title: Locally caching specific artifacts in Nexus
body: <p>I am currently evaluating Nexus to see if it can meet the requirements for our company. I can't seem to find what I need in the manual, so I thought I would ask before giving up on it.</p>
  
  <p>We have a strict requirement that only specifically authorized OSS libraries (and their dependencies) can be used for development. We would like to achieve this without giving up automatic resolution of transitive dependencies, so Nexus seemed like a good tool for this. </p>
  
  <p>The idea is that we could keep all of our proxied repositories in "Blocked" mode, thus allowing Nexus to serve locally cached artifacts, but refusing to go out to the Internet if a build asks for something that is not already cached.</p>
  
  <p>The "OSS Manager" (person) would then log in with his admin id, take the repositories out of "Blocked" mode, and then somehow tell Nexus to download the list of libraries that he wants to authorize. After all the libraries and their dependencies have been locally cached, he would place the repositories back into "Blocked" mode.</p>
  
  <p>I can't seem to find a way to tell Nexus to download a library and it dependencies from the UI. The "OSS Manager" is not a developer, so setting up a custom Maven or Gradle build every time they want to add authorized libraries is not an option.</p>
  
  <p>Can I achieve this with bare Nexus (or maybe a plugin?), or do I need to write a custom app that the "OSS Manager" will use to generate a fake Maven build based on the list of desired libraries, and then run that build against the Nexus instance while it is in "Unblocked" state?</p>