Client

Everything starts with a NexusRest. Create one per Nexus and reuse it. It holds the HTTP client, the rate limit and the threads for asynchronous requests.

Create a client

NexusRest nexus = NexusRest.defaultApi("eldonexus.de");

defaultApi(host) is short for NexusRest.builder(host).build(). Use the builder when you want to change anything:

NexusRest nexus = NexusRest.builder("nexus.example.com")
        .setPasswordAuth("deployer", System.getenv("NEXUS_PASSWORD"))
        .build();

With a host name, like nexus.example.com or nexus.example.com:8443, the client talks to https://<host>/service/rest.

For a Nexus on plain HTTP or below a path, pass its base URL instead. The client adds /service/rest itself:

NexusRest nexus = NexusRest.builder(URI.create("http://localhost:8081")).build();
NexusRest behindProxy = NexusRest.builder(URI.create("https://example.com/nexus")).build();

Log in

Anonymous access is enough for public repositories. For anything else, log in with one of these:

Method	What it does
setPasswordAuth(username, password)	Sends an HTTP Basic Authorization header with every request. Works for users and for user tokens.
setAuth(Authenticator)	Sets a java.net.Authenticator on the HTTP client. Java only sends credentials after the server asked for them.
header(key, value)	Adds any header to every request, for example a token header of a proxy in front of your Nexus.

The headers go to every URL the client calls, also to the downloadUrl of an asset. Nexus returns download URLs on its own host, so this is the same server.

Use your own HTTP client

By default the builder creates a java.net.http.HttpClient that prefers HTTP/2, follows redirects (but not from HTTPS to HTTP) and waits up to 60 seconds for a connection. Pass your own client to change that:

HttpClient http = HttpClient.newBuilder()
        .connectTimeout(Duration.ofSeconds(10))
        .build();

NexusRest nexus = NexusRest.builder("nexus.example.com")
        .setHttp(http)
        .build();

note

With setHttp(...) the builder uses your client as it is. An Authenticator set with setAuth(...) is ignored then; set it on your own client instead. Headers from setPasswordAuth(...) and header(...) still work.

Threads for asynchronous requests

queue() runs requests on a ScheduledExecutorService. By default the builder creates a pool with two threads. Pass your own to control the threads:

ScheduledExecutorService executor = Executors.newScheduledThreadPool(4);

NexusRest nexus = NexusRest.builder("nexus.example.com")
        .setExecutorService(executor)
        .build();

The default pool uses daemon threads named nexus-api-wrapper-<n>, so it never keeps your program running. The client has no close(); an executor you pass in is yours to shut down.

Logging

The client logs every request URI and every JSON response body at TRACE level through SLF4J, under the logger de.chojo.nexus.NexusRestImpl.