Soul網關原始碼分析-0期(預熱)

啟動 soul-admin成功后, 啟動soul-bootstrap

soul-admin下列印幾行資訊

2021-01-13 23:00:42.047  INFO 16544 --- [0.0-9095-exec-1] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring DispatcherServlet 'dispatcherServlet'
2021-01-13 23:00:42.047  INFO 16544 --- [0.0-9095-exec-1] o.s.web.servlet.DispatcherServlet        : Initializing Servlet 'dispatcherServlet'
2021-01-13 23:00:42.113  INFO 16544 --- [0.0-9095-exec-1] o.s.web.servlet.DispatcherServlet        : Completed initialization in 65 ms
2021-01-13 23:00:42.267  INFO 16544 --- [0.0-9095-exec-1] o.d.s.a.l.websocket.WebsocketCollector   : websocket on open successful....

說明網關與配置后臺建立websocket通信, soul-admin 的 WebsocketCollector 列印出關鍵資訊

@Slf4j
@ServerEndpoint("/websocket")
public class WebsocketCollector {

    private static final Set<Session> SESSION_SET = new CopyOnWriteArraySet<>();

    private static Session session;

    /**
     * On open.
     *
     * @param session the session
     */
    @OnOpen
    public void onOpen(final Session session) {
        log.info("websocket on open successful....");
        SESSION_SET.add(session);
    }
    ...
}

初步判斷, 配置的同步, 默認下是借由websocket協議完成.

再繼續看soul-bootstrap這邊, 由WebsocketSyncDataConfiguration與WebsocketSyncDataService 完成websocket協議建立, 之后也可能借此進行配置通信, 先暫時標記, 以后研究配置同步時繼續鉆研.

2021-01-13 23:00:41.679  INFO 21212 --- [           main] b.s.s.d.w.WebsocketSyncDataConfiguration : you use websocket sync soul data.......
2021-01-13 23:00:42.244  INFO 21212 --- [           main] o.d.s.p.s.d.w.WebsocketSyncDataService   : websocket connection is successful.....

由于網關已經啟動, 埠是9195, 隨便在網址上訪問下 localhost:9195 , 回傳

{
    code: -107,
    message: "Can not find selector, please check your configuration!",
    data: null
}

這時網關列印出日志

2021-01-13 23:06:49.346 ERROR 21212 --- [-work-threads-1] o.d.soul.plugin.base.utils.CheckUtils    : can not match selector data: divide

關鍵類CheckUtils 作為提供selector的工具類, 追溯呼叫它的方法為 AbstractSoulPlugin 的 handleSelectorIsNull

private Mono<Void> handleSelectorIsNull(final String pluginName, final ServerWebExchange exchange, final SoulPluginChain chain) {
    if (PluginEnum.WAF.getName().equals(pluginName)) {
        return doExecute(exchange, chain, null, null);
    }
    return CheckUtils.checkSelector(pluginName, exchange, chain);
}

WAF? 看著像匹配并執行防火墻類的插件的實作方法 (doExecute()被繼承類實作, 模板方法 ), 然后獲得selector, 這里的selector是啥不明白, 暫放一邊, 繼續向上查看呼叫, 發現是該類的execute()方法呼叫的.

@Override
public Mono<Void> execute(final ServerWebExchange exchange, final SoulPluginChain chain) {
    String pluginName = named();
    final PluginData pluginData = BaseDataCache.getInstance().obtainPluginData(pluginName);
    if (pluginData != null && pluginData.getEnabled()) {
        final Collection<SelectorData> selectors = BaseDataCache.getInstance().obtainSelectorData(pluginName);
        if (CollectionUtils.isEmpty(selectors)) {
            return handleSelectorIsNull(pluginName, exchange, chain);
        }
        final SelectorData selectorData = matchSelector(exchange, selectors);
        if (Objects.isNull(selectorData)) {
            return handleSelectorIsNull(pluginName, exchange, chain);
        }
        selectorLog(selectorData, pluginName);
        final List<RuleData> rules = BaseDataCache.getInstance().obtainRuleData(selectorData.getId());
        if (CollectionUtils.isEmpty(rules)) {
            return handleRuleIsNull(pluginName, exchange, chain);
        }
        RuleData rule;
        if (selectorData.getType() == SelectorTypeEnum.FULL_FLOW.getCode()) {
            //get last
            rule = rules.get(rules.size() - 1);
        } else {
            rule = matchRule(exchange, rules);
        }
        if (Objects.isNull(rule)) {
            return handleRuleIsNull(pluginName, exchange, chain);
        }
        ruleLog(rule, pluginName);
        return doExecute(exchange, chain, selectorData, rule);
    }
    return chain.execute(exchange);
}

execute方法在我看來, 就是所有插件的祖宗級入口, 方法由介面 SoulPlugin 定義, 這個介面應該是祖宗類, 這個方法應該是重點, 暫時也不研究, 在研究插件時, 看這里.

再看下AbstractSoulPlugin 被哪些插件類繼承了, 看到個熟悉的影子 DividePlugin , 和剛剛日志列印的 can not match selector data: divide有關系, 盲猜剛剛日志列印時, AbstractSoulPlugin的實作類是它, 開始debug, 先直接D在CheckUtils列印那行

public static Mono<Void> checkSelector(final String pluginName, final ServerWebExchange exchange, final SoulPluginChain chain) {
    if (PluginEnum.DIVIDE.getName().equals(pluginName)
        || PluginEnum.DUBBO.getName().equals(pluginName)
        || PluginEnum.SPRING_CLOUD.getName().equals(pluginName)) {
        log.error("can not match selector data: {}", pluginName);
        Object error = SoulResultWrap.error(SoulResultEnum.CANNOT_FIND_SELECTOR.getCode(), SoulResultEnum.CANNOT_FIND_SELECTOR.getMsg(), null);
        return WebFluxResultUtils.result(exchange, error);
    }
    return chain.execute(exchange);
}

對著執行緒堆疊向上追兩個呼叫, 到AbstractSoulPlugin這層, 發現實際的實作類確實是 DividePlugin , 那它的具體 doExecute() 的實作, 就是去處理得到的 Selector 了. 暫時不看, 該睡覺了…

明天將一個http服務跑起來, 看看有什么關鍵類在作用, 以及最重要的網關server和client如何作業