feat(spv): add checkpoints and start sync from last checkpoint (#165,…

contrib/fetch_checkpoints.sh

@@ -0,0 +1,200 @@
+#!/bin/sh
+# Fetch checkpoint data from Dash network
+#
+# This script fetches block information at specific heights to create checkpoints
+# for the rust-dashcore SPV client.
+#
+# Usage:
+#   # Fetch specific heights using block explorer
+#   ./fetch_checkpoints.sh mainnet 2400000 2450000
+#
+#   # Fetch using RPC (requires running Dash Core node)
+#   RPC_URL=http://localhost:9998 RPC_USER=user RPC_PASS=pass ./fetch_checkpoints.sh mainnet 2400000
+
+set -e
+
+NETWORK=${1:-mainnet}
+shift || true
+
+# Configuration
+if [ "$NETWORK" = "mainnet" ]; then
+    EXPLORER_URL="https://insight.dash.org/insight-api"
+elif [ "$NETWORK" = "testnet" ]; then
+    EXPLORER_URL="https://testnet-insight.dashevo.org/insight-api"
+else
+    echo "Error: Invalid network. Use 'mainnet' or 'testnet'"
+    exit 1
+fi
+
+# Check for required tools
+if ! command -v curl >/dev/null 2>&1; then
+    echo "Error: curl is required but not installed"
+    exit 1
+fi
+
+if ! command -v jq >/dev/null 2>&1; then
+    echo "Error: jq is required but not installed. Install with: sudo apt install jq"
+    exit 1
+fi
+
+# Function to get current blockchain height
+get_current_height() {
+    if [ -n "$RPC_URL" ] && [ -n "$RPC_USER" ] && [ -n "$RPC_PASS" ]; then
+        # Use RPC
+        curl -s -u "$RPC_USER:$RPC_PASS" \
+            -H "Content-Type: application/json" \
+            -d '{"jsonrpc":"2.0","id":"checkpoint","method":"getblockchaininfo","params":[]}' \
+            "$RPC_URL" | jq -r '.result.blocks'
+    else
+        # Use explorer
+        curl -s "$EXPLORER_URL/status?q=getInfo" | jq -r '.info.blocks'
+    fi
+}
+
+# Function to get block by height using explorer
+get_block_explorer() {
+    height=$1
+
+    # Get block hash at height
+    block_hash=$(curl -s "$EXPLORER_URL/block-index/$height" | jq -r '.blockHash')
+
+    if [ -z "$block_hash" ] || [ "$block_hash" = "null" ]; then
+        echo "Error: Failed to get block hash for height $height" >&2
+        return 1
+    fi
+
+    # Get full block data
+    curl -s "$EXPLORER_URL/block/$block_hash"
+}
+
+# Function to get block by height using RPC
+get_block_rpc() {
+    height=$1
+
+    # Get block hash
+    block_hash=$(curl -s -u "$RPC_USER:$RPC_PASS" \
+        -H "Content-Type: application/json" \
+        -d "{\"jsonrpc\":\"2.0\",\"id\":\"checkpoint\",\"method\":\"getblockhash\",\"params\":[$height]}" \
+        "$RPC_URL" | jq -r '.result')
+
+    if [ -z "$block_hash" ] || [ "$block_hash" = "null" ]; then
+        echo "Error: Failed to get block hash for height $height" >&2
+        return 1
+    fi
+
+    # Get block data
+    curl -s -u "$RPC_USER:$RPC_PASS" \
+        -H "Content-Type: application/json" \
+        -d "{\"jsonrpc\":\"2.0\",\"id\":\"checkpoint\",\"method\":\"getblock\",\"params\":[\"$block_hash\",2]}" \
+        "$RPC_URL" | jq -r '.result'
+}
+
+# Function to format checkpoint as Rust code
+format_checkpoint() {
+    block_json=$1
+
+    height=$(echo "$block_json" | jq -r '.height')
+    hash=$(echo "$block_json" | jq -r '.hash')
+    prev_hash=$(echo "$block_json" | jq -r '.previousblockhash // "0000000000000000000000000000000000000000000000000000000000000000"')
+    timestamp=$(echo "$block_json" | jq -r '.time')
+    bits=$(echo "$block_json" | jq -r '.bits')
+    merkle_root=$(echo "$block_json" | jq -r '.merkleroot')
+    nonce=$(echo "$block_json" | jq -r '.nonce')
+    chain_work=$(echo "$block_json" | jq -r '.chainwork // "0x0000000000000000000000000000000000000000000000000000000000000000"')
+
+    # Ensure chainwork has 0x prefix
+    if ! echo "$chain_work" | grep -q "^0x"; then
+        chain_work="0x$chain_work"
+    fi
+
+    # Convert bits to hex format
+    if echo "$bits" | grep -q "^[0-9a-fA-F]\+$"; then
+        bits_hex="0x$bits"
+    else
+        bits_hex="$bits"
+    fi
+
+    # Format as Rust code
+    cat <<EOF
+        // Block $height ($hash)
+        create_checkpoint(
+            $height,
+            "$hash",
+            "$prev_hash",
+            $timestamp,
+            $bits_hex,
+            "$chain_work",
+            "$merkle_root",
+            $nonce,
+            None,  // TODO: Add masternode list if available (format: Some("ML${height}__<protocol_version>"))
+        ),
+EOF
+}
+
+# Main script
+echo "Fetching checkpoints for $NETWORK..." >&2
+echo "" >&2
+
+# Get current height
+current_height=$(get_current_height)
+if [ -z "$current_height" ]; then
+    echo "Error: Failed to get current blockchain height" >&2
+    exit 1
+fi
+echo "Current blockchain height: $current_height" >&2
+echo "" >&2
+
+# If no heights specified, show usage
+if [ $# -eq 0 ]; then
+    echo "Usage: $0 <network> <height1> [height2] [height3] ..." >&2
+    echo "" >&2
+    echo "Current height: $current_height" >&2
+    echo "Suggested checkpoint heights:" >&2
+    if [ "$NETWORK" = "mainnet" ]; then
+        echo "  2400000 - Block 2.4M" >&2
+        echo "  2450000 - Block 2.45M" >&2
+        echo "  2500000 - Block 2.5M (if available)" >&2
+    else
+        echo "  1200000 - Block 1.2M" >&2
+        echo "  1300000 - Block 1.3M" >&2
+    fi
+    echo "" >&2
+    echo "Examples:" >&2
+    echo "  $0 mainnet 2400000" >&2
+    echo "  RPC_URL=http://localhost:9998 RPC_USER=user RPC_PASS=pass $0 mainnet 2400000" >&2
+    exit 1
+fi
+
+# Output header
+echo "// Generated checkpoints for $NETWORK"
+echo "// Add these to dash-spv/src/chain/checkpoints.rs"
+echo ""
+
+# Fetch each requested height
+for height in "$@"; do
+    if [ "$height" -gt "$current_height" ]; then
+        echo "// Skipping height $height (exceeds current height $current_height)"
+        continue
+    fi
+
+    echo "Fetching block at height $height..." >&2
+
+    # Get block data
+    if [ -n "$RPC_URL" ] && [ -n "$RPC_USER" ] && [ -n "$RPC_PASS" ]; then
+        block_data=$(get_block_rpc "$height")
+    else
+        block_data=$(get_block_explorer "$height")
+    fi
+
+    if [ $? -ne 0 ] || [ -z "$block_data" ]; then
+        echo "// Error: Failed to fetch block at height $height"
+        continue
+    fi
+
+    # Format and output
+    format_checkpoint "$block_data"
+done
+
+echo ""
+echo "// NOTE: Update masternode_list_name values if the blocks have DML (Deterministic Masternode List)"
+echo "// Check coinbase transaction for masternode list information"

dash-spv/src/chain/checkpoints.rs

@@ -344,6 +344,18 @@ pub fn mainnet_checkpoints() -> Vec<Checkpoint> {
             972444458,
             Some("ML2300000__70232"),
         ),
+        // Block 2350000 (2025) - additional recent checkpoint
+        create_checkpoint(
+            2350000,
+            "00000000000000258216a62e8c7170be1207335474ddfa667092a71e3d4162d2",
+            "000000000000002702e07f9f3402026e4cd5707961ce54af22c873331a329708",
+            1759648416,
+            0x192f2bfb,
+            "0x00000000000000000000000000000000000000000000ada31a5dd056c969c842",
+            "3e77d2ed0c24aab79096d700cdc4fe3ea9502fcec38ee114c81c9063842a6725",
+            3635235496,
+            Some("ML2350000__70232"),
+        ),
     ]
 }