Added a task to check for unpublished artifacts (#1453)

Staged Publishing via Sonatype Nexus fail occasionally. Sometime, the
staging process was complete, sometimes not. Since subsequence
publish-jobs fail for previously properly published artifacts, it's not
easy to tell, which CI publish jobs in failure state need a restart.

Therefore you can use theis new command to check for already published
modules.

Example: Some modules where published, some not

In that case, you need to find that shard, which published these
modules. In the CI log, go to the last lines, where all published
modules are printed. If you found the correct shard, restart it.

```
> mill checkPublishedArtifacts --artifacts __.publishSelfDependency --version 3.0.0-M1-3-47512ee8 --ttl "1 sec"
...
1 targets failed
checkPublishedArtifacts Missing 46 of 276 published artifacts: 
- com.lihaoyi:ammonite-compiler-interface_3.3.0:3.0.0-M1-3-47512ee8
- com.lihaoyi:ammonite-compiler-interface_3.3.1:3.0.0-M1-3-47512ee8
- com.lihaoyi:ammonite-compiler-interface_3.3.2:3.0.0-M1-3-47512ee8
- com.lihaoyi:ammonite-compiler-interface_3.3.3:3.0.0-M1-3-47512ee8
- com.lihaoyi:ammonite-compiler_3.2.2:3.0.0-M1-3-47512ee8
- com.lihaoyi:ammonite-compiler_3.3.0:3.0.0-M1-3-47512ee8
- com.lihaoyi:ammonite-compiler_3.3.1:3.0.0-M1-3-47512ee8
...
- com.lihaoyi:ammonite-sshd_3.3.2:3.0.0-M1-3-47512ee8
- com.lihaoyi:ammonite-sshd_3.3.3:3.0.0-M1-3-47512ee8
- com.lihaoyi:ammonite-terminal_3:3.0.0-M1-3-47512ee8
```

Example: All modules published successfully

```
> mill show checkPublishedArtifacts --artifacts __.publishSelfDependency --version 3.0.0-M1
[1/1] show 
[1/1] show > [2485/2485] checkPublishedArtifacts 
"All artifacts published for version 3.0.0-M1"
```

Example: All modules not published

```
> mill show checkPublishedArtifacts --artifacts __.publishSelfDependency --version 3.0.0-M2
[1/1] show 
[1/1] show > [2485/2485] checkPublishedArtifacts 
1 targets failed
show 1 targets failed
checkPublishedArtifacts All artifacts missing for version 3.0.0-M2
```

Pull request: #1453

build.sc

@@ -1,17 +1,22 @@
+// plugins
 import $ivy.`com.lihaoyi::mill-contrib-bloop:$MILL_VERSION`
 import $ivy.`io.get-coursier::coursier-launcher:2.1.0-RC1`
 import $file.ci.upload
-
+// imports
+import java.util.concurrent.atomic.AtomicInteger
+import scala.concurrent.{Await, ExecutionContext, Future, duration}
+import scala.util.chaining.scalaUtilChainingOps
+import coursier.mavenRepositoryString
 import mill._
-import scalalib._
-import publish._
+import mill.api.Result
 import mill.contrib.bloop.Bloop
-import mill.scalalib.api.ZincWorkerUtil._
-import coursier.mavenRepositoryString
 import mill.define.Command
+import mill.main.Tasks
+import mill.scalalib._
+import mill.scalalib.publish._
+import mill.scalalib.api.ZincWorkerUtil._
 import mill.testrunner.TestRunner
 
-import scala.util.chaining.scalaUtilChainingOps
 
 val ghOrg = "com-lihaoyi"
 val ghRepo = "Ammonite"
@@ -1018,3 +1023,34 @@ def publishSonatype(
         x: _*
       )
   }
+
+/**
+ * Somethime, the Mill publish command fails although the Sonatype publishing went through.
+ * This command checks, whether all artifacts are publshed.
+ * Run with:
+ * {{{
+ * mill checkPublishedArtifacts --artifacts __.publishSelfDependency --version {version} --ttl "1 sec"
+ * }}}
+  * See also https://github.com/com-lihaoyi/Ammonite/pull/1453
+ */
+def checkPublishedArtifacts(artifacts: Tasks[Artifact], version: String, ttl: String = "1 hour") = T.command {
+  val coords = T.sequence(artifacts.value)()
+  val next = new AtomicInteger(0)
+  val fut = coords.map { coord =>
+    Future {
+      val dep = s"${coord.group}:${coord.id}:${version}"
+      println(s"[${next.incrementAndGet()}/${coords.size}] Checking ${dep}")
+      val res = os.proc("cs", "complete-dep", dep, "-l", ttl)
+        .call().out.text().trim()
+      // println(res)
+      Option.when(!res.contains(version))(dep)
+    }(ExecutionContext.global)
+  }
+  val missing = fut.map(Await.result(_, duration.Duration.Inf)).flatten
+  val msg = if (missing.size == coords.size) s"All artifacts missing for version ${version}"
+  else s"Missing ${missing.size} of ${coords.size} published artifacts: ${
+      missing.mkString("\n- ", "\n- ", "")
+    }"
+  if(missing.isEmpty) Result.Success(s"All artifacts published for version ${version}")
+  else Result.Failure(msg)
+}