Mixing
How to create a many-to-many relationship variable and increase code usability?
I'm trying to create a common utility for file transfer, from source to destination. The arguments are separated into dir and filename, which is the result of os.path.dirname(some_file) and os.path.basename(some_file), respectively. The destination filename is the same as the source filename by default if not specified.
I have created a script that at least is working perfectly well with the specific requirements in my first project. But as you can notice, the get_src_des method is very repetitive that I want to improve the code re-usability out from the nasty if...elif... statement. Anyone has better idea to rewrite this method?
class FileTransfer:
def __init__(self, ftp_dir, local_dir, ftp_filename=None, local_filename=None):
self.ftp_dir = ftp_dir
self.ftp_filename = ftp_filename
self.local_dir = local_dir
self.local_filename = local_filename
self.ftp_dict = self.get_group(ftp_dir, ftp_filename)
self.local_dict = self.get_group(local_dir, local_filename)
@staticmethod
def get_group(dir, filename):
group = {
"dir": dir,
"filename": filename,
}
return group
def get_src_des(self, src):
if src == "ftp":
dict_src = self.ftp_dict
dict_des = self.local_dict
elif src == "local":
dict_src = self.local_dict
dict_des = self.ftp_dict
else:
dict_src = None
dict_des = None
return dict_src, dict_des
# other methods, such as download_from_src_to_des, upload_from_src_to_des, ...
python
edited Jan 1 at 22:01
martineau
69k1091186
asked Jan 1 at 21:30
D EmmaD Emma
62
add a comment |
I'm trying to create a common utility for file transfer, from source to destination. The arguments are separated into dir and filename, which is the result of os.path.dirname(some_file) and os.path.basename(some_file), respectively. The destination filename is the same as the source filename by default if not specified.
I have created a script that at least is working perfectly well with the specific requirements in my first project. But as you can notice, the get_src_des method is very repetitive that I want to improve the code re-usability out from the nasty if...elif... statement. Anyone has better idea to rewrite this method?
class FileTransfer:
def __init__(self, ftp_dir, local_dir, ftp_filename=None, local_filename=None):
self.ftp_dir = ftp_dir
self.ftp_filename = ftp_filename
self.local_dir = local_dir
self.local_filename = local_filename
self.ftp_dict = self.get_group(ftp_dir, ftp_filename)
self.local_dict = self.get_group(local_dir, local_filename)
@staticmethod
def get_group(dir, filename):
group = {
"dir": dir,
"filename": filename,
}
return group
def get_src_des(self, src):
if src == "ftp":
dict_src = self.ftp_dict
dict_des = self.local_dict
elif src == "local":
dict_src = self.local_dict
dict_des = self.ftp_dict
else:
dict_src = None
dict_des = None
return dict_src, dict_des
# other methods, such as download_from_src_to_des, upload_from_src_to_des, ...
python
edited Jan 1 at 22:01
martineau
69k1091186
asked Jan 1 at 21:30
D EmmaD Emma
62
add a comment |
I'm trying to create a common utility for file transfer, from source to destination. The arguments are separated into dir and filename, which is the result of os.path.dirname(some_file) and os.path.basename(some_file), respectively. The destination filename is the same as the source filename by default if not specified.
I have created a script that at least is working perfectly well with the specific requirements in my first project. But as you can notice, the get_src_des method is very repetitive that I want to improve the code re-usability out from the nasty if...elif... statement. Anyone has better idea to rewrite this method?
class FileTransfer:
def __init__(self, ftp_dir, local_dir, ftp_filename=None, local_filename=None):
self.ftp_dir = ftp_dir
self.ftp_filename = ftp_filename
self.local_dir = local_dir
self.local_filename = local_filename
self.ftp_dict = self.get_group(ftp_dir, ftp_filename)
self.local_dict = self.get_group(local_dir, local_filename)
@staticmethod
def get_group(dir, filename):
group = {
"dir": dir,
"filename": filename,
}
return group
def get_src_des(self, src):
if src == "ftp":
dict_src = self.ftp_dict
dict_des = self.local_dict
elif src == "local":
dict_src = self.local_dict
dict_des = self.ftp_dict
else:
dict_src = None
dict_des = None
return dict_src, dict_des
# other methods, such as download_from_src_to_des, upload_from_src_to_des, ...
python
edited Jan 1 at 22:01
martineau
69k1091186
asked Jan 1 at 21:30
D EmmaD Emma
62
I'm trying to create a common utility for file transfer, from source to destination. The arguments are separated into dir and filename, which is the result of os.path.dirname(some_file) and os.path.basename(some_file), respectively. The destination filename is the same as the source filename by default if not specified.
I have created a script that at least is working perfectly well with the specific requirements in my first project. But as you can notice, the get_src_des method is very repetitive that I want to improve the code re-usability out from the nasty if...elif... statement. Anyone has better idea to rewrite this method?
class FileTransfer:
def __init__(self, ftp_dir, local_dir, ftp_filename=None, local_filename=None):
self.ftp_dir = ftp_dir
self.ftp_filename = ftp_filename
self.local_dir = local_dir
self.local_filename = local_filename
self.ftp_dict = self.get_group(ftp_dir, ftp_filename)
self.local_dict = self.get_group(local_dir, local_filename)
@staticmethod
def get_group(dir, filename):
group = {
"dir": dir,
"filename": filename,
}
return group
def get_src_des(self, src):
if src == "ftp":
dict_src = self.ftp_dict
dict_des = self.local_dict
elif src == "local":
dict_src = self.local_dict
dict_des = self.ftp_dict
else:
dict_src = None
dict_des = None
return dict_src, dict_des
# other methods, such as download_from_src_to_des, upload_from_src_to_des, ...
python
python
edited Jan 1 at 22:01
martineau
69k1091186
asked Jan 1 at 21:30
D EmmaD Emma
62
edited Jan 1 at 22:01
martineau
69k1091186
asked Jan 1 at 21:30
D EmmaD Emma
62
edited Jan 1 at 22:01
martineau
69k1091186
edited Jan 1 at 22:01
martineau
69k1091186
edited Jan 1 at 22:01
martineau
69k1091186
69k1091186
asked Jan 1 at 21:30
D EmmaD Emma
62
asked Jan 1 at 21:30
D EmmaD Emma
62
asked Jan 1 at 21:30
D EmmaD Emma
62
62
add a comment |
add a comment |
2 Answers
2
active
oldest
votes
Yes. This is classic use case for a dictionary.
You can rewrite your code as follows:
class FileTransfer:
def __init__(self, ftp_dir, local_dir, ftp_filename=None, local_filename=None):
self.ftp_dir = ftp_dir
self.ftp_filename = ftp_filename
self.local_dir = local_dir
self.local_filename = local_filename
self.ftp_dict = self.get_group(ftp_dir, ftp_filename)
self.local_dict = self.get_group(local_dir, local_filename)
self.param_dict = {
'ftp':(self.ftp_dict,self.local_dict),
'local' : (self.local_dict,self.ftp_dict)
}
@staticmethod
def get_group(dir, filename):
group = {
"dir": dir,
"filename": filename,
}
return group
def get_src_des(self, src):
if src in param_dict:
return param_dict[src]
else:
return (None,None)
Next time, instead of adding another elif statement, you just add another entry in your param_dict
edited Jan 1 at 22:46
Josué Cortina
1,5861512
answered Jan 1 at 21:37
Yakov DanYakov Dan
1,401717
add a comment |
I agree that that this could be done with a dictionary, as @Yakov Dan's answer suggests, but I would code it as shown below, which doesn't require any other changes to the class and is more dynamic.
The get_group() method could be written more concisely, as indicated.
class FileTransfer:
...
@staticmethod
def get_group(dir, filename):
return dict(dir=dir, filename=filename)
def get_src_des(self, src):
return {
'ftp': (self.ftp_dict, self.local_dict),
'local': (self.local_dict, self.ftp_dict)
}.get(src, (None, None))
answered Jan 1 at 22:24
martineaumartineau
69k1091186
This version ofget_src_descreates the dict each time. Creating it once in__init__is more efficient.
– cco
Jan 1 at 23:33
@cco: True, but creating it on-the-fly means that it uses the current values of the instance's attributes, not what they were when it was created. It also doesn't require modifying any other parts of the class—so unless doing it dynamically as show is causing a significant slow-down—so it sounds to me like your suggestion is a premature optimization.
– martineau
Jan 1 at 23:51
add a comment |
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2 Answers
2
active
oldest
votes
2 Answers
2
active
oldest
votes
active
oldest
votes
active
oldest
votes
Yes. This is classic use case for a dictionary.
You can rewrite your code as follows:
class FileTransfer:
def __init__(self, ftp_dir, local_dir, ftp_filename=None, local_filename=None):
self.ftp_dir = ftp_dir
self.ftp_filename = ftp_filename
self.local_dir = local_dir
self.local_filename = local_filename
self.ftp_dict = self.get_group(ftp_dir, ftp_filename)
self.local_dict = self.get_group(local_dir, local_filename)
self.param_dict = {
'ftp':(self.ftp_dict,self.local_dict),
'local' : (self.local_dict,self.ftp_dict)
}
@staticmethod
def get_group(dir, filename):
group = {
"dir": dir,
"filename": filename,
}
return group
def get_src_des(self, src):
if src in param_dict:
return param_dict[src]
else:
return (None,None)
Next time, instead of adding another elif statement, you just add another entry in your param_dict
edited Jan 1 at 22:46
Josué Cortina
1,5861512
answered Jan 1 at 21:37
Yakov DanYakov Dan
1,401717
add a comment |
Yes. This is classic use case for a dictionary.
You can rewrite your code as follows:
class FileTransfer:
def __init__(self, ftp_dir, local_dir, ftp_filename=None, local_filename=None):
self.ftp_dir = ftp_dir
self.ftp_filename = ftp_filename
self.local_dir = local_dir
self.local_filename = local_filename
self.ftp_dict = self.get_group(ftp_dir, ftp_filename)
self.local_dict = self.get_group(local_dir, local_filename)
self.param_dict = {
'ftp':(self.ftp_dict,self.local_dict),
'local' : (self.local_dict,self.ftp_dict)
}
@staticmethod
def get_group(dir, filename):
group = {
"dir": dir,
"filename": filename,
}
return group
def get_src_des(self, src):
if src in param_dict:
return param_dict[src]
else:
return (None,None)
Next time, instead of adding another elif statement, you just add another entry in your param_dict
edited Jan 1 at 22:46
Josué Cortina
1,5861512
answered Jan 1 at 21:37
Yakov DanYakov Dan
1,401717
add a comment |
Yes. This is classic use case for a dictionary.
You can rewrite your code as follows:
class FileTransfer:
def __init__(self, ftp_dir, local_dir, ftp_filename=None, local_filename=None):
self.ftp_dir = ftp_dir
self.ftp_filename = ftp_filename
self.local_dir = local_dir
self.local_filename = local_filename
self.ftp_dict = self.get_group(ftp_dir, ftp_filename)
self.local_dict = self.get_group(local_dir, local_filename)
self.param_dict = {
'ftp':(self.ftp_dict,self.local_dict),
'local' : (self.local_dict,self.ftp_dict)
}
@staticmethod
def get_group(dir, filename):
group = {
"dir": dir,
"filename": filename,
}
return group
def get_src_des(self, src):
if src in param_dict:
return param_dict[src]
else:
return (None,None)
Next time, instead of adding another elif statement, you just add another entry in your param_dict
edited Jan 1 at 22:46
Josué Cortina
1,5861512
answered Jan 1 at 21:37
Yakov DanYakov Dan
1,401717
Yes. This is classic use case for a dictionary.
You can rewrite your code as follows:
class FileTransfer:
def __init__(self, ftp_dir, local_dir, ftp_filename=None, local_filename=None):
self.ftp_dir = ftp_dir
self.ftp_filename = ftp_filename
self.local_dir = local_dir
self.local_filename = local_filename
self.ftp_dict = self.get_group(ftp_dir, ftp_filename)
self.local_dict = self.get_group(local_dir, local_filename)
self.param_dict = {
'ftp':(self.ftp_dict,self.local_dict),
'local' : (self.local_dict,self.ftp_dict)
}
@staticmethod
def get_group(dir, filename):
group = {
"dir": dir,
"filename": filename,
}
return group
def get_src_des(self, src):
if src in param_dict:
return param_dict[src]
else:
return (None,None)
Next time, instead of adding another elif statement, you just add another entry in your param_dict
edited Jan 1 at 22:46
Josué Cortina
1,5861512
answered Jan 1 at 21:37
Yakov DanYakov Dan
1,401717
edited Jan 1 at 22:46
Josué Cortina
1,5861512
edited Jan 1 at 22:46
Josué Cortina
1,5861512
edited Jan 1 at 22:46
Josué Cortina
1,5861512
1,5861512
answered Jan 1 at 21:37
Yakov DanYakov Dan
1,401717
answered Jan 1 at 21:37
Yakov DanYakov Dan
1,401717
answered Jan 1 at 21:37
Yakov DanYakov Dan
1,401717
1,401717
add a comment |
add a comment |
I agree that that this could be done with a dictionary, as @Yakov Dan's answer suggests, but I would code it as shown below, which doesn't require any other changes to the class and is more dynamic.
The get_group() method could be written more concisely, as indicated.
class FileTransfer:
...
@staticmethod
def get_group(dir, filename):
return dict(dir=dir, filename=filename)
def get_src_des(self, src):
return {
'ftp': (self.ftp_dict, self.local_dict),
'local': (self.local_dict, self.ftp_dict)
}.get(src, (None, None))
answered Jan 1 at 22:24
martineaumartineau
69k1091186
This version ofget_src_descreates the dict each time. Creating it once in__init__is more efficient.
– cco
Jan 1 at 23:33
@cco: True, but creating it on-the-fly means that it uses the current values of the instance's attributes, not what they were when it was created. It also doesn't require modifying any other parts of the class—so unless doing it dynamically as show is causing a significant slow-down—so it sounds to me like your suggestion is a premature optimization.
– martineau
Jan 1 at 23:51
add a comment |
I agree that that this could be done with a dictionary, as @Yakov Dan's answer suggests, but I would code it as shown below, which doesn't require any other changes to the class and is more dynamic.
The get_group() method could be written more concisely, as indicated.
class FileTransfer:
...
@staticmethod
def get_group(dir, filename):
return dict(dir=dir, filename=filename)
def get_src_des(self, src):
return {
'ftp': (self.ftp_dict, self.local_dict),
'local': (self.local_dict, self.ftp_dict)
}.get(src, (None, None))
answered Jan 1 at 22:24
martineaumartineau
69k1091186
This version ofget_src_descreates the dict each time. Creating it once in__init__is more efficient.
– cco
Jan 1 at 23:33
@cco: True, but creating it on-the-fly means that it uses the current values of the instance's attributes, not what they were when it was created. It also doesn't require modifying any other parts of the class—so unless doing it dynamically as show is causing a significant slow-down—so it sounds to me like your suggestion is a premature optimization.
– martineau
Jan 1 at 23:51
add a comment |
I agree that that this could be done with a dictionary, as @Yakov Dan's answer suggests, but I would code it as shown below, which doesn't require any other changes to the class and is more dynamic.
The get_group() method could be written more concisely, as indicated.
class FileTransfer:
...
@staticmethod
def get_group(dir, filename):
return dict(dir=dir, filename=filename)
def get_src_des(self, src):
return {
'ftp': (self.ftp_dict, self.local_dict),
'local': (self.local_dict, self.ftp_dict)
}.get(src, (None, None))
answered Jan 1 at 22:24
martineaumartineau
69k1091186
I agree that that this could be done with a dictionary, as @Yakov Dan's answer suggests, but I would code it as shown below, which doesn't require any other changes to the class and is more dynamic.
The get_group() method could be written more concisely, as indicated.
class FileTransfer:
...
@staticmethod
def get_group(dir, filename):
return dict(dir=dir, filename=filename)
def get_src_des(self, src):
return {
'ftp': (self.ftp_dict, self.local_dict),
'local': (self.local_dict, self.ftp_dict)
}.get(src, (None, None))
answered Jan 1 at 22:24
martineaumartineau
69k1091186
edited Jan 1 at 22:32
answered Jan 1 at 22:24
martineaumartineau
69k1091186
answered Jan 1 at 22:24
martineaumartineau
69k1091186
answered Jan 1 at 22:24
martineaumartineau
69k1091186
69k1091186
This version ofget_src_descreates the dict each time. Creating it once in__init__is more efficient.
– cco
Jan 1 at 23:33
@cco: True, but creating it on-the-fly means that it uses the current values of the instance's attributes, not what they were when it was created. It also doesn't require modifying any other parts of the class—so unless doing it dynamically as show is causing a significant slow-down—so it sounds to me like your suggestion is a premature optimization.
– martineau
Jan 1 at 23:51
add a comment |
This version ofget_src_descreates the dict each time. Creating it once in__init__is more efficient.
– cco
Jan 1 at 23:33
@cco: True, but creating it on-the-fly means that it uses the current values of the instance's attributes, not what they were when it was created. It also doesn't require modifying any other parts of the class—so unless doing it dynamically as show is causing a significant slow-down—so it sounds to me like your suggestion is a premature optimization.
– martineau
Jan 1 at 23:51
This version of
get_src_des creates the dict each time. Creating it once in __init__ is more efficient.– cco
Jan 1 at 23:33
This version of
get_src_des creates the dict each time. Creating it once in __init__ is more efficient.– cco
Jan 1 at 23:33
@cco: True, but creating it on-the-fly means that it uses the current values of the instance's attributes, not what they were when it was created. It also doesn't require modifying any other parts of the class—so unless doing it dynamically as show is causing a significant slow-down—so it sounds to me like your suggestion is a premature optimization.
– martineau
Jan 1 at 23:51
@cco: True, but creating it on-the-fly means that it uses the current values of the instance's attributes, not what they were when it was created. It also doesn't require modifying any other parts of the class—so unless doing it dynamically as show is causing a significant slow-down—so it sounds to me like your suggestion is a premature optimization.
– martineau
Jan 1 at 23:51
add a comment |
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