more config related cleanup:

- configure electrumX servers with the same mechanisms as everything else
- include _PORT and _ELECTRUMX_SERVERS configs in .env-sample
- drop support for overriding configs via app/credentials.js, and use that filename for the new, dynamic, env-based credentials config file

.env-sample

@@ -1,6 +1,9 @@
 # The active coin: BTC/LTC
 #BTCEXP_COIN = BTC
 
+# Port to run the site on
+#BTCEXP_PORT = 3002
+
 # Bitcoin RPC Credentials (URI -OR- HOST/PORT/USER/PASS)
 #BTCEXP_BITCOIND_URI = bitcoin://rpcusername:rpcpassword@127.0.0.1:8332
 #BTCEXP_BITCOIND_HOST = localhost
@@ -8,7 +11,11 @@
 #BTCEXP_BITCOIND_USER = rpcusername
 #BTCEXP_BITCOIND_PASS = rpcpassword
 
-# Optional: InfluxDB Credentials (URI -OR- HOST/PORT/DBNAME/USER/PASS)
+# Optional ElectrumX Servers, used to display address transaction histories
+# Ref: https://uasf.saltylemon.org/electrum
+#BTCEXP_ELECTRUMX_SERVERS = tls://electrumx.server.com:50002,tcp://127.0.0.1:50001,...
+
+# Optional InfluxDB Credentials (URI -OR- HOST/PORT/DBNAME/USER/PASS)
 #BTCEXP_ENABLE_INFLUXDB = true
 #BTCEXP_INFLUXDB_URI = influx://username:password@127.0.0.1:8086
 #BTCEXP_INFLUXDB_HOST = 127.0.0.1

.gitignore

@@ -59,5 +59,3 @@ typings/
 
 
 public/css/radial-progress.css
-
-app/credentials.js

app/api/electrumApi.js

@@ -57,7 +57,7 @@ function connectToServer(host, port, protocol) {
 		var defaultProtocol = port === 50001 ? 'tcp' : 'tls';
 		var electrumClient = new ElectrumClient(port, host, protocol || defaultProtocol);
 		electrumClient.initElectrum({client:"btc-rpc-explorer-v1.1", version:"1.2"}).then(function(res) {
-			console.log("Connected to ElectrumX Server: " + host + ":" + port + ", versions: " + res);
+			console.log("Connected to ElectrumX Server: " + host + ":" + port + ", versions: " + JSON.stringify(res));
 
 			electrumClients.push(electrumClient);
 

app/config.js

@@ -1,25 +1,12 @@
 var fs = require('fs');
 var crypto = require('crypto');
+var url = require('url');
+
 var coins = require("./coins.js");
+var credentials = require("./credentials.js");
 
 var currentCoin = process.env.BTCEXP_COIN || "BTC";
 
-var credentials = require("./defaultCredentials.js");
-var overrideCredentials = null;
-
-try {
-	Object.assign(overrideCredentials, require("./credentials.js"));
-	
-} catch (err) {
-	// expected
-}
-
-if (overrideCredentials != null) {
-	for (var key in overrideCredentials) {
-		credentials[key] = overrideCredentials[key];
-	}
-}
-
 var rpcCred = credentials.rpc;
 
 if (rpcCred.cookie && !rpcCred.username && !rpcCred.password && fs.existsSync(rpcCred.cookie)) {
@@ -35,6 +22,15 @@ var cookieSecret = process.env.BTCEXP_COOKIE_SECRET
                                .update('btc-rpc-explorer-cookie-secret').digest('hex'))
  || "0x000000000019d6689c085ae165831e934ff763ae46a2a6c172b3f1b60a8ce26f";
 
+
+var electrumXServerUriStrings = (process.env.BTCEXP_ELECTRUMX_SERVERS || "").split(',');
+var electrumXServers = [];
+for (var i = 0; i < electrumXServerUriStrings.length; i++) {
+	var uri = url.parse(electrumXServerUriStrings[i]);
+	
+	electrumXServers.push({protocol:uri.protocol.substring(0, uri.protocol.length - 1), host:uri.hostname, port:parseInt(uri.port)});
+}
+
 module.exports = {
 	cookieSecret: cookieSecret,
 	demoSite: !!process.env.BTCEXP_DEMO,
@@ -107,12 +103,7 @@ module.exports = {
 		"walletpassphrasechange",
 	],
 
-	// https://uasf.saltylemon.org/electrum
-	electrumXServers:[
-		// set host & port of electrum servers to connect to
-		// protocol can be "tls" or "tcp", it defaults to "tcp" if port is 50001 and "tls" otherwise
-		// {host: "electrum.example.com", port:50002, protocol: "tls"}, ...
-	],
+	electrumXServers:electrumXServers,
 
 	site: {
 		blockTxPageSize:20,