dateコマンドをISO8601/RFC2822/RFC3339形式で出力する

ISO8601

man date より抜粋

-I[TIMESPEC], --iso-8601[=TIMESPEC]
output date/time in ISO 8601 format. TIMESPEC='date' for date only (the default), 'hours', 'minutes', 'seconds', or 'ns' for date and time to
the indicated precision.

Sample Script

Gist上に同一スクリプト有。

iso_date.sh

#!/bin/bash


function date_wrapper() {
    command="date --iso-8601=$1"
    echo "$ ${command}"
    echo -e "`${command}`\n"
}


echo -e "date command output with ISO8601 format.\n"

command="date --iso-8601"
echo "$ ${command}"
echo -e "`${command}`\n"


for format in date hours minutes seconds ns
do
    date_wrapper ${format}
done

execution-example

> ./iso_date.sh
date command output with ISO8601 format.

$ date --iso-8601
2017-01-22

$ date --iso-8601=date
2017-01-22

$ date --iso-8601=hours
2017-01-22T14+0900

$ date --iso-8601=minutes
2017-01-22T14:01+0900

$ date --iso-8601=seconds
2017-01-22T14:01:16+0900

$ date --iso-8601=ns
2017-01-22T14:01:16,631109694+0900

RFC2822/RFC3339

man date より抜粋

-R, --rfc-2822
output date and time in RFC 2822 format. Example: Mon, 07 Aug 2006 12:34:56 -0600

--rfc-3339=TIMESPEC
output date and time in RFC 3339 format. TIMESPEC='date', 'seconds', or 'ns' for date and time to the indicated precision. Date and time com-
ponents are separated by a single space: 2006-08-07 12:34:56-06:00

Sample Script

Gist上に同一スクリプト有。

bash.sh

#!/bin/bash


function date_wrapper() {
    command="date --rfc-3339=$1"
    echo "$ ${command}"
    echo -e "`${command}`\n"
}


echo -e "--- date command output with RFC 2822 format ---"
command="date --rfc-2822"
echo "$ ${command}"
echo -e "`${command}`\n"


echo -e "--- date command output with RFC 3399 format ---"
for format in date seconds ns
do
    date_wrapper ${format}
done

execution-example

--- date command output with RFC 2822 format ---
$ date --rfc-2822
Sun, 22 Jan 2017 14:12:25 +0900

--- date command output with RFC 3399 format ---
$ date --rfc-3339=date
2017-01-22

$ date --rfc-3339=seconds
2017-01-22 14:12:25+09:00

$ date --rfc-3339=ns
2017-01-22 14:12:25.698220571+09:00