1 files changed, 172 insertions, 0 deletions
diff --git a/src/ri-engine/src/main/java/io/trygvis/rules/engine/Engine.java b/src/ri-engine/src/main/java/io/trygvis/rules/engine/Engine.java
new file mode 100644
index 0000000..f2247d3
--- /dev/null
+++ b/src/ri-engine/src/main/java/io/trygvis/rules/engine/Engine.java
@@ -0,0 +1,172 @@
+package io.trygvis.rules.engine;
+
+import org.drools.core.audit.WorkingMemoryConsoleLogger;
+import org.drools.core.base.MapGlobalResolver;
+import org.drools.reflective.classloader.ProjectClassLoader;
+import org.kie.api.KieServices;
+import org.kie.api.event.rule.AgendaEventListener;
+import org.kie.api.event.rule.RuleRuntimeEventListener;
+import org.kie.api.io.Resource;
+import org.kie.api.runtime.KieContainer;
+import org.kie.api.runtime.KieSession;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import javax.annotation.Nullable;
+import java.io.Closeable;
+import java.io.File;
+import java.io.FileNotFoundException;
+import java.io.IOException;
+import java.net.URL;
+import java.net.URLClassLoader;
+import java.nio.charset.StandardCharsets;
+import java.util.ArrayList;
+import java.util.List;
+
+public class Engine implements Closeable {
+    @SuppressWarnings("FieldCanBeLocal")
+    private final Logger logger = LoggerFactory.getLogger(getClass());
+
+    public final String name;
+    @Nullable
+    public final File output;
+    public final DbIo io;
+    public final KieSession session;
+
+    public Engine(String name, File[] databases, @Nullable File output, String[] agendaGroups, File[] modules)
+            throws IOException {
+        this.name = name;
+        this.output = output;
+
+        logger.info("Getting KieServices");
+
+        var services = KieServices.Factory.get();
+
+        var kieRepository = services.getRepository();
+
+        KieContainer container;
+        TemplateLoader templateLoader;
+        if (modules != null && modules.length > 0) {
+            List<Resource> resources = new ArrayList<>();
+            List<URL> files = new ArrayList<>();
+            for (File path : modules) {
+                if (!path.exists()) {
+                    logger.warn("Module path does not exist: {}", path.getAbsolutePath());
+                    continue;
+                }
+
+                logger.info("New KieBuilder: {}, file={}, directory={}", path, path.isFile(), path.isDirectory());
+
+                if (path.isFile()) {
+                    files.add(path.toURI().toURL());
+                }
+
+                var resource = services.getResources().newFileSystemResource(path);
+                logger.info("resource.getResourceType() = {}", resource.getResourceType());
+                resources.add(resource);
+            }
+
+            var module = kieRepository.addKieModule(resources.get(0), resources.subList(1, resources.size()).toArray(new Resource[0]));
+            logger.info("module.getReleaseId() = {}", module.getReleaseId());
+            var rId = module.getReleaseId();
+
+            logger.info("Creating classpath container, releaseId=" + rId);
+            container = services.newKieContainer(rId);
+
+            templateLoader = new ClasspathTemplateLoader(new URLClassLoader(files.toArray(new URL[0])));
+        } else {
+            var classLoader = ProjectClassLoader.findParentClassLoader();
+            container = services.getKieClasspathContainer(classLoader);
+            templateLoader = new ClasspathTemplateLoader(classLoader);
+        }
+
+        logger.info("Creating KieBase \"{}\"", name);
+        logger.info("Available kie base names: {}", container.getKieBaseNames());
+        var kieBase = container.getKieBase(name);
+
+        session = container.newKieSession(name);
+
+        var l = new WorkingMemoryConsoleLogger(session);
+        session.addEventListener((AgendaEventListener) l);
+        session.addEventListener((RuleRuntimeEventListener) l);
+
+        session.getGlobals().setDelegate(new EngineGlobalResolver(templateLoader));
+
+        logger.info("Loading data");
+        io = new DbIo(container, kieBase);
+
+        List<Object> allObjects = new ArrayList<>();
+        for (File database : databases) {
+            var objects = io.load(database);
+
+            if (objects.isEmpty()) {
+                logger.warn("Did not load any objects, something is wrong");
+                return;
+            }
+
+            logger.info("Loaded {} objects from {}", objects.size(), database);
+            allObjects.addAll(objects);
+        }
+        logger.info("Loaded {} objects", allObjects.size());
+
+        for (var object : allObjects) {
+            logger.info("object = " + object);
+            session.insert(object);
+        }
+
+        for (var agendaGroup : agendaGroups) {
+            logger.info("Setting agenda: " + agendaGroup);
+            session.getAgenda().getAgendaGroup(agendaGroup).setFocus();
+            session.fireAllRules();
+        }
+    }
+
+    @Override
+    public void close() {
+        session.dispose();
+    }
+
+    private static class ClasspathTemplateLoader implements TemplateLoader {
+        private final ClassLoader classLoader;
+
+        private ClasspathTemplateLoader(ClassLoader classLoader) {
+            this.classLoader = classLoader;
+        }
+
+        @Override
+        public String load(String name) throws IOException {
+            var resource = "templates/" + name + ".j2";
+
+            try (var inputStream = classLoader.getResourceAsStream(resource)) {
+                if (inputStream == null) {
+                    throw new FileNotFoundException("Classpath resource: " + resource);
+                }
+
+                return new String(inputStream.readAllBytes(), StandardCharsets.UTF_8);
+            }
+        }
+    }
+
+    private class EngineGlobalResolver extends MapGlobalResolver {
+        private final TemplateLoader templateLoader;
+
+        public EngineGlobalResolver() {
+            templateLoader = null;
+        }
+
+        public EngineGlobalResolver(TemplateLoader templateLoader) {
+            this.templateLoader = templateLoader;
+        }
+
+        @Override
+        public Object resolveGlobal(String identifier) {
+            if ("te".equals(identifier)) {
+                if (output == null) {
+                    throw new IllegalArgumentException("An instance of the TemplateEngine is required, but this job is not configured with a output directory.");
+                }
+                return new JinjavaTemplateEngine(templateLoader, output);
+            }
+            return super.resolveGlobal(identifier);
+        }
+    }
+}