func uploadArtifactToS3(bucket *s3.Bucket, artifactName string, artifactSize int64, contentReader io.ReadSeeker) error {
attempts := 0
for {
attempts++
// Rewind Seeker to beginning, required if we had already read a few bytes from it before.
if _, err := contentReader.Seek(0, os.SEEK_SET); err != nil {
return err
}
if err := bucket.PutReader(artifactName, contentReader, artifactSize, "binary/octet-stream", s3.PublicRead); err != nil {
if attempts < MaxUploadAttempts {
log.Printf("[Attempt %d/%d] Error uploading to S3: %s", attempts, MaxUploadAttempts, err)
continue
}
return fmt.Errorf("Error uploading to S3: %s", err)
}
bytesUploadedCounter.Add(artifactSize)
return nil
}
return nil // This should never happen - only here to satisfy the compiler
}
func PutArtifact(artifact *model.Artifact, db database.Database, bucket *s3.Bucket, req PutArtifactReq) error {
if artifact.State != model.WAITING_FOR_UPLOAD {
return fmt.Errorf("Expected artifact to be in state WAITING_FOR_UPLOAD: %s", artifact.State)
}
// New file being inserted into DB.
// Mark status change to UPLOADING and start uploading to S3.
//
// First, verify that the size of the content being uploaded matches our expected size.
var fileSize int64
var err error
if req.ContentLength != "" {
fileSize, err = strconv.ParseInt(req.ContentLength, 10, 64) // string, base, bits
// This should never happen if a sane HTTP client is used. Nonetheless ...
if err != nil {
return fmt.Errorf("Invalid Content-Length specified")
}
} else {
// This too should never happen if a sane HTTP client is used. Nonetheless ...
return fmt.Errorf("Content-Length not specified")
}
if fileSize != artifact.Size {
return fmt.Errorf("Content length %d does not match expected file size %d", fileSize, artifact.Size)
}
// XXX Do we need to commit here or is this handled transparently?
artifact.State = model.UPLOADING
if err := db.UpdateArtifact(artifact); err != nil {
return err
}
cleanupAndReturn := func(err error) error {
// TODO: Is there a better way to detect and handle errors?
// Use a channel to signify upload completion. In defer, check if the channel is empty. If
// yes, mark error. Else ignore.
if err != nil {
// TODO: s/ERROR/WAITING_FOR_UPLOAD/ ?
log.Printf("Error uploading to S3: %s\n", err)
artifact.State = model.ERROR
err2 := db.UpdateArtifact(artifact)
if err2 != nil {
log.Printf("Error while handling error: %s", err2.Error())
}
return err
}
return nil
}
fileName := artifact.DefaultS3URL()
if err := bucket.PutReader(fileName, req.Body, artifact.Size, "binary/octet-stream", s3.PublicRead); err != nil {
return cleanupAndReturn(fmt.Errorf("Error uploading to S3: %s", err))
}
artifact.State = model.UPLOADED
artifact.S3URL = fileName
if err := db.UpdateArtifact(artifact); err != nil {
return err
}
return nil
}
// Merges all of the individual chunks into a single object and stores it on s3.
// The log chunks are stored in the database, while the object is uploaded to s3.
func MergeLogChunks(artifact *model.Artifact, db database.Database, s3bucket *s3.Bucket) error {
switch artifact.State {
case model.APPEND_COMPLETE:
// TODO: Reimplement using GorpDatabase
// If the file is empty, don't bother creating an object on S3.
if artifact.Size == 0 {
artifact.State = model.CLOSED_WITHOUT_DATA
artifact.S3URL = ""
// Conversion between *DatabaseEror and error is tricky. If we don't do this, a nil
// *DatabaseError can become a non-nil error.
return db.UpdateArtifact(artifact).GetError()
}
// XXX Do we need to commit here or is this handled transparently?
artifact.State = model.UPLOADING
if err := db.UpdateArtifact(artifact); err != nil {
return err
}
logChunks, err := db.ListLogChunksInArtifact(artifact.Id)
if err != nil {
return err
}
r, w := io.Pipe()
errChan := make(chan error)
uploadCompleteChan := make(chan bool)
fileName := artifact.DefaultS3URL()
// Asynchronously upload the object to s3 while reading from the r, w
// pipe. Thus anything written to "w" will be sent to S3.
go func() {
defer close(errChan)
defer close(uploadCompleteChan)
defer r.Close()
if err := s3bucket.PutReader(fileName, r, artifact.Size, "binary/octet-stream", s3.PublicRead); err != nil {
errChan <- fmt.Errorf("Error uploading to S3: %s", err)
return
}
uploadCompleteChan <- true
}()
for _, logChunk := range logChunks {
w.Write([]byte(logChunk.Content))
}
w.Close()
// Wait either for S3 upload to complete or for it to fail with an error.
// XXX This is a long operation and should probably be asynchronous from the
// actual HTTP request, and the client should poll to check when its uploaded.
select {
case _ = <-uploadCompleteChan:
artifact.State = model.UPLOADED
artifact.S3URL = fileName
if err := db.UpdateArtifact(artifact); err != nil {
return err
}
// From this point onwards, we will not send back any errors back to the user. If we are
// unable to delete logchunks, we log it to Sentry instead.
if n, err := db.DeleteLogChunksForArtifact(artifact.Id); err != nil {
// TODO: Send this error to Sentry
log.Printf("Error deleting logchunks for artifact %d: %v\n", artifact.Id, err)
return nil
} else if n != int64(len(logChunks)) {
// TODO: Send this error to Sentry
log.Printf("Mismatch in number of logchunks while deleting logchunks for artifact %d:"+
"Expected: %d Actual: %d\n", artifact.Id, len(logChunks), n)
}
return nil
case err := <-errChan:
return err
}
case model.WAITING_FOR_UPLOAD:
fallthrough
case model.ERROR:
fallthrough
case model.APPENDING:
fallthrough
case model.UPLOADED:
fallthrough
case model.UPLOADING:
return fmt.Errorf("Artifact can only be merged when in APPEND_COMPLETE state, but state is %s", artifact.State)
default:
return fmt.Errorf("Illegal artifact state! State code is %d", artifact.State)
}
}