MP Config fixes

bom/pom.xml

@@ -248,6 +248,11 @@
                 <artifactId>helidon-config-object-mapping</artifactId>
                 <version>${helidon.version}</version>
             </dependency>
+            <dependency>
+                <groupId>io.helidon.config</groupId>
+                <artifactId>helidon-config-mp</artifactId>
+                <version>${helidon.version}</version>
+            </dependency>
             <!-- security -->
             <dependency>
                 <groupId>io.helidon.security</groupId>

common/metrics/pom.xml

@@ -39,14 +39,7 @@
         <dependency>
             <groupId>org.eclipse.microprofile.metrics</groupId>
             <artifactId>microprofile-metrics-api</artifactId>
-            <version>${version.lib.microprofile-metrics-api}</version>
             <scope>provided</scope>
-            <exclusions>
-                <exclusion>
-                    <groupId>org.osgi</groupId>
-                    <artifactId>org.osgi.annotation.versioning</artifactId>
-                </exclusion>
-            </exclusions>
         </dependency>
     </dependencies>
 </project>

common/service-loader/src/main/java/io/helidon/common/serviceloader/Priorities.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2019, 2020 Oracle and/or its affiliates.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -89,12 +89,26 @@ public static void sort(List<? extends Prioritized> list) {
      * @param defaultPriority default priority for elements that do not have it
      */
     public static void sort(List<?> list, int defaultPriority) {
-        list.sort(Comparator.comparingInt(it -> {
+        list.sort(priorityComparator(defaultPriority));
+    }
+
+    /**
+     * Returns a comparator for two objects, the classes for which are implementations of
+     * {@link io.helidon.common.Prioritized}, and/or optionally annotated with {@link javax.annotation.Priority}
+     * and which applies a specified default priority if either or both classes lack the annotation.
+     *
+     * @param <S> type of object being compared
+     * @param defaultPriority used if the classes for either or both objects
+     * lack the {@code Priority} annotation
+     * @return comparator
+     */
+    public static <S> Comparator<S> priorityComparator(int defaultPriority) {
+        return Comparator.comparingInt(it -> {
             if (it instanceof Class) {
                 return find((Class<?>) it, defaultPriority);
             } else {
                 return find(it, defaultPriority);
             }
-        }));
+        });
     }
 }

common/service-loader/src/test/java/io/helidon/common/serviceloader/PrioritiesTest.java

@@ -0,0 +1,126 @@
+/*
+ * Copyright (c) 2020 Oracle and/or its affiliates.
+ *
+ * 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.helidon.common.serviceloader;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import javax.annotation.Priority;
+
+import io.helidon.common.Prioritized;
+
+import org.junit.jupiter.api.Test;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.hamcrest.MatcherAssert.assertThat;
+
+public class PrioritiesTest {
+    @Test
+    void testSort() {
+        List<Service> services = new ArrayList<>(5);
+        services.add(new DefaultPriority());
+        services.add(new VeryLowPriority());
+        services.add(new LowestPriority());
+        services.add(new HigherPriority());
+        services.add(new LowerPriority());
+
+        Priorities.sort(services, 100);
+
+        validate(services);
+    }
+
+    @Test
+    void testComparator() {
+        List<Service> services = new ArrayList<>(5);
+        // intentionally different order than in other methods, to make sure it is not working "by accident"
+        services.add(new LowestPriority());
+        services.add(new LowerPriority());
+        services.add(new VeryLowPriority());
+        services.add(new HigherPriority());
+        services.add(new DefaultPriority());
+
+        services.sort(Priorities.priorityComparator(100));
+
+        validate(services);
+    }
+
+    private void validate(List<Service> services) {
+        assertThat("There must be 5 services in the list", services.size(), is(5));
+        assertThat(services.get(0).getIt(), is(HigherPriority.IT));
+        assertThat(services.get(1).getIt(), is(LowerPriority.IT));
+        assertThat(services.get(2).getIt(), is(DefaultPriority.IT));
+        assertThat(services.get(3).getIt(), is(VeryLowPriority.IT));
+        assertThat(services.get(4).getIt(), is(LowestPriority.IT));
+    }
+
+    private interface Service {
+        String getIt();
+    }
+
+    @Priority(1)
+    private static class HigherPriority implements Service {
+        private static final String IT = "higher";
+
+        @Override
+        public String getIt() {
+            return IT;
+        }
+    }
+
+    @Priority(2)
+    private static class LowerPriority implements Service {
+        private static final String IT = "lower";
+
+        @Override
+        public String getIt() {
+            return IT;
+        }
+    }
+
+    private static class DefaultPriority implements Service {
+        private static final String IT = "default";
+
+        @Override
+        public String getIt() {
+            return IT;
+        }
+    }
+
+    @Priority(101)
+    private static class VeryLowPriority implements Service {
+        private static final String IT = "veryLow";
+
+        @Override
+        public String getIt() {
+            return IT;
+        }
+    }
+
+    private static class LowestPriority implements Service, Prioritized {
+        private static final String IT = "lowest";
+
+        @Override
+        public String getIt() {
+            return IT;
+        }
+
+        @Override
+        public int priority() {
+            return 1000;
+        }
+    }
+}

config/tests/test-mp-reference/pom.xml → config/config-mp/pom.xml

@@ -16,33 +16,40 @@
   -->
 
 <project xmlns="http://maven.apache.org/POM/4.0.0"
-         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+        xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
     <modelVersion>4.0.0</modelVersion>
     <parent>
-        <groupId>io.helidon.config.tests</groupId>
-        <artifactId>helidon-config-tests-project</artifactId>
+        <groupId>io.helidon.config</groupId>
+        <artifactId>helidon-config-project</artifactId>
         <version>2.0.0-SNAPSHOT</version>
     </parent>
 
-    <artifactId>helidon-config-test-mp-reference</artifactId>
-    <name>Helidon Config Tests MP Reference</name>
-
-    <description>
-        Integration tests of reference in MP
-    </description>
+    <artifactId>helidon-config-mp</artifactId>
+    <name>Helidon Config MP</name>
+    <description>Core of the implementation of MicroProfile Config specification</description>
 
     <dependencies>
         <dependency>
-            <groupId>org.eclipse.microprofile.config</groupId>
-            <artifactId>microprofile-config-api</artifactId>
+            <groupId>jakarta.annotation</groupId>
+            <artifactId>jakarta.annotation-api</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>io.helidon.common</groupId>
+            <artifactId>helidon-common</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>io.helidon.common</groupId>
+            <artifactId>helidon-common-service-loader</artifactId>
         </dependency>
         <dependency>
             <groupId>io.helidon.config</groupId>
             <artifactId>helidon-config</artifactId>
-            <scope>runtime</scope>
         </dependency>
-
+        <dependency>
+            <groupId>org.eclipse.microprofile.config</groupId>
+            <artifactId>microprofile-config-api</artifactId>
+        </dependency>
         <dependency>
             <groupId>org.junit.jupiter</groupId>
             <artifactId>junit-jupiter-api</artifactId>

config/config-mp/src/main/java/io/helidon/config/mp/MpConfig.java

@@ -0,0 +1,80 @@
+/*
+ * Copyright (c) 2020 Oracle and/or its affiliates.
+ *
+ * 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.helidon.config.mp;
+
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Optional;
+
+import io.helidon.config.ConfigSources;
+
+import org.eclipse.microprofile.config.Config;
+
+/**
+ * Utilities for Helidon MicroProfile Config implementation.
+ */
+public final class MpConfig {
+    private MpConfig() {
+    }
+
+    /**
+     * This method allows use to use Helidon Config on top of an MP config.
+     * There is a limitation - the converters configured with MP config will not be available, unless
+     * the implementation is coming from Helidon.
+     * <p>
+     * If you want to use the Helidon {@link io.helidon.config.Config} API instead of the MicroProfile
+     * {@link org.eclipse.microprofile.config.Config} one, this method will create a Helidon config
+     * instance that is based on the provided configuration instance.
+     *
+     * @param mpConfig MP Config instance
+     * @return a new Helidon config using only the mpConfig as its config source
+     */
+    @SuppressWarnings("unchecked")
+    public static io.helidon.config.Config toHelidonConfig(Config mpConfig) {
+        if (mpConfig instanceof io.helidon.config.Config) {
+            return (io.helidon.config.Config) mpConfig;
+        }
+
+        io.helidon.config.Config.Builder builder = io.helidon.config.Config.builder()
+                .disableEnvironmentVariablesSource()
+                .disableSystemPropertiesSource()
+                .disableMapperServices()
+                .disableCaching()
+                .disableParserServices()
+                .disableFilterServices();
+
+        if (mpConfig instanceof MpConfigImpl) {
+            ((MpConfigImpl) mpConfig).converters()
+                    .forEach((clazz, converter) -> {
+                        Class<Object> cl = (Class<Object>) clazz;
+                        builder.addStringMapper(cl, converter::convert);
+                    });
+        }
+
+        Map<String, String> allConfig = new HashMap<>();
+        mpConfig.getPropertyNames()
+                .forEach(it -> {
+                    // covering the condition where a config key disappears between getting the property names and requesting
+                    // the value
+                    Optional<String> optionalValue = mpConfig.getOptionalValue(it, String.class);
+                    optionalValue.ifPresent(value -> allConfig.put(it, value));
+                });
+
+        return builder.addSource(ConfigSources.create(allConfig))
+                .build();
+    }
+}