper/helper.go +++ b/bridge/helper/helper.go @@ -5,7 +5,10 @@ import ( "fmt" "image/png" "io" + "io/ioutil" "net/http" + "os" + "os/exec" "regexp" "strings" "time" @@ -192,7 +195,7 @@ func ParseMarkdown(input string) string { return res } -// ConvertWebPToPNG convert input data (which should be WebP format to PNG format) +// ConvertWebPToPNG converts input data (which should be WebP format) to PNG format func ConvertWebPToPNG(data *[]byte) error { r := bytes.NewReader(*data) m, err := webp.Decode(r) @@ -207,3 +210,49 @@ func ConvertWebPToPNG(data *[]byte) error { *data = w.Bytes() return nil } + +// CanConvertTgsToX Checks whether the external command necessary for ConvertTgsToX works. +func CanConvertTgsToX() error { + // We depend on the fact that `lottie_convert.py --help` has exit status 0. + // Hyrum's Law predicted this, and Murphy's Law predicts that this will break eventually. + // However, there is no alternative like `lottie_convert.py --is-properly-installed` + cmd := exec.Command("lottie_convert.py", "--help") + return cmd.Run() +} + +// ConvertTgsToWebP convert input data (which should be tgs format) to WebP format +// This relies on an external command, which is ugly, but works. +func ConvertTgsToX(data *[]byte, outputFormat string, logger *logrus.Entry) error { + // lottie can't handle input from a pipe, so write to a temporary file: + tmpFile, err := ioutil.TempFile(os.TempDir(), "matterbridge-lottie-*.tgs") + if err != nil { + return err + } + tmpFileName := tmpFile.Name() + defer func() { + if removeErr := os.Remove(tmpFileName); removeErr != nil { + logger.Errorf("Could not delete temporary file %s: %v", tmpFileName, removeErr) + } + }() + + if _, writeErr := tmpFile.Write(*data); writeErr != nil { + return writeErr + } + // Must close before calling lottie to avoid data races: + if closeErr := tmpFile.Close(); closeErr != nil { + return closeErr + } + + // Call lottie to transform: + cmd := exec.Command("lottie_convert.py", "--input-format", "lottie", "--output-format", outputFormat, tmpFileName, "/dev/stdout") + cmd.Stderr = nil + // NB: lottie writes progress into to stderr in all cases. + stdout, stderr := cmd.Output() + if stderr != nil { + // 'stderr' already contains some parts of Stderr, because it was set to 'nil'. + return stderr + } + + *data = stdout + return nil +} |