Break out configuration file read

Break out the reading of the configuration file to a separate class to
prepare for the addition of a REST API to replace the configuration
file.

Change-Id: If61669563d8bc9b0b235a49a30fae3b3efbc5148
Issue-ID: CCSDK-2966
Signed-off-by: elinuxhenrik <henrik.b.andersson@est.tech>

2 files changed, 103 insertions, 38 deletions

diff --git a/a1-policy-management/src/main/java/org/onap/ccsdk/oran/a1policymanagementservice/configuration/ConfigurationFile.java b/a1-policy-management/src/main/java/org/onap/ccsdk/oran/a1policymanagementservice/configuration/ConfigurationFile.java
new file mode 100644
index 00000000..345722cb
--- /dev/null
+++ b/a1-policy-management/src/main/java/org/onap/ccsdk/oran/a1policymanagementservice/configuration/ConfigurationFile.java
@@ -0,0 +1,93 @@
+/*-
+ * ========================LICENSE_START=================================
+ * Copyright (C) 2020 Nordix Foundation. All rights reserved.
+ * ======================================================================
+ * 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.
+ * ========================LICENSE_END===================================
+ */
+
+package org.onap.ccsdk.oran.a1policymanagementservice.configuration;
+
+import com.google.gson.Gson;
+import com.google.gson.JsonElement;
+import com.google.gson.JsonObject;
+import com.google.gson.JsonParser;
+import java.io.BufferedInputStream;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileWriter;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.util.Optional;
+import javax.validation.constraints.NotNull;
+import org.onap.ccsdk.oran.a1policymanagementservice.exceptions.ServiceException;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Component;
+
+@Component
+public class ConfigurationFile {
+    private static final Logger logger = LoggerFactory.getLogger(ConfigurationFile.class);
+
+    final ApplicationConfig appConfig;
+    final Gson gson = new Gson();
+
+    @Autowired
+    public ConfigurationFile(ApplicationConfig appConfig) {
+        this.appConfig = appConfig;
+    }
+
+    public synchronized Optional<JsonObject> readFile() {
+        String filepath = appConfig.getLocalConfigurationFilePath();
+        if (!fileExists(filepath)) {
+            return Optional.empty();
+        }
+
+        try (InputStream inputStream = createInputStream(filepath)) {
+            JsonObject rootObject = getJsonElement(inputStream).getAsJsonObject();
+            logger.debug("Local configuration file loaded: {}", filepath);
+            return Optional.of(rootObject);
+        } catch (Exception e) {
+            logger.error("Local configuration file not loaded: {}, {}", filepath, e.getMessage());
+            return Optional.empty();
+        }
+    }
+
+    public synchronized void writeFile(JsonObject content) throws ServiceException {
+        String filepath = appConfig.getLocalConfigurationFilePath();
+        try (FileWriter fileWriter = getFileWriter(filepath)) {
+            gson.toJson(content, fileWriter);
+        } catch (IOException e) {
+            logger.error("Local configuration file not written: {}, {}", filepath, e.getMessage());
+            throw new ServiceException("Local configuration file not written");
+        }
+    }
+
+    FileWriter getFileWriter(String filepath) throws IOException {
+        return new FileWriter(filepath);
+    }
+
+    private boolean fileExists(String filepath) {
+        return (new File(filepath).exists());
+    }
+
+    private JsonElement getJsonElement(InputStream inputStream) {
+        return JsonParser.parseReader(new InputStreamReader(inputStream));
+    }
+
+    private InputStream createInputStream(@NotNull String filepath) throws IOException {
+        return new BufferedInputStream(new FileInputStream(filepath));
+    }
+}
diff --git a/a1-policy-management/src/main/java/org/onap/ccsdk/oran/a1policymanagementservice/tasks/RefreshConfigTask.java b/a1-policy-management/src/main/java/org/onap/ccsdk/oran/a1policymanagementservice/tasks/RefreshConfigTask.java
index e4d7d8d7..b8341240 100644
--- a/a1-policy-management/src/main/java/org/onap/ccsdk/oran/a1policymanagementservice/tasks/RefreshConfigTask.java
+++ b/a1-policy-management/src/main/java/org/onap/ccsdk/oran/a1policymanagementservice/tasks/RefreshConfigTask.java
@@ -20,21 +20,12 @@
 
 package org.onap.ccsdk.oran.a1policymanagementservice.tasks;
 
-import com.google.gson.JsonElement;
 import com.google.gson.JsonObject;
-import com.google.gson.JsonParser;
 
-import java.io.BufferedInputStream;
-import java.io.File;
-import java.io.FileInputStream;
-import java.io.IOException;
-import java.io.InputStream;
-import java.io.InputStreamReader;
 import java.time.Duration;
+import java.util.Optional;
 import java.util.Properties;
 
-import javax.validation.constraints.NotNull;
-
 import lombok.AccessLevel;
 import lombok.Getter;
 
@@ -43,6 +34,7 @@ import org.onap.ccsdk.oran.a1policymanagementservice.clients.AsyncRestClientFact
 import org.onap.ccsdk.oran.a1policymanagementservice.configuration.ApplicationConfig;
 import org.onap.ccsdk.oran.a1policymanagementservice.configuration.ApplicationConfig.RicConfigUpdate;
 import org.onap.ccsdk.oran.a1policymanagementservice.configuration.ApplicationConfigParser;
+import org.onap.ccsdk.oran.a1policymanagementservice.configuration.ConfigurationFile;
 import org.onap.ccsdk.oran.a1policymanagementservice.configuration.RicConfig;
 import org.onap.ccsdk.oran.a1policymanagementservice.repository.Policies;
 import org.onap.ccsdk.oran.a1policymanagementservice.repository.PolicyTypes;
@@ -83,6 +75,7 @@ public class RefreshConfigTask {
      */
     static final Duration CONFIG_REFRESH_INTERVAL = Duration.ofMinutes(1);
 
+    final ConfigurationFile configurationFile;
     final ApplicationConfig appConfig;
     @Getter(AccessLevel.PROTECTED)
     private Disposable refreshTask = null;
@@ -96,8 +89,9 @@ public class RefreshConfigTask {
     private final AsyncRestClientFactory restClientFactory;
 
     @Autowired
-    public RefreshConfigTask(ApplicationConfig appConfig, Rics rics, Policies policies, Services services,
-            PolicyTypes policyTypes, A1ClientFactory a1ClientFactory) {
+    public RefreshConfigTask(ConfigurationFile configurationFile, ApplicationConfig appConfig, Rics rics,
+            Policies policies, Services services, PolicyTypes policyTypes, A1ClientFactory a1ClientFactory) {
+        this.configurationFile = configurationFile;
         this.appConfig = appConfig;
         this.rics = rics;
         this.policies = policies;
@@ -195,10 +189,6 @@ public class RefreshConfigTask {
         return this.appConfig.setConfiguration(config);
     }
 
-    boolean fileExists(String filepath) {
-        return (filepath != null && (new File(filepath).exists()));
-    }
-
     private void removePoliciciesInRic(@Nullable Ric ric) {
         if (ric != null) {
             RicSynchronizationTask synch =
@@ -245,28 +235,10 @@ public class RefreshConfigTask {
      * Reads the configuration from file.
      */
     Flux<JsonObject> loadConfigurationFromFile() {
-        String filepath = appConfig.getLocalConfigurationFilePath();
-        if (!fileExists(filepath)) {
-            return Flux.empty();
-        }
-
-        try (InputStream inputStream = createInputStream(filepath)) {
-            JsonObject rootObject = getJsonElement(inputStream).getAsJsonObject();
-            ApplicationConfigParser appParser = new ApplicationConfigParser();
-            appParser.parse(rootObject);
-            logger.debug("Local configuration file loaded: {}", filepath);
-            return Flux.just(rootObject);
-        } catch (Exception e) {
-            logger.error("Local configuration file not loaded: {}, {}", filepath, e.getMessage());
-            return Flux.empty();
+        Optional<JsonObject> readJson = configurationFile.readFile();
+        if (readJson.isPresent()) {
+            return Flux.just(readJson.get());
         }
-    }
-
-    JsonElement getJsonElement(InputStream inputStream) {
-        return JsonParser.parseReader(new InputStreamReader(inputStream));
-    }
-
-    InputStream createInputStream(@NotNull String filepath) throws IOException {
-        return new BufferedInputStream(new FileInputStream(filepath));
+        return Flux.empty();
     }
 }