issue #138 : add ability to load multiple rules at once

easy-rules-mvel/src/main/java/org/jeasy/rules/mvel/MVELRuleDefinitionReader.java

@@ -31,6 +31,7 @@ import java.io.FileNotFoundException;
 import java.io.Reader;
 import java.io.FileReader;
 import java.io.StringReader;
+import java.util.ArrayList;
 import java.util.List;
 import java.util.Map;
 
@@ -53,6 +54,16 @@ class MVELRuleDefinitionReader {
         return createRuleDefinitionFrom(map);
     }
 
+    List<MVELRuleDefinition> readAll(Reader reader) {
+        List<MVELRuleDefinition> ruleDefinitions = new ArrayList<>();
+        Iterable<Object> rules = yaml.loadAll(reader);
+        for (Object rule : rules) {
+            Map<String, Object> map = (Map<String, Object>) rule;
+            ruleDefinitions.add(createRuleDefinitionFrom(map));
+        }
+        return ruleDefinitions;
+    }
+
     private static MVELRuleDefinition createRuleDefinitionFrom(Map<String, Object> map) {
         MVELRuleDefinition ruleDefinition = new MVELRuleDefinition();
 

easy-rules-mvel/src/main/java/org/jeasy/rules/mvel/MVELRuleFactory.java

@@ -23,10 +23,13 @@
  */
 package org.jeasy.rules.mvel;
 
+import org.jeasy.rules.api.Rules;
+
 import java.io.File;
 import java.io.FileNotFoundException;
 import java.io.IOException;
 import java.io.Reader;
+import java.util.List;
 
 /**
  * Factory to create {@link MVELRule} instances.
@@ -68,4 +71,20 @@ public class MVELRuleFactory {
         MVELRuleDefinition ruleDefinition = reader.read(ruleDescriptor.toString());
         return ruleDefinition.create();
     }
+
+    /**
+     * Create a set of {@link MVELRule} from a Reader.
+     *
+     * @param rulesDescriptorReader as a Reader
+     * @return a set of rules
+     * @throws IOException if the I/O operation failed
+     */
+    public static Rules createRulesFrom(Reader rulesDescriptorReader) throws IOException {
+        Rules rules = new Rules();
+        List<MVELRuleDefinition> ruleDefinition = reader.readAll(rulesDescriptorReader);
+        for (MVELRuleDefinition mvelRuleDefinition : ruleDefinition) {
+            rules.register(mvelRuleDefinition.create());
+        }
+        return rules;
+    }
 }

easy-rules-mvel/src/test/java/org/jeasy/rules/mvel/MVELRuleDefinitionReaderTest.java

@@ -27,9 +27,11 @@ import org.jeasy.rules.api.Rule;
 import org.junit.Test;
 
 import java.io.File;
+import java.io.FileReader;
 import java.nio.file.Files;
 import java.nio.file.Paths;
 import java.util.Collections;
+import java.util.List;
 
 import static org.assertj.core.api.Assertions.assertThat;
 
@@ -111,4 +113,43 @@ public class MVELRuleDefinitionReaderTest {
         // then
         // expected exception
     }
+
+    @Test
+    public void testRulesDefinitionReading() throws Exception {
+        // given
+        File rulesDescriptor = new File("src/test/resources/rules.yml");
+
+        // when
+        List<MVELRuleDefinition> ruleDefinitions = ruleDefinitionReader.readAll(new FileReader(rulesDescriptor));
+
+        // then
+        assertThat(ruleDefinitions).hasSize(2);
+        MVELRuleDefinition ruleDefinition = ruleDefinitions.get(0);
+        assertThat(ruleDefinition).isNotNull();
+        assertThat(ruleDefinition.getName()).isEqualTo("adult rule");
+        assertThat(ruleDefinition.getDescription()).isEqualTo("when age is greater then 18, then mark as adult");
+        assertThat(ruleDefinition.getPriority()).isEqualTo(1);
+        assertThat(ruleDefinition.getCondition()).isEqualTo("person.age > 18");
+        assertThat(ruleDefinition.getActions()).isEqualTo(Collections.singletonList("person.setAdult(true);"));
+
+        ruleDefinition = ruleDefinitions.get(1);
+        assertThat(ruleDefinition).isNotNull();
+        assertThat(ruleDefinition.getName()).isEqualTo("weather rule");
+        assertThat(ruleDefinition.getDescription()).isEqualTo("when it rains, then take an umbrella");
+        assertThat(ruleDefinition.getPriority()).isEqualTo(2);
+        assertThat(ruleDefinition.getCondition()).isEqualTo("rain == true");
+        assertThat(ruleDefinition.getActions()).isEqualTo(Collections.singletonList("System.out.println(\"It rains, take an umbrella!\");"));
+    }
+
+    @Test
+    public void testEmptyRulesDefinitionReading() throws Exception {
+        // given
+        File rulesDescriptor = new File("src/test/resources/rules-empty.yml");
+
+        // when
+        List<MVELRuleDefinition> ruleDefinitions = ruleDefinitionReader.readAll(new FileReader(rulesDescriptor));
+
+        // then
+        assertThat(ruleDefinitions).hasSize(0);
+    }
 }

easy-rules-mvel/src/test/java/org/jeasy/rules/mvel/MVELRuleFactoryTest.java

@@ -23,6 +23,8 @@
  */
 package org.jeasy.rules.mvel;
 
+import org.jeasy.rules.api.Rule;
+import org.jeasy.rules.api.Rules;
 import org.junit.Test;
 
 import java.io.File;
@@ -31,6 +33,7 @@ import java.io.Reader;
 import java.io.StringReader;
 import java.nio.file.Files;
 import java.nio.file.Paths;
+import java.util.Iterator;
 
 import static org.assertj.core.api.Assertions.assertThat;
 
@@ -50,6 +53,31 @@ public class MVELRuleFactoryTest {
         assertThat(adultRule.getPriority()).isEqualTo(1);
     }
 
+    @Test
+    public void testRulesCreation() throws Exception {
+        // given
+        File rulesDescriptor = new File("src/test/resources/rules.yml");
+
+        // when
+        Rules rules = MVELRuleFactory.createRulesFrom(new FileReader(rulesDescriptor));
+
+        // then
+        assertThat(rules).hasSize(2);
+        Iterator<Rule> iterator = rules.iterator();
+
+        Rule rule = iterator.next();
+        assertThat(rule).isNotNull();
+        assertThat(rule.getName()).isEqualTo("adult rule");
+        assertThat(rule.getDescription()).isEqualTo("when age is greater then 18, then mark as adult");
+        assertThat(rule.getPriority()).isEqualTo(1);
+
+        rule = iterator.next();
+        assertThat(rule).isNotNull();
+        assertThat(rule.getName()).isEqualTo("weather rule");
+        assertThat(rule.getDescription()).isEqualTo("when it rains, then take an umbrella");
+        assertThat(rule.getPriority()).isEqualTo(2);
+    }
+
     @Test
     public void testRuleCreationFromFileReader() throws Exception{
         // given

easy-rules-mvel/src/test/resources/rules.yml

@@ -0,0 +1,14 @@
+---
+name: adult rule
+description: when age is greater then 18, then mark as adult
+priority: 1
+condition: "person.age > 18"
+actions:
+  - "person.setAdult(true);"
+---
+name: weather rule
+description: when it rains, then take an umbrella
+priority: 2
+condition: "rain == true"
+actions:
+  - "System.out.println(\"It rains, take an umbrella!\");"