optimize: add saga statelang semantic validation (#5928)

changes/en-us/2.0.0.md

@@ -80,6 +80,7 @@ The version is updated as follows:
 - [[#5930](https://github.com/seata/seata/pull/5930)] fix the issue of missing sentinel password in store redis mode
 
 ### optimize：
+- [[#5928](https://github.com/seata/seata/pull/5928)] add Saga statelang semantic validation
 - [[#5208](https://github.com/seata/seata/pull/5208)] optimize throwable getCause once more
 - [[#5212](https://github.com/seata/seata/pull/5212)] optimize log message level
 - [[#5237](https://github.com/seata/seata/pull/5237)] optimize exception log message print(EnhancedServiceLoader.loadFile#cahtch)

changes/zh-cn/2.0.0.md

@@ -79,6 +79,7 @@ Seata 是一款开源的分布式事务解决方案，提供高性能和简单
 - [[#5930](https://github.com/seata/seata/pull/5930)] 修复存储为redis哨兵模式下哨兵密码缺失的问题
 
 ### optimize：
+- [[#5928](https://github.com/seata/seata/pull/5928)] 增加Saga模式状态机语义验证阶段
 - [[#5208](https://github.com/seata/seata/pull/5208)] 优化多次重复获取Throwable#getCause问题
 - [[#5212](https://github.com/seata/seata/pull/5212)] 优化不合理的日志信息级别
 - [[#5237](https://github.com/seata/seata/pull/5237)] 优化异常日志打印(EnhancedServiceLoader.loadFile#cahtch)

saga/seata-saga-statelang/src/main/java/io/seata/saga/statelang/parser/impl/StateMachineParserImpl.java

@@ -30,6 +30,7 @@
 import io.seata.saga.statelang.parser.StateParser;
 import io.seata.saga.statelang.parser.StateParserFactory;
 import io.seata.saga.statelang.parser.utils.DesignerJsonTransformer;
+import io.seata.saga.statelang.validator.StateMachineValidator;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -44,6 +45,8 @@ public class StateMachineParserImpl implements StateMachineParser {
 
     private String jsonParserName = DomainConstants.DEFAULT_JSON_PARSER;
 
+    private final StateMachineValidator validator = new StateMachineValidator();
+
     public StateMachineParserImpl(String jsonParserName) {
         if (StringUtils.isNotBlank(jsonParserName)) {
             this.jsonParserName = jsonParserName;
@@ -124,6 +127,8 @@ public StateMachine parse(String json) {
                 }
             }
         }
+
+        validator.validate(stateMachine);
         return stateMachine;
     }
 
@@ -134,4 +139,4 @@ public String getJsonParserName() {
     public void setJsonParserName(String jsonParserName) {
         this.jsonParserName = jsonParserName;
     }
-}
+}

saga/seata-saga-statelang/src/main/java/io/seata/saga/statelang/parser/utils/StateMachineUtils.java

@@ -0,0 +1,62 @@
+/*
+ *  Copyright 1999-2019 Seata.io Group.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *       http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package io.seata.saga.statelang.parser.utils;
+
+import io.seata.common.util.StringUtils;
+import io.seata.saga.statelang.domain.ChoiceState;
+import io.seata.saga.statelang.domain.DomainConstants;
+import io.seata.saga.statelang.domain.State;
+import io.seata.saga.statelang.domain.TaskState;
+
+import java.util.HashSet;
+import java.util.Optional;
+import java.util.Set;
+import java.util.stream.Collectors;
+
+/**
+ * Util class for parsing StateMachine
+ *
+ * @author ptyin
+ */
+public class StateMachineUtils {
+    public static Set<String> getAllPossibleSubsequentStates(State state) {
+        Set<String> subsequentStates = new HashSet<>();
+        // Next state
+        subsequentStates.add(state.getNext());
+        switch (state.getType()) {
+            case DomainConstants.STATE_TYPE_SCRIPT_TASK:
+            case DomainConstants.STATE_TYPE_SERVICE_TASK:
+            case DomainConstants.STATE_TYPE_SUB_STATE_MACHINE:
+            case DomainConstants.STATE_TYPE_SUB_MACHINE_COMPENSATION:
+                // Next state in catches
+                Optional.ofNullable(((TaskState) state).getCatches())
+                        .ifPresent(c -> c.forEach(e -> subsequentStates.add(e.getNext())));
+                break;
+
+            case DomainConstants.STATE_TYPE_CHOICE:
+                // Choice state
+                Optional.ofNullable(((ChoiceState) state).getChoices())
+                        .ifPresent(c -> c.forEach(e -> subsequentStates.add(e.getNext())));
+                // Default choice
+                subsequentStates.add(((ChoiceState) state).getDefault());
+                break;
+            default:
+                // Otherwise do nothing
+        }
+        return subsequentStates.stream().filter(StringUtils::isNotBlank).collect(Collectors.toSet());
+    }
+}

saga/seata-saga-statelang/src/main/java/io/seata/saga/statelang/validator/Rule.java

@@ -0,0 +1,48 @@
+/*
+ *  Copyright 1999-2019 Seata.io Group.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *       http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package io.seata.saga.statelang.validator;
+
+import io.seata.saga.statelang.domain.StateMachine;
+
+/**
+ * Validation rule interface, use SPI to inject rules
+ *
+ * @author ptyin
+ */
+public interface Rule {
+    /**
+     * Validate a state machine
+     *
+     * @param stateMachine state machine
+     * @return true if passes, false if fails
+     */
+    boolean validate(StateMachine stateMachine);
+
+    /**
+     * Get the rule name
+     *
+     * @return name of the rule
+     */
+    String getName();
+
+    /**
+     * Get hints why validation passes or fails. Use this method to show more messages about validation result.
+     *
+     * @return hint of the rule
+     */
+    String getHint();
+}

saga/seata-saga-statelang/src/main/java/io/seata/saga/statelang/validator/RuleFactory.java

@@ -0,0 +1,34 @@
+/*
+ *  Copyright 1999-2019 Seata.io Group.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *       http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package io.seata.saga.statelang.validator;
+
+import io.seata.common.loader.EnhancedServiceLoader;
+
+import java.util.List;
+
+/**
+ * Factorial class to get all rules.
+ *
+ * @author ptyin
+ */
+public class RuleFactory {
+    private static final List<Rule> RULES = EnhancedServiceLoader.loadAll(Rule.class);
+
+    public static List<Rule> getRules() {
+        return RULES;
+    }
+}

saga/seata-saga-statelang/src/main/java/io/seata/saga/statelang/validator/StateMachineValidator.java

@@ -0,0 +1,50 @@
+/*
+ *  Copyright 1999-2019 Seata.io Group.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *       http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package io.seata.saga.statelang.validator;
+
+import io.seata.saga.statelang.domain.StateMachine;
+
+import java.util.List;
+
+/**
+ * State machine validator used to validate rules.
+ *
+ * @author ptyin
+ */
+public class StateMachineValidator {
+
+    /**
+     * Validate on state machine
+     *
+     * @param stateMachine state machine
+     * @throws ValidationException throws if there is a validation rule failed
+     */
+    public void validate(StateMachine stateMachine) throws ValidationException {
+        List<Rule> rules = RuleFactory.getRules();
+        for (Rule rule: rules) {
+            boolean pass;
+            try {
+                pass = rule.validate(stateMachine);
+            } catch (Throwable e) {
+                throw new ValidationException(rule, "Exception occurs", e);
+            }
+            if (!pass) {
+                throw new ValidationException(rule, "Failed");
+            }
+        }
+    }
+}

saga/seata-saga-statelang/src/main/java/io/seata/saga/statelang/validator/ValidationException.java

@@ -0,0 +1,43 @@
+/*
+ *  Copyright 1999-2019 Seata.io Group.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *       http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package io.seata.saga.statelang.validator;
+
+import io.seata.common.util.StringUtils;
+
+/**
+ * Validation exception throws if exception occurs in validation phase.
+ *
+ * @author ptyin
+ */
+public class ValidationException extends RuntimeException {
+
+    public ValidationException(Rule rule, String message) {
+        super(spliceMessage(rule, message));
+    }
+
+    public ValidationException(Rule rule, String message, Throwable cause) {
+        super(spliceMessage(rule, message), cause);
+    }
+
+    private static String spliceMessage(Rule rule, String message) {
+        String canonicalMessage = String.format("Rule [%s]: %s", rule.getName(), message);
+        if (StringUtils.isNotBlank(rule.getHint())) {
+            canonicalMessage = canonicalMessage + ", hints: " + rule.getHint();
+        }
+        return canonicalMessage;
+    }
+}

saga/seata-saga-statelang/src/main/java/io/seata/saga/statelang/validator/impl/AbstractRule.java

@@ -0,0 +1,39 @@
+/*
+ *  Copyright 1999-2019 Seata.io Group.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *       http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package io.seata.saga.statelang.validator.impl;
+
+import io.seata.saga.statelang.validator.Rule;
+
+/**
+ * Abstract class for {@link Rule}
+ *
+ * @author ptyin
+ */
+public abstract class AbstractRule implements Rule {
+
+    protected String hint;
+
+    @Override
+    public String getName() {
+        return getClass().getSimpleName();
+    }
+
+    @Override
+    public String getHint() {
+        return hint;
+    }
+}