Improve error handling and resource management in streamPrediction (#79)

* Move up deferred closing of response body

* Return context error instead of nil

* Send to line channel in select with context check

* Refactor final goroutine in streamPrediction

Author: mattt

stream.go

@@ -169,20 +169,24 @@ func (r *Client) streamPrediction(ctx context.Context, prediction *Prediction, l
 
 	g.Go(func() error {
 		defer close(lineChan)
+		defer resp.Body.Close()
 
 		for {
 			select {
 			case <-ctx.Done():
-				return nil
+				return ctx.Err()
 			case <-done:
 				return nil
 			default:
 				line, err := reader.ReadBytes('\n')
 				if err != nil {
-					defer resp.Body.Close()
 					return err
 				}
-				lineChan <- line
+				select {
+				case lineChan <- line:
+				case <-ctx.Done():
+					return ctx.Err()
+				}
 			}
 		}
 	})
@@ -223,30 +227,27 @@ func (r *Client) streamPrediction(ctx context.Context, prediction *Prediction, l
 	}()
 
 	go func() {
+		err := g.Wait()
+
 		defer close(sseChan)
 		defer close(errChan)
 
-		for {
-			select {
-			case <-ctx.Done():
-				return
-			case <-done:
+		if err != nil {
+			if errors.Is(err, io.EOF) {
+				// Attempt to reconnect if the connection was closed before the stream was done
+				r.streamPrediction(ctx, prediction, lastEvent, sseChan, errChan)
 				return
-			default:
-				err := g.Wait()
-				if err != nil {
-					if err == io.EOF {
-						// Attempt to reconnect if the connection was closed before the stream was done
-						r.streamPrediction(ctx, prediction, lastEvent, sseChan, errChan)
-						continue
-					}
+			}
 
-					if errors.Is(err, context.Canceled) {
-						return
-					}
+			if errors.Is(err, context.Canceled) {
+				// Context was canceled, simply return
+				return
+			}
 
-					errChan <- err
-				}
+			select {
+			case errChan <- err:
+			default:
+				// errChan is full or closed
 			}
 		}
 	}()