Retrieve blockchain state before opening the DB

This would make sure that bitcoind is up and running.

src/app.rs

@@ -101,6 +101,7 @@ impl App {
 fn run_server(config: &Config) -> Result<()> {
     let index = index::Index::new();
     let daemon = daemon::Daemon::new(config.network_type)?;
+    debug!("{:?}", daemon.getblockchaininfo()?);
 
     let store = store::DBStore::open(
         config.db_path,

src/daemon.rs

@@ -5,7 +5,7 @@ use bitcoin::network::serialize::BitcoinHash;
 use bitcoin::network::serialize::{deserialize, serialize};
 use bitcoin::util::hash::Sha256dHash;
 use hex;
-use serde_json::{from_str, Value};
+use serde_json::{from_str, from_value, Value};
 use std::env::home_dir;
 use std::fs;
 use std::io::{BufRead, BufReader, Write};
@@ -49,6 +49,16 @@ pub struct MempoolEntry {
     fee_per_vbyte: f32,
 }
 
+#[derive(Serialize, Deserialize, Debug)]
+pub struct BlockchainInfo {
+    chain: String,
+    blocks: usize,
+    headers: usize,
+    bestblockhash: String,
+    size_on_disk: usize,
+    pruned: bool,
+}
+
 impl MempoolEntry {
     fn new(fee: u64, vsize: u32) -> MempoolEntry {
         MempoolEntry {
@@ -144,6 +154,11 @@ impl Daemon {
 
     // bitcoind JSONRPC API:
 
+    pub fn getblockchaininfo(&self) -> Result<BlockchainInfo> {
+        let info: Value = self.request("getblockchaininfo", json!([]))?;
+        Ok(from_value(info).chain_err(|| "invalid blockchain info")?)
+    }
+
     pub fn getbestblockhash(&self) -> Result<Sha256dHash> {
         parse_hash(&self.request("getbestblockhash", json!([]))?).chain_err(|| "invalid blockhash")
     }