Find variable in template file replace w/date+ and save as

jmanjohn61 · 12-02-2004, 06:53 AM

I need to examine a file/template containing specific variables and replacing those variables with current date for 1/10 of the variable and tomorrows date date for another 1/10 of the variable then the day after tomorrow for the next 1/10 of the variable and so on until all 10 variables in the file have been changed. Then save the file with a new name and location.

An example file would be:

On (variable%) there will be no school. Following that day on (variable2%) you will be rsponsible for cleanup. Then on (variable3%) each student needs to place chairs in line.

(variable%) needs todays date
(variable2%) needs tomorrows date
(variable3%) needs the day after tomorrows date and so on

Does anyone have any app or cli that will allow me to read a template file looking for a variable/s and replace the variables with curernt+ dates?

Thanks for your help!

John

theYinYeti · 12-02-2004, 06:59 AM

Why would you want to write that. A more generic script would be much more usefull. Anyway, the answer is to use date to compute the dates, and sed to do the replacements.

Yves.

jmanjohn61 · 12-02-2004, 09:12 AM

I don't understand what you mean by "Why would you want to write that.".
I want something to automate date insertion at pre-determined intervals. Maybe using cron to execute...
I am looking for either an application or script.
I did look at the man pages for both date and sed and I see the potential but not the format.
Would you have something I could work with?

John

theYinYeti · 12-02-2004, 10:45 AM

Here's the program:

Code:

#!/bin/bash

declare -a MONTHS=(31 28 31 30 31 30 31 31 30 31 30 31)
DATEFORMAT=+%A-%D

function getDate() {
	local year=$(date +%Y)
	local month=$(( $(date +%m) - 1 ))
	local day=$(( $(date +%d) + $1 ))
	while [ $day -lt 1 ] || [ $day -gt ${MONTHS[$month]} ]; do
		if [ $day -lt 1 ]; then
			month=$(( $month - 1 ))
			day=$(( ${MONTHS[$month]} + $day ))
			if [ $month -lt 0 ]; then
				month=11
				year=$(( $year - 1 ))
			fi
		elif [ $day -gt ${MONTHS[$month]} ]; then
			day=$(( $day - ${MONTHS[$month]} ))
			month=$(( $month + 1 ))
			if [ $month -gt 11 ]; then
				month=0
				year=$(( $year + 1 ))
			fi
		fi
	done
	echo "$(date --date=${year}-$(( ${month} + 1 ))-${day} ${DATEFORMAT})"
}

eval echo '"'"$(sed -e 's/\([$"]\)/\\\1/g' -e 's/(DATE\([+-][0-9][0-9]*\)%)/"$(getDate \1)"/g')"'"'

And here's an example:

Code:

$ cat dates.txt | ./tdate.sh
Hello, on Thursday-12/02/04, you will go to "St John Street" and pay your book with $dolars.
Two '2' days later (it will be Saturday-12/04/04), bring the book to me.
        Bye!

with dates.txt being:

Code:

Hello, on (DATE+0%), you will go to "St John Street" and pay your book with $dolars.
Two '2' days later (it will be (DATE+2%)), bring the book to me.
        Bye!

Yves.

jmanjohn61 · 12-02-2004, 12:56 PM

WOW!
What about a different date format 2004-12-31? Leap Year?
I appreciate your time!

John

jmanjohn61 · 12-02-2004, 04:46 PM

Never mind. I did need an example and was in a rush earlier. Your solution is all that is needed. I 'man'ned each command and I can see now. Thank you Mr. Yves. Again, thank you.

R/S

John

jmanjohn61 · 12-03-2004, 09:30 AM

I have one last problem. I taylored this script to meet my needs as best I know. There are somethings in the file I apply tdate.sh that create a return upon executing =

./tdate.sh: line 1: program: command not found

I have my new date format and read through the sed command via man (what a tool). I don't know how sed reads my file to prevent this. Can you help resolve this YinYeti?

theYinYeti · 12-03-2004, 09:41 AM

I would need more details to help you. Please prepare those details over the week-end. I won't be able to help you until Monday. Bye,

Yves.

jmanjohn61 · 12-07-2004, 07:31 AM

Details.
This file is a sql insert with 'program' (table) prepending each line. The script runs successfully. The purpose of the database is to have a calendar/scheduler table auto-populate. I am making use of an existing application that would require much more change to affect what I need. I have to go a couple steps further by automatically removing old and inserting new rows created by the tdate.sh all by date. Any direction there is also appreciated. I have browsed a number of perl pages to locate what I need, no luck yet.

John

theYinYeti · 12-07-2004, 07:50 AM

I won't be able to help you in such a general way. It would take too much time. Please post a specific example: the exact thing that is run, the wanted result, the real result.

jmanjohn61 · 12-09-2004, 08:39 PM

Thanks for your help. I have more work with this in the form of a lesson.
The script you wrote only worked for a couple days as it was written for a time period. Any direction on where/what I can get to swim in script to write one that does not blowup after 5 days?

I understand only a little of sed and less of the date definitions and functions. Is there some place I can go to have someone create a script for me? Or a tool that builds?

John

theYinYeti · 12-10-2004, 01:45 AM

In truth, the way I handled the date shift is a quick hack, because the important part for your problem, as I see it, is the "eval ..." line, even though it is only one line long. AFAIK, perl or php should give you higher-level functions for shifting the date. Good luck.

jmanjohn61 · 12-10-2004, 09:20 AM

Thanks. Why then originally offer date/sed as the solution???

theYinYeti · 12-13-2004, 02:42 AM

Good question, and easy answer

bash scripting is the art of combining the right tools for each task:
- "date" is very good at giving the individual components of current date.
- "sed" is very good at replacing regular expressions with something else.

As for date-shifting, I thought at first that "date" could handle that, or maybe "cal". And when I saw that it could not, I decided that I'd quickly write a function, just for being able to run an example. Because the way I see it, the eval... line is the line you'd have had a hard time coming up with... wouldn't it?

But Linux is all about sharing knowledge

I'm just now in the process of learning PHP (that how I saw, that something could probably be done with dates using PHP), and I don't know Perl. If you solve the date-shifting part, be sure to share

Yves.

jmanjohn61 · 12-13-2004, 06:49 AM

Oh I will share. One thing for sure, the sharing did open my eyes. I've started looking into perl and realize everyday, more and more, how much I don't know. I hope to have this perl script up in a couple learning curve weeks (who knows what that is in dog years).

Happy Holidays.

John