DownloadBlocks starts a goroutine to download blocks from the given peer, starting at the given height and incrementing from there. It will re-attempt downloads for the next block in the network until it is available. It returns two channels, one for reading blocks and the other for reading errors.
(ctx context.Context, peer *rpc.Client, height uint64)
| 91 | // reading from both. DownloadBlocks will continue even if it encounters errors, |
| 92 | // until its context is done. |
| 93 | func DownloadBlocks(ctx context.Context, peer *rpc.Client, height uint64) (chan *legacy.Block, chan error) { |
| 94 | blockch := make(chan *legacy.Block) |
| 95 | errch := make(chan error) |
| 96 | go func() { |
| 97 | var nfailures uint // for backoff |
| 98 | var ntimeouts uint // for backoff |
| 99 | for { |
| 100 | select { |
| 101 | case <-ctx.Done(): |
| 102 | close(blockch) |
| 103 | close(errch) |
| 104 | return |
| 105 | default: |
| 106 | block, err := getBlock(ctx, peer, height, timeoutBackoffDur(ntimeouts)) |
| 107 | if err != nil { |
| 108 | errch <- err |
| 109 | nfailures++ |
| 110 | time.Sleep(backoffDur(nfailures)) |
| 111 | continue |
| 112 | } |
| 113 | if block == nil { |
| 114 | // Request time out. There might not have been any blocks published, |
| 115 | // or there was a network error or it just took too long to process the |
| 116 | // request. |
| 117 | ntimeouts++ |
| 118 | continue |
| 119 | } |
| 120 | |
| 121 | blockch <- block |
| 122 | ntimeouts, nfailures = 0, 0 |
| 123 | height++ |
| 124 | } |
| 125 | } |
| 126 | }() |
| 127 | return blockch, errch |
| 128 | } |
| 129 | |
| 130 | func pollGeneratorHeight(ctx context.Context, peer *rpc.Client) { |
| 131 | updateGeneratorHeight(ctx, peer) |
no test coverage detected