Surface websphere cell and server name on process tags (#8880)

Author: amarziali

internal-api/src/main/java/datadog/trace/api/ProcessTags.java

@@ -10,6 +10,7 @@
 import java.util.Map;
 import java.util.SortedMap;
 import java.util.TreeMap;
+import java.util.function.Function;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
 import org.slf4j.Logger;
@@ -18,6 +19,14 @@
 public class ProcessTags {
   private static final Logger LOGGER = LoggerFactory.getLogger(ProcessTags.class);
   private static boolean enabled = Config.get().isExperimentalPropagateProcessTagsEnabled();
+  public static final String CLUSTER_NAME = "cluster.name";
+  public static final String SERVER_NAME = "server.name";
+  public static final String ENTRYPOINT_NAME = "entrypoint.name";
+  public static final String ENTRYPOINT_BASEDIR = "entrypoint.basedir";
+  public static final String ENTRYPOINT_WORKDIR = "entrypoint.workdir";
+
+  // visible for testing
+  static Function<String, String> envGetter = System::getenv;
 
   private static class Lazy {
     // the tags are used to compute a hash for dsm hence that map must be sorted.
@@ -31,22 +40,50 @@ private static SortedMap<String, String> loadTags() {
       if (enabled) {
         try {
           fillBaseTags(tags);
-          fillJbossTags(tags);
+          fillJeeTags(tags);
         } catch (Throwable t) {
           LOGGER.debug("Unable to calculate default process tags", t);
         }
       }
       return tags;
     }
 
-    private static void insertSysPropIfPresent(
+    private static void fillJeeTags(SortedMap<String, String> tags) {
+      if (fillJbossTags(tags)) {
+        return;
+      }
+      fillWebsphereTags(tags);
+    }
+
+    private static void insertTagFromSysPropIfPresent(
         Map<String, String> tags, String propKey, String tagKey) {
-      String value = System.getProperty(propKey);
+      String value = maybeGetSystemProperty(propKey);
       if (value != null) {
         tags.put(tagKey, value);
       }
     }
 
+    private static String maybeGetSystemProperty(String propKey) {
+      try {
+        return System.getProperty(propKey);
+      } catch (Throwable ignored) {
+      }
+      return null;
+    }
+
+    private static boolean insertTagFromEnvIfPresent(
+        Map<String, String> tags, String envKey, String tagKey) {
+      try {
+        String value = envGetter.apply(envKey);
+        if (value != null) {
+          tags.put(tagKey, value);
+          return true;
+        }
+      } catch (Throwable ignored) {
+      }
+      return false;
+    }
+
     private static boolean insertLastPathSegmentIfPresent(
         Map<String, String> tags, String path, String tagKey) {
       if (path == null || path.isEmpty()) {
@@ -63,31 +100,47 @@ private static boolean insertLastPathSegmentIfPresent(
       return false;
     }
 
+    private static boolean hasSystemProperty(String propKey) {
+      try {
+        return System.getProperties().containsKey(propKey);
+      } catch (Throwable ignored) {
+      }
+      return false;
+    }
+
     private static void fillBaseTags(Map<String, String> tags) {
       final CapturedEnvironment.ProcessInfo processInfo =
           CapturedEnvironment.get().getProcessInfo();
       if (processInfo.mainClass != null) {
-        tags.put("entrypoint.name", processInfo.mainClass);
+        tags.put(ENTRYPOINT_NAME, processInfo.mainClass);
         tags.put("entrypoint.type", "class");
       }
       if (processInfo.jarFile != null) {
         final String jarName = processInfo.jarFile.getName();
-        tags.put("entrypoint.name", jarName.substring(0, jarName.length() - 4)); // strip .jar
+        tags.put(ENTRYPOINT_NAME, jarName.substring(0, jarName.length() - 4)); // strip .jar
         tags.put("entrypoint.type", "jar");
-        insertLastPathSegmentIfPresent(tags, processInfo.jarFile.getParent(), "entrypoint.basedir");
+        insertLastPathSegmentIfPresent(tags, processInfo.jarFile.getParent(), ENTRYPOINT_BASEDIR);
       }
 
-      insertLastPathSegmentIfPresent(tags, System.getProperty("user.dir"), "entrypoint.workdir");
+      insertLastPathSegmentIfPresent(tags, maybeGetSystemProperty("user.dir"), ENTRYPOINT_WORKDIR);
     }
 
-    private static void fillJbossTags(Map<String, String> tags) {
+    private static boolean fillJbossTags(Map<String, String> tags) {
       if (insertLastPathSegmentIfPresent(
-          tags, System.getProperty("jboss.home.dir"), "jboss.home")) {
-        insertSysPropIfPresent(tags, "jboss.server.name", "server.name");
-        tags.put(
-            "jboss.mode",
-            System.getProperties().containsKey("[Standalone]") ? "standalone" : "domain");
+          tags, maybeGetSystemProperty("jboss.home.dir"), "jboss.home")) {
+        insertTagFromSysPropIfPresent(tags, "jboss.server.name", SERVER_NAME);
+        tags.put("jboss.mode", hasSystemProperty("[Standalone]") ? "standalone" : "domain");
+        return true;
       }
+      return false;
+    }
+
+    private static boolean fillWebsphereTags(Map<String, String> tags) {
+      if (insertTagFromEnvIfPresent(tags, "WAS_CELL", CLUSTER_NAME)) {
+        insertTagFromEnvIfPresent(tags, "SERVER_NAME", SERVER_NAME);
+        return true;
+      }
+      return false;
     }
 
     static void calculate() {

internal-api/src/test/groovy/datadog/trace/api/ProcessTagsForkedTest.groovy

@@ -61,6 +61,33 @@ class ProcessTagsForkedTest extends DDSpecification {
     null                  | "[Standalone]"    | "standalone" | "entrypoint.basedir:somewhere,entrypoint.name:jboss-modules,entrypoint.type:jar,entrypoint.workdir:[^,]+" // don't expect jboss tags since home is missing
   }
 
+  def 'should load websphere tags (#expected)'() {
+    setup:
+    injectSysConfig(EXPERIMENTAL_PROPAGATE_PROCESS_TAGS_ENABLED, "true")
+    ProcessTags.envGetter = key -> {
+      switch (key) {
+        case "WAS_CELL":
+        return cellName
+        case "SERVER_NAME":
+        return serverName
+        default:
+        return null
+      }
+    }
+    ProcessTags.reset()
+    when:
+    def tags = ProcessTags.getTagsForSerialization()
+    then:
+    assert tags =~ expected
+    cleanup:
+    ProcessTags.envGetter = System::getenv
+    ProcessTags.reset()
+    where:
+    cellName | serverName | expected
+    "cell1"  | "server1"  | "cluster.name:cell1,.+,server.name:server1.*"
+    null     | "server1"  | "^((?!cluster.name|server.name).)*\$"
+  }
+
   def 'should not calculate process tags by default'() {
     when:
     ProcessTags.reset()