一、Mycat1.6只Schema加载DataHosts完整属性源码解读
private final static String DEFAULT_DTD = "/schema.dtd"; private final static String DEFAULT_XML = "/schema.xml"; public XMLSchemaLoader(String schemaFile, String ruleFile) { //先读取rule.xml XMLRuleLoader ruleLoader = new XMLRuleLoader(ruleFile); //将tableRules拿出，用于这里加载Schema做rule有效判断，以及之后的分片路由计算 this.tableRules = ruleLoader.getTableRules(); //释放ruleLoader ruleLoader = null; this.dataHosts = new HashMap<String, DataHostConfig>(); this.dataNodes = new HashMap<String, DataNodeConfig>(); this.schemas = new HashMap<String, SchemaConfig>(); //读取加载schema配置 this.load(DEFAULT_DTD, schemaFile == null ? DEFAULT_XML : schemaFile); } //加载顺序：主机/节点/ Schema private void load(String dtdFile, String xmlFile) { InputStream dtd = null; InputStream xml = null; dtd = XMLSchemaLoader.class.getResourceAsStream(dtdFile); xml = XMLSchemaLoader.class.getResourceAsStream(xmlFile); Element root = ConfigUtil.getDocument(dtd, xml).getDocumentElement(); //先加载所有的DataHost loadDataHosts(root); //再加载所有的DataNode loadDataNodes(root); //最后加载所有的Schema loadSchemas(root); } /** <dataHost name="localhost1_gaojingsong1" maxCon="1000" minCon="1" balance="0" writeType="0" dbType="db2" dbDriver="jdbc" switchType="-1" slaveThreshold="" tempReadHostAvailable="" filters="" logTime=""> <heartbeat>select 1 from sysibm.sysdummy1</heartbeat> <connectionInitSql>alter session set nls_date_format='yyyy-mm-dd hh24:mi:ss' </connectionInitSql> <writeHost host="hostM1" url="jdbc:db2://19:50000/TEST001" user="db2inst1" password="123456" > </writeHost> </dataHost> */ private void loadDataHosts(Element root) { NodeList list = root.getElementsByTagName("dataHost"); for (int i = 0, n = list.getLength(); i < n; ++i) { Element element = (Element) list.item(i); String name = element.getAttribute("name"); //判断是否重复 if (dataHosts.containsKey(name)) { throw new ConfigException("dataHost name " + name + "duplicated!"); } //读取最大连接数 int maxCon = Integer.parseInt(element.getAttribute("maxCon")); //读取最小连接数 int minCon = Integer.parseInt(element.getAttribute("minCon")); /** * 读取负载均衡配置 * 1. balance="0", 不开启分离机制，所有读操作都发送到当前可用的 writeHost 上。 * 2. balance="1"，全部的 readHost 和 stand by writeHost 参不 select 的负载均衡 * 3. balance="2"，所有读操作都随机的在 writeHost、readhost 上分发。 * 4. balance="3"，所有读请求随机的分发到 wiriterHost 对应的 readhost 执行，writerHost 不负担读压力 */ int balance = Integer.parseInt(element.getAttribute("balance")); /** * 读取切换类型 * -1 表示不自动切换 * 1 默认值，自动切换 * 2 基于MySQL主从同步的状态决定是否切换 * 心跳询句为 show slave status * 3 基于 MySQL galary cluster 的切换机制 */ String switchTypeStr = element.getAttribute("switchType"); int switchType = switchTypeStr.equals("") ? -1 :Integer.parseInt(switchTypeStr); //读取从延迟界限 String slaveThresholdStr = element.getAttribute("slaveThreshold"); int slaveThreshold = slaveThresholdStr.equals("") ? -1 : Integer.parseInt(slaveThresholdStr); //如果 tempReadHostAvailable 设置大于 0 则表示写主机如果挂掉，临时的读服务依然可用 String tempReadHostAvailableStr = element.getAttribute("tempReadHostAvailable"); boolean tempReadHostAvailable = !tempReadHostAvailableStr.equals("") && Integer.parseInt(tempReadHostAvailableStr) > 0; /** * 读取 写类型 * 这里只支持 0 - 所有写操作仅配置的第一个 writeHost */ String writeTypStr = element.getAttribute("writeType"); int writeType = "".equals(writeTypStr) ? PhysicalDBPool.WRITE_ONLYONE_NODE : Integer.parseInt(writeTypStr); String dbDriver = element.getAttribute("dbDriver"); String dbType = element.getAttribute("dbType"); String filters = element.getAttribute("filters"); String logTimeStr = element.getAttribute("logTime"); long logTime = "".equals(logTimeStr) ? PhysicalDBPool.LONG_TIME : Long.parseLong(logTimeStr) ; //读取心跳语句 String heartbeatSQL = element.getElementsByTagName("heartbeat").item(0).getTextContent(); //读取 初始化sql配置,用于oracle NodeList connectionInitSqlList = element.getElementsByTagName("connectionInitSql"); String initConSQL = null; if (connectionInitSqlList.getLength() > 0) { initConSQL = connectionInitSqlList.item(0).getTextContent(); } //读取writeHost /** <writeHost host="hostM1" url="localhost:3306" user="root" password="123456" usingDecrypt="" weight=""> <!-- can have multi read hosts --> <readHost host="hostS2" url="192.168.1.200:3306" user="root" password="xxx" /> </writeHost> */ NodeList writeNodes = element.getElementsByTagName("writeHost"); DBHostConfig[] writeDbConfs = new DBHostConfig[writeNodes.getLength()]; Map<Integer, DBHostConfig[]> readHostsMap = new HashMap<Integer, DBHostConfig[]>(2); for (int w = 0; w < writeDbConfs.length; w++) { Element writeNode = (Element) writeNodes.item(w); writeDbConfs[w] = createDBHostConf(name, writeNode, dbType,dbDriver, maxCon, minCon,filters,logTime); NodeList readNodes = writeNode.getElementsByTagName("readHost"); //读取对应的每一个readHost if (readNodes.getLength() != 0) { DBHostConfig[] readDbConfs = new DBHostConfig[readNodes.getLength()]; for (int r = 0; r < readDbConfs.length; r++) { Element readNode = (Element) readNodes.item(r); readDbConfs[r] = createDBHostConf(name,readNode, dbType, dbDriver, maxCon, minCon,filters, logTime); } readHostsMap.put(w, readDbConfs); } } DataHostConfig hostConf = new DataHostConfig(name, dbType, dbDriver, writeDbConfs, readHostsMap, switchType, slaveThreshold, tempReadHostAvailable); hostConf.setMaxCon(maxCon); hostConf.setMinCon(minCon); hostConf.setBalance(balance); hostConf.setWriteType(writeType); hostConf.setHearbeatSQL(heartbeatSQL); hostConf.setConnectionInitSql(initConSQL); hostConf.setFilters(filters); hostConf.setLogTime(logTime); dataHosts.put(hostConf.getName(), hostConf); } } private DBHostConfig createDBHostConf(String dataHost, Element node, String dbType, String dbDriver, int maxCon, int minCon, String filters, long logTime) { String nodeHost = node.getAttribute("host"); String nodeUrl = node.getAttribute("url"); String user = node.getAttribute("user"); String password = node.getAttribute("password"); String usingDecrypt = node.getAttribute("usingDecrypt"); String passwordEncryty= DecryptUtil.DBHostDecrypt(usingDecrypt, nodeHost, user, password); String weightStr = node.getAttribute("weight"); int weight = "".equals(weightStr) ? PhysicalDBPool.WEIGHT : Integer.parseInt(weightStr) ; String ip = null; int port = 0; if (empty(nodeHost) || empty(nodeUrl) || empty(user)) { throw new ConfigException( "dataHost " + dataHost + " define error,some attributes of this element is empty: " + nodeHost); } if ("native".equalsIgnoreCase(dbDriver)) { int colonIndex = nodeUrl.indexOf(':'); ip = nodeUrl.substring(0, colonIndex).trim(); port = Integer.parseInt(nodeUrl.substring(colonIndex + 1).trim()); } else { URI url; try { url = new URI(nodeUrl.substring(5)); } catch (Exception e) { throw new ConfigException("invalid jdbc url " + nodeUrl + " of " + dataHost); } ip = url.getHost(); port = url.getPort(); } DBHostConfig conf = new DBHostConfig(nodeHost, ip, port, nodeUrl, user, passwordEncryty,password); conf.setDbType(dbType); conf.setMaxCon(maxCon); conf.setMinCon(minCon); conf.setFilters(filters); conf.setLogTime(logTime); conf.setWeight(weight); //新增权重 return conf; } public static String DBHostDecrypt(String usingDecrypt,String host, String user ,String passwrod){ if("1".equals(usingDecrypt)){ //type:host:user:password //1:myhost1:test:test boolean flag = false; try { String passwrods[] = DecryptUtil.decrypt(passwrod).split(":"); if("1".equals(passwrods[0]) && host.equals(passwrods[1]) && user.equals(passwrods[2])){ return passwrods[3]; } if(flag==false){ throw new ConfigException("user " + user + " passwrod need to decrype ,but decrype password is wrong !"); } } catch (Exception e2) { throw new ConfigException("host " + host + ",user " + user + " passwrod need to decrype ,but decrype password is wrong !",e2); } } return passwrod; }
二、总结：
dataHost 完整配置如下：
/**
<dataHost name="localhost1_gaojingsong1" maxCon="1000" minCon="1" balance="0" writeType="0"
dbType="db2" dbDriver="jdbc" switchType="-1" slaveThreshold="" tempReadHostAvailable="" filters="" logTime="">
<heartbeat>select 1 from sysibm.sysdummy1</heartbeat>
<connectionInitSql>alter session set nls_date_format='yyyy-mm-dd hh24:mi:ss'</connectionInitSql>
<writeHost host="hostM1" url="jdbc:db2://192.168.8.129:50000/TEST001" user="db2inst1" password="123456" >
</writeHost>
</dataHost>
*/
//读取writeHost
/**
<writeHost host="hostM1" url="localhost:3306" user="root"
password="123456" usingDecrypt="" weight="">
<!-- can have multi read hosts -->
<readHost host="hostS2" url="192.168.1.200:3306" user="root" password="xxx" usingDecrypt="" weight=""/>
</writeHost>
*/
备注：
writeType 这里只支持 0 - 所有写操作仅配置的第一个 writeHost
/** * balance读取负载均衡配置
* 1. balance="0", 不开启分离机制，所有读操作都发送到当前可用的 writeHost 上。
* 2. balance="1"，全部的 readHost 和 stand by writeHost 参不 select 的负载均衡
* 3. balance="2"，所有读操作都随机的在 writeHost、readhost 上分发。
* 4. balance="3"，所有读请求随机的分发到 wiriterHost 对应的 readhost 执行，
writerHost 不负担读压力
*/
/**
* switchType读取切换类型
* -1 表示不自动切换 * 1 默认值，自动切换
* 2 基于MySQL主从同步的状态决定是否切换
* 心跳询句为 show slave status
* 3 基于 MySQL galary cluster 的切换机制
*/
tempReadHostAvailable 设置大于 0 则表示写主机如果挂掉， 临时的读服务依然可用