reload NPE

Author: yanhuqing666

src/main/java/com/actiontech/dble/backend/datasource/PhysicalDBPool.java

@@ -347,6 +347,10 @@ private String getMessage(int index, String info) {
     }
 
     private boolean initSource(int index, PhysicalDatasource ds) {
+        if (ds.getConfig().isFake()) {
+            LOGGER.info(ds.getConfig().getHostName() + " has not real url, skipped");
+            return true;
+        }
         int initSize = ds.getConfig().getMinCon();
         if (initSize == 0) {
             return true;

src/main/java/com/actiontech/dble/config/ConfigInitializer.java

@@ -155,10 +155,9 @@ private void selfChecking0() throws ConfigException {
 
     private void checkWriteHost() {
         for (Map.Entry<String, PhysicalDBPool> pool : this.dataHosts.entrySet()) {
-            this.dataHostWithoutWH = false;
-            if (pool.getValue().getSources() == null || pool.getValue().getSources().length == 0) {
-                LOGGER.info("dataHost " + pool.getKey() + " has no writeHost ,server will ignore it");
-                this.dataHostWithoutWH = true;
+            PhysicalDatasource[] writeSource = pool.getValue().getSources();
+            if (writeSource != null && writeSource.length != 0 && !writeSource[0].getConfig().isFake()) {
+                this.dataHostWithoutWH = false;
                 break;
             }
         }

src/main/java/com/actiontech/dble/config/loader/xml/XMLSchemaLoader.java

@@ -562,6 +562,7 @@ private void loadDataHosts(Element root) {
             final String heartbeatSQL = element.getElementsByTagName("heartbeat").item(0).getTextContent();
 
             NodeList writeNodes = element.getElementsByTagName("writeHost");
+            NodeList readOnlyNodes = element.getElementsByTagName("readHost");
             if (writeNodes.getLength() > 0) {
                 DBHostConfig[] writeDbConfs = new DBHostConfig[writeNodes.getLength()];
                 Map<Integer, DBHostConfig[]> readHostsMap = new HashMap<>(2);
@@ -587,25 +588,39 @@ private void loadDataHosts(Element root) {
                 hostConf.setBalance(balance);
                 hostConf.setHearbeatSQL(heartbeatSQL);
                 dataHosts.put(hostConf.getName(), hostConf);
-            } else { //read host only
-                NodeList readNodes = element.getElementsByTagName("readHost");
+            } else if (readOnlyNodes.getLength() > 0) { //read host only
+                if (readOnlyNodes.getLength() > 1) {
+                    LOGGER.info("only the first Read_Node will be load, others will be ignore");
+                }
                 DBHostConfig[] writeDbConfs = new DBHostConfig[1];
                 writeDbConfs[0] = new DBHostConfig("fakeHost", "-", 0, "-:0)", "-", "-");
                 writeDbConfs[0].setFake(true);
                 DBHostConfig[] readDbConfs = new DBHostConfig[1];
-                Element readNode = (Element) readNodes.item(0);
+                Element readNode = (Element) readOnlyNodes.item(0);
                 readDbConfs[0] = createDBHostConf(name, readNode, maxCon, minCon);
                 Map<Integer, DBHostConfig[]> readHostsMap = new HashMap<>(1);
                 readHostsMap.put(0, readDbConfs);
-
                 DataHostConfig hostConf = new DataHostConfig(name,
                         writeDbConfs, readHostsMap, -1, slaveThreshold, true); // switchType =-1 and tempReadHostAvailable =true
-
                 hostConf.setMaxCon(maxCon);
                 hostConf.setMinCon(minCon);
                 hostConf.setBalance(3); // all read host
                 hostConf.setHearbeatSQL("select 1"); //for heartbeat
                 dataHosts.put(hostConf.getName(), hostConf);
+            } else {
+                DBHostConfig[] writeDbConfs = new DBHostConfig[1];
+                writeDbConfs[0] = new DBHostConfig("fakeHost", "-", 0, "-:0)", "-", "-");
+                writeDbConfs[0].setFake(true);
+                Map<Integer, DBHostConfig[]> readHostsMap = new HashMap<>(0);
+                DataHostConfig hostConf = new DataHostConfig(name,
+                        writeDbConfs, readHostsMap, switchType, slaveThreshold, tempReadHostAvailable);
+
+                hostConf.setMaxCon(maxCon);
+                hostConf.setMinCon(minCon);
+                hostConf.setBalance(balance);
+                hostConf.setHearbeatSQL(heartbeatSQL);
+                dataHosts.put(hostConf.getName(), hostConf);
+                dataHosts.put(hostConf.getName(), hostConf);
             }
         }
     }

src/main/java/com/actiontech/dble/manager/response/ReloadConfig.java

@@ -264,32 +264,35 @@ public static void reloadAll(final int loadAllMode) throws Exception {
          */
         ConfigInitializer loader;
         try {
-            loader = new ConfigInitializer(true, DbleServer.getInstance().getSystemVariables().isLowerCaseTableNames());
+            loader = new ConfigInitializer(true, false);
         } catch (Exception e) {
             throw new Exception(e);
         }
-        Map<String, UserConfig> newUsers = loader.getUsers();
-        Map<String, SchemaConfig> newSchemas = loader.getSchemas();
-        Map<String, PhysicalDBNode> newDataNodes = loader.getDataNodes();
-        Map<String, PhysicalDBPool> newDataHosts = loader.getDataHosts();
-        Map<ERTable, Set<ERTable>> newErRelations = loader.getErRelations();
-        FirewallConfig newFirewall = loader.getFirewall();
 
         SystemVariables newSystemVariables = null;
-        if (!loader.isDataHostWithoutWH()) {
-            VarsExtractorHandler handler = new VarsExtractorHandler(newDataHosts);
-            newSystemVariables = handler.execute();
-            if (newSystemVariables == null) {
+        try {
+            loader.testConnection(false);
+        } catch (Exception e) {
+            if (LOGGER.isDebugEnabled()) {
+                LOGGER.debug("just test ,not stop reload, catch exception", e);
+            }
+        }
+        VarsExtractorHandler handler = new VarsExtractorHandler(loader.getDataHosts());
+        newSystemVariables = handler.execute();
+        if (newSystemVariables == null) {
+            if (!loader.isDataHostWithoutWH()) {
                 throw new IOException("Can't get variables from data node");
+            } else {
+                newSystemVariables = DbleServer.getInstance().getSystemVariables();
             }
-            ConfigInitializer confInit = new ConfigInitializer(newSystemVariables.isLowerCaseTableNames());
-            newUsers = confInit.getUsers();
-            newSchemas = confInit.getSchemas();
-            newDataNodes = confInit.getDataNodes();
-            newErRelations = confInit.getErRelations();
-            newFirewall = confInit.getFirewall();
-            newDataHosts = confInit.getDataHosts();
         }
+        ConfigInitializer confInit = new ConfigInitializer(newSystemVariables.isLowerCaseTableNames());
+        Map<String, UserConfig> newUsers = confInit.getUsers();
+        Map<String, SchemaConfig> newSchemas = confInit.getSchemas();
+        Map<String, PhysicalDBNode> newDataNodes = confInit.getDataNodes();
+        Map<ERTable, Set<ERTable>> newErRelations = confInit.getErRelations();
+        FirewallConfig newFirewall = confInit.getFirewall();
+        Map<String, PhysicalDBPool> newDataHosts = confInit.getDataHosts();
 
         if ((loadAllMode & ManagerParseConfig.OPTT_MODE) != 0) {
             try {