I am new to scripting, I am trying to write a simple script for sensu check to create an alert for Disk Space.
The below command produces an output:
#!/usr/bin/ruby
a = `df -h / | grep -v "Filesystem" | awk '{print $5}'`
puts a
Assume that the output is 35%
now I want to strip down the %, when I try using a.chop! still it is not removing the %
Could some one please help me stripping off the % from the output.
The value returned from your command has a newline at its end:
a
# => "35%\n"
To remove the % using chop you need to strip! it first:
a.strip!
a.chop!
# => "35"
Since you're going to use this in a numeric comparison just convert it to an integer in one step:
a = `df -h / | grep -v "Filesystem" | awk '{print $5}'`
puts a.to_i
# => 66
Related
I'm trying to create a bash function that automatically updates a cli tool. So far I've managed to get this:
update_cli_tool () {
# the following will automatically be redirected to .../releases/tag/vX.X.X
# there I get the location from the header, and remove it to get the full url
latest_release_url=$(curl -i https://github.com/.../releases/latest | grep location: | awk -F 'location: ' '{print $2}')
# to get the version, I get the 8th element from the url .../releases/tag/vX.X.X
latest_release_version=$(echo "$latest_release_url" | awk -F '/' '{print 8}')
# this is where it breaks
# the first part just replaces the "tag" with "download" in the url
full_url="${latest_release_url/tag/download}/.../${latest_release_version}.zip"
echo "$full_url" # or curl $full_url, also fails
}
Expected output: https://github.com/.../download/vX.X.X/vX.X.X.zip
Actual output: -.zip-.../.../releases/download/vX.X.X
When I just echo "latest_release_url: $latest_release_url" (same for version), it prints it correctly, but not when I use the above mentioned flow. When I hardcode the ..._url and ..._version, the full_url works fine. So my guess is I have to somehow capture the output and convert it to a string? Or perhaps concatenate it another way?
Note: I've also used ..._url=`curl -i ...` (with backticks instead of $(...)), but this gave me the same results.
The curl output will use \r\n line endings. The stray carriage return in the url variable is tripping you up. Observe it with printf '%q\n' "$latest_release_url"
Try this:
latest_release_url=$(
curl --silent -i https://github.com/.../releases/latest \
| awk -v RS='\r\n' '$1 == "location:" {print $2}'
)
Then the rest of the script should look right.
I have to get my db credentials from this configuration file:
# Database settings
Aisse.LocalHost=localhost
Aisse.LocalDataBase=mydb
Aisse.LocalPort=5432
Aisse.LocalUser=myuser
Aisse.LocalPasswd=mypwd
# My other app settings
Aisse.NumDir=../../data/Num
Aisse.NumMobil=3000
# Log settings
#Aisse.Trace_AppliTpv=blabla1.tra
#Aisse.Trace_AppliCmp=blabla2.tra
#Aisse.Trace_AppliClt=blabla3.tra
#Aisse.Trace_LocalDataBase=blabla4.tra
In particular, I want to get the value mydb from line
Aisse.LocalDataBase=mydb
So far, I have developed this
mydbname=$(echo "$my_conf_file.conf" | grep "LocalDataBase=" | sed "s/LocalDataBase=//g" )
that returns
mydb #Aisse.Trace_blabla4.tra
that would be ok if it did not return also the comment string.
Then I have also tryed
mydbname=$(echo "$my_conf_file.conf" | grep "Aisse.LocalDataBase=" | sed "s/LocalDataBase=//g" )
that retruns void string.
How can I get only the value that is preceded by the string "Aisse.LocalDataBase=" ?
Using sed
$ mydbname=$(sed -n 's/Aisse\.LocalDataBase=//p' input_file)
$ echo $mydbname
mydb
I'm afraid you're being incomplete:
You mention you want the line, containing "LocalDataBase", but you don't want the line in comment, let's start with that:
A line which contains "LocalDataBase":
grep "LocalDataBase" conf.conf.txt
A line which contains "LocalDataBase" but who does not start with a hash:
grep "LocalDataBase" conf.conf.txt | grep -v "^ *#"
??? grep -v "^ *#"
That means: don't show (-v) the lines, containing:
^ : the start of the line
* : a possible list of space characters
# : a hash character
Once you have your line, you need to work with it:
You only need the part behind the equality sign, so let's use that sign as a delimiter and show the second column:
cut -d '=' -f 2
All together:
grep "LocalDataBase" conf.conf.txt | grep -v "^ *#" | cut -d '=' -f 2
Are we there yet?
No, because it's possible that somebody has put some comment behind your entry, something like:
LocalDataBase=mydb #some information
In order to prevent that, you need to cut that comment too, which you can do in a similar way as before: this time you use the hash character as a delimiter and you show the first column:
grep "LocalDataBase" conf.conf.txt | grep -v "^ *#" | cut -d '=' -f 2 | cut -d '#' -f 1
Have fun.
You may use this sed:
mydbname=$(sed -n 's/^[^#][^=]*LocalDataBase=//p' file)
echo "$mydbname"
mydb
RegEx Details:
^: Start
[^#]: Matches any character other than #
[^=]*: Matches 0 or more of any character that is not =
LocalDataBase=: Matches text LocalDataBase=
You can use
mydbname=$(sed -n 's/^Aisse\.LocalDataBase=\(.*\)/\1/p' file)
If there can be leading whitespace you can add [[:blank:]]* after ^:
mydbname=$(sed -n 's/^[[:blank:]]*Aisse\.LocalDataBase=\(.*\)/\1/p' file)
See this online demo:
#!/bin/bash
s='# Database settings
Aisse.LocalHost=localhost
Aisse.LocalDataBase=mydb
Aisse.LocalPort=5432
Aisse.LocalUser=myuser
Aisse.LocalPasswd=mypwd
# My other app settings
Aisse.NumDir=../../data/Num
Aisse.NumMobil=3000
# Log settings
#Aisse.Trace_AppliTpv=blabla1.tra
#Aisse.Trace_AppliCmp=blabla2.tra
#Aisse.Trace_AppliClt=blabla3.tra
#Aisse.Trace_LocalDataBase=blabla4.tra'
sed -n 's/^Aisse\.LocalDataBase=\(.*\)/\1/p' <<< "$s"
Output:
mydb
Details:
-n - suppresses default line output in sed
^[[:blank:]]*Aisse\.LocalDataBase=\(.*\) - a regex that matches the start of a string (^), then zero or more whiespaces ([[:blank:]]*), then a Aisse.LocalDataBase= string, then captures the rest of the line into Group 1
\1 - replaces the whole match with the value of Group 1
p - prints the result of the successful substitution.
I have followed the example from Casey's Conky Reference with Examples
.
I modified it to have
[conky config section]
-- Format the storage information the same way for every device. Parameters: [human name] [path]
template3 = "\\1 [${fs_size \\2} ${fs_type \\2}]${alignr}${fs_used \\2} used ${fs_bar 10,60 \\2}\n${alignr}${voffset -15}${fs_used_perc \\2}%\nMount=${color3}\\2$color",
[conky TEXT section]
${execpi 60 df -h -t ext4 -t vfat -t fuse.sshfs -t fuseblk -t hfsplus --output=source,target | grep -ve "boot" -ve "nvme0" -ve "sda" | grep '^/dev/' | cut --characters=6- | sed 's/^/\$\{template3 /;s/$/\}/'}
which is working.
I would like to separate out the name of the USB device and display it, instead of displaying the entire path of the mount point.
So, I have tried the lines below:
[conky config section]
template3 = "\\1 [${fs_size \\2} ${fs_type \\2}]${alignr}${fs_used \\2} used ${fs_bar 10,60 \\2}\n${alignr}${voffset -15}${fs_used_perc \\2}%\nName=${color3}\\$color",
[conky TEXT section]
${execpi 60 df -h -t ext4 -t vfat -t fuse.sshfs -t fuseblk -t hfsplus --output=source,target | grep -ve "boot" -ve "nvme0" -ve "sda" | grep '^/dev/' | awk -F/ '{printf "%s\t%s\n", $0, $NF}' | cut --characters=6- | sed 's/^/\$\$\{template3 /;s/$/$/\}/'}
I don't know how to get that to work, maybe because I am not very good with sed.
You need to add a 3rd argument to the template, and refer to it with \\3. So you change it to:
template3 = "...Name=${color3}\\3$color"
This 3rd argument must be separated by spaces when the template is actually used, not by the tab \t you have used in the added awk. You didn't need to change the sed, which just surrounds the output with ${template3 ... }.
Instead of mixing grep, awk, and sed, you can do it all in awk more easily. Try:
${execpi 60 df -h -t ext4 -t vfat -t fuse.sshfs -t fuseblk \
-t hfsplus --output=source,target |
awk -F/ '/boot|nvme0|sda/{ next }
$0 ~ "^/dev/" { printf "${template3 %s %s}\n",substr($0,6),$NF }'}
The original grep -ve "boot" means match lines not containing "boot". The awk equivalent would be /boot/{ next }, that is: if you match the regular expression "boot" in the input line, just go on to handle the next input line instead. The regular expression /boot|nvme0|sda/ means boot or nvme0 or sda.
The original grep '^/dev/' uses a regular expression which means only match lines beginning (^) with /dev/. The awk equivalent can be /^\/dev\//{print}, but since regular expressions must be in // this means you need to escape the / and can be a bit less readable than the alternative:
$0 ~ "^/dev/" {....}, where $0 is the whole line, ~ means match, and you can use a string in quotes as a regular expression.
The original cut ... means from the 6th character, and awk has a function substr(string, start, length) to make a sub-string that can do that. If no length is given, the whole of the rest of the string is returned.
You are allowed newlines in ${exec} forms, but you must be careful with templates: use an artifice to ensure ${template3 never occurs in the string. Here I used $\{.
I want to make a script that is looking for special numbers.
numbers like this 153 = 1^3+5^3+3^3
bash script 153 3
153
In my script I have this kinda thing
echo "$1" | tr -d " " | sed -e 's/\([[:digit:]]\)/\1+/g' | tr '+' '^"$2"+'
That last command doesn't work, it does change something, it changes 1+5+3+ to 1^+5^+3^+
So my question is: how can I use variables in tr?
tr replaces one character with another one. It can't replace one character with a longer string. That's sed's job:
set -- 153 3
echo "$1" | \
tr -d " " | \
sed -e 's/\([[:digit:]]\)/\1^'"$2"'+/g; s/\+$//'
The answer by choroba is correct. Here is a python based one-liner:
$ set -- 153 3
$ python -c "print '+'.join([x+'^$2' for x in list('$1')])"
1^3+5^3+3^3
Explanation:
list will convert the string "153" to ['1', '5', '3']
[ x+'^$2' for x in <list> ] is called list comprehension. Effectively it returns another list: ['1^3', '5^3', '3^3']
Then join them with '+'
NOTE: Only reason I added this answer was because, this does not require to adjust the completed string after processing by build-in functions.
Below are the other common approaches:
$ python -c "print '^$2+'.join(list('$1')) + '^$2'" # Add "^3" after join returns "1^3+5^3+3"
$ echo $1 | sed "s/./&^$2+/g; s/+$//" # Remove last '+' sign from "1^3+5^3+3^3+"
I want to write a small script to generate the location of a file in an NGINX cache directory.
The format of the path is:
/path/to/nginx/cache/d8/40/32/13febd65d65112badd0aa90a15d84032
Note the last 6 characters: d8 40 32, are represented in the path.
As an input I give the md5 hash (13febd65d65112badd0aa90a15d84032) and I want to generate the output: d8/40/32/13febd65d65112badd0aa90a15d84032
I'm sure sed or awk will be handy, but I don't know yet how...
This awk can make it:
awk 'BEGIN{FS=""; OFS="/"}{print $(NF-5)$(NF-4), $(NF-3)$(NF-2), $(NF-1)$NF, $0}'
Explanation
BEGIN{FS=""; OFS="/"}. FS="" sets the input field separator to be "", so that every char will be a different field. OFS="/" sets the output field separator as /, for print matters.
print ... $(NF-1)$NF, $0 prints the penultimate field and the last one all together; then, the whole string. The comma is "filled" with the OFS, which is /.
Test
$ awk 'BEGIN{FS=""; OFS="/"}{print $(NF-5)$(NF-4), $(NF-3)$(NF-2), $(NF-1)$NF, $0}' <<< "13febd65d65112badd0aa90a15d84032"
d8/40/32/13febd65d65112badd0aa90a15d84032
Or with a file:
$ cat a
13febd65d65112badd0aa90a15d84032
13febd65d65112badd0aa90a15f1f2f3
$ awk 'BEGIN{FS=""; OFS="/"}{print $(NF-5)$(NF-4), $(NF-3)$(NF-2), $(NF-1)$NF, $0}' a
d8/40/32/13febd65d65112badd0aa90a15d84032
f1/f2/f3/13febd65d65112badd0aa90a15f1f2f3
With sed:
echo '13febd65d65112badd0aa90a15d84032' | \
sed -n 's/\(.*\([0-9a-f]\{2\}\)\([0-9a-f]\{2\}\)\([0-9a-f]\{2\}\)\)$/\2\/\3\/\4\/\1/p;'
Having GNU sed you can even simplify the pattern using the -r option. Now you won't need to escape {} and () any more. Using ~ as the regex delimiter allows to use the path separator / without need to escape it:
sed -nr 's~(.*([0-9a-f]{2})([0-9a-f]{2})([0-9a-f]{2}))$~\2/\3/\4/\1~p;'
Output:
d8/40/32/13febd65d65112badd0aa90a15d84032
Explained simple the pattern does the following: It matches:
(all (n-5 - n-4) (n-3 - n-2) (n-1 - n-0))
and replaces it by
/$1/$2/$3/$0
You can use a regular expression to separate each of the last 3 bytes from the rest of the hash.
hash=13febd65d65112badd0aa90a15d84032
[[ $hash =~ (..)(..)(..)$ ]]
new_path="/path/to/nginx/cache/${BASH_REMATCH[1]}/${BASH_REMATCH[2]}/${BASH_REMATCH[3]}/$hash"
Base="/path/to/nginx/cache/"
echo '13febd65d65112badd0aa90a15d84032' | \
sed "s|\(.*\(..\)\(..\)\(..\)\)|${Base}\2/\3/\4/\1|"
# or
# sed sed 's|.*\(..\)\(..\)\(..\)$|${Base}\1/\2/\3/&|'
Assuming info is a correct MD5 (and only) string
First of all - thanks to all of the responders - this was extremely quick!
I also did my own scripting meantime, and came up with this solution:
Run this script with a parameter of the URL you're looking for (www.example.com/article/76232?q=hello for example)
#!/bin/bash
path=$1
md5=$(echo -n "$path" | md5sum | cut -f1 -d' ')
p3=$(echo "${md5:0-2:2}")
p2=$(echo "${md5:0-4:2}")
p1=$(echo "${md5:0-6:2}")
echo "/path/to/nginx/cache/$p1/$p2/$p3/$md5"
This assumes the NGINX cache has a key structure of 2:2:2.