Opening file for append ISSUE

Oak

Hi all, I have an issue that I absolutely cannot get around. When I run my script in the app, it works perfectly fine. Everything is normal. When I call my app through Safari it still runs normally, with the exception that it refuses to append to another file.

So to be clear: the only problem is when accessing the closed app using Pythonista://CoordinatesGet.py?action=run it doesn't write to my file. It DOES write to my file if I call it again, with the app already open, and it DOES write to my file when running the program normally from within the app. Here is my code:

<code>
theFile = open('CoordinatesList.txt','a')
import location
location.start_updates()
myCoords=location.get_location()
location.stop_updates()
longitude=str(myCoords['longitude'])
latitude=str(myCoords['latitude'])

theFile.write('\n')
theFile.write(longitude)
theFile.write('\n')
theFile.write(latitude)

print 'Coordinates:',latitude, longitude
</code>

I really appreciate the help! I'm starting to think it's a bug.

dgelessus

As far as I can tell your code never actually flushes (write to disk) or closes the file. This means that any changes will not be visible until theFile is removed (which happens when you run a new script, because then Pythonista will wipe the Python environment by default). When working with files it's usually best to use the with statement, which will ensure that the file is always properly written and closed:

with open("some_file.txt", "a") as f:
    f.write("some text\n")
    # ... any code that uses the file (f) ...

print("Done!")

Note that the file object (f) can only be used inside the with block. Once that block is exited, f becomes unusable. This means that any code that uses f needs to be in the with block.

(By the way, see this link on how to post code blocks on the forums.)

Phuket2

Not sure if this what you after @Oak. I am very new, but still trying to help as many help me. So take it with a grain of salt


import location, os.path

__FILE_DIR__ = os.path.expanduser('~/Documents/')
__FNAME__ = 'CoordinatesList.txt'

__MY_FILE__ = __FILE_DIR__ + __FNAME__

if not os.path.exists(__MY_FILE__):
	theFile = open(__MY_FILE__, 'w')
	is_new_file = ''
else:
	theFile = open(__MY_FILE__, 'a') 
	is_new_file = '\n'
	
location.start_updates()
myCoords=location.get_location()
location.stop_updates()
longitude=str(myCoords['longitude'])
latitude=str(myCoords['latitude'])

theFile.write(is_new_file)
theFile.write(longitude)
theFile.write('\n')
theFile.write(latitude)

theFile.close()

polymerchm

I thinks the issue might be not closing the file across calls.

try:

import location,time

location.start_updates()
mycoords = location.get_location()
location.stop_updates()

with open('coordinates.txt','a') as fh:
     fh.write(str(mycoords)+'\n'+str(time.ctime())+'\n')

This worked fine for me, but did keep jumping back to pythonista rather than remaining in Safari. Also to better format your code for markdown, use the following approach:

```python

  your code snippet here

```

in your posts to the forum

Oak

Thank you all, you were most certainly right! File was not closing. I have fixed it now by simply using <code> with open </code> for the file.

Thanks again!

polymerchm

Talk about great minds think alike!!!

galewinston

This post is deleted!