Develop Reference

How to print the content of the last saved text file in a folder using Python

I want to print the content of the last saved text file in a folder using Python. I wrote the below code. It is printing out only the path of the file but not the content.
folder_path = r'C:\Users\Siciid\Desktop\restaurant\bill'
file_type = r'\*txt'
files = glob.glob(folder_path + file_type)
max_file = max(files, key=os.path.getctime)
filename=tempfile.mktemp('.txt')
open(filename,'w').write(max_file)
os.startfile(filename,"print")
Is it possible to do this in Python. Any suggestion. I would appreciate your help. Thank you.

You can do that using the following code. Just replace the line where you open and write a file with these two lines:
with open(max_file, "r") as f, open(filename, 'w') as f2:
f2.write(f.read())
The max_file variable contains a file name, not the contents of the file, so writing it to the temp file and printing that will simply print the file name instead of its contents. To put its contents into the temporary file, you need to open the file and then read it. That is what the above two lines of code do.

Upload Excel using web.py

I have tried the following code by slightly modifying the example in documentation
class Upload():
def POST(self):
web.header('enctype','multipart/form-data')
print strftime("%Y-%m-%d %H:%M:%S", gmtime())
x = web.input(file={})
filedir = '/DiginUploads' # change this to the directory you want to store the file in.
if 'file' in x: # to check if the file-object is created
filepath=x.file.filename.replace('\\','/') # replaces the windows-style slashes with linux ones.
filename=filepath.split('/')[-1] # splits the and chooses the last part (the filename with extension)
fout = open(filedir +'/'+ filename,'w') # creates the file where the uploaded file should be stored
fout.write(x.file.file.read()) # writes the uploaded file to the newly created file.
fout.close() # closes the file, upload complete.
But this works only for csv and txt documents. For Excel/pdf etc file gets created but it can't be opened (corrupted). What should I do to handle this scenario?
I saw this but it is about printing the content which does not address my matter.

You need to use wb (binary) mode when opening the file:
fout = open(filedir +'/'+ filename, 'wb')

SFTP with character encoding and line ending options

I am sending a file from one Linux VM to another Linux VM using python which is doing great. Files are sent successfully BUT before I send the file, I want to change the file encoding to "UTF-8" and line ending to "Unix/Linux". How to do that?
Below is the piece of code that is sending the file through sftp:
with pysftp.Connection(host=host, username=userName, password=passWord) as sftpVal:
#print(sftpVal.listdir()) #list directories in sftp home
sftpVal.put(source_file_path,'incoming/'+fileName) #(localPath, destinationPath)

One option would be to read the file contents, change them as you need, save them to a temp file, and send the temp file instead. For example:
with open('file_name.txt') as original_file, open('file_to_send.txt', 'w') as send_file: # Open the original and prepared files
content = original_file.read()
content = content.replace('\r\n', '\n') # Change the line endings
content = content.encode('utf-8') # Encode in UTF-8
send_file.write(content)
# Do your file send here but with the prepared file instead.
os.remove('file_to_send.txt') # Optional removal of temp file.

Python Fabric - erasing my remote file when it should be copying to it

SOLVED
It looks like I needed to close the sys.stdout file (which was open for writing) with a
sys.stdout.close()
and then re-open it, but in read mode, with
sys.stdout = open ('/home/myuser/verify_yslog_conf/remote_hostname/hi', 'r')
and then it uploaded correctly. I used a
time.sleep(60)
to cat the file mid-run for troubleshooting. It was empty until the def had finished, which by default closed the "hi" file. So I realized that I needed to close it to fully write the file. thanks.
Code below is meant to check if syslog is running, and if so, comment out any lines with "#" (but NOT #192.168.x.xx or 192.168.x.xxx) from the pulled remote syslog.conf file. After commenting those lines locally, it is supposed to upload the new file to the remote server in the old location. However, all that happens is that my /etc/syslog.conf file gets erased. The file isn't removed, it is just empty.
I know the issue is from the put statement
fabric.operations.put('/home/myuser/verify_yslog_conf/remote_hostname/hi', '/etc/syslog.conf', use_sudo=True)
but nothing looks wrong with it.
def verify():
#lines below are good; keep them
ip1 = '192.168.x.xx'
ip2 = '92.168.x.xxx'
#check if syslog is running
output = sudo("/sbin/service syslog status")
if 'is running...' in output:
#pull the syslog file from the remote server
fabric.operations.get('/etc/syslog.conf')
#read thru the file
fh = open('/home/myuser/verify_yslog_conf/remote_hostname/syslog.conf', 'r')
f = fh.read()
fh.close()
#if the file needs commenting ...
if re.search(r'(#(?!({0}|{1})))'.format(ip1, ip2), f):
#get the file again -- maybe the problem? was advised to do this
fabric.operations.get('/etc/syslog.conf')
#save the file locally for reading and then for writing (r+ failed)
conf = open ('/home/myuser/verify_yslog_conf/remote_hostname/syslog.conf', 'r')
sys.stdout = open ('/home/myuser/verify_yslog_conf/remote_hostname/hi', 'w')
#for every line in the old /etc/syslog.conf
for line in conf:
#if it has an # but not followed by the permitted IPs
if re.search(r'(#(?!({0}|{1})))'.format(ip1, ip2), line):
#comment out the line then print it (does it twice, dont care)
line = "#" + line
sys.stdout.write(line)
sys.stdout.write(line)
conf.close()
#upload the newly commented file to the remote host
fabric.operations.put('/home/myuser/verify_yslog_conf/remote_hostname/hi', '/etc/syslog.conf', use_sudo=True)
else:
print GOOD
else:
print RSYSLOG

Try to sys.stdout.close() immediately prior to the fabric.operations.put command.
It's likely that before the put operation, the data isn't flushed to the file, so it's sending an empty file, but when the script finishes, it automatically flushes (writes) the data which is why the file appears normal on the local system.

Confusing Error when Reading from a File in Python

I'm having a problem opening the names.txt file. I have checked that I am in the correct directory. Below is my code:
import os
print(os.getcwd())
def alpha_sort():
infile = open('names', 'r')
string = infile.read()
string = string.replace('"','')
name_list = string.split(',')
name_list.sort()
infile.close()
return 0
alpha_sort()
And the error I got:
FileNotFoundError: [Errno 2] No such file or directory: 'names'
Any ideas on what I'm doing wrong?

You mention in your question body that the file is "names.txt", however your code shows you trying to open a file called "names" (without the ".txt" extension). (Extensions are part of filenames.)
Try this instead:
infile = open('names.txt', 'r')

As a side note, make sure that when you open files you use universal mode, as windows and mac/unix have different representations of carriage returns (/r/n vs /n etc.). Universal mode gets python to handle this, so it's generally a good idea to use it whenever you need to read a file. (EDIT - should read: a text file, thanks cameron)
So the code would just look like this
infile = open( 'names.txt', 'rU' ) #capital U indicated to open the file in universal mode

This doesn't solve that issue, but you might consider using with when opening files:
with open('names', 'r') as infile:
string = infile.read()
string = string.replace('"','')
name_list = string.split(',')
name_list.sort()
return 0
This closes the file for you and handles exceptions as well.