implement config source (#17)

* implement config source, configureable with -Dconfig.source=environemnt or -Dconfig.source=properties

* add tests, configuration type instantiation from main

.gitignore

@@ -15,3 +15,6 @@ buildNumber.properties
 .project
 # JDT-specific (Eclipse Java Development Tools)
 .classpath
+.flattened-pom.xml
+.idea/
+aer_01.iml

pom.xml

@@ -325,6 +325,9 @@
         <configuration>
           <parallel>all</parallel>
           <useUnlimitedThreads>true</useUnlimitedThreads>
+          <environmentVariables>
+            <AZURE_NAMESPACE>azure_namespace_from_env</AZURE_NAMESPACE>
+          </environmentVariables>
         </configuration>
       </plugin>
       <plugin>

src/main/java/com/teragrep/aer_01/EventContextConsumer.java

@@ -49,6 +49,7 @@
 import com.codahale.metrics.MetricRegistry;
 import com.teragrep.aer_01.config.RelpConfig;
 import com.teragrep.aer_01.config.SyslogConfig;
+import com.teragrep.aer_01.config.source.Sourceable;
 import com.teragrep.rlo_14.SDElement;
 import com.teragrep.rlo_14.SyslogMessage;
 
@@ -63,8 +64,8 @@ final class EventContextConsumer implements AutoCloseable, Consumer<EventContext
     private final Output output;
     private final String realHostName;
     private final SyslogConfig syslogConfig;
-    EventContextConsumer() {
-        RelpConfig relpConfig = new RelpConfig();
+    EventContextConsumer(Sourceable configSource) {
+        RelpConfig relpConfig = new RelpConfig(configSource);
 
         this.output = new Output(
                 "defaultOutput",
@@ -78,7 +79,7 @@ final class EventContextConsumer implements AutoCloseable, Consumer<EventContext
         );
 
         this.realHostName = getRealHostName();
-        this.syslogConfig = new SyslogConfig();
+        this.syslogConfig = new SyslogConfig(configSource);
     }
 
     private String getRealHostName() {

src/main/java/com/teragrep/aer_01/Main.java

@@ -56,6 +56,9 @@
 import com.azure.storage.blob.BlobContainerAsyncClient;
 import com.azure.storage.blob.BlobContainerClientBuilder;
 import com.teragrep.aer_01.config.AzureConfig;
+import com.teragrep.aer_01.config.source.EnvironmentSource;
+import com.teragrep.aer_01.config.source.PropertySource;
+import com.teragrep.aer_01.config.source.Sourceable;
 
 import java.io.IOException;
 
@@ -64,8 +67,10 @@
 public final class Main {
 
     public static void main(String[] args) throws IOException, InterruptedException {
-        try (final EventContextConsumer PARTITION_PROCESSOR = new EventContextConsumer()) {
-            AzureConfig azureConfig = new AzureConfig();
+        final Sourceable configSource = getConfigSource();
+
+        try (final EventContextConsumer PARTITION_PROCESSOR = new EventContextConsumer(configSource)) {
+            AzureConfig azureConfig = new AzureConfig(configSource);
             final ErrorContextConsumer ERROR_HANDLER = new ErrorContextConsumer();
 
 // create a token using the default Azure credential
@@ -98,4 +103,21 @@ public static void main(String[] args) throws IOException, InterruptedException
             eventProcessorClient.stop();
         }
     }
+
+    private static Sourceable getConfigSource() {
+        String type = System.getProperty("config.source", "properties");
+
+        Sourceable rv;
+        if ("properties".equals(type)) {
+            rv = new PropertySource();
+        }
+        else if ("environment".equals(type)) {
+            rv = new EnvironmentSource();
+        }
+        else {
+            throw new IllegalArgumentException("config.source not within supported types: [properties, environment]");
+        }
+
+        return rv;
+    }
 }

src/main/java/com/teragrep/aer_01/config/AzureConfig.java

@@ -45,31 +45,36 @@
  */
 package com.teragrep.aer_01.config;
 
+import com.teragrep.aer_01.config.source.Sourceable;
+
 final public class AzureConfig {
+    public final Sourceable configSource;
     public final String namespaceName;
     public final String eventHubName;
     public final String blobStorageEndpoint;
     public final String blobStorageContainerName;
-    public AzureConfig() {
+
+    public AzureConfig(Sourceable configSource) {
+        this.configSource = configSource;
         this.namespaceName = getNamespaceName();
         this.eventHubName = getEventHubName();
         this.blobStorageEndpoint = getBlobStorageEndpoint();
         this.blobStorageContainerName = getBlobStorageContainerName();
     }
 
     private String getNamespaceName() {
-        return System.getProperty("azure.namespace", "<NAMESPACE NAME>.servicebus.windows.net");
+        return configSource.source("azure.namespace", "<NAMESPACE NAME>.servicebus.windows.net");
     }
 
     private String getEventHubName() {
-        return System.getProperty("azure.eventhub", "<EVENT HUB NAME>");
+        return configSource.source("azure.eventhub", "<EVENT HUB NAME>");
     }
 
     private String getBlobStorageEndpoint() {
-        return System.getProperty("azure.blobstorage.endpoint", "https://<STORAGE ACCOUNT NAME>.blob.core.windows.net");
+        return configSource.source("azure.blobstorage.endpoint", "https://<STORAGE ACCOUNT NAME>.blob.core.windows.net");
     }
 
     private String getBlobStorageContainerName() {
-        return System.getProperty("azure.blobstorage.container", "<CONTAINER NAME>");
+        return configSource.source("azure.blobstorage.container", "<CONTAINER NAME>");
     }
 }

src/main/java/com/teragrep/aer_01/config/RelpConfig.java

@@ -46,17 +46,20 @@
 package com.teragrep.aer_01.config;
 
 
+import com.teragrep.aer_01.config.source.Sourceable;
+
 // copy from snw_01 with fixes
 final public class RelpConfig {
-
+    public final Sourceable configSource;
     public final int connectionTimeout;
     public final int readTimeout;
     public final int writeTimeout;
     public final int reconnectInterval;
     public final int destinationPort;
     public final String destinationAddress;
 
-    public RelpConfig() {
+    public RelpConfig(Sourceable configSource) {
+        this.configSource = configSource;
         this.connectionTimeout = getConnectTimeout();
         this.readTimeout = getReadTimeout();
         this.writeTimeout = getWriteTimeout();
@@ -69,46 +72,46 @@ public RelpConfig() {
      * @return relp.connection.timeout
      */
     private int getConnectTimeout() {
-        String connectTimeout = System.getProperty("relp.connection.timeout", "5000");
+        String connectTimeout = configSource.source("relp.connection.timeout", "5000");
         return Integer.parseInt(connectTimeout);
     }
 
     /**
      * @return relp.transaction.read.timeout
      */
     private int getReadTimeout() {
-        String readTimeout = System.getProperty("relp.transaction.read.timeout", "5000");
+        String readTimeout = configSource.source("relp.transaction.read.timeout", "5000");
         return Integer.parseInt(readTimeout);
     }
 
     /**
      * @return relp.transaction.write.timeout
      */
     private int getWriteTimeout() {
-        String writeTimeout = System.getProperty("relp.transaction.write.timeout", "5000");
+        String writeTimeout = configSource.source("relp.transaction.write.timeout", "5000");
         return Integer.parseInt(writeTimeout);
     }
 
     /**
      * @return relp.connection.retry.interval
      */
     private int getReconnectInterval() {
-        String reconnectString = System.getProperty("relp.connection.retry.interval", "5000");
+        String reconnectString = configSource.source("relp.connection.retry.interval", "5000");
         return Integer.parseInt(reconnectString);
     }
 
     /**
      * @return relp.connection.port
      */
     private int getRelpPort() {
-        String relpPort = System.getProperty("relp.connection.port", "601");
+        String relpPort = configSource.source("relp.connection.port", "601");
         return Integer.parseInt(relpPort);
     }
 
     /**
      * @return relp.connection.address
      */
     private String getRelpAddress() {
-        return System.getProperty("relp.connection.address", "localhost");
+        return configSource.source("relp.connection.address", "localhost");
     }
 }

src/main/java/com/teragrep/aer_01/config/SyslogConfig.java

@@ -45,29 +45,31 @@
  */
 package com.teragrep.aer_01.config;
 
-final public class SyslogConfig {
-
-    // TODO copy from snw_01
+import com.teragrep.aer_01.config.source.Sourceable;
 
+final public class SyslogConfig {
+    // TODO this is a copy from snw_01, with configSource
+    public final Sourceable configSource;
     public final String hostname;
     public final String appName;
 
-    public SyslogConfig() {
+    public SyslogConfig(Sourceable configSource) {
+        this.configSource = configSource;
         this.hostname = getHostname();
         this.appName = getAppName();
     }
     /**
      * @return syslog.appname
      */
     private String getAppName() {
-        return System.getProperty("syslog.appname","aer-01");
+        return configSource.source("syslog.appname","aer-01");
     }
 
     /**
      * @return syslog.hostname
      */
     private String getHostname() {
-        return System.getProperty("syslog.hostname","localhost.localdomain");
+        return configSource.source("syslog.hostname","localhost.localdomain");
     }
 }
 

src/main/java/com/teragrep/aer_01/config/source/EnvironmentSource.java

@@ -0,0 +1,73 @@
+/*
+ * Teragrep Azure Eventhub Reader
+ * Copyright (C) 2023  Suomen Kanuuna Oy
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://github.com/teragrep/teragrep/blob/main/LICENSE>.
+ *
+ *
+ * Additional permission under GNU Affero General Public License version 3
+ * section 7
+ *
+ * If you modify this Program, or any covered work, by linking or combining it
+ * with other code, such other code is not for that reason alone subject to any
+ * of the requirements of the GNU Affero GPL version 3 as long as this Program
+ * is the same Program as licensed from Suomen Kanuuna Oy without any additional
+ * modifications.
+ *
+ * Supplemented terms under GNU Affero General Public License version 3
+ * section 7
+ *
+ * Origin of the software must be attributed to Suomen Kanuuna Oy. Any modified
+ * versions must be marked as "Modified version of" The Program.
+ *
+ * Names of the licensors and authors may not be used for publicity purposes.
+ *
+ * No rights are granted for use of trade names, trademarks, or service marks
+ * which are in The Program if any.
+ *
+ * Licensee must indemnify licensors and authors for any liability that these
+ * contractual assumptions impose on licensors and authors.
+ *
+ * To the extent this program is licensed as part of the Commercial versions of
+ * Teragrep, the applicable Commercial License may apply to this file if you as
+ * a licensee so wish it.
+ */
+package com.teragrep.aer_01.config.source;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.util.Map;
+
+public class EnvironmentSource implements Sourceable {
+    private static final Logger LOGGER = LoggerFactory.getLogger(EnvironmentSource.class);
+
+    private final Map<String, String> envValues = System.getenv();
+
+    @Override
+    public String source(String name, String defaultValue) {
+        String variable = name.toUpperCase().replace(".", "_");
+        LOGGER.debug("sourcing name <[{}]> as environment variable <[{}]>", name, variable);
+        String rv =  envValues.getOrDefault(variable, defaultValue);
+        LOGGER.debug("sourced value <[{}]> for variable <[{}]>", rv, variable);
+        return rv;
+    }
+
+    @Override
+    public String toString() {
+        return "EnvironmentSource{" +
+                "envValues=" + envValues +
+                '}';
+    }
+}

src/main/java/com/teragrep/aer_01/config/source/PropertySource.java

@@ -0,0 +1,67 @@
+/*
+ * Teragrep Azure Eventhub Reader
+ * Copyright (C) 2023  Suomen Kanuuna Oy
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://github.com/teragrep/teragrep/blob/main/LICENSE>.
+ *
+ *
+ * Additional permission under GNU Affero General Public License version 3
+ * section 7
+ *
+ * If you modify this Program, or any covered work, by linking or combining it
+ * with other code, such other code is not for that reason alone subject to any
+ * of the requirements of the GNU Affero GPL version 3 as long as this Program
+ * is the same Program as licensed from Suomen Kanuuna Oy without any additional
+ * modifications.
+ *
+ * Supplemented terms under GNU Affero General Public License version 3
+ * section 7
+ *
+ * Origin of the software must be attributed to Suomen Kanuuna Oy. Any modified
+ * versions must be marked as "Modified version of" The Program.
+ *
+ * Names of the licensors and authors may not be used for publicity purposes.
+ *
+ * No rights are granted for use of trade names, trademarks, or service marks
+ * which are in The Program if any.
+ *
+ * Licensee must indemnify licensors and authors for any liability that these
+ * contractual assumptions impose on licensors and authors.
+ *
+ * To the extent this program is licensed as part of the Commercial versions of
+ * Teragrep, the applicable Commercial License may apply to this file if you as
+ * a licensee so wish it.
+ */
+package com.teragrep.aer_01.config.source;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.util.Properties;
+
+public final class PropertySource implements Sourceable {
+    private static final Logger LOGGER = LoggerFactory.getLogger(PropertySource.class);
+    private final Properties properties;
+
+    public PropertySource() {
+        this.properties = System.getProperties();
+    }
+    @Override
+    public String source(String name, String defaultValue) {
+        LOGGER.debug("sourcing property name <[{}]>", name);
+        String rv = properties.getProperty(name, defaultValue);
+        LOGGER.debug("sourced value <[{}]> for property name <[{}]>", rv, name);
+        return rv;
+    }
+}