Catch exceptions in filter (#267)

adding try catch for filter jars implementations

Author: shashank11p

filter-api/src/main/java/org/hypertrace/agent/filter/FilterRegistry.java

@@ -54,7 +54,11 @@ public static Filter getFilter() {
     if (filter == null) {
       synchronized (FilterRegistry.class) {
         if (filter == null) {
-          filter = load();
+          try {
+            filter = load();
+          } catch (Throwable t) {
+            logger.error("Throwable thrown while loading filter jars", t);
+          }
         }
       }
     }

filter-api/src/main/java/org/hypertrace/agent/filter/MultiFilter.java

@@ -20,9 +20,13 @@
 import java.util.List;
 import java.util.Map;
 import org.hypertrace.agent.filter.api.Filter;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 class MultiFilter implements Filter {
 
+  private static final Logger logger = LoggerFactory.getLogger(MultiFilter.class);
+
   private final List<Filter> filters;
 
   public MultiFilter(List<Filter> filters) {
@@ -33,8 +37,15 @@ public MultiFilter(List<Filter> filters) {
   public boolean evaluateRequestHeaders(Span span, Map<String, String> headers) {
     boolean shouldBlock = false;
     for (Filter filter : filters) {
-      if (filter.evaluateRequestHeaders(span, headers)) {
-        shouldBlock = true;
+      try {
+        if (filter.evaluateRequestHeaders(span, headers)) {
+          shouldBlock = true;
+        }
+      } catch (Throwable t) {
+        logger.warn(
+            "Throwable thrown while evaluating Request headers for filter {}",
+            filter.getClass().getName(),
+            t);
       }
     }
     return shouldBlock;
@@ -44,8 +55,15 @@ public boolean evaluateRequestHeaders(Span span, Map<String, String> headers) {
   public boolean evaluateRequestBody(Span span, String body) {
     boolean shouldBlock = false;
     for (Filter filter : filters) {
-      if (filter.evaluateRequestBody(span, body)) {
-        shouldBlock = true;
+      try {
+        if (filter.evaluateRequestBody(span, body)) {
+          shouldBlock = true;
+        }
+      } catch (Throwable t) {
+        logger.warn(
+            "Throwable thrown while evaluating Request body for filter {}",
+            filter.getClass().getName(),
+            t);
       }
     }
     return shouldBlock;