I'm using a bash script to grep out some lines from a log file. The basic format of this log file is:
field1: value1, field2=value2, field3=value3,
field4=value4,value5,value6, field5=value7
Sometimes there will be lines in which field1: value1 is identical, but some of the other information is either the same or different. I'd like to filter those lines out, so that I only grep out the first instance of anything that has the same "field1: value1" tuple.
I'd prefer a nice command-line one-liner if you can find something especially simple. I definitely want to keep it in the bash script. This is on linux, so we've got all the command-line tools available.
Thanks!
Using awk:
awk -F, '!arr[$1]++ { print }' LOGFILE
The awk program uses an array to keep a count of the number of times a particular 'field1: value1` string is seen, but only prints the incoming line the first time.
Related
I have the following awk command to join lines which are smaller than a limit (it is basically used to break lines in multiline fixed-width file):
awk 'last{$0=last $0;} length($0)<21{last=$0" ";next} {print;last=""}' input_file.txt > output_file.txt
input_file.txt:
1,11,"dummy
111",1111
2,22,"dummy 222",2222
3,33,"dummy 333",3333
output_file.txt (expected):
1,11,"dummy 111",1111
2,22,"dummy 222",2222
3,33,"dummy 333",3333
The script works pretty well with small files (~MB) but it does nothing with big files (~GB).
What may be the problem?
Thanks in advance.
Best guess - all the lines in your big file are longer than 21 chars. There are more robust ways to do what you're trying to do with that script, though, so it may not be worth debugging this and ask for help with an improved script instead.
Here's one more robust way to combine quoted fields that contain newlines using any awk:
$ awk -F'"' '{$0=prev $0; if (NF%2){print; prev=""} else prev=$0 OFS}' input_file.txt
1,11,"dummy 111",1111
2,22,"dummy 222",2222
3,33,"dummy 333",3333
That may be a better starting point for you than your existing script. To do more than that, see What's the most robust way to efficiently parse CSV using awk?.
I have been working on this little script at work to free up my own time and am currently stuck on part of it. The script is supposed to pull some content from a JSON, modify the content, and then re-upload it. The modification part is the portion that doesn't work.
An example of what the content looks like after being extracted from the JSON is:
<p>App1_v1.0_20160911_release.apk</p<p>App2_v2.0_20160915_beta.apk</p><p>App3_v3.0_20150909_VendorRelease.apk</p>
The modification function is supposed to update the list with the newer app filenames in the same location. I've tried using both SED and AWK to get this to work but I haven't gotten anywhere fast.
Here are examples of both commands and the parameters for the substitution I am trying to run on the example file:
old_name=App1_.*_release.apk
new_name=App1_v1.0_20160920_1152_release.apk
sed "s/$old_name/$new_name/" body > upload
awk -v oldname="$old_name" -v newname="$new_name" '{sub(oldname, newname)}1' body > upload
What ends up happening is the substitution will change the correct part of the list, but then nuke everything between that point and the end of the list.
Thank you for any and all help.
PS: If I didn't explain something correctly or you feel some information is missing, please comment and let me know so I can better explain the problem.
There are SO many possible values of oldname, newname, and your input data that could cause either of the commands you wrote to fail - don't use that "replace a regexp with a backreference-enabled-string" approach in any command, use string operations instead (which means you can't use sed since sed doesn't support strings)
This modifies your sample input as you say you want:
$ awk -v new='App1_v1.0_20160920_1152_release.apk' 'BEGIN{RS="</p>\n?"; FS=OFS="<p>"} NR==1{$2=new} {printf "%s%s", $0, RT}' file
<p>App1_v1.0_20160920_1152_release.apk<p>App2_v2.0_20160915_beta.apk</p><p>App3_v3.0_20150909_VendorRelease.apk</p>
If that's not adequate then edit your question to better explain your requirements and provide more truly representative sample input/output.
The above uses GNU awk for multi-char RS and RT.
I have a parsed content similar to this as a output from JSON.sh.
["/home/ukrishnan/projects/test.yml","LOG_DRIVER"] "syslog"
["/home/ukrishnan/projects/test.yml","IMAGE"] "mysql:5.6"
["/home/ukrishnan/projects/test.yml"] {"LOG_DRIVER":"syslog","IMAGE":"mysql:5.6"}
["/home/ukrishnan/projects/mysql/app.xml","ENV_ACCOUNT_BRIDGE_ENDPOINT"] "/u01/src/test/sample.txt"
["/home/ukrishnan/projects/mysql/app.xml"] {"ENV_ACCOUNT_BRIDGE_ENDPOINT":"/u01/src/test/sample.txt"}
[] {"/home/ukrishnan/projects/test.yml":{"LOG_DRIVER":"syslog","IMAGE":"mysql:5.6"},"/home/ukrishnan/projects/mysql/app.xml":{"ENV_ACCOUNT_BRIDGE_ENDPOINT":"/u01/src/test/sample.txt"}}
So, I just wanted to take the values, similar to the Line 1,2 and 4. And need to parse, for example in the first line, "/home/ukrishnan/projects/test.yml","LOG_DRIVER","syslog" for all the lines with similar format. Please help as I'm completely a newbie to grep or awk.
Edit:
Sorry, if this is two broad. Here is what I tried.
By using, grep -v "{\|}" returns,
["/home/ukrishnan/projects/test.yml","LOG_DRIVER"] "syslog"
["/home/ukrishnan/projects/test.yml","IMAGE"] "mysql:5.6"
["/home/ukrishnan/projects/mysql/app.xml","ENV_ACCOUNT_BRIDGE_ENDPOINT"] "/u01/src/test/sample.txt"
If someone helps me with also grabbing values within double quotes in a single grep, that would be great.
this one-liner works for your example:
awk '$NF~/^[^{]/&&sub(/^\[/,"")+sub(/\]\s*/,",")' file
It gives:
"/home/ukrishnan/projects/test.yml","LOG_DRIVER","syslog"
"/home/ukrishnan/projects/test.yml","IMAGE","mysql:5.6"
"/home/ukrishnan/projects/mysql/app.xml","ENV_ACCOUNT_BRIDGE_ENDPOINT","/u01/src/test/sample.txt"
I have a CSV file with several thousand lines, and I need to take some of the columns in that file to create another CSV file to use for import to a database.
I'm not in shape with shell scripting anymore, is there anyone who can help with pointing me in the correct direction?
I have a bash script to read the source file but when I try to print the columns I want to a new file it just doesn't work.
while IFS=, read symbol tr_ven tr_date sec_type sec_name name
do
echo "$name,$name,$symbol" >> output.csv
done < test.csv
Above is the code I have. Out of the 6 columns in the original file, I want to build a CSV with "column6, column6, collumn1"
The test CSV file is like this:
Symbol,Trading Venue,Trading Date,Security Type,Security Name,Company Name
AAAIF,Grey Market,22/01/2015,Fund,,Alternative Investment Trust
AAALF,Grey Market,22/01/2015,Ordinary Shares,,Aareal Bank AG
AAARF,Grey Market,22/01/2015,Ordinary Shares,,Aluar Aluminio Argentino S.A.I.C.
What am I doing wrong with my script? Or, is there an easier - and faster - way of doing this?
Edit
These are the real headers:
Symbol,US Trading Venue,Trading Date,OTC Tier,Caveat Emptor,Security Type,Security Class,Security Name,REG_SHO,Rule_3210,Country of Domicile,Company Name
I'm trying to get the last column, which is number 12, but it always comes up empty.
The snippet looks and works fine to me, maybe you have some weird characters in the file or it is coming from a DOS environment (use dos2unix to "clean" it!). Also, you can make use of read -r to prevent strange behaviours with backslashes.
But let's see how can awk solve this even faster:
awk 'BEGIN{FS=OFS=","} {print $6,$6,$1}' test.csv >> output.csv
Explanation
BEGIN{FS=OFS=","} this sets the input and output field separators to the comma. Alternatively, you can say -F=",", -F, or pass it as a variable with -v FS=",". The same applies for OFS.
{print $6,$6,$1} prints the 6th field twice and then the 1st one. Note that using print, every comma-separated parameter that you give will be printed with the OFS that was previously set. Here, with a comma.
I have data in zdt format (like this), where I want to perform this python script only on the third column (the pinyin one). I have tried to do this with sed and awk but I have not had any success due to my limited knowledge of these tools. Ideally, I want to feed the column’s contents to the python script and then have the source replaced with the yield of the script.
This is roughly what I envision but the call is not executed, not even when in quotes.
s/([a-z]+[1,2,3,4]?)(?=.*\t)/decode_pinyin(\1)/g
I am not too strict of the tools (sed, awk, python, …) used, I just want a shell script for batch processing of a number of files. It would be best if the original spaces are preserved.
Try something like this:
awk -F'\t' '{printf "decode_pinyin(\"%s\")\n", $3}' file
This outputs:
decode_pinyin("ru4xiang1 sui2su2")
decode_pinyin("ru4")
decode_pinyin("xiang1")
decode_pinyin("sui2")
decode_pinyin("su2")