How do I convert a Python UUID into a string?

Question

I need to be able to assign a UUID to a user and document this in a .txt file. This is all I have:

import uuid

a = input("What's your name?")
print(uuid.uuid1())
f.open(#file.txt)

I tried:

f.write(uuid.uuid1())

but nothing comes up, may be a logical error but I don't know.

Solution 1

you can try this !

 a = uuid.uuid1()
 str(a)
 --> '448096f0-12b4-11e6-88f1-180373e5e84a'

Solution 2

You can also do this. Removes the dashes as a bonus. link to docs.

import uuid
my_id = uuid.uuid4().hex

ffba27447d8e4285b7bdb4a6ec76db5c

UPDATE: trimmed UUIDs (without the dashes) are functionally identical to full UUIDS (discussion). The dashes in full UUIDs are always in the same position (article).

Solution 3

I came up with a different solution that worked for me as expected with Python 3.7.

import uuid

uid_str = uuid.uuid4().urn
your_id = uid_str[9:]

urn is the UUID as a URN as specified in RFC 4122.

Solution 4

It's probably because you're not actually closing your file. This can cause problems. You want to use the context manager/with block when dealing with files, unless you really have a reason not to.

with open('file.txt', 'w') as f:
    # Do either this
    f.write(str(uuid.uuid1()))
    # **OR** this.
    # You can leave out the `end=''` if you want.
    # That was just included so that the two of these
    # commands do the same thing.
    print(uuid.uuid1(), end='', file=f)

This will automatically close your file when you're done, which will ensure that it's written to disk.

Solution 5

[update] i added str function to write it as string and close the file to make sure it does it immediately,before i had to terminate the program so the content would be write

 import uuid
 def main():
     a=input("What's your name?")
     print(uuid.uuid1())
 main()
 f=open("file.txt","w")
 f.write(str(uuid.uuid1()))
 f.close()

I guess this works for me

View more solutions

Comments

[Ignacio Vazquez-Abrams]

Have you had a chance to look at the uuid documentation?

[Alphin Philip]

@IgnacioVazquez-Abrams I'm quite new to python and I'm sorry, but I'm not too sure what you mean.

[khelwood]

You can change a uuid to a string by putting str(...) around it, if that is actually what you're asking.

[Eliethesaiyan]

because the input is gained through main..is considered as variable...try to use quotation around when you re input... and also f=open("file.txt") not with dot

[Greg]

How about uuid.uuid4().hex? It returns a 32-character string.

[Alphin Philip]

I tried this and it keeps coming back as: TypeError: write() argument must be str, not UUID

[Alphin Philip]

I tried this and it keeps coming back as: TypeError: write() argument must be str, not UUID#

[Wayne Werner]

@AlphinPhilip updated my answer - you can do either one. The latter assumes that you're running python3.x+ or have run from __future__ import print_function

[Eliethesaiyan]

@AlphinPhilip i hope you fixed it by then

[Felipe]

who downvoted this? The question is "How do I change a UUID to a string?" and this answers the question just fine. It's not going to return anything because it's showing how to turn a UUID into a string representation. Voting +1

[djvg]

Not sure if this matters to you, but it seems to me that the uuid1 you are printing is not the same as the one you are writing to file, because uuid.uuid1() != uuid.uuid1()

[Eliethesaiyan]

@Dennis, i was giving alternatives...either he can print it or generate it in astring variable and write it...or generate it and write it directly

[Adam Mlodzinski]

Will str(UUID) always return a string consisting of alphanumerics-plus-dashes? I couldn't find docs on UUID.__str__(). Or, would I need to use something like UUID.hex() or UUID.urn(), to ensure there are no non-printable characters in the resultant string?

[sumit]

@AdamMlodzinski Yes, from official python documentation docs.python.org/3/library/uuid.html#module-uuid and also check the source code for str method github.com/python/cpython/blob/master/Lib/uuid.py#L279

[Rohan Devaki]

thankyou sir, do you have link to the docs?

[Rohan Devaki]

and will this still be unique? if we remove the dashes?

[andyw]

i've edited my answer to make link to docs more obvious.

[andyw]

updated my answer with respect to the impact of removing dashes.