package store import ( "bytes" "io" "io/ioutil" "net" "net/http" "sync" "time" "github.com/lbryio/reflector.go/internal/metrics" "github.com/lbryio/reflector.go/shared" "github.com/lbryio/lbry.go/v2/extras/errors" "github.com/lbryio/lbry.go/v2/stream" ) // HttpStore is a store that works on top of the HTTP protocol type HttpStore struct { upstream string httpClient *http.Client edgeToken string } func NewHttpStore(upstream, edgeToken string) *HttpStore { return &HttpStore{ upstream: "http://" + upstream, httpClient: getClient(), edgeToken: edgeToken, } } const nameHttp = "http" func (n *HttpStore) Name() string { return nameHttp } func (n *HttpStore) Has(hash string) (bool, error) { url := n.upstream + "/blob?hash=" + hash req, err := http.NewRequest("HEAD", url, nil) if err != nil { return false, errors.Err(err) } res, err := n.httpClient.Do(req) if err != nil { return false, errors.Err(err) } defer res.Body.Close() if res.StatusCode == http.StatusNotFound { return false, nil } if res.StatusCode == http.StatusNoContent { return true, nil } var body []byte if res.Body != nil { body, _ = ioutil.ReadAll(res.Body) } return false, errors.Err("upstream error. Status code: %d (%s)", res.StatusCode, string(body)) } func (n *HttpStore) Get(hash string) (stream.Blob, shared.BlobTrace, error) { start := time.Now() url := n.upstream + "/blob?hash=" + hash if n.edgeToken != "" { url += "&edge_token=" + n.edgeToken } req, err := http.NewRequest("GET", url, nil) if err != nil { return nil, shared.NewBlobTrace(time.Since(start), n.Name()), errors.Err(err) } res, err := n.httpClient.Do(req) if err != nil { return nil, shared.NewBlobTrace(time.Since(start), n.Name()), errors.Err(err) } defer res.Body.Close() tmp := getBuffer() defer putBuffer(tmp) serialized := res.Header.Get("Via") trace := shared.NewBlobTrace(time.Since(start), n.Name()) if serialized != "" { parsedTrace, err := shared.Deserialize(serialized) if err != nil { return nil, shared.NewBlobTrace(time.Since(start), n.Name()), err } trace = *parsedTrace } if res.StatusCode == http.StatusNotFound { return nil, trace.Stack(time.Since(start), n.Name()), ErrBlobNotFound } if res.StatusCode == http.StatusOK { written, err := io.Copy(tmp, res.Body) if err != nil { return nil, trace.Stack(time.Since(start), n.Name()), errors.Err(err) } blob := make([]byte, written) copy(blob, tmp.Bytes()) metrics.MtrInBytesHttp.Add(float64(len(blob))) return blob, trace.Stack(time.Since(start), n.Name()), nil } var body []byte if res.Body != nil { body, _ = ioutil.ReadAll(res.Body) } return nil, trace.Stack(time.Since(start), n.Name()), errors.Err("upstream error. Status code: %d (%s)", res.StatusCode, string(body)) } func (n *HttpStore) Put(string, stream.Blob) error { return shared.ErrNotImplemented } func (n *HttpStore) PutSD(string, stream.Blob) error { return shared.ErrNotImplemented } func (n *HttpStore) Delete(string) error { return shared.ErrNotImplemented } func (n *HttpStore) Shutdown() {} // buffer pool to reduce GC // https://www.captaincodeman.com/2017/06/02/golang-buffer-pool-gotcha var buffers = sync.Pool{ // New is called when a new instance is needed New: func() interface{} { buf := make([]byte, 0, stream.MaxBlobSize) return bytes.NewBuffer(buf) }, } // getBuffer fetches a buffer from the pool func getBuffer() *bytes.Buffer { return buffers.Get().(*bytes.Buffer) } // putBuffer returns a buffer to the pool func putBuffer(buf *bytes.Buffer) { buf.Reset() buffers.Put(buf) } // getClient gets an http client that's customized to be more performant when dealing with blobs of 2MB in size (most of our blobs) func getClient() *http.Client { // Customize the Transport to have larger connection pool defaultTransport := &http.Transport{ DialContext: (&net.Dialer{ Timeout: 30 * time.Second, KeepAlive: 30 * time.Second, }).DialContext, ForceAttemptHTTP2: true, MaxIdleConns: 100, IdleConnTimeout: 90 * time.Second, TLSHandshakeTimeout: 10 * time.Second, ExpectContinueTimeout: 1 * time.Second, DisableCompression: true, MaxIdleConnsPerHost: 100, ReadBufferSize: stream.MaxBlobSize + 1024*10, //add an extra few KBs to make sure it fits the extra information } return &http.Client{Transport: defaultTransport} }