/ 
ETL-Yertl-0.044
River stage zero No dependents
/ yts

NAME

yts - Read/write time series data

VERSION

version 0.044

SYNOPSIS

# Read a time series
yts [-s] <db_spec> <metric> [--start <datetime>] [--end <datetime>] \
    [--tag <name>=<value>]

# Write a time series
yts [-s] <db_spec> [<metric>] [--tag <name>=<value>]

yts -h|--help|--version

DESCRIPTION

This program reads and writes time series data. Time series are lists of date/time and value pairs, optionally with additional metadata tags attached to them. Time series are stored in databases as metrics.

Since time series databases have a vast array of features, some of these arguments/options will not make sense for your database. Any database that does not support a feature you've requested will cause yts to exit with an error message.

Reading Time Series

To read a time series, ask for a metric. This will display a set of YAML documents describing the values in the series.

$ yts influx://localhost:8086 mydb.cpu_load_1m
---
timestamp: 2017-01-01T00:00:00
metric: mydb.cpu_load_1m
value: 1.23
tags:
    server: 10.0.0.1
---
timestamp: 2017-01-01T00:00:00
metric: mydb.cpu_load_1m
value: 0.61
tags:
    server: 10.0.0.2

To show only the timestamp and value of a single metric, use the --short format:

$ yts -s influx://localhost:8086 mydb.cpu_load_1m
---
'2017-01-01T00:00:00': 1.23
'2017-01-01T00:00:10': 1.26
'2017-01-01T00:00:20': 1.13

If multiple series are being shown with duplicate timestamps, some values will be missing.

Writing Time Series

If yts has input to read, it will write new values to the time series database. These values are YAML documents in one of the following formats:

Long format

This format is a series of YAML documents that describe each point fully. Use this format if you want to write to many different metrics with different tags for each metric. The timestamp can be any ISO8601 date/time format or an epoch timestamp. The value can be anything the time series database accepts.

---
timestamp: 2017-01-01T00:00:00
metric: mydb.cpu_load_1m.value
value: 1.23
tags:
    server: 10.0.0.1
---
timestamp: 2017-01-01T00:00:10
metric: mydb.cpu_load_1m.value
value: 1.26
tags:
    server: 10.0.0.1

If your documents have tags, but the database does not support per-value tagging, yts will exit with an error message.

Short format

If you pass in the --short option, you can use the short format. This format is a set of date/value pairs. The date can be any ISO8601 date/time format or an epoch timestamp. The value can be anything the time series database accepts.

---
'2017-01-01T00:00:00': 1.23
'2017-01-01T00:00:10': 1.26
'2017-01-01T00:00:20': 1.13

This format can only usefully handle one metric. The metric to write is taken from the command line. Any tags specified on the command line will be attached to every point as it is written.

ARGUMENTS

db_spec

The database to connect to, in the format <adapter>://<host>:<port>.

These adapters come with Yertl:

metric

The metric to read/write. Databases may specify metrics in different ways. See the adapter documentation for more information.

OPTIONS

--start <datetime>

When reading, only get points starting at or after the given date/time. Date/time are accepted in any ISO8601 format (YYYY-MM-DD, YYYY-MM-DDTHH:MM:SS) or as a UNIX epoch timestamp.

--end <datetime>

When reading, only get points ending at or before the given date/time. Date/time are accepted in any ISO8601 format (YYYY-MM-DD, YYYY-MM-DDTHH:MM:SS) or as a UNIX epoch timestamp.

--tag <name>=<value>

When reading, only read values with the given tag name equal to the given value. When writing, write the given tag name and value to every point, unless the point specifies a different value for the tag.

If the time series database does not support tagging of individual values, this option will cause yts to exit with an error.

-s | --short

Read/write the time series in the "short" format. See "Short Format" for more information.

-h | --help

Show this help document.

--version

Print the current ysql and Perl versions.

ENVIRONMENT VARIABLES

YERTL_FORMAT

Specify the default format Yertl uses between commands. Defaults to yaml. Can be set to json for interoperability with other programs.

AUTHOR

Doug Bell <preaction@cpan.org>

COPYRIGHT AND LICENSE

This software is copyright (c) 2018 by Doug Bell.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.