Add CLI readme + improvements

.gitignore

@@ -1,6 +1,7 @@
 # Ignore Gradle project-specific cache directory
 .gradle
 .idea
+.nextflow
 
 # Ignore Gradle build output directory
 build

README.md

@@ -32,6 +32,29 @@ MigTool is designed to be embedded in the target app requiring. Use the followin
 
 ``` 
 
+## Binary release 
+
+MigTool is also released as a pre-compiled Linux binary including H2 and MySQL drivers. To use it, download the 
+binary package at [this link](https://github.com/seqeralabs/migtool/releases/latest), then grant execute permission, 
+finally run it following the example below:
+
+```
+./migtool \
+   --user <foo> \
+   --password <some secret> 
+   --url <jdbc:mysql://host.com:3306/some-schema>
+   --location <file:/some/path/to/migration/scripts.sql>
+```
+                                                        
+#### Options 
+
+* `user`: Target database connection username.
+* `password`: Target database connection password.
+* `url`: Target database JDBC connection URL.
+* `location`: File system path where migration scripts are located. Path must be prefixed with `file:`.
+* `dialect`: Either `mysql` or `h2` (optional).
+* `driver`: JDBC driver class name to connect the target database (optional).
+
 ## License 
 
 [Mozilla Public License v2.0](LICENSE.txt)

src/main/java/io/seqera/migtool/App.java

@@ -5,6 +5,10 @@
 import picocli.CommandLine;
 import picocli.CommandLine.Command;
 import picocli.CommandLine.Option;
+
+import static io.seqera.migtool.Helper.driverFromUrl;
+import static io.seqera.migtool.Helper.dialectFromUrl;
+
 /**
  * Mig tool main launcher
  *
@@ -30,8 +34,8 @@ public class App implements Callable<Integer> {
     @Option(names = {"--driver"}, description = "JDBC driver class name")
     private String driver;
 
-    @Option(names = {"--locations"}, description = "DB migration scripts location path (local path should be prefixed with `file:`)")
-    private String locations;
+    @Option(names = {"--location"}, description = "DB migration scripts location path (local path should be prefixed with `file:`)")
+    private String location;
 
     @Option(names = {"--pattern"}, description = "DB migration scripts file names pattern")
     private String pattern = "^m(\\d+)__(.+)";
@@ -44,9 +48,9 @@ public Integer call() throws Exception {
                 .withUser(username)
                 .withPassword(password)
                 .withUrl(url)
-                .withDialect(dialect)
-                .withDriver(driver)
-                .withLocations(locations)
+                .withDialect(dialect!=null ? dialect : dialectFromUrl(url))
+                .withDriver(driver!=null ? driver : driverFromUrl(url))
+                .withLocations(location)
                 .withPattern(pattern);
 
         try {
@@ -63,6 +67,7 @@ public Integer call() throws Exception {
         }
     }
 
+
     public static void main(String[] args) {
         int exitCode = new CommandLine(new App()).execute(args);
         System.exit(exitCode);

src/main/java/io/seqera/migtool/Helper.java

@@ -201,4 +201,19 @@ private static void closeWithWarning(Closeable closeable) {
         tryClose(closeable);
     }
 
+    static public String dialectFromUrl(String url) {
+        if( url==null )
+            return null;
+        String[] parts = url.split(":");
+        return parts.length > 1 ? parts[1] : null;
+    }
+
+    static public String driverFromUrl(String url) {
+        final String dialect = dialectFromUrl(url);
+        if( "mysql".equals(dialect) )
+            return "com.mysql.cj.jdbc.Driver";
+        if( "h2".equals(dialect))
+            return "org.h2.Driver";
+        return null;
+    }
 }

src/nativeCliTest/groovy/io/seqera/migtool/MysqlTest.groovy

@@ -28,9 +28,7 @@ class MysqlTest extends Specification {
                 '-u', container.username,
                 '-p', container.password,
                 '--url', container.jdbcUrl,
-                '--driver', 'com.mysql.cj.jdbc.Driver',
-                '--dialect', 'mysql',
-                '--locations', 'file:src/test/resources/migrate-db/mysql' ]
+                '--location', 'file:src/test/resources/migrate-db/mysql' ]
 
         when:
         println "Running: ${CLI.join( )}"

src/test/groovy/io/seqera/migtool/HelperTest.groovy

@@ -34,4 +34,17 @@ class HelperTest extends Specification {
         Helper.computeSha256('Hola mundo' ) == 'ca8f60b2cc7f05837d98b208b57fb6481553fc5f1219d59618fd025002a66f5c'
     }
 
+    def 'should parse dialect from url' () {
+        expect:
+        Helper.dialectFromUrl() == null
+        Helper.dialectFromUrl('jdbc:h2:file:./.db/h2/tower') == 'h2'
+        Helper.dialectFromUrl('jdbc:mysql://foo.com:3306/licman') == 'mysql'
+    }
+
+    def 'should get driver from url' () {
+        expect:
+        Helper.driverFromUrl() == null
+        Helper.driverFromUrl('jdbc:h2:file:./.db/h2/tower') == 'org.h2.Driver'
+        Helper.driverFromUrl('jdbc:mysql://foo.com:3306/licman') == 'com.mysql.cj.jdbc.Driver'
+    }
 }