generate: migrate config describing/altering to enums

Besides ErrorCode, there may be one or two enums lurking out there.
Known:
  - Op on incremental alter, but I don't think this is worth switching?
  - Mechanism on the new SCRAM apis.

generate/definitions/32_describe_configs

@@ -5,8 +5,7 @@ DescribeConfigsRequest => key 32, max version 3
   // Resources is a list of resources to describe.
   Resources: [=>]
     // ResourceType is an enum corresponding to the type of config to describe.
-    // Valid values are 2 (topic), 4 (broker), or 8 (broker logger).
-    ResourceType: int8
+    ResourceType: enum-ConfigResourceType
     // ResourceName is the name of config to describe.
     //
     // If the requested type is a topic, this corresponds to a topic name.
@@ -53,7 +52,7 @@ DescribeConfigsResponse =>
     // ErrorMessage is an informative message if the describe config failed.
     ErrorMessage: nullable-string
     // ResourceType is the enum corresponding to the type of described config.
-    ResourceType: int8
+    ResourceType: enum-ConfigResourceType
     // ResourceName is the name corresponding to the describe config request.
     ResourceName: string
     // Configs contains information about key/value config pairs for
@@ -69,24 +68,8 @@ DescribeConfigsResponse =>
       // IsDefault is whether this is a default config option. This has been
       // replaced in favor of Source.
       IsDefault: bool // v0-v0
-      // Source is where this config entry is from. Note that if there
-      // are no config synonyms, the source is DEFAULT_CONFIG. The values of
-      // this enum are as follows.
-      //
-      // UNKNOWN (0): unknown; e.g. an altar request was issued with no source set
-      //
-      // DYNAMIC_TOPIC_CONFIG (1): dynamic topic config for a specific topic
-      //
-      // DYNAMIC_BROKER_CONFIG (2): dynamic broker config for a specific broker
-      //
-      // DYNAMIC_DEFAULT_BROKER_CONFIG (3): dynamic broker config used as the default for all brokers in a cluster
-      //
-      // STATIC_BROKER_CONFIG (4): static broker config provided at start up
-      //
-      // DEFAULT_CONFIG (5): built-in default configuration for those that have defaults
-      //
-      // DYNAMIC_BROKER_LOGGER_CONFIG (6): broker logger; see KIP 412.
-      Source: int8(-1) // v1+
+      // Source is where this config entry is from.
+      Source: enum-ConfigSource(-1) // v1+
       // IsSensitive signifies whether this is a sensitive config key, which
       // is either a password or an unknown type.
       IsSensitive: bool
@@ -95,10 +78,8 @@ DescribeConfigsResponse =>
       ConfigSynonyms: [=>] // v1+
         Name: string
         Value: nullable-string
-        Source: int8
-      // ConfigType specifies the configuration data type. The values of this
-      // enum are as follows: UNKNOWN (0), BOOLEAN (1), STRING (2), INT (3),
-      // SHORT (4), LONG (5), DOUBLE (6), LIST (7), CLASS (8), PASSWORD (9).
-      ConfigType: int8 // v3+
+        Source: enum-ConfigSource
+      // ConfigType specifies the configuration data type.
+      ConfigType: enum-ConfigType // v3+
       // Documentation is optional documentation for the config entry.
       Documentation: nullable-string // v3+

generate/definitions/33_alter_configs

@@ -16,7 +16,7 @@ AlterConfigsRequest => key 33, max version 1
   Resources: [=>]
     // ResourceType is an enum corresponding to the type of config to alter.
     // The only two valid values are 2 (for topic) and 4 (for broker).
-    ResourceType: int8
+    ResourceType: enum-ConfigResourceType
     // ResourceName is the name of config to alter.
     //
     // If the requested type is a topic, this corresponds to a topic name.
@@ -67,6 +67,6 @@ AlterConfigsResponse =>
     // ErrorMessage is an informative message if the alter config failed.
     ErrorMessage: nullable-string
     // ResourceType is the enum corresponding to the type of altered config.
-    ResourceType: int8
+    ResourceType: enum-ConfigResourceType
     // ResourceName is the name corresponding to the alter config request.
     ResourceName: string

generate/definitions/44_incremental_alter_configs

@@ -8,9 +8,7 @@ IncrementalAlterConfigsRequest => key 44, max version 1, flexible v1+
   // Resources is an array of configs to alter.
   Resources: [=>]
     // ResourceType is an enum corresponding to the type of config to alter.
-    // The possible valid values are 2 (for topic), 4 (for broker),
-    // and 8 (for broker logger).
-    ResourceType: int8
+    ResourceType: enum-ConfigResourceType
     // ResourceName is the name of config to alter.
     //
     // If the requested type is a topic, this corresponds to a topic name.
@@ -74,7 +72,7 @@ IncrementalAlterConfigsResponse =>
     // ErrorMessage is an informative message if the incremental alter config failed.
     ErrorMessage: nullable-string
     // ResourceType is the enum corresponding to the type of altered config.
-    ResourceType: int8
+    ResourceType: enum-ConfigResourceType
     // ResourceName is the name corresponding to the incremental alter config
     // request.
     ResourceName: string

generate/definitions/enums

@@ -1,3 +1,44 @@
+/////////////
+// CONFIGS //
+/////////////
+
+// A type of config.
+ConfigResourceType int8 (
+  2: TOPIC
+  4: BROKER
+  8: BROKER_LOGGER
+)
+
+// Where a config entry is from. If there are no config synonyms,
+// the source is DEFAULT_CONFIG.
+ConfigSource int8 (
+  // Dynamic topic config for a specific topic.
+  1: DYNAMIC_TOPIC_CONFIG
+  // Dynamic broker config for a specific broker.
+  2: DYNAMIC_BROKER_CONFIG
+  // Dynamic broker config used as the default for all brokers in a cluster.
+  3: DYNAMIC_DEFAULT_BROKER_CONFIG
+  // Static broker config provided at start up.
+  4: STATIC_BROKER_CONFIG
+  // Build-in default configuration for those that have defaults.
+  5: DEFAULT_CONFIG
+  // Broker logger; see KIP-412.
+  6: DYNAMIC_BROKER_LOGGER_CONFIG
+)
+
+// A configuration data type.
+ConfigType int8 (
+  1: BOOLEAN
+  2: STRING
+  3: INT
+  4: SHORT
+  5: LONG
+  6: DOUBLE
+  7: LIST
+  8: CLASS
+  9: PASSWORD
+)
+
 //////////
 // ACLS //
 //////////