IVY-1615 implement retrieval of ivysettings from url in standalone.

Closes #91 pull request at github.com/apache/ant-ivy repo

asciidoc/release-notes.adoc

@@ -50,7 +50,7 @@ For details about the following changes, check our JIRA install at link:https://
 - FIX: ConcurrentModificationException in MessageLoggerHelper.sumupProblems (jira:IVY-1628[])
 
 
-- IMPROVEMENT:
+- IMPROVEMENT: Ivy command now accepts a URL for the -settings option (jira:IVY-1615[])
 
 - NEW:
 
@@ -219,3 +219,4 @@ Here is the list of people who have contributed source code and documentation up
 * Jaroslaw Wypychowski
 * Sven Zethelius
 * Aleksey Zhukov
+* Jason A. Guild

src/java/org/apache/ivy/Main.java

@@ -24,6 +24,8 @@ import java.io.PrintWriter;
 import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Method;
 import java.net.MalformedURLException;
+import java.net.URI;
+import java.net.URISyntaxException;
 import java.net.URL;
 import java.net.URLClassLoader;
 import java.util.ArrayList;
@@ -76,8 +78,8 @@ public final class Main {
         return new CommandLineParser()
                 .addCategory("settings options")
                 .addOption(
-                    new OptionBuilder("settings").arg("settingsfile")
-                            .description("use given file for settings").create())
+                    new OptionBuilder("settings").arg("settingsfile|url")
+                            .description("use given file or URL for settings").create())
                 .addOption(
                         new OptionBuilder("properties").arg("propertiesfile")
                             .description("use given file for properties not specified in settings").create())
@@ -515,17 +517,39 @@ public final class Main {
         if ("".equals(settingsPath)) {
             ivy.configureDefault();
         } else {
-            File conffile = new File(settingsPath);
-            if (!conffile.exists()) {
-                error("ivy configuration file not found: " + conffile);
-            } else if (conffile.isDirectory()) {
-                error("ivy configuration file is not a file: " + conffile);
+            final URI confUri = getSettingsURI(settingsPath);
+            if ("file".equals(confUri.getScheme())) {
+                File conffile = new File(confUri);
+                if (!conffile.exists()) {
+                    throw new IOException("ivy configuration file not found: " + conffile);
+                } else if (conffile.isDirectory()) {
+                    throw new IOException("ivy configuration file is not a file: " + conffile);
+                }
+                ivy.configure(conffile);
+            } else {
+                try {
+                    ivy.configure(confUri.toURL());
+                } catch (IOException ioe) {
+                    throw new IOException("ivy configuration failed to load from: " + settingsPath, ioe);
+                }
             }
-            ivy.configure(conffile);
         }
         return settings;
     }
 
+    private static URI getSettingsURI(String settingsPath) {
+        URI settingsUri;
+        try {
+            settingsUri = new URI(settingsPath);
+            if (settingsUri.getScheme() == null) {
+                settingsUri = new File(settingsPath).toURI();
+            }
+        } catch (URISyntaxException badUriEx) {
+            return new File(settingsPath).toURI();
+        }
+        return settingsUri;
+    }
+
     private static void initMessage(CommandLine line, Ivy ivy) {
         if (line.hasOption("debug")) {
             ivy.getLoggerEngine().pushLogger(new DefaultMessageLogger(Message.MSG_DEBUG));

test/java/org/apache/ivy/MainTest.java

@@ -29,6 +29,7 @@ import org.junit.rules.ExpectedException;
 import org.junit.rules.TemporaryFolder;
 
 import java.io.File;
+import java.net.URL;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.nio.file.Paths;
@@ -206,6 +207,18 @@ public class MainTest {
         assertTrue("pom file hasn't been generated at " + pomFilePath, new File(pomFilePath).isFile());
     }
 
+    /**
+     * Tests that the ivy command can use a URL for the {@code -settings} option. See IVY-1615
+     */
+    @Test
+    public void testSettingsURL() throws Exception {
+        final URL settingsURL = new File("test/repositories/ivysettings.xml").toURI().toURL();
+        run(new String[] {"-settings", settingsURL.toString(), "-ivy",
+                "test/repositories/1/org1/mod1.1/ivys/ivy-1.0.xml"});
+
+        assertTrue(new File("build/cache/org1/mod1.2/ivy-2.0.xml").exists());
+    }
+
     private void run(String[] args) throws Exception {
         Main.run(Main.getParser(), args);
     }