Given the Maven coordinates (group, artifact, version) of an arbitrary released artifact that you're capable of resolving, (an artifact which may or may not have been sent to Maven Central - could have been released to another artifact repository, public or private), what is the best way to determine the release date of that artifact?
Use case
Scala Steward is a bot that helps keep project library dependencies up to date, automatically opening PRs to update dependencies. However, some dependencies - like AWS Java SDK - are updated too frequently, leading to excessive numbers of PRs. In order for Scala Steward to deal with that, it would be helpful for Scala Steward to know the release dates of the artifacts it's considering updating.
...some available sources of data
- search.maven.org exposes a REST API that has a
timestampfield for each artifact (see eg https://search.maven.org/solrsearch/select?q=g:software.amazon.awssdk%20AND%20a:s3%20AND%20v:2.17.71&rows=20&wt=json), which is great, but unfortunately only useful for artifacts that have been published to Maven Central. - There's a
<lastUpdated>field in themaven-metadata.xmlfile that's published with each artifact (see, eg https://repo1.maven.org/maven2/software/amazon/awssdk/s3/maven-metadata.xml), but that's not specific to an artifact version - it just relates to the latest published version of that artifact, no good if you want to know about an older one. Here's the code that creates that file. - Coursier API has a Versions#lastUpdated field which I presume is just the data from the
<lastUpdated>field in themaven-metadata.xmlfile? - The raw directory listing of an artifact version folder - assuming you can access it - will often give a timestamp against each file- however, this has no standard format, and it's position and datetime format will vary depending on how the webserver is set up:
- https://repo1.maven.org/maven2/software/amazon/awssdk/s3/2.17.71/ gives a raw text grid, with
2021-10-29 20:53in the 2nd column - https://repo.clojars.org/Hermes/Hermes/0.1.0-SNAPSHOT/ gives
2020-02-09T14:36:26.000Zin the 1st column
- https://repo1.maven.org/maven2/software/amazon/awssdk/s3/2.17.71/ gives a raw text grid, with
Some resources:
- https://www.deps.co/guides/public-maven-repositories/
- https://cwiki.apache.org/confluence/display/MAVENOLD/Repository+Layout+-+Final ...a document from 2005 describing the final design of Maven 2's repository layout. Also:
See also Retrieving artifact release date using Aether Eclipse, which asked this question specific to just the Aether Eclipse library (now known as Maven Artifact Resolver), whereas I'm interested to know if there is anything that works reliably for obtaining this information.