Auto generate node ID

flytekit-java/pom.xml

@@ -73,5 +73,10 @@
       <artifactId>mockito-core</artifactId>
       <scope>test</scope>
     </dependency>
+    <dependency>
+      <groupId>org.mockito</groupId>
+      <artifactId>mockito-junit-jupiter</artifactId>
+      <scope>test</scope>
+    </dependency>
   </dependencies>
 </project>

flytekit-java/src/main/java/org/flyte/flytekit/SdkCondition.java

@@ -54,13 +54,6 @@ public SdkBranchNode apply(
       List<String> upstreamNodeIds,
       @Nullable SdkNodeMetadata metadata,
       Map<String, SdkBindingData> inputs) {
-    if (metadata != null) {
-      throw new IllegalArgumentException("invariant failed: metadata must be null");
-    }
-    if (!inputs.isEmpty()) {
-      throw new IllegalArgumentException("invariant failed: inputs must be empty");
-    }
-
     SdkBranchNode.Builder nodeBuilder = new SdkBranchNode.Builder(builder);
 
     for (SdkConditionCase case_ : cases) {

flytekit-java/src/main/java/org/flyte/flytekit/SdkContainerTask.java

@@ -53,11 +53,6 @@ public String getType() {
     return "raw-container";
   }
 
-  /** Specifies task name. */
-  public String getName() {
-    return getClass().getName();
-  }
-
   /** Specifies task input type. */
   public SdkType<InputT> getInputType() {
     return inputType;

flytekit-java/src/main/java/org/flyte/flytekit/SdkDynamicWorkflowTask.java

@@ -36,10 +36,6 @@ public String getType() {
     return "dynamic";
   }
 
-  public String getName() {
-    return getClass().getName();
-  }
-
   public SdkType<InputT> getInputType() {
     return inputType;
   }

flytekit-java/src/main/java/org/flyte/flytekit/SdkNode.java

@@ -58,6 +58,6 @@ public SdkNode apply(String id, SdkTransform transform) {
     List<String> upstreamNodeIds =
         getOutputs().isEmpty() ? Collections.singletonList(getNodeId()) : Collections.emptyList();
 
-    return builder.applyInternal(id, transform, upstreamNodeIds, /*metadata=*/ null, getOutputs());
+    return builder.applyInternal(id, transform, upstreamNodeIds, getOutputs());
   }
 }

flytekit-java/src/main/java/org/flyte/flytekit/SdkNodeNamePolicy.java

@@ -0,0 +1,85 @@
+/*
+ * Copyright 2021 Flyte Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+package org.flyte.flytekit;
+
+import java.util.Locale;
+import java.util.Map;
+import java.util.concurrent.ThreadLocalRandom;
+import java.util.concurrent.atomic.AtomicInteger;
+import java.util.regex.Pattern;
+
+/**
+ * Controls the default node id and node name policy when applying {@link SdkTransform} to {@link
+ * SdkWorkflowBuilder}. When using {@link SdkWorkflowBuilder#apply(SdkTransform)} or {@link
+ * SdkWorkflowBuilder#apply(SdkTransform, Map)} then the node id used would be the one returned by
+ * {@link #nextNodeId()}. Also, if a node name haven't been set by the user, then {@link
+ * #toNodeName(String)} would be used.
+ */
+class SdkNodeNamePolicy {
+  private static final Pattern UPPER_AFTER_LOWER_PATTERN = Pattern.compile("([a-z])([A-Z]+)");
+  private static final int RND_PREFIX_SIZE = 4;
+
+  private final String nodeIdPrefix;
+  private final AtomicInteger nodeIdSuffix;
+
+  SdkNodeNamePolicy() {
+    this.nodeIdPrefix = randomPrefix();
+    this.nodeIdSuffix = new AtomicInteger();
+  }
+
+  /**
+   * Returns a unique node ids in the format {@code <prefix>-n<consecutive-number>}, where prefix is
+   * a random, but shared among all ids for this object, set of character in the format {@code
+   * wRRRR} and {@code R} is a random letter in {@code a-z} range.
+   *
+   * @return next unique node id for this policy.
+   */
+  String nextNodeId() {
+    return nodeIdPrefix + "n" + nodeIdSuffix.getAndIncrement();
+  }
+
+  /**
+   * Returns a node appropriate name for a given transformation name. The transformation done are
+   *
+   * <ul>
+   *   <li>Package name is removed
+   *   <li>CamelCase is transformed to kebab-case
+   *   <li>$ is transformed to -
+   * </ul>
+   *
+   * <p>For example {@code com.example.Outer$InnerTask} get translated to {@code outer-inner-task}.
+   *
+   * @return node name.
+   */
+  String toNodeName(String name) {
+    String lastPart = name.substring(name.lastIndexOf('.') + 1);
+    return UPPER_AFTER_LOWER_PATTERN
+        .matcher(lastPart)
+        .replaceAll("$1-$2")
+        .toLowerCase(Locale.ROOT)
+        .replaceAll("\\$", "-");
+  }
+
+  // Returns random prefix in the following format "wqjoz-"
+  private static String randomPrefix() {
+    return "w"
+        + ThreadLocalRandom.current()
+            .ints(RND_PREFIX_SIZE, 'a', 'z' + 1)
+            .collect(StringBuilder::new, StringBuilder::appendCodePoint, StringBuilder::append)
+            .append('-');
+  }
+}

flytekit-java/src/main/java/org/flyte/flytekit/SdkPartialTransform.java

@@ -103,6 +103,14 @@ public SdkTransform withNameOverride(String name) {
     return new SdkPartialTransform(transform, fixedInputs, extraUpstreamNodeIds, mergedMetadata);
   }
 
+  @Override
+  SdkTransform withNameOverrideIfNotSet(String name) {
+    if (metadata != null && metadata.name() != null) {
+      return this;
+    }
+    return withNameOverride(name);
+  }
+
   @Override
   public SdkTransform withTimeoutOverride(Duration timeout) {
     requireNonNull(timeout, "Timeout override cannot be null");
@@ -114,6 +122,11 @@ public SdkTransform withTimeoutOverride(Duration timeout) {
     return new SdkPartialTransform(transform, fixedInputs, extraUpstreamNodeIds, mergedMetadata);
   }
 
+  @Override
+  public String getName() {
+    return transform.getName();
+  }
+
   @Override
   public SdkNode apply(
       SdkWorkflowBuilder builder,

flytekit-java/src/main/java/org/flyte/flytekit/SdkRemoteLaunchPlan.java

@@ -58,6 +58,11 @@ public static <InputT, OutputT> SdkRemoteLaunchPlan<InputT, OutputT> create(
         .build();
   }
 
+  @Override
+  public String getName() {
+    return name();
+  }
+
   @Override
   public SdkNode apply(
       SdkWorkflowBuilder builder,

flytekit-java/src/main/java/org/flyte/flytekit/SdkRemoteTask.java

@@ -60,6 +60,11 @@ public static <InputT, OutputT> SdkRemoteTask<InputT, OutputT> create(
         .build();
   }
 
+  @Override
+  public String getName() {
+    return name();
+  }
+
   @Override
   public SdkNode apply(
       SdkWorkflowBuilder builder,

flytekit-java/src/main/java/org/flyte/flytekit/SdkRunnableTask.java

@@ -50,10 +50,6 @@ public String getType() {
     return "java-task";
   }
 
-  public String getName() {
-    return getClass().getName();
-  }
-
   public SdkType<InputT> getInputType() {
     return inputType;
   }

flytekit-java/src/main/java/org/flyte/flytekit/SdkTransform.java

@@ -78,10 +78,18 @@ public SdkTransform withNameOverride(String name) {
     return SdkPartialTransform.of(this, metadata);
   }
 
+  SdkTransform withNameOverrideIfNotSet(String name) {
+    return withNameOverride(name);
+  }
+
   public SdkTransform withTimeoutOverride(Duration timeout) {
     requireNonNull(timeout, "Timeout override cannot be null");
 
     SdkNodeMetadata metadata = SdkNodeMetadata.builder().timeout(timeout).build();
     return SdkPartialTransform.of(this, metadata);
   }
+
+  public String getName() {
+    return getClass().getName();
+  }
 }

flytekit-java/src/main/java/org/flyte/flytekit/SdkWorkflow.java

@@ -27,10 +27,6 @@
 
 public abstract class SdkWorkflow extends SdkTransform {
 
-  public String getName() {
-    return getClass().getName();
-  }
-
   public abstract void expand(SdkWorkflowBuilder builder);
 
   @Override

flytekit-java/src/main/java/org/flyte/flytekit/SdkWorkflowBuilder.java

@@ -27,54 +27,80 @@
 import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.Objects;
 import javax.annotation.Nullable;
 import org.flyte.api.v1.LiteralType;
 import org.flyte.api.v1.SimpleType;
 import org.flyte.api.v1.WorkflowTemplate;
 
 public class SdkWorkflowBuilder {
+
   private final Map<String, SdkNode> nodes;
   private final Map<String, SdkBindingData> inputs;
   private final Map<String, SdkBindingData> outputs;
   private final Map<String, String> inputDescriptions;
   private final Map<String, String> outputDescriptions;
+  private final SdkNodeNamePolicy sdkNodeNamePolicy;
 
   public SdkWorkflowBuilder() {
+    this(new SdkNodeNamePolicy());
+  }
+
+  // VisibleForTesting
+  SdkWorkflowBuilder(SdkNodeNamePolicy sdkNodeNamePolicy) {
     // Using LinkedHashMap to preserve declaration order
     this.nodes = new LinkedHashMap<>();
     this.inputs = new LinkedHashMap<>();
     this.outputs = new LinkedHashMap<>();
 
     this.inputDescriptions = new HashMap<>();
     this.outputDescriptions = new HashMap<>();
+
+    this.sdkNodeNamePolicy = sdkNodeNamePolicy;
   }
 
   public SdkNode apply(String nodeId, SdkTransform transform) {
     return apply(nodeId, transform, emptyMap());
   }
 
   public SdkNode apply(String nodeId, SdkTransform transform, Map<String, SdkBindingData> inputs) {
-    return applyInternal(nodeId, transform, emptyList(), /*metadata=*/ null, inputs);
+    return applyInternal(nodeId, transform, emptyList(), inputs);
+  }
+
+  public SdkNode apply(SdkTransform transform) {
+    return apply(/*nodeId=*/ null, transform, emptyMap());
+  }
+
+  public SdkNode apply(SdkTransform transform, Map<String, SdkBindingData> inputs) {
+    return applyInternal(/*nodeId=*/ null, transform, emptyList(), inputs);
   }
 
-  protected SdkNode applyInternal(
-      String nodeId,
+  SdkNode applyInternal(
+      @Nullable String nodeId,
       SdkTransform transform,
       List<String> upstreamNodeIds,
-      @Nullable SdkNodeMetadata metadata,
       Map<String, SdkBindingData> inputs) {
 
-    if (nodes.containsKey(nodeId)) {
+    String actualNodeId = Objects.requireNonNullElseGet(nodeId, sdkNodeNamePolicy::nextNodeId);
+
+    if (nodes.containsKey(actualNodeId)) {
       CompilerError error =
           CompilerError.create(
               CompilerError.Kind.DUPLICATE_NODE_ID,
-              nodeId,
+              actualNodeId,
               "Trying to insert two nodes with the same id.");
 
       throw new CompilerException(error);
     }
 
-    SdkNode sdkNode = transform.apply(this, nodeId, upstreamNodeIds, metadata, inputs);
+    String fallbackNodeName =
+        Objects.requireNonNullElseGet(
+            nodeId, () -> sdkNodeNamePolicy.toNodeName(transform.getName()));
+
+    SdkNode sdkNode =
+        transform
+            .withNameOverrideIfNotSet(fallbackNodeName)
+            .apply(this, actualNodeId, upstreamNodeIds, null, inputs);
     nodes.put(sdkNode.getNodeId(), sdkNode);
 
     return sdkNode;