I've been trying to make tail a little more readable for server startups. My current command filters out most of the INFO and DEBUG messages from the startup:
tail -F ../server/durango/log/server.log | grep -e "ERROR" -e "WARN" -e "Shutdown" -e "MicroKernel" | grep --color=auto -E 'MicroKernel|$'
What I would like to do is craft something that would highlight WARN in yellow and ERROR in red, and MicroKernel in green. I tried just piping grep --color=auto multiple times, but the only color that survives is the last command in the pipe.
Is there a one liner to do this? Or even a many-liner?
yes, there is way to do this. That is, as long as your terminal supports ANSI escape sequences. This is most terminals that exist.
I think I don't need explain how to grep, sed etc. point is the color right?
see below, this will make
WARN yellow
ERROR red
foo green
here is example:
kent$ echo "WARN
ERROR
foo"|sed 's#WARN#\x1b[33m&#; s#ERROR#\x1b[31m&#; s#foo#\x1b[32m&#'
Note: \x1b is hexadecimal for the ESC character (^VEsc).
to see the result:
I wrote a script for this years ago. You can easily cover the case of multiple colors by piping successive invocations of highlight to each other.
From the README:
Usage: ./highlight [-i] [--color=COLOR_STRING] [--] <PATTERN0> [PATTERN1...]
This is highlight version 1.0.
This program takes text via standard input and outputs it with the given
perlre(1) pattern(s) highlighted with the given color. If no color option
is specified, it defaults to 'bold red'. Colors may be anything
that Perl's Term::ANSIColor understands. This program is similar to
"grep --color PATTERN" except both matching and non-matching lines are
printed.
The default color can be selected via the $HIGHLIGHT_COLOR environment
variable. The command-line option takes precedence.
Passing -i or --ignore-case will enable case-insensitive matching.
If your pattern begins with a dash ('-'), you can pass a '--' argument
after any options and before your pattern to distinguish it from an
option.
I have been using a tool called grc for this for years. works like a charm. It comes with some quite good templates for many standard log outputs and formats and it is easy to define your own.
A command I use often is
grc tail -f /var/log/syslog
It colorizes the syslog output so it is easy to spot errors (typically marked red.
Find the tool here:
https://github.com/garabik/grc
(it is also available as package for most common linux flavours).
I wrote TxtStyle, a small utility for colorising logs. You define regular expressions to highlight in ~/.txts.conf file:
[Style="example"]
!red: regex("error")
green: regex("\d{4}-\d\d-\d\d")
# ...
And then apply the styles:
txts -n example example.log
or you can also pipe the output
tail -f example.log | txts -n example
You can create a colored log instead of using a complex command.
For php is like this:
echo "^[[30;43m".$ip."^[[0m";
The key point is to use Ctrl-v ctrl-[ to input a green ^[ under insert mode in vim, direct input ^[ does not work.
More info here
My sample using awk. Match log format like: xxxx [debug] xxxxx xxxx xxxx
black=30m
red=31m
green=32m
yellow=33m
blue=34m
magenta=35m
cyan=36m
white=37m
blacklog="\"\033[$black\" \$0 \"\033[39m\""
redlog="\"\033[$red\" \$0 \"\033[39m\""
greenlog="\"\033[$green\" \$0 \"\033[39m\""
yellowlog="\"\033[$yellow\" \$0 \"\033[39m\""
bluelog="\"\033[$blue\" \$0 \"\033[39m\""
magentalog="\"\033[$magenta\" \$0 \"\033[39m\""
cyanlog="\"\033[$cyan\" \$0 \"\033[39m\""
whitelog="\"\033[$white\" \$0 \"\033[39m\""
trace="/\[trace\]/ {print $redlog}"
debug="/\[debug\]/ {print $magentalog}"
info="/\[info\]/ {print $greenlog}"
warning="/\[warning\]/ {print $bluelog}"
error="/\[error\]/ {print $yellowlog}"
yourcommand | awk "$trace $debug $info $warning $error"
Related
Is there a way to make grep output "words" from files that match the search expression?
If I want to find all the instances of, say, "th" in a number of files, I can do:
grep "th" *
but the output will be something like (bold is by me);
some-text-file : the cat sat on the mat
some-other-text-file : the quick brown fox
yet-another-text-file : i hope this explains it thoroughly
What I want it to output, using the same search, is:
the
the
the
this
thoroughly
Is this possible using grep? Or using another combination of tools?
Try grep -o:
grep -oh "\w*th\w*" *
Edit: matching from Phil's comment.
From the docs:
-h, --no-filename
Suppress the prefixing of file names on output. This is the default
when there is only one file (or only standard input) to search.
-o, --only-matching
Print only the matched (non-empty) parts of a matching line,
with each such part on a separate output line.
Cross distribution safe answer (including windows minGW?)
grep -h "[[:alpha:]]*th[[:alpha:]]*" 'filename' | tr ' ' '\n' | grep -h "[[:alpha:]]*th[[:alpha:]]*"
If you're using older versions of grep (like 2.4.2) which do not include the -o option, then use the above. Else use the simpler to maintain version below.
Linux cross distribution safe answer
grep -oh "[[:alpha:]]*th[[:alpha:]]*" 'filename'
To summarize: -oh outputs the regular expression matches to the file content (and not its filename), just like how you would expect a regular expression to work in vim/etc... What word or regular expression you would be searching for then, is up to you! As long as you remain with POSIX and not perl syntax (refer below)
More from the manual for grep
-o Print each match, but only the match, not the entire line.
-h Never print filename headers (i.e. filenames) with output lines.
-w The expression is searched for as a word (as if surrounded by
`[[:<:]]' and `[[:>:]]';
The reason why the original answer does not work for everyone
The usage of \w varies from platform to platform, as it's an extended "perl" syntax. As such, those grep installations that are limited to work with POSIX character classes use [[:alpha:]] and not its perl equivalent of \w. See the Wikipedia page on regular expression for more
Ultimately, the POSIX answer above will be a lot more reliable regardless of platform (being the original) for grep
As for support of grep without -o option, the first grep outputs the relevant lines, the tr splits the spaces to new lines, the final grep filters only for the respective lines.
(PS: I know most platforms by now would have been patched for \w.... but there are always those that lag behind)
Credit for the "-o" workaround from #AdamRosenfield answer
It's more simple than you think. Try this:
egrep -wo 'th.[a-z]*' filename.txt #### (Case Sensitive)
egrep -iwo 'th.[a-z]*' filename.txt ### (Case Insensitive)
Where,
egrep: Grep will work with extended regular expression.
w : Matches only word/words instead of substring.
o : Display only matched pattern instead of whole line.
i : If u want to ignore case sensitivity.
You could translate spaces to newlines and then grep, e.g.:
cat * | tr ' ' '\n' | grep th
Just awk, no need combination of tools.
# awk '{for(i=1;i<=NF;i++){if($i~/^th/){print $i}}}' file
the
the
the
this
thoroughly
grep command for only matching and perl
grep -o -P 'th.*? ' filename
I was unsatisfied with awk's hard to remember syntax but I liked the idea of using one utility to do this.
It seems like ack (or ack-grep if you use Ubuntu) can do this easily:
# ack-grep -ho "\bth.*?\b" *
the
the
the
this
thoroughly
If you omit the -h flag you get:
# ack-grep -o "\bth.*?\b" *
some-other-text-file
1:the
some-text-file
1:the
the
yet-another-text-file
1:this
thoroughly
As a bonus, you can use the --output flag to do this for more complex searches with just about the easiest syntax I've found:
# echo "bug: 1, id: 5, time: 12/27/2010" > test-file
# ack-grep -ho "bug: (\d*), id: (\d*), time: (.*)" --output '$1, $2, $3' test-file
1, 5, 12/27/2010
cat *-text-file | grep -Eio "th[a-z]+"
You can also try pcregrep. There is also a -w option in grep, but in some cases it doesn't work as expected.
From Wikipedia:
cat fruitlist.txt
apple
apples
pineapple
apple-
apple-fruit
fruit-apple
grep -w apple fruitlist.txt
apple
apple-
apple-fruit
fruit-apple
I had a similar problem, looking for grep/pattern regex and the "matched pattern found" as output.
At the end I used egrep (same regex on grep -e or -G didn't give me the same result of egrep) with the option -o
so, I think that could be something similar to (I'm NOT a regex Master) :
egrep -o "the*|this{1}|thoroughly{1}" filename
To search all the words with start with "icon-" the following command works perfect. I am using Ack here which is similar to grep but with better options and nice formatting.
ack -oh --type=html "\w*icon-\w*" | sort | uniq
You could pipe your grep output into Perl like this:
grep "th" * | perl -n -e'while(/(\w*th\w*)/g) {print "$1\n"}'
grep --color -o -E "Begin.{0,}?End" file.txt
? - Match as few as possible until the End
Tested on macos terminal
$ grep -w
Excerpt from grep man page:
-w: Select only those lines containing matches that form whole words. The test is that the matching substring must either be at the beginning of the line, or preceded by a non-word constituent character.
ripgrep
Here are the example using ripgrep:
rg -o "(\w+)?th(\w+)?"
It'll match all words matching th.
I have to filter a very verbose log output that the only pattern between messages for warning or errors is the output text color
Is there a way to filter by the output color when using grep?
When I try to use the color code I have an error due to the [
$ echo -e "Default \e[94mLight blue" | grep \e[94m
grep: brackets ([ ]) not balanced
I managed to be able to filter it by using just <number color>m
echo -e "Default \e[94mLight blue" | grep 94m
Default 94mLight blue
But it removes all color formatting, changes the output and also has the potential to match a lot of other text that is not just color formatting.
How can I accomplish it?
There are several places where this goes wrong:
The character [ has a special meaning for grep, unless you use the --fixed-strings (-F in short) option. So it needs to be quoted:
grep '\[94m'
There is also (seems to be?) no way to specify the Escape character (\e) directly for grep with \e, \033 or something similar. But you can use zsh's $'…' quoting to let zsh create the Escape character:
grep $'\e\\[94m'
Strings inside $'…' will be process like arguments to the print builtin. So \e will be replaced by the actual Escape character and \ needs to be doubled in order to get a single, quoted backslash.
Be sure to use grep without any options that change formatting, for example --color=auto. By default Oh-My-Zsh creates an alias named grep that includes this option, if it is available.
You can force zsh to use the command instead of an alias by prepending the command precommand modifier:
command grep
All in all the following command should do the trick:
echo -e "Default \e[94mLight blue" | command grep $'\e\\[94m'
Note 1: This requires zsh due to $'…'. A more portable version would be
echo -e "Default \e[94mLight blue" | command grep $(printf '\033\\[94m')
Note 2: Unless the log output sets color codes (also) at the beginning of each line or resets them at the end of the line, the coloration of the output may still be broken. In that case you may have to use awk in order to get a better result:
echo "Default \e[94mLight blue\nDefault \e[94mLight blue" |
awk '/\033\[94m/ {printf "%s\033[0m\n", $0}'
This appends the reset coder \e[0m to the end of each matching line when printing it. Note that awk (at least the GNU version) does not use \e to signifiy the Escape character, you have to use 033 instead.
You can check, whether grep is an alias with this command:
whence -v grep
It is also possible that the environment variable GREP_OPTIONS is set to include such options. To check this, you can run this command:
echo "${(t)GREP_OPTIONS}: $GREP_OPTIONS}"
This shows the type of GREP_OPTIONS followed by its value (type: value). If the type does not contain export or the value is empty there should be no problem.
You can try this
echo -e "Default \e[94mLight blue" | sed -n '/\[94m/p'
This printed colors for me in zsh. I couldn't manage to include the '\e'
I'm wanting to use the grep in a bash script to find matching lines in a file, highlight the matches with color, and then print out the results in a table using the column command. Something like this:
data=`cat file.data | egrep -i --color "$search"`
echo $'\n'"col1"$'\t'"col2"$'\t'"col3"$'\t'"col4"$'\n'"$data" | column -t -s$'\t'
The above code does everything as desired, except that the color is lost.
Here's a simplified example:
As you can see, when I used grep the results were printed on individual lines and in color, but when I save the results to a variable and then print the variable out, the line breaks and colors are gone.
Is there any way to do what I'm asking?
Use the option --color=always:
data=$(egrep -i --color=always "$search" file.data)
By default, grep does not produce color unless the output is going directly to a terminal. This is normally a good thing. The option --color=always overrides that.
For occasions when you don't want color, use --color=never.
This question already has answers here:
Colorized grep -- viewing the entire file with highlighted matches
(24 answers)
Closed 7 years ago.
When using grep, it will highlight any text in a line with a match to your regular expression.
What if I want this behaviour, but have grep print out all lines as well? I came up empty after a quick look through the grep man page.
Use ack. Checkout its --passthru option here: ack. It has the added benefit of allowing full perl regular expressions.
$ ack --passthru 'pattern1' file_name
$ command_here | ack --passthru 'pattern1'
You can also do it using grep like this:
$ grep --color -E '^|pattern1|pattern2' file_name
$ command_here | grep --color -E '^|pattern1|pattern2'
This will match all lines and highlight the patterns. The ^ matches every start of line, but won't get printed/highlighted since it's not a character.
(Note that most of the setups will use --color by default. You may not need that flag).
You can make sure that all lines match but there is nothing to highlight on irrelevant matches
egrep --color 'apple|' test.txt
Notes:
egrep may be spelled also grep -E
--color is usually default in most distributions
some variants of grep will "optimize" the empty match, so you might want to use "apple|$" instead (see: https://stackoverflow.com/a/13979036/939457)
EDIT:
This works with OS X Mountain Lion's grep:
grep --color -E 'pattern1|pattern2|$'
This is better than '^|pattern1|pattern2' because the ^ part of the alternation matches at the beginning of the line whereas the $ matches at the end of the line. Some regular expression engines won't highlight pattern1 or pattern2 because ^ already matched and the engine is eager.
Something similar happens for 'pattern1|pattern2|' because the regex engine notices the empty alternation at the end of the pattern string matches the beginning of the subject string.
[1]: http://www.regular-expressions.info/engine.html
FIRST EDIT:
I ended up using perl:
perl -pe 's:pattern:\033[31;1m$&\033[30;0m:g'
This assumes you have an ANSI-compatible terminal.
ORIGINAL ANSWER:
If you're stuck with a strange grep, this might work:
grep -E --color=always -A500 -B500 'pattern1|pattern2' | grep -v '^--'
Adjust the numbers to get all the lines you want.
The second grep just removes extraneous -- lines inserted by the BSD-style grep on Mac OS X Mountain Lion, even when the context of consecutive matches overlap.
I thought GNU grep omitted the -- lines when context overlaps, but it's been awhile so maybe I remember wrong.
You can use my highlight script from https://github.com/kepkin/dev-shell-essentials
It's better than grep cause you can highlight each match with it's own color.
$ command_here | highlight green "input" | highlight red "output"
Since you want matches highlighted, this is probably for human consumption (as opposed to piping to another program for instance), so a nice solution would be to use:
less -p <your-pattern> <your-file>
And if you don't care about case sensitivity:
less -i -p <your-pattern> <your-file>
This also has the advantage of having pages, which is nice when having to go through a long output
You can do it using only grep by:
reading the file line by line
matching a pattern in each line and highlighting pattern by grep
if there is no match, echo the line as is
which gives you the following:
while read line ; do (echo $line | grep PATTERN) || echo $line ; done < inputfile
If you want to print "all" lines, there is a simple working solution:
grep "test" -A 9999999 -B 9999999
A => After
B => Before
If you are doing this because you want more context in your search, you can do this:
cat BIG_FILE.txt | less
Doing a search in less should highlight your search terms.
Or pipe the output to your favorite editor. One example:
cat BIG_FILE.txt | vim -
Then search/highlight/replace.
If you are looking for a pattern in a directory recursively, you can either first save it to file.
ls -1R ./ | list-of-files.txt
And then grep that, or pipe it to the grep search
ls -1R | grep --color -rE '[A-Z]|'
This will look of listing all files, but colour the ones with uppercase letters. If you remove the last | you will only see the matches.
I use this to find images named badly with upper case for example, but normal grep does not show the path for each file just once per directory so this way I can see context.
Maybe this is an XY problem, and what you are really trying to do is to highlight occurrences of words as they appear in your shell. If so, you may be able to use your terminal emulator for this. For instance, in Konsole, start Find (ctrl+shift+F) and type your word. The word will then be highlighted whenever it occurs in new or existing output until you cancel the function.
I'd like to know if I can colour highlight the output of a shell command that matches certain strings.
For example, if I run myCommand, with the output below:
> myCommand
DEBUG foo bar
INFO bla bla
ERROR yak yak
I'd like all lines matching ^ERROR\s.* to be highlighted red.
Similarly, I'd like the same highlighting to be applied to the output of grep, less etc...
EDIT: I probably should mention that ideally I'd like to enable this feature globally via a 'profile' option in my .bashrc.
There is an answer in superuser.com:
your-command | grep -E --color 'pattern|$'
or
your-command | grep --color 'pattern\|$'
This will "match your pattern or the end-of-line on each line. Only the pattern is highlighted..."
You can use programs such as:
spc (Supercat)
grc (Generic Colouriser)
highlight
histring
pygmentize
grep --color
You can do something like this, but the commands won't see a tty (some will refuse to run or behave differently or do weird things):
exec > >(histring -fEi error) # Bash
If you want to enable this globally, you'll want a terminal feature, not a process that you pipe output into, because a pipe would be disruptive to some command (two problems are that stdout and stderr would appear out-of-order and buffered, and that some commands just behave differently when outputting to a terminal).
I don't know of any “conventional” terminal with this feature. It's easily done in Emacs, in a term buffer: configure font-lock-keywords for term-mode.
However, you should think carefully whether you really want that feature all the time. What if the command has its own colors (e.g. grep --color, ls --color)? Maybe it would be better to define a short alias to a colorizer command and run myCommand 2>&1|c when you want to colorize myCommand's output. You could also alias some specific always-colorize commands.
Note that the return status of a pipeline is its last command, so if you run myCommand | c, you'll get the status of c, not myCommand. Here's a bash wrapper that avoids this problem, which you can use as w myCommand:
w () {
"$#" | c
return $PIPESTATUS[0]
}
You could try (maybe needs a bit more escaping):
BLUE="$(tput setaf 4)"
BLACK="$(tput sgr0)"
command | sed "s/^ERROR /${BLUE}ERROR ${BLACK}/g"
Try
tail -f yourfile.log | egrep --color 'DEBUG|'
where DEBUG is the text you want to highlight.
You can use the hl command avalaible on github :
git clone http://github.com/mbornet-hl/hl
Then :
myCommand | hl -r '^ERROR.*'
You can use the $HOME/.hl.cfg configuration file to simplify the command line.
hl is written in C (source is available).
You can use up to 42 differents colors of text.
Use awk.
COLORIZE_AWK_COMMAND='{ print $0 }'
if [ -n "$COLORIZE" ]; then
COLORIZE_AWK_COMMAND='
/pattern1/ { printf "\033[1;30m" }
/pattern2/ { printf "\033[1;31m" }
// { print $0 "\033[0m"; }'
fi
then later you can pipe your output
... | awk "$COLORIZE_AWK_COMMAND"
printf is used in the patterns so we don't print a newline, just set the color.
You could probably enable it for specific commands using aliases and user defined shell functions wihtout too much trouble. If your coloring errors I assume you want to process stderr. Since stderr in unbuffered you would probably want to line buffer it by sending through a fifo.