Validate flag content with a stricter regex

4 files changed, 32 insertions, 3 deletions

diff --git a/flags/src/main/java/com/yahoo/vespa/flags/Flags.java b/flags/src/main/java/com/yahoo/vespa/flags/Flags.java
index df307b581f1..c207fd63dbd 100644
--- a/flags/src/main/java/com/yahoo/vespa/flags/Flags.java
+++ b/flags/src/main/java/com/yahoo/vespa/flags/Flags.java
@@ -12,6 +12,7 @@ import java.time.format.DateTimeFormatter;
 import java.util.List;
 import java.util.Optional;
 import java.util.TreeMap;
+import java.util.function.Consumer;
 import java.util.function.Predicate;
 
 import static com.yahoo.vespa.flags.Dimension.APPLICATION;
@@ -528,6 +529,15 @@ public class Flags {
                 flagId, defaultValue, owners, createdAt, expiresAt, description, modificationEffect, dimensions);
     }
 
+    /** WARNING: public for testing: All flags should be defined in {@link Flags}. */
+    public static <T> UnboundListFlag<T> defineListFlag(String flagId, List<T> defaultValue, Class<T> elementClass,
+                                                        List<String> owners, String createdAt, String expiresAt,
+                                                        String description, String modificationEffect,
+                                                        Predicate<List<T>> validator, Dimension... dimensions) {
+        return define((fid, dval, fvec) -> new UnboundListFlag<>(fid, dval, elementClass, fvec, validator),
+                flagId, defaultValue, owners, createdAt, expiresAt, description, modificationEffect, dimensions);
+    }
+
     @FunctionalInterface
     private interface TypedUnboundFlagFactory<T, U extends UnboundFlag<?, ?, ?>> {
         U create(FlagId id, T defaultValue, FetchVector defaultFetchVector);
diff --git a/flags/src/main/java/com/yahoo/vespa/flags/JacksonArraySerializer.java b/flags/src/main/java/com/yahoo/vespa/flags/JacksonArraySerializer.java
index 8f7b7d71734..38e3b57d28b 100644
--- a/flags/src/main/java/com/yahoo/vespa/flags/JacksonArraySerializer.java
+++ b/flags/src/main/java/com/yahoo/vespa/flags/JacksonArraySerializer.java
@@ -4,20 +4,27 @@ package com.yahoo.vespa.flags;
 import com.fasterxml.jackson.databind.JavaType;
 
 import java.util.List;
+import java.util.function.Predicate;
 
 /**
  * @author freva
  */
 public class JacksonArraySerializer<T> implements FlagSerializer<List<T>> {
     private final JavaType type;
+    private final Predicate<List<T>> validator;
 
-    public JacksonArraySerializer(Class<T> clazz) {
+    public JacksonArraySerializer(Class<T> clazz, Predicate<List<T>> validator) {
         type = JsonNodeRawFlag.constructCollectionType(List.class, clazz);
+        this.validator = validator;
     }
 
     @Override
     public List<T> deserialize(RawFlag rawFlag) {
-        return JsonNodeRawFlag.fromJsonNode(rawFlag.asJsonNode()).toJacksonClass(type);
+        var list = JsonNodeRawFlag.fromJsonNode(rawFlag.asJsonNode()).<List<T>>toJacksonClass(type);
+        if (!validator.test(list)) {
+            throw new IllegalArgumentException("Invalid value: " + list);
+        }
+        return list;
     }
 
     @Override
diff --git a/flags/src/main/java/com/yahoo/vespa/flags/PermanentFlags.java b/flags/src/main/java/com/yahoo/vespa/flags/PermanentFlags.java
index fb807d186eb..19888ec362d 100644
--- a/flags/src/main/java/com/yahoo/vespa/flags/PermanentFlags.java
+++ b/flags/src/main/java/com/yahoo/vespa/flags/PermanentFlags.java
@@ -459,6 +459,7 @@ public class PermanentFlags {
             "log-request-content", List.of(), String.class,
             "Include request content in access log for paths starting with any of these prefixes",
             "Takes effect on next redeployment",
+            list -> list.stream().allMatch(s -> s.matches("^[a-zA-Z/\\.0-9]+:(0(\\.\\d+)?|1(\\.0+)?):\\d+(B|kB|MB|GB)?$")),
             INSTANCE_ID);
 
     private PermanentFlags() {}
@@ -503,5 +504,10 @@ public class PermanentFlags {
         return Flags.defineListFlag(flagId, defaultValue, elementClass, OWNERS, toString(CREATED_AT), toString(EXPIRES_AT), description, modificationEffect, dimensions);
     }
 
+    private static <T> UnboundListFlag<T> defineListFlag(
+            String flagId, List<T> defaultValue, Class<T> elementClass, String description, String modificationEffect, Predicate<List<T>> validator, Dimension... dimensions) {
+        return Flags.defineListFlag(flagId, defaultValue, elementClass, OWNERS, toString(CREATED_AT), toString(EXPIRES_AT), description, modificationEffect, validator, dimensions);
+    }
+
     private static String toString(Instant instant) { return DateTimeFormatter.ISO_DATE.withZone(ZoneOffset.UTC).format(instant); }
 }
diff --git a/flags/src/main/java/com/yahoo/vespa/flags/UnboundListFlag.java b/flags/src/main/java/com/yahoo/vespa/flags/UnboundListFlag.java
index f88a0648021..8411a286d54 100644
--- a/flags/src/main/java/com/yahoo/vespa/flags/UnboundListFlag.java
+++ b/flags/src/main/java/com/yahoo/vespa/flags/UnboundListFlag.java
@@ -2,6 +2,7 @@
 package com.yahoo.vespa.flags;
 
 import java.util.List;
+import java.util.function.Predicate;
 
 /**
  * @author freva
@@ -12,8 +13,13 @@ public class UnboundListFlag<T> extends UnboundFlagImpl<List<T>, ListFlag<T>, Un
     }
 
     public UnboundListFlag(FlagId id, List<T> defaultValue, Class<T> clazz, FetchVector defaultFetchVector) {
+        this(id, defaultValue, clazz, defaultFetchVector, __ -> true);
+    }
+
+    public UnboundListFlag(FlagId id, List<T> defaultValue, Class<T> clazz, FetchVector defaultFetchVector,
+                           Predicate<List<T>> validator) {
         super(id, defaultValue, defaultFetchVector,
-                new JacksonArraySerializer<T>(clazz),
+                new JacksonArraySerializer<T>(clazz, validator),
                 (flagId, defVal, fetchVector) -> new UnboundListFlag<>(flagId, defVal, clazz, fetchVector),
                 ListFlag::new);
     }