how to callpython function through button in web2py?

Question

I am creating a web2py app; I want a button that can call a Python function available in controller folder in default.py and show the text result.

The function is:

src_path =
"/home/globalstat/web2py/applications/image_resize/controllers/"


def get_string(img_path):

    # Read image with opencv
    img_0 = cv2.imread(img_path)


    # Convert to gray
    img = cv2.cvtColor(img_0, cv2.COLOR_BGR2GRAY)

    # thresh = 127
    # im_bw = cv2.threshold(img, thresh, 255, cv2.THRESH_BINARY)[1]
    # cv2.imwrite('bw_image.png', im_bw)


    # Apply threshold to get image with only black and white
    #img = cv2.adaptiveThreshold(img, 255, cv2.ADAPTIVE_THRESH_GAUSSIAN_C, v2.THRESH_BINARY, 11, 2)

    # Write the image after apply opencv to do some ...
    #cv2.imwrite(src_path + "thres.png", img)
    # Apply dilation and erosion to remove some noise
    kernel = np.ones((1, 1), np.uint8)
    img = cv2.dilate(img, kernel, iterations=1)
    img = cv2.erode(img, kernel, iterations=1)

    cv2.imwrite(src_path + "removednoise.jpg", img)

     # Apply threshold to get image with only gray scaled
     img = cv2.adaptiveThreshold(img, 255, cv2.ADAPTIVE_THRESH_GAUSSIAN_C, cv2.THRESH_BINARY, 11, 2)


    cv2.imwrite(src_path + "thres.jpg", img)


    # Recognize text with tesseract for python
    #img_ref=Image.open(src_path + "removednoise.jpg")
    img_ref=Image.open(src_path + "thres.jpg")

    img_ref.save("test-600.png",doing=(600,600))

    result = pytesseract.image_to_string(img_ref)


    return result

and the code I'm using in view file for button is:

<Button type="button" name ="seeting_button" onclick =
'window.location="{{=URL('default', 'get_string',)}}";'>

How can I pass argument so it displays result?

Answer 1

Try changing

def get_string(img_path):
   img_0 = cv2.imread(img_path)

Into

def get_string():
   img_path = request.args[0]
   img_0 = cv2.imread(img_path)

Any function with parameters inside a controller file is ignored by web2py. Arguments are passed through request.args