Python one liner for extracting url from text

Question

My goal is to write one liner for extracting URLs from text. The problem is that I'm not even able to read data from STDIN. My experiments so far:

└──> grep -i http: flashgot.log | python -c 'import sys; import re; for line in sys.stdin: print line'
  File "<string>", line 1
    import sys; import re; for line in sys.stdin: print line
                             ^
SyntaxError: invalid syntax


└──> grep -i http: flashgot.log | python -c 'import sys; import re; x = [print line for line in sys.stdin]'
  File "<string>", line 1
    import sys; import re; x = [print line for line in sys.stdin]
                                    ^
SyntaxError: invalid syntax

Second plan was to use some of advises from here here here or here

Python is whitespace delimited. There are also no semicolons — OneCricketeer, Jan 09 '16 at 10:41
not sure what your restrictions are, but you can use pickle to load and execute arbitrary code in one line — Michael Xu, Jan 09 '16 at 10:42
my goal is to write quick and dirty script without needing to store it on HDD or something else. — Wakan Tanka, Jan 09 '16 at 10:43
@cricket_007 [yes there are](https://docs.python.org/2/reference/compound_stmts.html). — bereal, Jan 09 '16 at 11:11
@bereal - guess I didn't know python as well as I thought. Thanks — OneCricketeer, Jan 09 '16 at 11:14
@MichaelXu because I know how to do with perl or awk but not in python. — Wakan Tanka, Jan 29 '16 at 11:53

score 1 · Accepted Answer · answered Jan 09 '16 at 11:05

1

I got your snippet working by using sys.stdout.write instead of print:

grep -i http: flashgot.log | python -c 'import sys; import re; [sys.stdout.write("%s\n" % line) for line in sys.stdin]'

I think the problem was not with reading stdin but more with finding the correct syntax to use on one line. On trying your scripts, it looks like for doesn't work as a block in the single-line syntax, and neither does print within a list-generator.

PS: While trying one-line functions, I find that lambda comes in handy sometimes. You might find it useful later in your script

answered Jan 09 '16 at 11:05

Hippo

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Thanks. Is there a way how to explicitly set beginning and end of block? – Wakan Tanka Jan 09 '16 at 12:19
@WakanTanka Not that I know of: I'm also only just experimenting; I haven't managed to find any documentation on the one-liners yet... – Hippo Jan 09 '16 at 12:44

Python one liner for extracting url from text

1 Answers1