Added try-catch to validate the regex passed to matches in SpanFilterMatcher (#166)

* Added try-catch to validate the regex passed

* Addressed review comments

* Unwanted change

* Addressed review comments

Author: sanket-mundra

span-processing-utils/src/main/java/org/hypertrace/config/span/processing/utils/SpanFilterMatcher.java

@@ -111,7 +111,18 @@ private boolean matches(String lhs, String rhs, RelationalOperator relationalOpe
       case RELATIONAL_OPERATOR_ENDS_WITH:
         return lhs.endsWith(rhs);
       case RELATIONAL_OPERATOR_REGEX_MATCH:
-        return Pattern.compile(rhs).matcher(lhs).find();
+        try {
+          return Pattern.compile(rhs).matcher(lhs).find();
+        } catch (Exception e) {
+          log.error("Invalid regex: {} passed to match: {}", rhs, e);
+          if (log.isDebugEnabled()) {
+            log.debug(
+                "Invalid regex passed to match. Hence returning false. lhs: {} and rhs: {}",
+                lhs,
+                rhs);
+          }
+          return false;
+        }
       default:
         log.error("Unsupported relational operator for string value rhs:{}", relationalOperator);
         return false;

span-processing-utils/src/test/java/org/hypertrace/config/span/processing/utils/SpanFilterMatcherTest.java

@@ -93,6 +93,11 @@ void testMatcher() {
             "name",
             buildSpanFilterValue("[a-zA-z]+[0-9]+"),
             RelationalOperator.RELATIONAL_OPERATOR_REGEX_MATCH));
+    assertFalse(
+        this.spanFilterMatcher.matches(
+            "name",
+            buildSpanFilterValue("[(name"),
+            RelationalOperator.RELATIONAL_OPERATOR_REGEX_MATCH));
 
     assertTrue(
         this.spanFilterMatcher.matches(