1 files changed, 45 insertions, 64 deletions
diff --git a/src/interfaces/chain.h b/src/interfaces/chain.h
index fb77c81cdc..7dfc77db7b 100644
--- a/src/interfaces/chain.h
+++ b/src/interfaces/chain.h
@@ -21,6 +21,7 @@ class CScheduler;
 class Coin;
 class uint256;
 enum class RBFTransactionState;
+struct bilingual_str;
 struct CBlockLocator;
 struct FeeCalculation;
 struct NodeContext;
@@ -59,12 +60,7 @@ public:
 //! internal workings of the bitcoin node, and not being very convenient to use.
 //! Chain methods should be cleaned up and simplified over time. Examples:
 //!
-//! * The Chain::lock() method, which lets clients delay chain tip updates
-//!   should be removed when clients are able to respond to updates
-//!   asynchronously
-//!   (https://github.com/bitcoin/bitcoin/pull/10973#issuecomment-380101269).
-//!
-//! * The initMessage() and showProgress() methods which the wallet uses to send
+//! * The initMessages() and showProgress() methods which the wallet uses to send
 //!   notifications to the GUI should go away when GUI and wallet can directly
 //!   communicate with each other without going through the node
 //!   (https://github.com/bitcoin/bitcoin/pull/15288#discussion_r253321096).
@@ -72,68 +68,53 @@ public:
 //! * The handleRpc, registerRpcs, rpcEnableDeprecated methods and other RPC
 //!   methods can go away if wallets listen for HTTP requests on their own
 //!   ports instead of registering to handle requests on the node HTTP port.
+//!
+//! * Move fee estimation queries to an asynchronous interface and let the
+//!   wallet cache it, fee estimation being driven by node mempool, wallet
+//!   should be the consumer.
+//!
+//! * The `guessVerificationProgress`, `getBlockHeight`, `getBlockHash`, etc
+//!   methods can go away if rescan logic is moved on the node side, and wallet
+//!   only register rescan request.
 class Chain
 {
 public:
     virtual ~Chain() {}
 
-    //! Interface for querying locked chain state, used by legacy code that
-    //! assumes state won't change between calls. New code should avoid using
-    //! the Lock interface and instead call higher-level Chain methods
-    //! that return more information so the chain doesn't need to stay locked
-    //! between calls.
-    class Lock
-    {
-    public:
-        virtual ~Lock() {}
-
-        //! Get current chain height, not including genesis block (returns 0 if
-        //! chain only contains genesis block, nullopt if chain does not contain
-        //! any blocks).
-        virtual Optional<int> getHeight() = 0;
-
-        //! Get block height above genesis block. Returns 0 for genesis block,
-        //! 1 for following block, and so on. Returns nullopt for a block not
-        //! included in the current chain.
-        virtual Optional<int> getBlockHeight(const uint256& hash) = 0;
-
-        //! Get block hash. Height must be valid or this function will abort.
-        virtual uint256 getBlockHash(int height) = 0;
-
-        //! Check that the block is available on disk (i.e. has not been
-        //! pruned), and contains transactions.
-        virtual bool haveBlockOnDisk(int height) = 0;
-
-        //! Return height of the first block in the chain with timestamp equal
-        //! or greater than the given time and height equal or greater than the
-        //! given height, or nullopt if there is no block with a high enough
-        //! timestamp and height. Also return the block hash as an optional output parameter
-        //! (to avoid the cost of a second lookup in case this information is needed.)
-        virtual Optional<int> findFirstBlockWithTimeAndHeight(int64_t time, int height, uint256* hash) = 0;
-
-        //! Return height of the specified block if it is on the chain, otherwise
-        //! return the height of the highest block on chain that's an ancestor
-        //! of the specified block, or nullopt if there is no common ancestor.
-        //! Also return the height of the specified block as an optional output
-        //! parameter (to avoid the cost of a second hash lookup in case this
-        //! information is desired).
-        virtual Optional<int> findFork(const uint256& hash, Optional<int>* height) = 0;
-
-        //! Get locator for the current chain tip.
-        virtual CBlockLocator getTipLocator() = 0;
-
-        //! Return height of the highest block on chain in common with the locator,
-        //! which will either be the original block used to create the locator,
-        //! or one of its ancestors.
-        virtual Optional<int> findLocatorFork(const CBlockLocator& locator) = 0;
-
-        //! Check if transaction will be final given chain height current time.
-        virtual bool checkFinalTx(const CTransaction& tx) = 0;
-    };
+    //! Get current chain height, not including genesis block (returns 0 if
+    //! chain only contains genesis block, nullopt if chain does not contain
+    //! any blocks)
+    virtual Optional<int> getHeight() = 0;
+
+    //! Get block height above genesis block. Returns 0 for genesis block,
+    //! 1 for following block, and so on. Returns nullopt for a block not
+    //! included in the current chain.
+    virtual Optional<int> getBlockHeight(const uint256& hash) = 0;
+
+    //! Get block hash. Height must be valid or this function will abort.
+    virtual uint256 getBlockHash(int height) = 0;
+
+    //! Check that the block is available on disk (i.e. has not been
+    //! pruned), and contains transactions.
+    virtual bool haveBlockOnDisk(int height) = 0;
+
+    //! Return height of the first block in the chain with timestamp equal
+    //! or greater than the given time and height equal or greater than the
+    //! given height, or nullopt if there is no block with a high enough
+    //! timestamp and height. Also return the block hash as an optional output parameter
+    //! (to avoid the cost of a second lookup in case this information is needed.)
+    virtual Optional<int> findFirstBlockWithTimeAndHeight(int64_t time, int height, uint256* hash) = 0;
+
+    //! Get locator for the current chain tip.
+    virtual CBlockLocator getTipLocator() = 0;
+
+    //! Return height of the highest block on chain in common with the locator,
+    //! which will either be the original block used to create the locator,
+    //! or one of its ancestors.
+    virtual Optional<int> findLocatorFork(const CBlockLocator& locator) = 0;
 
-    //! Return Lock interface. Chain is locked when this is called, and
-    //! unlocked when the returned interface is freed.
-    virtual std::unique_ptr<Lock> lock(bool try_lock = false) = 0;
+    //! Check if transaction will be final given chain height current time.
+    virtual bool checkFinalTx(const CTransaction& tx) = 0;
 
     //! Return whether node has the block and optionally return block metadata
     //! or contents.
@@ -244,10 +225,10 @@ public:
     virtual void initMessage(const std::string& message) = 0;
 
     //! Send init warning.
-    virtual void initWarning(const std::string& message) = 0;
+    virtual void initWarning(const bilingual_str& message) = 0;
 
     //! Send init error.
-    virtual void initError(const std::string& message) = 0;
+    virtual void initError(const bilingual_str& message) = 0;
 
     //! Send progress indicator.
     virtual void showProgress(const std::string& title, int progress, bool resume_possible) = 0;