development configuration overriding env

.gitignore

@@ -1 +1,2 @@
-/target/
+/target/
+/src/main/resources/development.properties

README.md

@@ -1,3 +1,15 @@
 # mavor
 
-download a maven artifact and all its dependencies as zip
+download a maven artifact and all its dependencies as zip
+
+## Environment Variables
+all environemnt variables are required
+* `MAVOR_MAVEN_EXECUTABLE`: path to the maven executable, e.g. `/usr/bin/mvn`
+* `MAVOR_TEMP_DIR`: path to a readable and writeable directory to temporarily store files, e.g. `/home/damage/Temp`
+
+## Development
+To avoid setting environment variables during devleopment, create `src/main/resources/development.properties` with content like:
+```
+MAVOR_MAVEN_EXECUTABLE=/usr/bin/mvn
+MAVOR_TEMP_DIR=/home/damage/Temp
+```

src/main/java/de/devloop/mavor/Configuration.java

@@ -1,14 +1,36 @@
 package de.devloop.mavor;
 
+import java.io.IOException;
+import java.io.InputStream;
 import java.util.Objects;
+import java.util.Properties;
 
 public class Configuration {
 
+    private static final String DEVELOPMENT_PROPERTIES = "development.properties";
+
     private static final String ENV_MAVEN_EXECUTABLE = "MAVOR_MAVEN_EXECUTABLE";
     private static final String ENV_TEMP_DIR = "MAVOR_TEMP_DIR";
 
-    private final String mavenExecutable = Objects.requireNonNull(System.getProperty(ENV_MAVEN_EXECUTABLE));
-    private final String tempDir = Objects.requireNonNull(System.getProperty(ENV_TEMP_DIR));
+    private String mavenExecutable;
+    private String tempDir;
+
+    public Configuration() throws IOException {
+        ClassLoader classLoader = Thread.currentThread().getContextClassLoader();
+        InputStream developmentPropertiesStream = classLoader.getResourceAsStream(DEVELOPMENT_PROPERTIES);
+        if (Objects.nonNull(developmentPropertiesStream)) {
+            Properties developmentProperties = new Properties();
+            developmentProperties.load(developmentPropertiesStream);
+            initByProperties(developmentProperties);
+        } else {
+            initByProperties(System.getProperties());
+        }
+    }
+
+    private void initByProperties(Properties properties) {
+        mavenExecutable = properties.getProperty(ENV_MAVEN_EXECUTABLE);
+        tempDir = properties.getProperty(ENV_TEMP_DIR);
+    }
 
     public String getMavenExecutable() {
         return mavenExecutable;
@@ -17,4 +39,4 @@ public class Configuration {
     public String getTempDir() {
         return tempDir;
     }
-}
+}

src/main/java/de/devloop/mavor/servlet/DownloadJars.java

@@ -35,7 +35,16 @@ public class DownloadJars extends AuthenticatedServlet {
     private static final String PARAMETER_POM = "pom";
     private static final String PARAMETER_TYPE = "type";
 
-    private final Configuration configuration = new Configuration();
+    private Configuration configuration;
+
+    @Override
+    public void init() throws ServletException {
+        try {
+            configuration = new Configuration();
+        } catch (IOException e) {
+            throw new ServletException("Configuration Error", e);
+        }
+    }
 
     @Override
     protected void doAuthenticatedPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
@@ -93,7 +102,7 @@ public class DownloadJars extends AuthenticatedServlet {
     }
 
     private ExecutionResult executeMaven(File tempDirJars) throws IOException, InterruptedException {
-        String mavenCmd = String.format("%s dependency:copy-dependencies -DoutputDirectory=\"%s\"", configuration.getMavenExecutable(), tempDirJars.getCanonicalPath());
+        String mavenCmd = String.format("%s dependency:copy-dependencies -DoutputDirectory=%s", configuration.getMavenExecutable(), tempDirJars.getCanonicalPath());
         Process mvnProcess = Runtime.getRuntime().exec(mavenCmd, null, tempDirJars.getCanonicalFile());
         String stdout = new String(mvnProcess.getInputStream().readAllBytes(), StandardCharsets.UTF_8);
         String stderr = new String(mvnProcess.getErrorStream().readAllBytes(), StandardCharsets.UTF_8);

src/main/java/de/devloop/mavor/servlet/DownloadZip.java

@@ -16,7 +16,16 @@ public class DownloadZip extends AuthenticatedServlet {
 
     private static final String PARAMETER_FILENAME = "file";
 
-    private final Configuration configuration = new Configuration();
+    private Configuration configuration;
+
+    @Override
+    public void init() throws ServletException {
+        try {
+            configuration = new Configuration();
+        } catch (IOException e) {
+            throw new ServletException("Configuration Error", e);
+        }
+    }
 
     @Override
     protected void doAuthenticatedGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {