I am trying to write a short program that would pass variables for a os.system(). Where the variables are defined as following:
code = 'code.py'
input_file = 'input.xxxx'
output_file = 'output.xxxx'
import os
os.system("python code input_file output_file")
The code works when i specify it as
import os
os.system("python code.py input.xxxx output.xxxx")
But not with variables.
Your help will be greatly appreciated.
Your first attempt at it is passing a string made up of variable names, not their values. Try this:
os.system("python {} {} {}".format(code, input_file, output_file)) # Python 3.x
or
os.system("python {0} {1} {2}".format(code, input_file, output_file)) # Python 2.x
That will insert the variable values into the string for you.
python doesnt recognize the variable names inside quotations. youll have to concatenate the string and the variables like so:
os.system("python " + code + " " + input_file + " " + output_file);
now i forget if python + automatically adds a space or not so you might not need those " " or the space after python
Related
Let's say I have the following file:
credentials:
[default]
key_id = AKIAGHJQTOP
secret_key = alcsjkf
[default2]
key_id = AKIADGHNKVP
secret_key = njprmls
I want to grab the value of [default] key_id. I'm trying to do it with awk command but I'm open to any other way if it's more efficient and easier. Instead of passing a file name to awk, I want to pass the file contents from environmental variable FILE_CONTENTS
I tried the following:
$export VAR=$(echo "$FILE_CONTENTS" | awk '/credentials.default.key_id/ {print $2}')
But it didn't work. Any help is appreciated.
You can use awk like this:
cat srch.awk
BEGIN { FS = " *= *" }
{ sub(/^[[:blank:]]+/, "") }
/:[[:blank:]]*$/ {
sub(/:[[:blank:]]*$/, "")
k = $1
}
/^[[:blank:]]*\[/ {
s = k "." $1
}
NF == 2 {
map[s "." $1] = $2
}
key in map {
print map[key]
exit
}
# then use it as
echo "$FILE_CONTENTS" |
awk -v key='credentials.[default].key_id' -f srch.awk
AKIAGHJQTOP
# or else
echo "$FILE_CONTENTS" |
awk -v key='credentials.[default].secret_key' -f srch.awk
alcsjkf
With your shown samples, please try following awk code. Written and tested in GNU awk.
awk -v RS='(^|\\n)credentials:\\n[[:space:]]+\\[default\\]\\n[[:space:]]+key_id = \\S+' '
RT && num=split(RT,arr," key_id = "){
print arr[num]
}
' Input_file
Here is the Online demo for used regex(its bit changed from regex used in awk code as escaping is done in program not in site).
Assumptions:
no spaces between labels and :
no spaces between [ the stanza name and ]
all lines with attribute/value pairs have exactly 3 space-delimited fields as shown (ie, attr = value; value has no embedded spaces)
the contents of OP's variable (FILE_CONTENTS) is an exact copy (data and format) of the sample file provided by OP
NOTE: if the input file format can differ from these assumptions then additional code must be added to address said differences; as mentioned in comments ... writing your own parser is doable but you need to insure you address all possible format variations
One awk idea:
awk -v label='credentials' -v stanza='default' -v attr='key_id' '
/:/ { f1=0; if ($0 ~ label ":") f1=1 }
f1 && /[][]/ { f2=0; if ($0 ~ "[" stanza "]") f2=1 }
f1 && f2 && /=/ { if ($1 == attr) { print $3; f1=f2=0 } }
'
This generates:
AKIAGHJQTOP
$ awk 'f{print $3; exit} /\[default]/{f=1}' <<<"$FILE_CONTENTS"
AKIAGHJQTOP
If that's not all you need then edit your question to provide more truly realistic sample input/output including cases where the above doesn't work.
open to any other way if it's more efficient and easier
I suggest taking look at python's configparser, which is part of standard library. Let FILE_CONTENTS environment variable be holding
credentials:
[default]
key_id = AKIAGHJQTOP
secret_key = alcsjkf
[default2]
key_id = AKIADGHNKVP
secret_key = njprmls
then create file getkeyid.py with content as follows
import configparser
import os
config = configparser.ConfigParser()
config.read_string(os.environ["FILE_CONTENTS"].replace("credentials","#credentials",1))
print(config["default"]["key_id"])
and do
python3 getkeyid.py
to get output
AKIAGHJQTOP
Explanation: I retrieve string from environmental variable and replace credentials with #credentials at most 1 time in order to comment that line (otherwise parser will fail), then parse it and retrieve value corresponding to desired key.
I've been playing around with this for an hour trying to work out how to embed the removal of quotes from a specific field using AWK.
Basically, the file encapsulates text in quotes, but I want to use the second field to name the file and split them based on the first field.
ID,Name,Value1,Value2,Value3
1,"AAA","DEF",1,2
1,"AAA","GGG",7,9
2,"BBB","DEF",1,2
2,"BBB","DEF",9,0
3,"CCC","AAA",1,1
What I want to get out are three files, all with the header row named:
AAA [1].csv
BBB [2].csv
CCC [3].csv
I have got it all working, except for the fact that I can't for the life of me work out how to remove the quotes around the filename!!
So, this command does everything (except the file is named with quotes around $2, but I need to do some kind of transformation on $2 before it goes into evname. In the actual file, I want to keep the encapsulating quotes.
awk -F, 'NR==1{h=$0;next}!($1 in files){evname=$2" ["$1"].csv";files[$1]=1;print h>evname}{print > evname}' DataExtract.csv
I've tried to push a gsub into this, but I'm struggling to work out exactly how this should look.
This is I think as close as I have got, but it is just calling everything "2" for $2, I'm not sure if this means I need to do an escape of $2 somehow in the gsub, but trying that doesn't seem to be working, so I'm at a loss as to what I'm doing wrong.
awk -F, 'NR==1{h=$0;next}!($1 in files){evname=gsub(""\","", $2)" - Event ID ["$1"].csv";files[$1]=1;print h>evname}{print > evname}' DataExtract.csv
Any help greatly appreciated.
Thanks in advance!!
Gannon
If I understand what you are attempting correctly, then
awk -F, 'NR==1{h=$0;next}!($1 in files){gsub(/"/, "", $2); evname=$2" ["$1"].csv";files[$1]=1;print h>evname}{print > evname}' DataExtract.csv
should work. That is
NR == 1 {
h = $0;
next
}
!($1 in files) {
stub = $2 # <-- this is the new bit: make a working copy
# of $2 (so that $2 is unchanged and the line
# is not rebuilt with changes for printing),
gsub(/"/, "", stub) # remove the quotes from it, and
evname = stub " [" $1 "].csv" # use it to assemble the filename.
files[$1] = 1;
print h > evname
}
{
print > evname
}
You can, of course, use
evname = stub " - Event ID [" $1 "].csv"
or any other format after the substitution (this one seems to be what you tried to get in your second code snippet).
The gsub function returns the number of substitutions made, not the result of the substitutions; that is why evname=gsub(""\","", $2)" - Event ID ["$1"].csv" does not work.
Things are always clearer with a little white space:
awk -F, '
NR==1 { hdr=$0; next }
!seen[$1]++ {
evname = $2
gsub(/"/,"",evname)
outfile = evname " [" $1 "].csv"
print hdr > outfile
}
{ print > outfile }
' DataExtract.csv
Aside: It's pretty unusual for someone to WANT to create files with spaces in their names given the complexity that introduces in any later scripts you write to process them. You sure you want to do that?
P.S. here's the gawk version as suggested by #JID below
awk -F, '
NR==1 { hdr=$0; next }
!seen[$1]++ {
outfile = gensub(/"/,"","g",$2) " [" $1 "].csv"
print hdr > outfile
}
{ print > outfile }
' DataExtract.csv
Apply the gsub before you make the assignment:
awk -F, 'NR==1{h=$0;next}
!($1 in files){
gsub("\"","",$2); # Add this line
evname=$2" ["$1"].csv";files[$1]=1;print...
Please pardon me in advance for posting such a big part of my problem, but I just can't put my finger on the part that fails...
I got input-files like this (abas-FO if you care to know):
.fo U|xiininputfile = whatever
.type text U|xigibsgarnich
.assign U|xigibsgarnich
..
..Comment
.copy U|xigibswohl = Spaß
.ein "ow1/UWEDEFTEST.FOP"
.in "ow1/UWEINPUT2"
.continue BOTTOM
.read "SOemthing" U|xttmp
!BOTTOM
..
..
Now I want to recursivly follow each .in[put]/.ein[gabe]-statement, parse the mentioned file and if I don't know it yet, add it to an array. My code looks like this:
#!/bin/awk -f
function getFopMap(inputregex, infile, mandantdir, infiles){
while(getline f < infile){
#printf "*"
#don't match if there is a '
if(f ~ inputregex "[^']"){
#remove .input-part
sub(inputregex, "", f)
#trim right
sub(/[[:blank:]]+$/, "", f)
#remove leading and trailing "
gsub(/(^\"|\"$)/,"" ,f)
if(!(f in infiles)){
infiles[f] = "found"
}
}
}
close(infile)
for (i in infiles){
if(infiles[i] == "found"){
infiles[i] = "parsed"
cmd = "test -f \"" i "\""
if(system(cmd) == 0){
close(cmd)
getFopMap(inputregex, f, mandantdir, infiles)
}
}
}
}
BEGIN{
#Matches something like [.input myfile] or [.ein "ow1/myfile"]
inputregex = "^\\.(in|ein)[^[:blank:]]*[[:blank:]]+"
#Get absolute path of infile
cmd = "python -c 'import os;print os.path.abspath(\"" ARGV[1] "\")'"
cmd | getline rootfile
close(cmd)
infiles[rootfile] = "parsed"
getFopMap(inputregex, rootfile, mandantdir, infiles)
#output result
for(infile in infiles) print infile
exit
}
I call the script (in the same directory the paths are relative to) like this:
./script ow1/UWEDEFTEST.FOP
I get no output. It just hangs up. If I remove the comment before the printf "*" command, I'm seeing stars, without end.
I appreciate every help and hints how to do it better.
My awk:
gawk Version 3.1.7
idk it it's your only problem but you're calling getline incorrectly and consequently will go into an infinite loop in some scenarios. Make sure you fully understand all of the caveats at http://awk.info/?tip/getline and you might want to use the recursion example there as the starting point for your code.
The most important item initially for your code is that when getline fails it can return a negative value so then while(getline f < infile) will create an infinite loop since the failing getline will always be returning non-zero and will so continue to be called and continue to fail. You need to use while ( (getline f < infile) > 0) instead.
#!/bin/awk -f
{
if (length($0) < 80)
{
prefix = "";
for (i = 1;i<(80-length($0))/2;i++)
prefix = prefix " ";
print prefix $0;
}
else
{
print;
}
}
Could any one please tell me what exactly the prefix variable is doing in the above code.
This is to make the incoming text as Centre Aligned text.
Read the text
Declare a empty string in the variable name prefix
Calculate the position where to paste your text is determined by the for loop by prefixing spaces for the same. In this case, we print spaces until we are at the position at ((80 - length of your string ) /2)
Print your string
Note: $0 in AWK is your complete string like "I want to test this" where as $1 will be "I" and $2 will be "want", where as in shell it prints your current shell you are working with
It's adding front padding to center the string on the line if it's shorter than the line length but you can do the same thing with just:
awk '{ printf "%*s\n",(80+length($0))/2, $0 }' file
It increments prefix with blank space to create a line with space in front according to the formula.
echo "test" | awk -f script
test
it builds an empty string place holder (for left padding), which has length= (80-length of the line)/2
In PowerShell, you can expand variables within strings as shown below:
$myvar = "hello"
$myvar1 = "$myvar`world" #without the `, powershell would look for a variable called $myvarworld
Write-Host $myvar1 #prints helloworld
The problem I am having is with escaped characters like nr etc, as shown below:
$myvar3 = "$myvar`albert"
Write-Host $myvar3 #prints hellolbert as `a is an alert
also the following doesnt work:
$myvar2 = "$myvar`frank" #doesnt work
Write-Host $myvar2 #prints hellorank.
Question:
How do I combine the strings without worrying about escaped characters when I am using the automatic variable expansion featurie?
Or do I have to do it only this way:
$myvar = "hello"
$myvar1 = "$myvar"+"world" #using +
Write-Host $myvar1
$myvar2 = "$myvar"+"frank" #using +
This way is not yet mentioned:
"$($myvar)frank"
And this:
"${myvar}frank"
This seems kind of kludgy, but as another option, you can add a space and a backspace:
$myvar = "hello"
$myvar1 = "$myvar `bworld"
$myvar1
Yet another option is to wrap your variable expression in a $():
$myvar3 = "$($myvar)albert"
Write-Host $myvar3
One other option is through the format operator:
"{0}world" -f $myvar
Another option is a double-quoted here-string:
$myvar = "Hello"
$myvar2 = #"
$myvar$("frank")
"#