Add tools endpoint for invoking taskdsl-graph conversion

- Convert to Resource responses
- Make DSLMessages consistent - lower case start char and no trailing period
- Enable TaskValidationProblem to format themselves for client transmission
- Introduce `ToolsControllerTests` which tests tools endpoints

Author: aclement

spring-cloud-dataflow-core/src/main/java/org/springframework/cloud/dataflow/core/dsl/DSLMessage.java

@@ -93,25 +93,25 @@ public enum DSLMessage {
 	EXPECTED_WHITESPACE_AFTER_LABEL_COLON(ERROR, 147, "whitespace is expected after an app label"), //
 	EXPECTED_STREAM_NAME_AFTER_LABEL_COLON(ERROR, 148, "stream name is expected after an app label"), //
 	// These relate specifically to the composed task DSL
-	TASK_DOUBLE_AND_REQUIRED(ERROR, 150, "task dsl flow requires a pair of &, not just one."), //
-	TASK_DOUBLE_OR_REQUIRED(ERROR, 151, "task dsl requires a pair of '|'."), //
+	TASK_DOUBLE_AND_REQUIRED(ERROR, 150, "task dsl flow requires a pair of &, not just one"), //
+	TASK_DOUBLE_OR_REQUIRED(ERROR, 151, "task dsl requires a pair of '|'"), //
 	TASK_HYPHEN_EXPECTED_USE_FOR_TRANSITION(ERROR, 152, "expected '->' and not just the hyphen"), //
 	TASK_MISSING_TRANSITION_ARROW(ERROR, 153, "expected '->' to follow state when specifying transition"), //
 	TASK_UNQUOTED_TRANSITION_CHECK_MUST_BE_NUMBER(ERROR, 154, "transition conditions must be quoted literals, numerics or '*' but ''{0}'' is not"), //
 	TASK_NO_LABELS_ON_PARENS(ERROR, 155, "labels cannot be specified on parenthesized groups"), //
-	TASK_NO_DOUBLE_LABELS(ERROR, 156, "Double labels are not supported"), //
-	TASK_ARROW_SHOULD_BE_PRECEDED_BY_CODE(ERROR, 157, "Transition arrow must be preceeded by the exit code that should drive the transition"), //
-	TASK_VALIDATION_SECONDARY_SEQUENCES_MUST_BE_NAMED(ERROR, 158, "Secondary sequences must have labels or are unreachable"), //
-	TASK_VALIDATION_DUPLICATE_LABEL(ERROR, 159, "This label has already been defined"), //
-	TASK_VALIDATION_TRANSITION_TARGET_LABEL_UNDEFINED(ERROR, 160, "Transition specifies an undefined label"), //
-	TASK_ELEMENT_IN_COMPOSED_DEFINITION_DOES_NOT_EXIST(ERROR, 161, "Task in composed task definition does not exist"), //
-	TASK_UNEXPECTED_DATA(ERROR, 162, "Unexpected data in task definition ''{0}''"), //
-	TASK_MORE_INPUT(ERROR, 163, "After parsing a valid task, there is still more data: ''{0}''"), //
-	TASK_VALIDATION_LABEL_CLASHES_WITH_TASKAPP_NAME(ERROR, 164, "The label clashes with an existing unlabeled task application name"), //
-	TASK_VALIDATION_APP_NAME_CLASHES_WITH_LABEL(ERROR, 165, "The app name clashes with an existing label"), //
-	TASK_VALIDATION_APP_NAME_ALREADY_IN_USE(ERROR, 166, "Duplicate app name. Use a label to ensure uniqueness"), //
-	TASK_VALIDATION_SPLIT_WITH_ONE_FLOW(ERROR, 167, "Unnecessary use of split construct when only one flow to execute in parallel"), //
-	TASK_ARGUMENTS_NOT_ALLOWED_UNLESS_IN_APP_MODE(ERROR, 168, "Arguments not allowed unless parser is in app mode"), //
+	TASK_NO_DOUBLE_LABELS(ERROR, 156, "double labels are not supported"), //
+	TASK_ARROW_SHOULD_BE_PRECEDED_BY_CODE(ERROR, 157, "transition arrow must be preceeded by the exit code that should drive the transition"), //
+	TASK_VALIDATION_SECONDARY_SEQUENCES_MUST_BE_NAMED(ERROR, 158, "secondary sequences must have labels or are unreachable"), //
+	TASK_VALIDATION_DUPLICATE_LABEL(ERROR, 159, "this label has already been defined"), //
+	TASK_VALIDATION_TRANSITION_TARGET_LABEL_UNDEFINED(ERROR, 160, "transition specifies an undefined label"), //
+	TASK_ELEMENT_IN_COMPOSED_DEFINITION_DOES_NOT_EXIST(ERROR, 161, "task in composed task definition does not exist"), //
+	TASK_UNEXPECTED_DATA(ERROR, 162, "unexpected data in task definition ''{0}''"), //
+	TASK_MORE_INPUT(ERROR, 163, "after parsing a valid task, there is still more data: ''{0}''"), //
+	TASK_VALIDATION_LABEL_CLASHES_WITH_TASKAPP_NAME(ERROR, 164, "the label clashes with an existing unlabeled task application name"), //
+	TASK_VALIDATION_APP_NAME_CLASHES_WITH_LABEL(ERROR, 165, "the app name clashes with an existing label"), //
+	TASK_VALIDATION_APP_NAME_ALREADY_IN_USE(ERROR, 166, "duplicate app name. Use a label to ensure uniqueness"), //
+	TASK_VALIDATION_SPLIT_WITH_ONE_FLOW(ERROR, 167, "unnecessary use of split construct when only one flow to execute in parallel"), //
+	TASK_ARGUMENTS_NOT_ALLOWED_UNLESS_IN_APP_MODE(ERROR, 168, "arguments not allowed unless parser is in app mode"), //
 	;
 
 	private Kind kind;

spring-cloud-dataflow-core/src/main/java/org/springframework/cloud/dataflow/core/dsl/ParseException.java

@@ -16,6 +16,9 @@
 
 package org.springframework.cloud.dataflow.core.dsl;
 
+import java.util.HashMap;
+import java.util.Map;
+
 /**
  * Root exception for DSL parsing related exceptions. Rather than holding a
  * hard coded string indicating the problem, it records a message key and
@@ -95,4 +98,23 @@ public final int getPosition() {
 		return position;
 	}
 
+	/**
+	 * Produce a simple map of information about the exception that
+	 * can be sent to the client for display.
+	 * @return map of simple information including message and position
+	 */
+	public Map<String, Object> toExceptionDescriptor() {
+		Map<String, Object> descriptor = new HashMap<>();
+		String text = null;
+		if (message != null) {
+			text = message.formatMessage(position, inserts);
+		}
+		else {
+			text = super.getMessage();
+		}
+		descriptor.put("message", text);
+		descriptor.put("position", position);
+		return descriptor;
+	}
+
 }

spring-cloud-dataflow-core/src/main/java/org/springframework/cloud/dataflow/core/dsl/TaskValidationProblem.java

@@ -16,6 +16,9 @@
 
 package org.springframework.cloud.dataflow.core.dsl;
 
+import java.util.HashMap;
+import java.util.Map;
+
 /**
  * After parsing a task definition from a DSL string, the validation visitor may optionally run.
  * Even though it parses successfully there may be issues with how the definition is constructed. The
@@ -74,4 +77,17 @@ private int getStartOfLine(int position) {
 		return 0;
 	}
 
+	/**
+	 * Produce a simple map of information about the exception that
+	 * can be sent to the client for display.
+	 * @return map of simple information including message and position
+	 */
+	public Map<String, Object> toExceptionDescriptor() {
+		Map<String, Object> descriptor = new HashMap<>();
+		String text = message.formatMessage(offset);
+		descriptor.put("message", text);
+		descriptor.put("position", offset);
+		return descriptor;
+	}
+
 }

spring-cloud-dataflow-core/src/main/java/org/springframework/cloud/dataflow/core/dsl/graph/Graph.java

@@ -310,34 +310,17 @@ private int countLinksWithoutTransitions(List<Link> links) {
 
 	private void printNode(StringBuilder graphText, Node node, List<Node> unvisitedNodes) {
 		unvisitedNodes.remove(node);
-		// What to generate depends on whether it is a job definition or reference
-//		if (node.metadata != null && node.metadata.containsKey(Node.METADATAKEY_JOBMODULENAME)) {
-//			graphText.append(node.metadata.get(Node.METADATAKEY_JOBMODULENAME)).append(" ");
-//			graphText.append(node.name).append(" ");
-////			if (node.properties != null) {
-////				int count = 0;
-////				for (Map.Entry<String, String> entry : node.properties.entrySet()) {
-////					if (count > 0) {
-////						graphText.append(" ");
-////					}
-////					graphText.append("--").append(entry.getKey()).append("=").append(entry.getValue());
-////					count++;
-////				}
-////			}
-//		}
-//		else {
-			String nameInDSL = node.name;
-			if (node.getLabel()!=null) {
-				graphText.append(node.getLabel()).append(": ");
+		String nameInDSL = node.name;
+		if (node.getLabel() != null) {
+			graphText.append(node.getLabel()).append(": ");
+		}
+		graphText.append(nameInDSL);
+		if (node.properties != null) {
+			for (Map.Entry<String, String> entry : node.properties.entrySet()) {
+				graphText.append(" ");
+				graphText.append("--").append(entry.getKey()).append("=").append(entry.getValue());
 			}
-			graphText.append(nameInDSL);
-//			if (node.properties != null) {
-//				for (Map.Entry<String, String> entry : node.properties.entrySet()) {
-//					graphText.append(" ");
-//					graphText.append("--").append(entry.getKey()).append("=").append(entry.getValue());
-//				}
-//			}
-//		}
+		}
 	}
 
 	private void followLink(StringBuilder graphText, Link link, Node nodeToFinishFollowingAt,

spring-cloud-dataflow-core/src/main/java/org/springframework/cloud/dataflow/core/dsl/graph/Link.java

@@ -21,13 +21,16 @@
 
 import com.fasterxml.jackson.annotation.JsonIgnore;
 import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
+import com.fasterxml.jackson.annotation.JsonInclude;
+import com.fasterxml.jackson.annotation.JsonInclude.Include;
 
 /**
  * Represents a link in a {@link Graph} object that Flo will display as a link.
  *
  * @author Andy Clement
  */
 @JsonIgnoreProperties(ignoreUnknown = true)
+@JsonInclude(Include.NON_EMPTY)
 public class Link {
 
 	public final static String PROPERTY_TRANSITION_NAME = "transitionName";

spring-cloud-dataflow-core/src/main/java/org/springframework/cloud/dataflow/core/dsl/graph/Node.java

@@ -21,16 +21,19 @@
 
 import com.fasterxml.jackson.annotation.JsonIgnore;
 import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
+import com.fasterxml.jackson.annotation.JsonInclude;
+import com.fasterxml.jackson.annotation.JsonInclude.Include;
 
 /**
  * Represents a node in a {@link Graph} object that Flo will display as a block.
  *
  * @author Andy Clement
  */
 @JsonIgnoreProperties(ignoreUnknown = true)
+@JsonInclude(Include.NON_EMPTY)
 public class Node {
 
-	public static final String METADATA_LABEL = "composedtask.label";
+	public static final String METADATA_LABEL = "label";
 
 	public String id;
 
@@ -88,13 +91,15 @@ public boolean isSync() {
 		return name.equals("SYNC");
 	}
 
+	@JsonIgnore
 	public void setLabel(String label) {
 		if (metadata == null) {
 			metadata = new HashMap<>();
 		}
 		metadata.put(METADATA_LABEL, label);
 	}
 
+	@JsonIgnore
 	public String getLabel() {
 		if (metadata == null) {
 			return null;

spring-cloud-dataflow-core/src/test/java/org/springframework/cloud/dataflow/core/dsl/TaskParserTests.java

@@ -784,8 +784,8 @@ public void validator() {
 		assertEquals(1,problems.size());
 		assertEquals(DSLMessage.TASK_VALIDATION_SECONDARY_SEQUENCES_MUST_BE_NAMED,problems.get(0).getMessage());
 		assertEquals(5,problems.get(0).getOffset());
-		assertEquals("158E:(pos 5): Secondary sequences must have labels or are unreachable",problems.get(0).toString());
-		assertEquals("158E:(pos 5): Secondary sequences must have labels or are unreachable\nappA;appB\n     ^\n",problems.get(0).toStringWithContext());
+		assertEquals("158E:(pos 5): secondary sequences must have labels or are unreachable",problems.get(0).toString());
+		assertEquals("158E:(pos 5): secondary sequences must have labels or are unreachable\nappA;appB\n     ^\n",problems.get(0).toStringWithContext());
 
 		validator.reset();
 		ctn = parse("appA;foo: appB");
@@ -799,8 +799,8 @@ public void validator() {
 		assertEquals(1,problems.size());
 		assertEquals(DSLMessage.TASK_VALIDATION_SECONDARY_SEQUENCES_MUST_BE_NAMED,problems.get(0).getMessage());
 		assertEquals(15,problems.get(0).getOffset());
-		assertEquals("158E:(pos 15): Secondary sequences must have labels or are unreachable",problems.get(0).toString());
-		assertEquals("158E:(pos 15): Secondary sequences must have labels or are unreachable\nappC\n^\n",problems.get(0).toStringWithContext());
+		assertEquals("158E:(pos 15): secondary sequences must have labels or are unreachable",problems.get(0).toString());
+		assertEquals("158E:(pos 15): secondary sequences must have labels or are unreachable\nappC\n^\n",problems.get(0).toStringWithContext());
 
 		validator.reset();
 		ctn = parse("<appA>",false);
@@ -809,7 +809,7 @@ public void validator() {
 		assertEquals(1,problems.size());
 		assertEquals(DSLMessage.TASK_VALIDATION_SPLIT_WITH_ONE_FLOW,problems.get(0).getMessage());
 		assertEquals(0,problems.get(0).getOffset());
-		assertEquals("167E:(pos 0): Unnecessary use of split construct when only one flow to execute in parallel",problems.get(0).toString());
+		assertEquals("167E:(pos 0): unnecessary use of split construct when only one flow to execute in parallel",problems.get(0).toString());
 	}
 
 	@Test

spring-cloud-dataflow-docs/src/test/java/org/springframework/cloud/dataflow/server/rest/documentation/ApiDocumentation.java

@@ -106,10 +106,13 @@ public void index() throws Exception {
 					linkWithRel("aggregate-counters").description("Provides the resource for dealing with aggregate counters"),
 					linkWithRel("aggregate-counters/counter").description("Handle a specific aggregate counter"),
 					linkWithRel("field-value-counters").description("Provides the resource for dealing with field-value-counters"),
-					linkWithRel("field-value-counters/counter").description("Handle a specific field-value-counter")),
+					linkWithRel("field-value-counters/counter").description("Handle a specific field-value-counter"),
+					linkWithRel("tools/parseTaskTextToGraph").description("Parse a task definition into a graph structure"),
+					linkWithRel("tools/convertTaskGraphToText").description("Convert a graph format into DSL text format")),
 				responseFields(
 					fieldWithPath("_links").description("Links to other resources"),
 					fieldWithPath("['"+Version.REVISION_KEY+"']").description("Incremented each time a change is implemented in this REST API")
+
 				)
 			));
 	}

spring-cloud-dataflow-rest-resource/src/main/java/org/springframework/cloud/dataflow/rest/resource/TaskToolsResource.java

@@ -0,0 +1,68 @@
+/*
+ * Copyright 2017 the original author or 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.springframework.cloud.dataflow.rest.resource;
+
+import java.util.List;
+import java.util.Map;
+
+import org.springframework.cloud.dataflow.core.dsl.graph.Graph;
+import org.springframework.hateoas.ResourceSupport;
+
+/**
+ * Represents a response from the tools endpoint. Depending on whether the request was to
+ * parse a DSL string into a graph or convert a graph to DSL, the different fields of the
+ * response will be filled in.
+ *
+ * @author Andy Clement
+ */
+public class TaskToolsResource extends ResourceSupport {
+
+	private Graph graph;
+
+	private String dsl;
+
+	// A list of errors, each entry is a map with keys for position and message text
+	private List<Map<String, Object>> errors;
+
+	public TaskToolsResource() {
+	}
+
+	public TaskToolsResource(Graph graph, List<Map<String, Object>> errors) {
+		this.graph = graph;
+		this.dsl = null;
+		this.errors = errors;
+	}
+
+	public TaskToolsResource(String dsl, List<Map<String,Object>> errors) {
+		this.graph = null;
+		this.dsl = dsl;
+		this.errors = errors;
+	}
+
+	public Graph getGraph() {
+		return graph;
+	}
+
+	public String getDsl() {
+		return dsl;
+	}
+
+	public List<Map<String,Object>> getErrors() {
+		return errors;
+	}
+
+}

spring-cloud-dataflow-server-core/src/main/java/org/springframework/cloud/dataflow/server/config/DataFlowControllerAutoConfiguration.java

@@ -58,6 +58,7 @@
 import org.springframework.cloud.dataflow.server.controller.StreamDeploymentController;
 import org.springframework.cloud.dataflow.server.controller.TaskDefinitionController;
 import org.springframework.cloud.dataflow.server.controller.TaskExecutionController;
+import org.springframework.cloud.dataflow.server.controller.ToolsController;
 import org.springframework.cloud.dataflow.server.controller.UiController;
 import org.springframework.cloud.dataflow.server.controller.security.LoginController;
 import org.springframework.cloud.dataflow.server.controller.security.SecurityController;
@@ -227,6 +228,11 @@ public CompletionController completionController(StreamCompletionProvider comple
 		return new CompletionController(completionProvider, taskCompletionProvider);
 	}
 
+	@Bean
+	public ToolsController toolsController() {
+		return new ToolsController();
+	}
+
 	@Bean
 	@ConditionalOnMissingBean(name = "appRegistryFJPFB")
 	public ForkJoinPoolFactoryBean appRegistryFJPFB() {