feat(x/gov): extend governance config

CHANGELOG.md

@@ -53,6 +53,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 
 ### Improvements
 
+* (x/gov) [#18428](https://github.com/cosmos/cosmos-sdk/pull/18428) Extend governance config 
 * (x/gov) [#18189](https://github.com/cosmos/cosmos-sdk/pull/18189) Limit the accepted deposit coins for a proposal to the minimum proposal deposit denoms.
 * (x/gov) [#18025](https://github.com/cosmos/cosmos-sdk/pull/18025) Improve `<appd> q gov proposer` by querying directly a proposal instead of tx events. It is an alias of `q gov proposal` as the proposer is a field of the proposal.
 * (client) [#17503](https://github.com/cosmos/cosmos-sdk/pull/17503) Add `client.Context{}.WithAddressCodec`, `WithValidatorAddressCodec`, `WithConsensusAddressCodec` to provide address codecs to the client context. See the [UPGRADING.md](./UPGRADING.md) for more details.

proto/cosmos/gov/module/v1/module.proto

@@ -16,4 +16,12 @@ message Module {
 
   // authority defines the custom module authority. If not set, defaults to the governance module.
   string authority = 2;
+
+  // max_title_len defines the maximum proposal title length.
+  // Defaults to 255 if not explicitly set.
+  uint64 max_title_len = 3;
+
+  // max_summary_len defines the maximum proposal summary length.
+  // Defaults to 10200 if not explicitly set.
+  uint64 max_summary_len = 4;
 }

x/gov/README.md

@@ -308,8 +308,8 @@ the following `JSON` template:
 
 This makes it far easier for clients to support multiple networks.
 
-The metadata has a maximum length that is chosen by the app developer, and
-passed into the gov keeper as a config. The default maximum length in the SDK is 255 characters.
+Fields metadata, title and summary have a maximum length that is chosen by the app developer, and
+passed into the gov keeper as a config. The default maximum length are: for the title 255 characters, for the metadata 255 characters and for summary 10200 characters (40 times the one of the title).
 
 #### Writing a module that uses governance
 

x/gov/keeper/keeper.go

@@ -91,9 +91,18 @@ func NewKeeper(
 		panic(fmt.Sprintf("invalid authority address: %s", authority))
 	}
 
+	defaultConfig := types.DefaultConfig()
+	// If MaxMetadataLen not set by app developer, set to default value.
+	if config.MaxTitleLen == 0 {
+		config.MaxTitleLen = defaultConfig.MaxTitleLen
+	}
 	// If MaxMetadataLen not set by app developer, set to default value.
 	if config.MaxMetadataLen == 0 {
-		config.MaxMetadataLen = types.DefaultConfig().MaxMetadataLen
+		config.MaxMetadataLen = defaultConfig.MaxMetadataLen
+	}
+	// If MaxMetadataLen not set by app developer, set to default value.
+	if config.MaxSummaryLen == 0 {
+		config.MaxSummaryLen = defaultConfig.MaxSummaryLen
 	}
 
 	sb := collections.NewSchemaBuilder(storeService)
@@ -181,6 +190,30 @@ func (k Keeper) ModuleAccountAddress() sdk.AccAddress {
 	return k.authKeeper.GetModuleAddress(types.ModuleName)
 }
 
+// validateProposalLengths checks message metadata, summary and title
+// to have the expected length otherwise returns an error.
+func (k Keeper) validateProposalLengths(metadata, title, summary string) error {
+    if err := k.assertMetadataLength(metadata); err != nil {
+        return err
+    }
+    if err := k.assertSummaryLength(summary); err != nil {
+        return err
+    }
+    if err := k.assertTitleLength(title); err != nil {
+        return err
+    }
+    return nil
+}
+
+// assertTitleLength returns an error if given title length
+// is greater than a pre-defined MaxTitleLen.
+func (k Keeper) assertTitleLength(title string) error {
+	if title != "" && uint64(len(title)) > k.config.MaxTitleLen {
+		return types.ErrMetadataTooLong.Wrapf("got title with length %d", len(title))
+	}
+	return nil
+}
+
 // assertMetadataLength returns an error if given metadata length
 // is greater than a pre-defined MaxMetadataLen.
 func (k Keeper) assertMetadataLength(metadata string) error {
@@ -191,9 +224,9 @@ func (k Keeper) assertMetadataLength(metadata string) error {
 }
 
 // assertSummaryLength returns an error if given summary length
-// is greater than a pre-defined 40*MaxMetadataLen.
-func (keeper Keeper) assertSummaryLength(summary string) error {
-	if summary != "" && uint64(len(summary)) > 40*keeper.config.MaxMetadataLen {
+// is greater than a pre-defined MaxSummaryLen.
+func (k Keeper) assertSummaryLength(summary string) error {
+	if summary != "" && uint64(len(summary)) > k.config.MaxSummaryLen {
 		return types.ErrSummaryTooLong.Wrapf("got summary with length %d", len(summary))
 	}
 	return nil