btclightclient: Add BaseHeader query (#130)

proto/babylon/btclightclient/query.proto

@@ -31,10 +31,14 @@ service Query {
  option (google.api.http).get = "/babylon/btclightclient/v1/mainchain";
  }
 
- // BestHeader return best header on canonical chain
+ // Tip return best header on canonical chain
  rpc Tip(QueryTipRequest) returns (QueryTipResponse) {
  option (google.api.http).get = "/babylon/btclightclient/v1/tip";
  }
+
+ rpc BaseHeader(QueryBaseHeaderRequest) returns (QueryBaseHeaderResponse) {
+ option (google.api.http).get = "/babylon/btclightclient/v1/baseheader";
+ }
 }
 
 // QueryParamsRequest is request type for the Query/Params RPC method.
@@ -91,3 +95,10 @@ message QueryTipRequest {
 message QueryTipResponse {
  BTCHeaderInfo header = 1;
 }
+
+message QueryBaseHeaderRequest {
+}
+
+message QueryBaseHeaderResponse {
+ BTCHeaderInfo header = 1;
+}

x/btclightclient/client/cli/query.go

@@ -26,6 +26,7 @@ func GetQueryCmd(queryRoute string) *cobra.Command {
  cmd.AddCommand(CmdContains())
  cmd.AddCommand(CmdMainChain())
  cmd.AddCommand(CmdTip())
+ cmd.AddCommand(CmdBaseHeader())
 
  return cmd
 }
@@ -146,7 +147,7 @@ func CmdMainChain() *cobra.Command {
 func CmdTip() *cobra.Command {
  cmd := &cobra.Command{
  Use: "tip",
- Short: "retrieve tip of btc blockchain",
+ Short: "retrieve tip of the bitcoin blockchain",
  Args: cobra.NoArgs,
  RunE: func(cmd *cobra.Command, args []string) error {
  clientCtx := client.GetClientContextFromCmd(cmd)
@@ -167,3 +168,28 @@ func CmdTip() *cobra.Command {
 
  return cmd
 }
+
+func CmdBaseHeader() *cobra.Command {
+ cmd := &cobra.Command{
+ Use: "base-header",
+ Short: "retrieve base header of the bitcoin blockchain",
+ Args: cobra.NoArgs,
+ RunE: func(cmd *cobra.Command, args []string) error {
+ clientCtx := client.GetClientContextFromCmd(cmd)
+
+ queryClient := types.NewQueryClient(clientCtx)
+
+ params := types.NewQueryBaseHeaderRequest()
+ res, err := queryClient.BaseHeader(context.Background(), params)
+ if err != nil {
+ return err
+ }
+
+ return clientCtx.PrintProto(res)
+ },
+ }
+
+ flags.AddQueryFlagsToCmd(cmd)
+
+ return cmd
+}

x/btclightclient/keeper/grpc_query.go

@@ -160,3 +160,15 @@ func (k Keeper) Tip(ctx context.Context, req *types.QueryTipRequest) (*types.Que
 
  return &types.QueryTipResponse{Header: tip}, nil
 }
+
+func (k Keeper) BaseHeader(ctx context.Context, req *types.QueryBaseHeaderRequest) (*types.QueryBaseHeaderResponse, error) {
+ if req == nil {
+ return nil, status.Error(codes.InvalidArgument, "invalid request")
+ }
+
+ sdkCtx := sdk.UnwrapSDKContext(ctx)
+
+ baseHeader := k.headersState(sdkCtx).GetBaseBTCHeader()
+
+ return &types.QueryBaseHeaderResponse{Header: baseHeader}, nil
+}

x/btclightclient/keeper/grpc_query_test.go

@@ -318,6 +318,86 @@ func FuzzMainChainQuery(f *testing.F) {
  })
 }
 
+func FuzzTipQuery(f *testing.F) {
+ /*
+ Checks:
+ 1. If the request is nil, (nil, error) is returned
+ 2. The query returns the tip BTC header
+
+ Data generation:
+ - Generate a random tree of headers and insert into storage
+ */
+ datagen.AddRandomSeedsToFuzzer(f, 100)
+ f.Fuzz(func(t *testing.T, seed int64) {
+ rand.Seed(seed)
+ blcKeeper, ctx := testkeeper.BTCLightClientKeeper(t)
+ sdkCtx := sdk.WrapSDKContext(ctx)
+
+ // Test nil input
+ resp, err := blcKeeper.Tip(sdkCtx, nil)
+ if resp != nil {
+ t.Errorf("Nil input led to a non-nil response")
+ }
+ if err == nil {
+ t.Errorf("Nil input led to a nil error")
+ }
+
+ tree := genRandomTree(blcKeeper, ctx, 1, 10)
+
+ query := types.NewQueryTipRequest()
+ resp, err = blcKeeper.Tip(sdkCtx, query)
+ if err != nil {
+ t.Errorf("valid input led to an error: %s", err)
+ }
+ if resp == nil {
+ t.Errorf("Valid input led to nil response")
+ }
+ if !resp.Header.Eq(tree.GetTip()) {
+ t.Errorf("Invalid header returned. Expected %s, got %s", tree.GetTip().Hash, resp.Header.Hash)
+ }
+ })
+}
+
+func FuzzBaseHeaderQuery(f *testing.F) {
+ /*
+ Checks:
+ 1. If the request is nil, (nil, error) is returned
+ 2. The query returns the base BTC header
+
+ Data generation:
+ - Generate a random tree of headers and insert into storage.
+ */
+ datagen.AddRandomSeedsToFuzzer(f, 100)
+ f.Fuzz(func(t *testing.T, seed int64) {
+ rand.Seed(seed)
+ blcKeeper, ctx := testkeeper.BTCLightClientKeeper(t)
+ sdkCtx := sdk.WrapSDKContext(ctx)
+
+ // Test nil input
+ resp, err := blcKeeper.BaseHeader(sdkCtx, nil)
+ if resp != nil {
+ t.Errorf("Nil input led to a non-nil response")
+ }
+ if err == nil {
+ t.Errorf("Nil input led to a nil error")
+ }
+
+ tree := genRandomTree(blcKeeper, ctx, 1, 10)
+
+ query := types.NewQueryBaseHeaderRequest()
+ resp, err = blcKeeper.BaseHeader(sdkCtx, query)
+ if err != nil {
+ t.Errorf("valid input led to an error: %s", err)
+ }
+ if resp == nil {
+ t.Errorf("Valid input led to nil response")
+ }
+ if !resp.Header.Eq(tree.GetRoot()) {
+ t.Errorf("Invalid header returned. Expected %s, got %s", tree.GetRoot().Hash, resp.Header.Hash)
+ }
+ })
+}
+
 // Constructors for PageRequest objects
 func constructRequestWithKeyAndLimit(key []byte, limit uint64) *query.PageRequest {
  // If limit is 0, set one randomly

x/btclightclient/types/querier.go

@@ -32,3 +32,7 @@ func NewQueryMainChainRequest(req *query.PageRequest) *QueryMainChainRequest {
 func NewQueryTipRequest() *QueryTipRequest {
  return &QueryTipRequest{}
 }
+
+func NewQueryBaseHeaderRequest() *QueryBaseHeaderRequest {
+ return &QueryBaseHeaderRequest{}
+}