Cleaning up references to the legacy format from the rate limiters lua script

service/src/main/resources/lua/validate_rate_limit.lua

@@ -21,30 +21,13 @@ local changesMade = false
 local tokensRemaining
 local lastUpdateTimeMillis
 
--- while we're migrating from json to redis list key types, there are three possible options for the
+local tokensRemainingStr, lastUpdateTimeMillisStr = unpack(redis.call("HMGET", bucketId, SIZE_FIELD, TIME_FIELD))
--- type of the `bucketId` key: "string" (legacy, json value), "list" (new format), "none" (key not set).
+if tokensRemainingStr and lastUpdateTimeMillisStr then
---
--- On a separate note -- the reason we're not using a different key is because Redis Lua requires to list all keys
--- as a script input and we don't want to expose this migration to the script users.
---
--- Finally, it's okay to read the "ok" key of the return here because "TYPE" command always succeeds.
-local keyType = redis.call("TYPE", bucketId)["ok"]
-if keyType == "none" then
-    -- if the key is not set, building the object from the configuration
-    tokensRemaining = bucketSize
-    lastUpdateTimeMillis = currentTimeMillis
-elseif keyType == "string" then
-    -- if the key is "string", we parse the value from json
-    local fromJson = cjson.decode(redis.call("GET", bucketId))
-    tokensRemaining = fromJson.spaceRemaining
-    lastUpdateTimeMillis = fromJson.lastUpdateTimeMillis
-    redis.call("DEL", bucketId)
-    changesMade = true
-elseif keyType == "hash" then
-    -- finally, reading values from the new storage format
-    local tokensRemainingStr, lastUpdateTimeMillisStr = unpack(redis.call("HMGET", bucketId, SIZE_FIELD, TIME_FIELD))
     tokensRemaining = tonumber(tokensRemainingStr)
     lastUpdateTimeMillis = tonumber(lastUpdateTimeMillisStr)
+else
+    tokensRemaining = bucketSize
+    lastUpdateTimeMillis = currentTimeMillis
 end
 
 local elapsedTime = currentTimeMillis - lastUpdateTimeMillis

service/src/test/java/org/whispersystems/textsecuregcm/limits/RateLimitersLuaScriptTest.java

@@ -69,50 +69,6 @@ public class RateLimitersLuaScriptTest {
     assertThrows(RateLimitExceededException.class, () -> rateLimiter.validate("test", 25));
   }
 
-  @Test
-  public void testFormatMigration() throws Exception {
-    final RateLimiters.For descriptor = RateLimiters.For.REGISTRATION;
-    final FaultTolerantRedisCluster redisCluster = REDIS_CLUSTER_EXTENSION.getRedisCluster();
-    final RateLimiters limiters = new RateLimiters(
-        Map.of(descriptor.id(), new RateLimiterConfig(60, Duration.ofSeconds(1))),
-        dynamicConfig,
-        RateLimiters.defaultScript(redisCluster),
-        redisCluster,
-        Clock.systemUTC());
-
-    final RateLimiter rateLimiter = limiters.forDescriptor(descriptor);
-
-    // embedding an existing value in the old format
-    redisCluster.useCluster(c -> c.sync().set(
-        StaticRateLimiter.bucketName(descriptor.id(), "test"),
-        serializeToOldBucketValueFormat(60, 60, 30, System.currentTimeMillis() + 10000)
-    ));
-    assertThrows(RateLimitExceededException.class, () -> rateLimiter.validate("test", 40));
-
-    // embedding an existing value in the old format
-    redisCluster.useCluster(c -> c.sync().set(
-        StaticRateLimiter.bucketName(descriptor.id(), "test1"),
-        serializeToOldBucketValueFormat(60, 60, 30, System.currentTimeMillis() + 10000)
-    ));
-    rateLimiter.validate("test1", 20);
-    assertThrows(RateLimitExceededException.class, () -> rateLimiter.validate("test1", 20));
-
-    // embedding an existing value in the new format
-    redisCluster.useCluster(c -> c.sync().hset(
-        StaticRateLimiter.bucketName(descriptor.id(), "test2"),
-        Map.of("s", "30", "t", String.valueOf(System.currentTimeMillis() + 10000))
-    ));
-    assertThrows(RateLimitExceededException.class, () -> rateLimiter.validate("test2", 40));
-
-    // embedding an existing value in the new format
-    redisCluster.useCluster(c -> c.sync().hset(
-        StaticRateLimiter.bucketName(descriptor.id(), "test3"),
-        Map.of("s", "30", "t", String.valueOf(System.currentTimeMillis() + 10000))
-    ));
-    rateLimiter.validate("test3", 20);
-    assertThrows(RateLimitExceededException.class, () -> rateLimiter.validate("test3", 20));
-  }
-
   @Test
   public void testTtl() throws Exception {
     final RateLimiters.For descriptor = RateLimiters.For.REGISTRATION;