Fix label filter for proper prefix/suffix regex

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/optimizer/rules/logical/promql/AutomatonUtils.java

@@ -133,10 +133,12 @@ private static String removeEndingAnchor(String normalized) {
      */
     public static class PatternFragment {
         public enum Type {
-            EXACT,      // Exact literal match
-            PREFIX,     // Starts with literal
-            SUFFIX,     // Ends with literal
-            REGEX       // Complex regex pattern
+            EXACT,         // Exact literal match
+            PREFIX,        // Starts with literal
+            PROPER_PREFIX, // Starts with literal but not the literal itself
+            SUFFIX,        // Ends with literal
+            PROPER_SUFFIX, // Ends with literal but not the literal itself
+            REGEX          // Complex regex pattern
         }
 
         private final Type type;
@@ -183,7 +185,10 @@ private static PatternFragment classifyPart(String part) {
             // Suffix pattern: .*suffix
             String suffix = trimmed.substring(2);
             if (isLiteral(suffix)) {
-                return new PatternFragment(PatternFragment.Type.SUFFIX, suffix);
+                return new PatternFragment(
+                    trimmed.startsWith(".*") ? PatternFragment.Type.SUFFIX : PatternFragment.Type.PROPER_SUFFIX,
+                    suffix
+                );
             }
             // Complex suffix pattern - fallback to REGEX
             return new PatternFragment(PatternFragment.Type.REGEX, part.trim());
@@ -193,7 +198,10 @@ private static PatternFragment classifyPart(String part) {
             // Prefix pattern: prefix.*
             String prefix = trimmed.substring(0, trimmed.length() - 2);
             if (isLiteral(prefix)) {
-                return new PatternFragment(PatternFragment.Type.PREFIX, prefix);
+                return new PatternFragment(
+                    trimmed.endsWith(".*") ? PatternFragment.Type.PREFIX : PatternFragment.Type.PROPER_PREFIX,
+                    prefix
+                );
             }
             // Complex prefix pattern - fallback to REGEX
             return new PatternFragment(PatternFragment.Type.REGEX, part.trim());

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/optimizer/rules/logical/promql/TranslatePromqlToTimeSeriesAggregate.java

@@ -21,9 +21,11 @@
 import org.elasticsearch.xpack.esql.expression.function.scalar.string.StartsWith;
 import org.elasticsearch.xpack.esql.expression.function.scalar.string.regex.RLike;
 import org.elasticsearch.xpack.esql.expression.predicate.Predicates;
+import org.elasticsearch.xpack.esql.expression.predicate.logical.And;
 import org.elasticsearch.xpack.esql.expression.predicate.nulls.IsNotNull;
 import org.elasticsearch.xpack.esql.expression.predicate.operator.comparison.Equals;
 import org.elasticsearch.xpack.esql.expression.predicate.operator.comparison.In;
+import org.elasticsearch.xpack.esql.expression.predicate.operator.comparison.NotEquals;
 import org.elasticsearch.xpack.esql.expression.promql.function.PromqlFunctionRegistry;
 import org.elasticsearch.xpack.esql.optimizer.rules.logical.OptimizerRules;
 import org.elasticsearch.xpack.esql.optimizer.rules.logical.TranslateTimeSeriesAggregate;
@@ -339,7 +341,9 @@ private static Expression translatePatternFragment(Source source, Expression fie
         return switch (fragment.type()) {
             case EXACT -> new Equals(source, field, value);
             case PREFIX -> new StartsWith(source, field, value);
+            case PROPER_PREFIX -> new And(source, new NotEquals(source, field, value), new StartsWith(source, field, value));
             case SUFFIX -> new EndsWith(source, field, value);
+            case PROPER_SUFFIX -> new And(source, new NotEquals(source, field, value), new EndsWith(source, field, value));
             case REGEX -> new RLike(source, field, new RLikePattern(fragment.value()));
         };
     }

x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/optimizer/promql/PromqlLogicalPlanOptimizerTests.java

@@ -14,11 +14,16 @@
 import org.elasticsearch.xpack.esql.analysis.Analyzer;
 import org.elasticsearch.xpack.esql.analysis.AnalyzerContext;
 import org.elasticsearch.xpack.esql.core.tree.Source;
+import org.elasticsearch.xpack.esql.core.expression.predicate.regex.RegexMatch;
 import org.elasticsearch.xpack.esql.expression.function.EsqlFunctionRegistry;
+import org.elasticsearch.xpack.esql.expression.function.scalar.string.StartsWith;
+import org.elasticsearch.xpack.esql.expression.predicate.operator.comparison.In;
+import org.elasticsearch.xpack.esql.expression.predicate.operator.comparison.NotEquals;
 import org.elasticsearch.xpack.esql.index.EsIndex;
 import org.elasticsearch.xpack.esql.index.IndexResolution;
 import org.elasticsearch.xpack.esql.optimizer.AbstractLogicalPlanOptimizerTests;
 import org.elasticsearch.xpack.esql.plan.IndexPattern;
+import org.elasticsearch.xpack.esql.plan.logical.Filter;
 import org.elasticsearch.xpack.esql.plan.logical.LogicalPlan;
 import org.junit.BeforeClass;
 
@@ -28,6 +33,8 @@
 import static org.elasticsearch.xpack.esql.EsqlTestUtils.TEST_VERIFIER;
 import static org.elasticsearch.xpack.esql.EsqlTestUtils.emptyInferenceResolution;
 import static org.elasticsearch.xpack.esql.EsqlTestUtils.loadMapping;
+import static org.hamcrest.Matchers.equalTo;
+import static org.hamcrest.Matchers.hasSize;
 
 //@TestLogging(value="org.elasticsearch.xpack.esql:TRACE", reason="debug tests")
 //@Ignore("Proper assertions need to be added")
@@ -171,12 +178,15 @@ public void testLabelSelector() {
         String testQuery = """
             TS k8s
             | promql time now (
-                max by (pod)(avg_over_time(network.bytes_in{pod=~"host-0|host-1|host-2"}[5m]))
-                )
-
+                max by (pod) (avg_over_time(network.bytes_in{pod=~"host-0|host-1|host-2"}[5m]))
+              )
             """;
 
         var plan = planPromql(testQuery);
+        var filters = plan.collect(Filter.class::isInstance);
+        assertThat(filters, hasSize(1));
+        var filter = (Filter) filters.getFirst();
+        assertThat(filter.condition().anyMatch(In.class::isInstance), equalTo(true));
         System.out.println(plan);
     }
 
@@ -188,14 +198,48 @@ public void testLabelSelectorPrefix() {
         String testQuery = """
             TS k8s
             | promql time now (
-                avg by (pod)(avg_over_time(network.total_bytes_in{pod=~"host-.*"}[5m]))
+                avg by (pod) (avg_over_time(network.bytes_in{pod=~"host-.*"}[5m]))
                 )
             """;
 
         var plan = planPromql(testQuery);
+        var filters = plan.collect(Filter.class::isInstance);
+        assertThat(filters, hasSize(1));
+        var filter = (Filter) filters.getFirst();
+        assertThat(filter.condition().anyMatch(StartsWith.class::isInstance), equalTo(true));
+        assertThat(filter.condition().anyMatch(NotEquals.class::isInstance), equalTo(false));
         System.out.println(plan);
     }
 
+    public void testLabelSelectorProperPrefix() {
+        var plan = planPromql("""
+            TS k8s
+            | promql time now (
+                avg(avg_over_time(network.bytes_in{pod=~"host-.+"}[1h]))
+              )
+            """);
+
+        var filters = plan.collect(Filter.class::isInstance);
+        assertThat(filters, hasSize(1));
+        var filter = (Filter) filters.getFirst();
+        assertThat(filter.condition().anyMatch(StartsWith.class::isInstance), equalTo(true));
+        assertThat(filter.condition().anyMatch(NotEquals.class::isInstance), equalTo(true));
+    }
+
+    public void testLabelSelectorRegex() {
+        var plan = planPromql("""
+            TS k8s
+            | promql time now (
+                avg(avg_over_time(network.bytes_in{pod=~"[a-z]+"}[1h]))
+              )
+            """);
+
+        var filters = plan.collect(Filter.class::isInstance);
+        assertThat(filters, hasSize(1));
+        var filter = (Filter) filters.getFirst();
+        assertThat(filter.condition().anyMatch(RegexMatch.class::isInstance), equalTo(true));
+    }
+
     public void testFsUsageTop5() {
         // TS metrics-hostmetricsreceiver.otel-default | WHERE @timestamp >= \"{{from | minus .benchmark.duration}}\" AND @timestamp <=
         // \"{{from}}\"

x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/optimizer/rules/logical/promql/AutomatonUtilsTests.java

@@ -14,6 +14,8 @@
 
 import static org.elasticsearch.xpack.esql.optimizer.rules.logical.promql.AutomatonUtils.PatternFragment.Type.EXACT;
 import static org.elasticsearch.xpack.esql.optimizer.rules.logical.promql.AutomatonUtils.PatternFragment.Type.PREFIX;
+import static org.elasticsearch.xpack.esql.optimizer.rules.logical.promql.AutomatonUtils.PatternFragment.Type.PROPER_PREFIX;
+import static org.elasticsearch.xpack.esql.optimizer.rules.logical.promql.AutomatonUtils.PatternFragment.Type.PROPER_SUFFIX;
 import static org.elasticsearch.xpack.esql.optimizer.rules.logical.promql.AutomatonUtils.PatternFragment.Type.REGEX;
 import static org.elasticsearch.xpack.esql.optimizer.rules.logical.promql.AutomatonUtils.PatternFragment.Type.SUFFIX;
 import static org.elasticsearch.xpack.esql.optimizer.rules.logical.promql.AutomatonUtils.extractFragments;
@@ -63,6 +65,17 @@ public void testExtractFragments_MixedAlternation() {
         assertFragments(fragments, expected);
     }
 
+    public void testExtractFragments_ProperPrefixSuffixAlternation() {
+        List<PatternFragment> fragments = extractFragments("prod-.+|.+-dev");
+
+        assertThat(fragments, notNullValue());
+        assertThat(fragments, hasSize(2));
+
+        Object[][] expected = { { PROPER_PREFIX, "prod-" }, { PROPER_SUFFIX, "-dev" } };
+
+        assertFragments(fragments, expected);
+    }
+
     public void testExtractFragments_HomogeneousExactAlternation() {
         // All exact values
         List<PatternFragment> fragments = extractFragments("api|web|service");