A JVM port of Forgetsy in Kotlin. Data is stored in Redis, so you'll need one of those.
...
jedisPool = JedisPool(redisHost, redisPort)
val followsData = Delta(jedisPool, name, 7.days(), true)
followsData.increment("UserFoo", date = 14.daysAgo())
followsData.increment("UserBar", date = 10.daysAgo())
followsData.increment("UserBar", date = 7.daysAgo())
followsData.increment("UserFoo", date = 1.daysAgo())
followsData.increment("UserFoo")
println(followsData.fetch())Outputs:
{UserFoo=0.6666666666666666, UserBar=0.5}
forgetsy-jvm is distributed included in jcenter. If you're using Gradle, add
jcenter() to your repositories block:
repositories {
jcenter()
}
If you use Maven, rethink your life choices (Maven is fine to keep using, but for new projects it's worth learning Gradle):
<repositories>
<repository>
<id>jcenter</id>
<url>https://jcenter.bintray.com/</url>
</repository>
</repositories>
Then just add the dependency.
In Gradle:
compile 'net.dinomite:forgetsy:0.3.3'
In Maven (ick):
<dependency>
<groupId>net.dinomite</groupId>
<artifactId>forgetsy</artifactId>
<version>0.3.3</version>
<type>pom</type>
</dependency>
Delta will
attempt to use existing data in Redis if you don't provide a lifetime for and the underlying Sorted Sets exist,
throwing IllegalStateException if the data isn't found. If you want to re-use existing data upon restart of your app,
but create a new one if necessary, do something like this:
var delta = reifyOrMakeDelta(jedisPool)
fun reifyOrMakeDelta(jedisPool: JedisPool): Delta {
try {
return Delta(jedisPool, "namesy")
} catch (e: IllegalStateException) {
return Delta(jedisPool, "namesy", Duration.ofDays(10))
}
}The most common interaction with your delta will be incrementing bins:
delta.increment("$binName")Use the fetch() method to get the stats about what is trending:
delta.fetch()Deltas are likely to contain more bins than you want to see. Pass a count to fetch to get the top n buckets:
delta.fetch(25)This library is written in Kotlin and I use it from Kotlin. Kotlin has great Java interop…but this library makes use of named arguments which Java doesn't support and likely makes the API as viewed from Java pretty janky. If you want to use this from Java provide a PR or just let me know and we can work on it together.