palicao/php-redis-time-series

Use Redis Time Series in PHP

2.1.1 2020-10-27 21:07 UTC

Requires

• php: >=7.2.0
• ext-redis: *

Requires (Dev)

• phpunit/phpunit: ^8.3
• vimeo/psalm: ^3.5

MIT

• Alessandro Balasco

README

Use Redis Time Series in PHP!

Getting up and running

Install

composer require palicao/php-redis-time-series

Requirements

The library is tested against:

• PHP 7.2, 7.3, 7.4, 8.0
• RedisTimeSeries 1.4.10 (but it should work with any 1.4 version)

In order to use RedisTimeSeries 1.2 please use version 2.1.1 of this library.

Construct

$ts = new TimeSeries(
    new RedisClient(
        new Redis(),
        new RedisConnectionParams($host, $port)
    )
);

TimeSeries methods

create

TimeSeries::create(string $key, ?int $retentionMs = null, array $labels = []): void

Creates a key, optionally setting a retention time (in milliseconds) and some labels.

See https://oss.redislabs.com/redistimeseries/commands/#tscreate.

alter

TimeSeries::alter(string $key, ?int $retentionMs = null, array $labels = []): void

Modifies an existing key's retention time and/or labels.

See https://oss.redislabs.com/redistimeseries/commands/#tsalter.

add

TimeSeries::add(Sample $sample, ?int $retentionMs = null, array $labels = []): Sample

Adds a sample.

If the key was not explicitly created, it's possible to set retention and labels.

See https://oss.redislabs.com/redistimeseries/commands/#tsadd.

Examples:

• $sample = $ts->add(new Sample('myKey', 32.10), 10, [new Label('myLabel', 'myValue')]); Adds a sample to myKey at the current timestamp (time of the redis server) and returns it (complete with dateTime).
• $sample = $ts->add(new Sample('myKey', 32.10, new DateTimeImmutable()), 10, [new Label('myLabel', 'myValue')]); Adds a sample to myKey at a given datetime and returns it.

Please notice that RedisTimeSeries only allows to add samples in order (no sample older than the latest is allowed)

addMany

TimeSeries::addMany(array $samples): array

Adds several samples.

As usual, if no timestamp is provided, the redis server current time is used. Added samples are returned in an array.

See https://oss.redislabs.com/redistimeseries/commands/#tsmadd.

incrementBy and decrementBy

TimeSeries::incrementBy(Sample $sample, ?int $resetMs = null, ?int $retentionMs = null, array $labels = []): void

TimeSeries::decrementBy(Sample $sample, ?int $resetMs = null, ?int $retentionMs = null, array $labels = []): void

Add a sample to a key, incrementing or decrementing the last value by an amount specified in $sample. The value can be optionally reset after $resetMs milliseconds.

Similarly to add, if the command is used on a non-existing key, it's possible to set retention and labels.

See https://oss.redislabs.com/redistimeseries/commands/#tsincrbytsdecrby.

createRule

TimeSeries::createRule(string $sourceKey, string $destKey, AggregationRule $rule): void

Creates an aggregation rule which applies the given $rule to $sourceKey in order to populate $destKey.

Notice that both key must already exist otherwise the command will fail.

See https://oss.redislabs.com/redistimeseries/commands/#tscreaterule.

Example:

• $ts->createRule('source', 'destination', new AggregationRule(AggregationRule::AVG, 10000), will populate the destination key by averaging the samples contained in source over 10 second buckets.

deleteRule

TimeSeries::deleteRule(string $sourceKey, string $destKey): void

Deletes an existing aggregation rule.

See https://oss.redislabs.com/redistimeseries/commands/#tsdeleterule.

range

TimeSeries::range(string $key, ?DateTimeInterface $from = null, ?DateTimeInterface $to = null, ?int $count = null, ?AggregationRule $rule = null, bool $reverse = false): Sample[]

Retrieves samples from a key. It's possible to limit the query in a given time frame (passing $from and $to), to limit the retrieved amount of samples (passing $count), and also to pre-aggregate the results using a $rule.

The flag $reverse will return the results in reverse time order.

See https://oss.redislabs.com/redistimeseries/commands/#tsrange.

multiRange and multiRangeWithLabels

TimeSeries::multiRange(Filter $filter, ?DateTimeInterface $from = null, ?DateTimeInterface $to = null, ?int $count = null, ?AggregationRule $rule = null, bool $reverse = false): Sample[]

TimeSeries::multiRangeWithLabels(Filter $filter, ?DateTimeInterface $from = null, ?DateTimeInterface $to = null, ?int $count = null, ?AggregationRule $rule = null, bool $reverse = false): SampleWithLabels[]

Similar to range, but instead of querying by key, queries for a specific set of labels specified in $filter.

multiRangeWithLabels will return an array of SampleWithLabels instead of simple Samples.

The flag $reverse will return the results in reverse time order.

See https://oss.redislabs.com/redistimeseries/commands/#tsmrange.

getLastSample

TimeSeries::getLastSample(string $key): Sample

Gets the last sample for a key.

See https://oss.redislabs.com/redistimeseries/commands/#tsget.

getLastSamples

TimeSeries::getLastSamples(Filter $filter): Sample[]

Gets the last sample for a set of keys matching a given $filter.

See https://oss.redislabs.com/redistimeseries/commands/#tsmget.

info

TimeSeries::info(string $key): Metadata

Gets useful metadata for a given key.

See https://oss.redislabs.com/redistimeseries/commands/#tsinfo.

getKeysByFilter

getKeysByFilter(Filter $filter): string[]

Retrieves the list of keys matching a given $filter.

See https://oss.redislabs.com/redistimeseries/commands/#tsqueryindex.

Advanced connection parameters

You can manipulate your RedisConnectionParams using the following methods:

• RedisConnectionParams::setPersistentConnection(bool $persistentConnection) enable/disable a persistent connection
• RedisConnectionParams::setTimeout(int $timeout) connection timeout in seconds
• RedisConnectionParams::setRetryInterval(int $retryInterval) retry interval in seconds
• RedisConnectionParams::setReadTimeout(float $readTimeout) read timeout in seconds

Building Filters

A Filter is composed of multiple filtering operations. At least one equality operation must be provided (in the constructor). Adding filtering operations can be chained using the method add.

Examples:

• $f = (new Filter('label1', 'value1'))->add('label2', Filter::OP_EXISTS); filters items which have label1 = value1 and have label2.
• $f = (new Filter('label1', 'value1'))->add('label2', Filter::OP_IN, ['a', 'b', 'c']); filters items which have label1 = value1 and where label2 is one of 'a', 'b' or 'c'.

Local testing

For local testing you can use the provided docker-compose.yml file, which will create a PHP container (with the redis extension pre-installed), and a redis container (with Redis Time Series included).

Contributors

Thanks Mrkisha for the precious contributions.