add support for -n / --no-exec command line flag

src/main/java/jvcl/main/Jvcl.java

@@ -19,6 +19,7 @@ public class Jvcl extends BaseMain<JvclOptions> {
     @Override protected void run() throws Exception {
         final JvclOptions options = getOptions();
         final JSpec spec = options.getSpec();
+        final boolean noExec = options.isNoExec();
 
         if (empty(spec.getAssets())) {
             err(">>> jvcl: no assets defined in spec");
@@ -34,7 +35,7 @@ public class Jvcl extends BaseMain<JvclOptions> {
         final AssetManager assetManager = new AssetManager(toolbox, getOptions().scratchDir());
         Arrays.stream(spec.getAssets()).forEach(assetManager::defineAsset);
 
-        final OperationEngine opEngine = new OperationEngine(toolbox, assetManager);
+        final OperationEngine opEngine = new OperationEngine(toolbox, assetManager, noExec);
         Arrays.stream(spec.getOperations()).forEach(opEngine::perform);
 
         final int opCount = spec.getOperations().length;

src/main/java/jvcl/model/operation/JOperation.java

@@ -31,6 +31,7 @@ public abstract class JOperation {
 
     @Getter @Setter private String operation;
     @Getter @Setter private JsonNode creates;
+    @Getter @Setter private boolean noExec = false;
 
     public String hash(JAsset[] sources) { return hash(sources, null); }
 

src/main/java/jvcl/operation/exec/ConcatExec.java

@@ -14,7 +14,6 @@ import java.util.List;
 import java.util.Map;
 
 import static org.cobbzilla.util.io.FileUtil.abs;
-import static org.cobbzilla.util.system.CommandShell.execScript;
 
 @Slf4j
 public class ConcatExec extends ExecBase<ConcatOperation> {
@@ -51,7 +50,7 @@ public class ConcatExec extends ExecBase<ConcatOperation> {
         final String script = renderScript(toolbox, ctx, CONCAT_RECODE_TEMPLATE_1);
 
         log.debug("operate: running script: "+script);
-        final String scriptOutput = execScript(script);
+        final String scriptOutput = exec(script, op.isNoExec());
         log.debug("operate: command output: "+scriptOutput);
         assetManager.addOperationAsset(output);
     }

src/main/java/jvcl/operation/exec/ExecBase.java

@@ -12,6 +12,7 @@ import java.util.Map;
 
 import static org.cobbzilla.util.io.FileUtil.abs;
 import static org.cobbzilla.util.io.FileUtil.basename;
+import static org.cobbzilla.util.system.CommandShell.execScript;
 
 @Slf4j
 public abstract class ExecBase<OP extends JOperation> {
@@ -36,4 +37,13 @@ public abstract class ExecBase<OP extends JOperation> {
             return defaultOutfile;
         }
     }
+
+    public String exec(String script, boolean noExec) {
+        if (noExec) {
+            System.out.println(script);
+            return "";
+        } else {
+            return execScript(script);
+        }
+    }
 }

src/main/java/jvcl/operation/exec/KenBurnsExec.java

@@ -20,7 +20,6 @@ import static java.math.BigDecimal.ZERO;
 import static jvcl.service.Toolbox.TWO;
 import static jvcl.service.Toolbox.divideBig;
 import static org.cobbzilla.util.io.FileUtil.abs;
-import static org.cobbzilla.util.system.CommandShell.execScript;
 
 @Slf4j
 public class KenBurnsExec extends ExecBase<KenBurnsOperation> {
@@ -97,7 +96,7 @@ public class KenBurnsExec extends ExecBase<KenBurnsOperation> {
         final String script = renderScript(toolbox, ctx, KEN_BURNS_TEMPLATE);
 
         log.debug("operate: running script: "+script);
-        final String scriptOutput = execScript(script);
+        final String scriptOutput = exec(script, op.isNoExec());
         log.debug("operate: command output: "+scriptOutput);
         assetManager.addOperationAsset(output);
     }

src/main/java/jvcl/operation/exec/LetterboxExec.java

@@ -14,7 +14,6 @@ import java.util.Map;
 
 import static org.cobbzilla.util.daemon.ZillaRuntime.die;
 import static org.cobbzilla.util.string.StringUtil.safeShellArg;
-import static org.cobbzilla.util.system.CommandShell.execScript;
 
 @Slf4j
 public class LetterboxExec extends SingleOrMultiSourceExecBase<LetterboxOperation> {
@@ -71,7 +70,7 @@ public class LetterboxExec extends SingleOrMultiSourceExecBase<LetterboxOperatio
         final String script = renderScript(toolbox, ctx, LETTERBOX_TEMPLATE);
 
         log.debug("operate: running script: "+script);
-        final String scriptOutput = execScript(script);
+        final String scriptOutput = exec(script, op.isNoExec());
         log.debug("operate: command output: "+scriptOutput);
         if (output == subOutput) {
             assetManager.addOperationAsset(output);

src/main/java/jvcl/operation/exec/OverlayExec.java

@@ -15,7 +15,6 @@ import java.util.HashMap;
 import java.util.Map;
 
 import static org.cobbzilla.util.io.FileUtil.abs;
-import static org.cobbzilla.util.system.CommandShell.execScript;
 
 @Slf4j
 public class OverlayExec extends ExecBase<OverlayOperation> {
@@ -59,7 +58,7 @@ public class OverlayExec extends ExecBase<OverlayOperation> {
         final String script = renderScript(toolbox, ctx, OVERLAY_TEMPLATE);
 
         log.debug("operate: running script: "+script);
-        final String scriptOutput = execScript(script);
+        final String scriptOutput = exec(script, op.isNoExec());
         log.debug("operate: command output: "+scriptOutput);
         assetManager.addOperationAsset(output);
     }

src/main/java/jvcl/operation/exec/ScaleExec.java

@@ -13,8 +13,6 @@ import java.math.BigDecimal;
 import java.util.HashMap;
 import java.util.Map;
 
-import static org.cobbzilla.util.system.CommandShell.execScript;
-
 @Slf4j
 public class ScaleExec extends SingleOrMultiSourceExecBase<ScaleOperation> {
 
@@ -58,7 +56,7 @@ public class ScaleExec extends SingleOrMultiSourceExecBase<ScaleOperation> {
         final String script = renderScript(toolbox, ctx, SCALE_TEMPLATE);
 
         log.debug("operate: running script: "+script);
-        final String scriptOutput = execScript(script);
+        final String scriptOutput = exec(script, op.isNoExec());
         log.debug("operate: command output: "+scriptOutput);
         if (output == subOutput) {
             assetManager.addOperationAsset(output);

src/main/java/jvcl/operation/exec/SplitExec.java

@@ -17,7 +17,6 @@ import java.util.Map;
 import static org.cobbzilla.util.daemon.ZillaRuntime.die;
 import static org.cobbzilla.util.io.FileUtil.abs;
 import static org.cobbzilla.util.io.FileUtil.mkdirOrDie;
-import static org.cobbzilla.util.system.CommandShell.execScript;
 
 @Slf4j
 public class SplitExec extends ExecBase<SplitOperation> {
@@ -76,7 +75,7 @@ public class SplitExec extends ExecBase<SplitOperation> {
             final String script = renderScript(toolbox, ctx, SPLIT_TEMPLATE);
 
             log.debug("operate: running script: "+script);
-            final String scriptOutput = execScript(script);
+            final String scriptOutput = exec(script, op.isNoExec());
             log.debug("operate: command output: "+scriptOutput);
             assetManager.addOperationAssetSlice(output, slice);
         }

src/main/java/jvcl/operation/exec/TrimExec.java

@@ -13,8 +13,6 @@ import java.math.BigDecimal;
 import java.util.HashMap;
 import java.util.Map;
 
-import static org.cobbzilla.util.system.CommandShell.execScript;
-
 @Slf4j
 public class TrimExec extends SingleOrMultiSourceExecBase<TrimOperation> {
 
@@ -55,7 +53,7 @@ public class TrimExec extends SingleOrMultiSourceExecBase<TrimOperation> {
         final String script = renderScript(toolbox, ctx, TRIM_TEMPLATE);
 
         log.debug("operate: running script: "+script);
-        final String scriptOutput = execScript(script);
+        final String scriptOutput = exec(script, op.isNoExec());
         log.debug("operate: command output: "+scriptOutput);
         if (output == subOutput) {
             assetManager.addOperationAsset(output);

src/main/java/jvcl/service/OperationEngine.java

@@ -1,18 +1,21 @@
 package jvcl.service;
 
 import jvcl.model.operation.JOperation;
+import lombok.Getter;
 
 public class OperationEngine {
 
     private final Toolbox toolbox;
     private final AssetManager assetManager;
+    @Getter private final boolean noExec;
 
-    public OperationEngine(Toolbox toolbox, AssetManager assetManager) {
+    public OperationEngine(Toolbox toolbox, AssetManager assetManager, boolean noExec) {
         this.toolbox =  toolbox;
         this.assetManager = assetManager;
+        this.noExec = noExec;
     }
 
     public void perform(JOperation op) {
-        op.getExec().operate(op, toolbox, assetManager);
+        op.setNoExec(noExec).getExec().operate(op, toolbox, assetManager);
     }
 }