python - POST request results in "internal server error", most of the times but not all (!?) -

edit:

tl;dr:

how post image using python request flask app can use opencv manipulate it?

long version of question , stuff i've tried out:

i trying post image 1 python flask app another. problem facing seems work sometimes, not.

app receives data:

@app.route("/post", methods=['get', 'post']) def post():     print "in post"     req = request.files['file']     #    req = open('pug.jpg', 'r+b')     arr = np.asarray(bytearray(req.read()), dtype=np.uint8)     img = cv2.imdecode(arr,-1) # 'load is'     print img     cv2.imwrite('result.png',img)     return "hello" 

app sends data:

def hello():     url = 'http://ip_address/post'     #this image not work     image = open('path/to/image/pug.jpg', 'r+b')     #but image work!?     #image = open('path/to/image/res_tile.png', 'r+b')     files = {'file': image}     r = requests.post(url, files=files)     image.close()     return 'hello world!' 

what have tried:

• first, thought there wrong specific image have tried bunch.
• i have eliminated post , put in 1 module. works.

so, there has wrong in way doing post; works other image. strange.

any appreciated!

edit: ive tried couple of additional ways, both in receiving , sending of post request still no luck. ive found more images work , more don't work. puzzling , irritating. see below more code.

app receives data:

def post():     print "in post"     photo = request.files['file']     in_memory_file = io.bytesio()     photo.save(in_memory_file)     data = np.fromstring(in_memory_file.getvalue(), dtype=np.uint8)     color_image_flag = 1     img = cv2.imdecode(data, color_image_flag)     print img     cv2.imwrite('result.png',img)     return "hello" 

app sends data:

def hello():     url = 'http://ipaddress/post'     image = open('../path/to/image/pug2.png', 'r+b')     files = {'file': ('hej.png', image, 'image/png')}     r = requests.post(url, files=files, stream=true)     image.close()     print r.content     return 'hello world!' 

still no luck.

edit:

now i've tried "multipartencoder" requests_toolbelt , im still facing same issue. on images works. on others not. out there have idea im doing wrong?

app sends request:

def hello():         m = multipartencoder(             fields={'field0': 'value', 'field1': 'value',                     'field2': ('filename', open('../path/to/img', 'rb'), 'image/png')}         )         print m.fields['field0']         r = requests.post('http://192.168.0.3/post', data=m,                   headers={'content-type': m.content_type}) 

app receives request same before, changed access correct field file (with "req = request.files['field2']")

any tips/hits/ideas welcome!

its "solved". or rather, found workaround.

both apps (both receiving , sending image) running locally on machine. pushing receiving app aws , keeping sending app on machine seams have solved issue (at least can see in initial tests). wanted have both locally easier develop seams need have 1 app running non-locally.

if of have idea why works...im ears.