Timestamp library and utility

tslib is a timestamp processing toolkit and library, written in Python. It is very helpful when dealing with the millisecond-precision timestamps that we encounter all the time in computer systems, and to work with human-readable time deltas away from "now".

Installation

You can install tslib directly from PyPI with the following command:

$ pip install tslib

If you're installing from a clone of this repository, use:

$ git clone https://github.com/mpetazzoni/tslib
$ cd tslib/
$ pip install -e .

tslib depends on pytz and six, which will be installed automatically.

You're now ready to use ts, which should be directly available in your $PATH.

Usage

$ ts -h
usage: ts [-h] [-t TZ] [-n] [-i]

Human readable timestamps

optional arguments:
  -h, --help            show this help message and exit
  -t TZ, --timezone TZ  Use TZ as the local timezone
  -n, --timestamp-only  Only output the resulting millisecond timestamp(s)
  -i, --inline          Apply timestamp replacements inline of the incoming
                        text

ts transforms milliseconds timestamps and human-readable deltas into fully qualified date and time printouts, containing:

• the UTC timestamp (since Epoch)
• the UTC time represented by the timestamp
• the local time represented by the timestamp
• the human-readable delta of this timestamp against current time

The output is tab-delimited and can easily be re-segmented by piping into column -t -s "\t".

Arguments can be passed as command-line arguments, or piped into ts via STDIN. If no input comes from either of these sources, ts will simply output the current time:

$ ts
1423599084206 2015-02-10 20:11:24.206 UTC+0000  2015-02-10 12:11:24.206 PST-0800  0

Inline mode

ts can operate in inline-replacement mode, for timestamps only. In this mode, you can pipe in any text and ts will output it back to you with all timestamps replaced with a human-readable date and time and human-readable delta representation.

Given the inherent difficulty of accurately matching timestamps, the matching is limited to 13-digits millisecond precision timestamps (that may be immediately followed by a L). Numbers smaller, or larger than 13 digits are not matched, and are left alone; meaning no 13-digit section of them is matched and replaced.

$ echo B_b-3PAAYAA B_cJXlvAYAA B_cJXl6AcAA \
    | xargs sfc mb g -p TSVH -f sf_checkpointTimestampMs -f sf_updatedOnMs \
    | ts -i \
    | column -t -s "    "
sf_id        sf_checkpointTimestampMs                              sf_updatedOnMs
B_b-3PAAYAA  2015-03-06 13:38:58.851 PST-0800 (-2w5h18m6s210)      2015-03-06 13:38:58.852 PST-0800 (-2w5h18m6s209)
B_cJXlvAYAA  2015-03-08 09:04:36.218 PDT-0700 (-1w5d10h52m28s843)  2015-03-08 09:04:36.218 PDT-0700 (-1w5d10h52m28s844)
B_cJXl6AcAA  2015-03-08 09:04:34.252 PDT-0700 (-1w5d10h52m30s810)  2015-03-08 09:04:34.342 PDT-0700 (-1w5d10h52m30s720)

More examples

Piping:

$ cat << EOF | ts
pipe heredoc> 1404424797009L
pipe heredoc> 1415917836779L
pipe heredoc> EOF
1404424797009 2014-07-03 21:59:57.009 UTC+0000  2014-07-03 14:59:57.009 PDT-0700  -31w5d1h14m26s38
1415917836779 2014-11-13 22:30:36.779 UTC+0000  2014-11-13 14:30:36.779 PST-0800  -12w5d43m46s268

Using the column output (assuming the same input in a /tmp/ts.txt file):

$ cat /tmp/ts.txt | ts | cut -f4
-31w5d1h16m17s703
-12w5d45m37s933

Sorting on a column (here, by descending timestamps in first column):

$ cat /tmp/ts.txt | ts | sort -k1 -t $'\t' -r
1415917836779 2014-11-13 22:30:36.779 UTC+0000  2014-11-13 14:30:36.779 PST-0800  -12w5d46m6s924
1404424797009 2014-07-03 21:59:57.009 UTC+0000  2014-07-03 14:59:57.009 PDT-0700  -31w5d1h16m46s694

Deltas

Human-readable deltas can be expressed in weeks (w), days (d), hours (h), minutes (m), and seconds (s). The remainder, without a unit, is assumed to be milliseconds. Any "segment" can be omitted, the only requirement is that the segments that are specified are written in descending order of span (days before hours, hours before minutes, etc.).

Here's an example: -12w4d6m57s257. Note that hours are missing, which simply means 12 weeks, 4 days, 6 minutes, 57 seconds and 257 milliseconds.

As you might have guessed, deltas can be both negative and positive. For positive deltas, the leading + may be omitted if units are used, otherwise the number is assumed to be an absolute timestamp:

$ ts -1
1423599850752 2015-02-10 20:24:10.752 UTC+0000  2015-02-10 12:24:10.752 PST-0800  -1
$ ts 0 1
            0 1970-01-01 00:00:00.000 UTC+0000  1969-12-31 16:00:00.000 PST-0800  -2353w5d20h24m14s145
            1 1970-01-01 00:00:00.001 UTC+0000  1969-12-31 16:00:00.001 PST-0800  -2353w5d20h24m14s144
$ ts +1
1423599855941 2015-02-10 20:24:15.941 UTC+0000  2015-02-10 12:24:15.941 PST-0800  1

Using a different local timezone

The third column shows the timestamp's representation in local time. It defaults to the US/Pacific timezone but this can be overridden with the -t command-line argument, passing in a timezone name that pytz understands:

$ ts -t Europe/Paris
1423600015955 2015-02-10 20:26:55.955 UTC+0000  2015-02-10 21:26:55.955 CET+0100  0

Absolute, human-readable offsets from Epoch

By prefixing a human-readable delta with an equal sign (=), you obtain an absolute offset from the Epoch. The side-effect of this is that it allows for converting a human-readable delta into its corresponding millisecond duration.

$ ts -n '=1h'
      3600000
$ ts '=1d'
     86400000 1970-01-02 00:00:00.000 UTC+0000  1970-01-01 16:00:00.000 PST-0800  -2365w6d21h56m20s98