core: refine Application interface and add Governance interface (#24)

Add a new Governance interface for interaction with the governance contract.

Also remove the ValidateBlock call in application interface as the application should validate it before putting it into the consensus module.

A new BlockConverter interface is also added. The consensus module should accept the BlockConverter interface in future implementation, and use the Block() function to get the underlying block info.

1 files changed, 6 insertions, 0 deletions

diff --git a/core/types/block.go b/core/types/block.go
index 61b6535..c445fd2 100644
--- a/core/types/block.go
+++ b/core/types/block.go
@@ -50,6 +50,12 @@ type Block struct {
 	Status          Status                   `json:"-"`
 }
 
+// BlockConverter interface define the interface for extracting block
+// information from an existing object.
+type BlockConverter interface {
+	Block() *Block
+}
+
 func (b *Block) String() string {
 	return fmt.Sprintf("Block(%v)", b.Hash.String()[:6])
 }