private void detectText()

in functions/ocr/ocr-process-image/src/main/java/functions/OcrProcessImage.java [83:159]
60 lines of code
9 McCabe index (conditional complexity)

  private void detectText(String bucket, String filename) {
    logger.info("Looking for text in image " + filename);

    List<AnnotateImageRequest> visionRequests = new ArrayList<>();
    String gcsPath = String.format("gs://%s/%s", bucket, filename);

    ImageSource imgSource = ImageSource.newBuilder().setGcsImageUri(gcsPath).build();
    Image img = Image.newBuilder().setSource(imgSource).build();

    Feature textFeature = Feature.newBuilder().setType(Feature.Type.TEXT_DETECTION).build();
    AnnotateImageRequest visionRequest =
        AnnotateImageRequest.newBuilder().addFeatures(textFeature).setImage(img).build();
    visionRequests.add(visionRequest);

    // Detect text in an image using the Cloud Vision API
    AnnotateImageResponse visionResponse;
    try (ImageAnnotatorClient client = ImageAnnotatorClient.create()) {
      visionResponse = client.batchAnnotateImages(visionRequests).getResponses(0);
      if (visionResponse == null || !visionResponse.hasFullTextAnnotation()) {
        logger.info(String.format("Image %s contains no text", filename));
        return;
      }

      if (visionResponse.hasError()) {
        // Log error
        logger.log(
            Level.SEVERE, "Error in vision API call: " + visionResponse.getError().getMessage());
        return;
      }
    } catch (IOException e) {
      // Log error (since IOException cannot be thrown by a Cloud Function)
      logger.log(Level.SEVERE, "Error detecting text: " + e.getMessage(), e);
      return;
    }

    String text = visionResponse.getFullTextAnnotation().getText();
    logger.info("Extracted text from image: " + text);

    // Detect language using the Cloud Translation API
    DetectLanguageRequest languageRequest =
        DetectLanguageRequest.newBuilder()
            .setParent(LOCATION_NAME)
            .setMimeType("text/plain")
            .setContent(text)
            .build();
    DetectLanguageResponse languageResponse;
    try (TranslationServiceClient client = TranslationServiceClient.create()) {
      languageResponse = client.detectLanguage(languageRequest);
    } catch (IOException e) {
      // Log error (since IOException cannot be thrown by a function)
      logger.log(Level.SEVERE, "Error detecting language: " + e.getMessage(), e);
      return;
    }

    if (languageResponse.getLanguagesCount() == 0) {
      logger.info("No languages were detected for text: " + text);
      return;
    }

    String languageCode = languageResponse.getLanguages(0).getLanguageCode();
    logger.info(String.format("Detected language %s for file %s", languageCode, filename));

    // Send a Pub/Sub translation request for every language we're going to translate to
    for (String targetLanguage : TO_LANGS) {
      logger.info("Sending translation request for language " + targetLanguage);
      OcrTranslateApiMessage message = new OcrTranslateApiMessage(text, filename, targetLanguage);
      ByteString byteStr = ByteString.copyFrom(message.toPubsubData());
      PubsubMessage pubsubApiMessage = PubsubMessage.newBuilder().setData(byteStr).build();
      try {
        publisher.publish(pubsubApiMessage).get();
      } catch (InterruptedException | ExecutionException e) {
        // Log error
        logger.log(Level.SEVERE, "Error publishing translation request: " + e.getMessage(), e);
        return;
      }
    }
  }