Update streamPrediction to do non-blocking send to errChan (#84)

* Non-blocking send to errChan

* Create sendError helper method

Author: mattt

stream.go

@@ -97,13 +97,20 @@ func (e *SSEEvent) String() string {
 	}
 }
 
+func (r *Client) sendError(err error, errChan chan error) {
+	select {
+	case errChan <- err:
+	default:
+	}
+}
+
 func (r *Client) Stream(ctx context.Context, identifier string, input PredictionInput, webhook *Webhook) (<-chan SSEEvent, <-chan error) {
 	sseChan := make(chan SSEEvent, 64)
 	errChan := make(chan error, 64)
 
 	id, err := ParseIdentifier(identifier)
 	if err != nil {
-		errChan <- err
+		r.sendError(err, errChan)
 		return sseChan, errChan
 	}
 
@@ -115,7 +122,7 @@ func (r *Client) Stream(ctx context.Context, identifier string, input Prediction
 	}
 
 	if err != nil {
-		errChan <- err
+		r.sendError(err, errChan)
 		return sseChan, errChan
 	}
 
@@ -136,16 +143,13 @@ func (r *Client) StreamPrediction(ctx context.Context, prediction *Prediction) (
 func (r *Client) streamPrediction(ctx context.Context, prediction *Prediction, lastEvent *SSEEvent, sseChan chan SSEEvent, errChan chan error) {
 	url := prediction.URLs["stream"]
 	if url == "" {
-		errChan <- errors.New("streaming not supported or not enabled for this prediction")
+		r.sendError(errors.New("streaming not supported or not enabled for this prediction"), errChan)
 		return
 	}
 
 	req, err := http.NewRequestWithContext(ctx, http.MethodGet, url, nil)
 	if err != nil {
-		select {
-		case errChan <- fmt.Errorf("failed to create request: %w", err):
-		default:
-		}
+		r.sendError(fmt.Errorf("failed to create request: %w", err), errChan)
 		return
 	}
 	req.Header.Set("Accept", "text/event-stream")
@@ -163,18 +167,12 @@ func (r *Client) streamPrediction(ctx context.Context, prediction *Prediction, l
 		} else {
 			defer resp.Body.Close()
 		}
-		select {
-		case errChan <- fmt.Errorf("failed to send request: %w", err):
-		default:
-		}
+		r.sendError(fmt.Errorf("failed to send request: %w", err), errChan)
 		return
 	}
 
 	if resp.StatusCode != http.StatusOK {
-		select {
-		case errChan <- fmt.Errorf("received invalid status code: %d", resp.StatusCode):
-		default:
-		}
+		r.sendError(fmt.Errorf("received invalid status code: %d", resp.StatusCode), errChan)
 		return
 	}
 
@@ -229,10 +227,7 @@ func (r *Client) streamPrediction(ctx context.Context, prediction *Prediction, l
 
 					event, err := decodeSSEEvent(b)
 					if err != nil {
-						select {
-						case errChan <- err:
-						default:
-						}
+						r.sendError(err, errChan)
 						continue
 					}
 
@@ -269,10 +264,7 @@ func (r *Client) streamPrediction(ctx context.Context, prediction *Prediction, l
 			}
 
 			if !errors.Is(err, context.Canceled) {
-				select {
-				case errChan <- err:
-				default:
-				}
+				r.sendError(err, errChan)
 			}
 		}