Grep / awk greater than date

Question

I'm sure this is an easy one for the Gurus. I'm working on my get things done and todo system. At the moment I've simply got a markdown file which I edit in VI and set tags against my things to do.

It looks like this

# My project | @home
- Do this this | @home

I think sync this file across my devices and use tasker / grep on android to show me the todo based on where I am.

I've now got to the stage where I want to add things to do in the future so I was thinking of something like

- Do this thing in the future | @home @2014-02-01

How could I exclude that line until the date is 2014-02-01? My current command for just extract @home todos is

grep -e "@home" myfile | cut -d '|' -f1

I'm convinced there's a way of doing this, but google / stackoverflow hasn't lead me the right direction yet!

Help appreciated,

Thanks

Alan

Answer 1

Using awk:

DAT=$(date +%Y%m%d)    # get today's date, for example 20140117
awk 'NF>3{gsub(/-/,"",$NF);if ($NF>d) next}{print $1}' FS="[|@]" d=$DAT file

# My project
- Do this this

Answer 2

Using Perl

perl -MTime::Piece -ne '
  BEGIN {$now = localtime}
  print unless /@(\d{4}-\d\d-\d\d)/ and $now < Time::Piece->strptime($1, "%Y-%m-%d")
' <<END
# My project | @home
- Do this this | @home
- Do this thing in the future | @home @2014-02-01
END

# My project | @home
- Do this this | @home

Also, GNU awk

gawk '
    BEGIN {now = systime()}
    match($0,/@([0-9][0-9][0-9][0-9])-([0-9][0-9])-([0-9][0-9])/, m) {
        time = mktime(m[1] " " m[2] " " m[3] " 0 0 0")
        if (time > now) next
    }
    1
'

Answer 3

For files that use dates in a format where the chronological order is the same as the lexical order, like nginx error log you can find the lines after a certain date using awk:

    awk -v "oneHourAgo=$(date +'%Y/%m/%d %H:%M:%S' -d '1 hour ago')" '/^[0-9]{4}\/[0-9]{2}\/[0-9]{2}/{ if ($0 >= oneHourAgo) print $0 }' /var/log/nginx/error.log

The error log might contain multiline errors that do not start with a date, so those are filtered out.