引入前缀树，加速url解析，正确处理异常

Author: xenv

README.md

@@ -1,9 +1,6 @@
 ## 一言·古诗词 API
 
-<div style="text-align:center">
 <img src="https://api.gushi.ci/all.svg">
-</div>
-
 
 ### 简介
 
@@ -89,9 +86,8 @@ JSON调用可以获取来源、作者、分类等信息，可以供你自定义
   xhr.open('get', 'https://api.gushi.ci/all.txt');
   xhr.onreadystatechange = function () {
     if (xhr.readyState === 4) {
-      var data = JSON.parse(xhr.responseText);
       var gushici = document.getElementById('gushici');
-      gushici.innerText = data.content;
+      gushici.innerText = xhr.responseText;
     }
   };
   xhr.send();
@@ -112,10 +108,16 @@ TXT调用和JSON调用基本一致，可以节省一些流量。或者，你甚
 4. ConvertUtil 负责转码
 5. Service 没有使用 Service Proxy，因此无需额外生成代码。
 
-### 待改进
+### 更新历史
+
+* 2018.08.06 1.1: 
+  1. 引入前缀树，使分类检索效率由 O(n) (n为所有分类数) 变为 O(L) (L为分类级数)。
+  缺点是空间复杂度由 O(n) 变为 O(nL)，代码复杂度增加60行
+  2. 优化了正则匹配获取地址参数的逻辑
+  3. 正确加入了全局的错误处理（包括 Router 和 EventBus）
+* 2018.08.05 1.0：初始版本，支持 4 种格式返回，支持按分类搜索 
+
 
-1. 错误处理
-2. 优化部分可能会阻塞的代码
 
 ### 关于项目
 

pom.xml

@@ -6,7 +6,7 @@
 
     <groupId>ma.luan</groupId>
     <artifactId>yiyan</artifactId>
-    <version>1.0</version>
+    <version>1.1</version>
 
     <properties>
         <java.version>1.8</java.version>

src/main/java/ma/luan/yiyan/MainVerticle.java

@@ -29,6 +29,9 @@ public void start() {
             .setPort(config().getJsonObject("redis").getInteger("port",6379))
             .setSelect(config().getJsonObject("redis").getInteger("select",0));
 
+        // 配置 RuntimeError 错误记录
+        vertx.exceptionHandler(error -> log.error(error));
+
         // 顺序部署 Verticle
         Future.<Void>succeededFuture()
             .compose(v -> Future.<String>future(s -> vertx.deployVerticle(new ApiVerticle(),new DeploymentOptions().setConfig(config()), s)))

src/main/java/ma/luan/yiyan/api/ApiVerticle.java

@@ -2,6 +2,8 @@
 
 import io.vertx.core.AbstractVerticle;
 import io.vertx.core.Future;
+import io.vertx.core.eventbus.ReplyException;
+import io.vertx.core.eventbus.ReplyFailure;
 import io.vertx.core.http.HttpServerResponse;
 import io.vertx.core.json.JsonArray;
 import io.vertx.core.json.JsonObject;
@@ -14,24 +16,23 @@
 import org.apache.logging.log4j.Logger;
 
 import java.util.Arrays;
-import java.util.regex.Matcher;
-import java.util.regex.Pattern;
+import java.util.stream.Collectors;
 
 public class ApiVerticle extends AbstractVerticle {
-    private Logger log = LogManager.getLogger(this.getClass());
+    //private Logger log = LogManager.getLogger(this.getClass());
 
     @Override
     public void start(Future<Void> startFuture) {
         Router router = Router.router(vertx);
         router.route().handler(BodyHandler.create());
         router.get("/*").handler(this::log); // 全局日志处理，会执行 next() 到下一个
         router.get("/").handler(this::handleRoot); // 首页
-        router.get("/favicon.ico").handler(c -> returnError(c, new Exception("404"))); // 针对浏览器返回404
+        router.get("/favicon.ico").handler(c -> c.fail(404)); // 针对浏览器返回404
         router.get("/log").handler(this::showLog); // 显示日志
-        router.get("/*").handler(this::handleGushici); // 核心API调用
-        router.route().last().handler(c -> { // 其他返回 404 （应该不会走到这里）
-            returnError(c, new Exception("404"));
-        });
+        router.routeWithRegex("/([a-z0-9/]*)\\.?(txt|json|png|svg|)")
+                .handler(this::handleGushici); // 核心API调用
+        router.route().last().handler(c -> c.fail(404)) // 其他返回404
+                .failureHandler(this::returnError); // 对上面所有的错误进行处理
         vertx
             .createHttpServer()
             .requestHandler(router::accept)
@@ -58,25 +59,25 @@ private void handleRoot(RoutingContext routingContext) {
                 result.put("list", res.result().body());
                 returnJsonWithCache(routingContext, result);
             } else {
-                returnError(routingContext, res.cause());
+                routingContext.fail(res.cause());
             }
         });
     }
 
     private void handleGushici(RoutingContext routingContext) {
         // 这里有两层回调，因为第二层回调需要用到第一层回调的数据。
-        parseURI(routingContext.normalisedPath()) // 获取到 URI 上面的参数
+        parseURI(routingContext) // 获取到 URI 上面的参数
             .setHandler(params -> {
                 if (params.succeeded()) {
                     vertx.eventBus().<String>send(Key.GET_GUSHICI_FROM_REDIS, params.result(), res -> { // 从 Redis 拿数据
                         if (res.succeeded()) {
                             returnGushici(routingContext, res.result().body(), params.result());
                         } else {
-                            returnError(routingContext, res.cause());
+                            routingContext.fail(res.cause());
                         }
                     });
                 } else {
-                    returnError(routingContext, params.cause());
+                    routingContext.fail(params.cause());
                 }
             });
     }
@@ -86,7 +87,7 @@ private void showLog(RoutingContext routingContext) {
             if (res.succeeded()) {
                 returnJson(routingContext, res.result().body());
             } else {
-                returnError(routingContext, res.cause());
+                routingContext.fail(res.cause());
             }
         });
     }
@@ -104,15 +105,19 @@ private void returnJsonWithCache(RoutingContext routingContext, JsonObject jsonO
             .end(jsonObject.encodePrettily());
     }
 
-    private void returnError(RoutingContext routingContext, Throwable cause) {
+    private void returnError(RoutingContext routingContext) {
         JsonObject result = new JsonObject();
-        result.put("error", cause.getMessage());
-        int statusCode = cause.getMessage().startsWith("404") ? 404 : 500;
-        if (statusCode == 500) {
-            log.error(cause);
+        int errorCode = routingContext.statusCode() > 0 ? routingContext.statusCode() : 500;
+        // 不懂 Vert.x 为什么 EventBus 和 Web 是两套异常系统
+        if (routingContext.failure() instanceof ReplyException) {
+            errorCode = ((ReplyException) routingContext.failure()).failureCode();
+        }
+        result.put("error-code", errorCode);
+        if (routingContext.failure() != null) {
+            result.put("reason", routingContext.failure().getMessage());
         }
         setCommonHeader(routingContext.response()
-            .setStatusCode(statusCode)
+            .setStatusCode(errorCode)
             .putHeader("content-type", "application/json; charset=utf-8"))
             .end(result.encodePrettily());
     }
@@ -146,15 +151,14 @@ private void returnGushici(RoutingContext routingContext, String obj, JsonObject
                             .putHeader("Content-Length", res.result().length() + "")
                             .write(res.result()).end();
                     } else {
-                        returnError(routingContext, res.cause());
+                        routingContext.fail(res.cause());
                     }
                 });
                 break;
             }
             default:
-                returnError(routingContext, new Exception("参数错误"));
+                routingContext.fail(new ReplyException(ReplyFailure.RECIPIENT_FAILURE, 400, "参数错误"));
         }
-
     }
 
     private HttpServerResponse setCommonHeader(HttpServerResponse response) {
@@ -173,56 +177,27 @@ private void log(RoutingContext routingContext) {
 
     /**
      * 根据 uri 获取参数
-     *
-     * @param uri 例如：/shenghuo/buyi.png, /all
-     * @return {format: "png", classes: [shenghuo, buyi]}, {format:"json", classes:[""]}
+     * @param routingContext example: uri: /shenghuo/buyi.png , /all
+     * @return {format: "png", categories: [shenghuo, buyi]}, {format:"json", categories:[""]}
      */
-    private Future<JsonObject> parseURI(String uri) {
+    private Future<JsonObject> parseURI(RoutingContext routingContext) {
         Future<JsonObject> result = Future.future();
-        if (uri.length() > 100) {
-            result.fail(new IllegalArgumentException("参数太长了，别玩了"));
-            return result;
-        }
-
-        JsonObject pathParams = new JsonObject();
-
-        String rawClasses;
-        String rawFormat = "";
-
-        if (uri.contains(".")) {
-            Pattern pattern = Pattern.compile("/(.*)\\.(.*)");
-            Matcher m = pattern.matcher(uri);
-            if (!m.find()) {
-                result.fail(new IllegalArgumentException("非法参数"));
-                return result;
-            }
-            rawClasses = m.group(1);
-            rawFormat = m.group(2);
-        } else {
-            rawClasses = uri.replaceFirst("/", "");
-        }
-
-
-        String[] classes = rawClasses.split("/");
-        if (classes.length < 1) {
-            result.fail(new IllegalArgumentException("非法参数"));
-            return result;
-        }
-        classes[0] = classes[0].replaceFirst("all", "");
-        pathParams.put("classes", new JsonArray(Arrays.asList(classes)));
 
-        // 处理文件后缀
+        String rawCategory = routingContext.request().getParam("param0");
+        String rawFormat = routingContext.request().getParam("param1");
+        // 如果是 "all" 则当没有分类处理
+        JsonArray categories = new JsonArray(
+                Arrays.stream(rawCategory.split("/"))
+                .filter(s -> !s.isEmpty())
+                .filter(s -> !"all".equals(s))
+                .collect(Collectors.toList()));
+        // 默认 json
+        String format = "".equals(rawFormat) ? "json" : rawFormat;
 
-        String format;
-        if (Arrays.asList("json", "svg", "txt", "png", "").contains(rawFormat)) {
-            format = "".equals(rawFormat) ? "json" : rawFormat;
-        } else {
-            result.fail(new IllegalArgumentException("非法参数"));
-            return result;
-        }
+        JsonObject pathParams = new JsonObject();
+        pathParams.put("categories", categories);
         pathParams.put("format", format);
-
         result.complete(pathParams);
         return result;
     }
-}
+}

src/main/java/ma/luan/yiyan/service/DataService.java

@@ -4,11 +4,14 @@
 import io.vertx.core.CompositeFuture;
 import io.vertx.core.Future;
 import io.vertx.core.eventbus.Message;
+import io.vertx.core.eventbus.ReplyException;
+import io.vertx.core.eventbus.ReplyFailure;
 import io.vertx.core.json.JsonArray;
 import io.vertx.core.json.JsonObject;
 import io.vertx.redis.RedisClient;
 import io.vertx.redis.RedisOptions;
 import ma.luan.yiyan.constants.Key;
+import ma.luan.yiyan.util.CategoryTrie;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 
@@ -21,7 +24,7 @@ public class DataService extends AbstractVerticle {
     private Random random = new Random();
     private RedisOptions redisOptions;
     private Logger log = LogManager.getLogger(this.getClass());
-    private static List<String> keysInRedis;
+    private static CategoryTrie keysInRedis = new CategoryTrie();
 
     public DataService(RedisOptions redisOptions) {
         this.redisOptions = redisOptions;
@@ -37,12 +40,12 @@ public void start(Future<Void> startFuture) {
         Future<JsonArray> jsonKeys = Future.future(f -> redisClient.keys(Key.JSON, f));
         CompositeFuture.all(Arrays.asList(imgKeys, jsonKeys)).setHandler(v -> {
             if (v.succeeded()) {
-                keysInRedis = imgKeys.result().addAll(jsonKeys.result()).stream()
-                    .filter(String.class::isInstance)
-                    .map(String.class::cast)
-                    .collect(Collectors.toList());
+                imgKeys.result().addAll(jsonKeys.result())
+                        .stream()
+                        .forEach(key -> keysInRedis.insert((String) key));
                 startFuture.complete();
             } else {
+                log.error(v.cause());
                 startFuture.fail(v.cause());
             }
         });
@@ -66,46 +69,51 @@ private void getHelpFromRedis(Message message) {
                 );
                 message.reply(newArray);
             } else {
-                message.reply(res.cause());
+                log.error(res.cause());
+                message.fail(500, res.cause().getMessage());
             }
         });
     }
 
+    /**
+     * @param message example: {format: "png", categories: [shenghuo, buyi]}
+     */
     private void getGushiciFromRedis(Message<JsonObject> message) {
-        String keyName = message.body().getJsonArray("classes").stream()
-            .filter(String.class::isInstance)
-            .map(String.class::cast)
-            .collect(Collectors.joining(":"));
-        keyName = ("png".equals(message.body().getString("format")) ? "img" : "json") + ":" + keyName;
-
-        checkAndGetKey(keyName)
+        JsonArray realCategory = new JsonArray()
+                .add("png".equals(message.body().getString("format")) ? "img" : "json")
+                .addAll(message.body().getJsonArray("categories"));
+        checkAndGetKey(realCategory)
             .compose(key -> Future.<String>future(s -> redisClient.srandmember(key, s))) // 从 set 随机返回一个对象
             .setHandler(res -> {
                 if (res.succeeded()) {
                     message.reply(res.result());
                 } else {
-                    message.fail(404, res.cause().getMessage());
+                    if (res.cause() instanceof ReplyException) {
+                        ReplyException exception = (ReplyException) res.cause();
+                        message.fail(exception.failureCode(), exception.getMessage());
+                    }
+                    message.fail(500, res.cause().getMessage());
                 }
             });
     }
 
     /**
-     * @param keys 用户请求的类别
+     * @param categories 用户请求的类别 [img, shenghuo ,buyi]
      * @return 返回一个随机类别的 key （set)
      */
-    private Future<String> checkAndGetKey(String keys) {
+    private Future<String> checkAndGetKey(JsonArray categories) {
         Future<String> result = Future.future();
-        // 这里可以改用多级 Map 减少随机选择范围，不过创建 Map 也要一些开销
-        List<String> toRandom = keysInRedis.stream()
-            .filter(key -> key.startsWith(keys))
-            .collect(Collectors.toList());
+        List<String> categoryList = categories.stream()
+                .filter(String.class::isInstance)
+                .map(String.class::cast)
+                .collect(Collectors.toList());
+        List<String> toRandom = keysInRedis.getKeys(categoryList);
         if (toRandom.size() >= 1) {
             result.complete(toRandom.get(random.nextInt(toRandom.size())));
         } else {
-            result.fail("404, 没有结果，请检查API");
+            result.fail(new ReplyException(ReplyFailure.RECIPIENT_FAILURE, 404, "没有结果，请检查API"));
         }
         return result;
-
     }
 }
 

src/main/java/ma/luan/yiyan/service/LogService.java

@@ -66,6 +66,7 @@ private void getHistoryFromRedis(Message<JsonObject> message) {
                 message.reply(result);
             } else {
                 log.error(v.cause());
+                message.fail(500, v.cause().getMessage());
             }
         });
     }