Issue #59: Display the connector variables

src/main/java/org/sentrysoftware/maven/metricshub/connector/producer/ConnectorJsonNodeReader.java

@@ -28,15 +28,18 @@
 import com.fasterxml.jackson.databind.JsonNode;
 import com.fasterxml.jackson.databind.node.ArrayNode;
 import java.util.Collections;
+import java.util.HashMap;
 import java.util.HashSet;
 import java.util.List;
+import java.util.Map;
 import java.util.Optional;
 import java.util.Set;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
 import lombok.AllArgsConstructor;
+import org.sentrysoftware.maven.metricshub.connector.producer.model.common.ConnectorDefaultVariable;
 import org.sentrysoftware.maven.metricshub.connector.producer.model.common.TechnologyType;
 
 /**
@@ -605,4 +608,56 @@ public List<String> getTags() {
 		}
 		return Collections.emptyList();
 	}
+
+	/**
+	 * Retrieves all variable names from the connector template.
+	 * Variables are expected to be in the format: ${var::variableName}.
+	 *
+	 * @return a set of unique variable names found within the connector template.
+	 */
+	public Set<String> getVariablesNames() {
+		final String stringConnector = connector.toString();
+		final String variableRegex = "\\$\\{var::(.*?)\\}";
+		final Set<String> variables = new HashSet<>();
+
+		final Pattern pattern = Pattern.compile(variableRegex);
+		final Matcher matcher = pattern.matcher(stringConnector);
+
+		while (matcher.find()) {
+			variables.add(matcher.group(1));
+		}
+		return variables;
+	}
+
+	/**
+	 * Retrieves the default connector variables declared in the connector.
+	 * These variables include their descriptions and default values.
+	 *
+	 * @return a map of variable names to their corresponding {@link ConnectorDefaultVariable} objects,
+	 *         each containing a description and a default value. Returns an empty map if no variables are declared.
+	 */
+	public Map<String, ConnectorDefaultVariable> getDefaultVariables() {
+		final JsonNode variablesNode = getConnectorSection().map(node -> node.get("variables")).orElse(null);
+
+		final Map<String, ConnectorDefaultVariable> defaultVariables = new HashMap<>();
+		if (nonNull(variablesNode)) {
+			variablesNode
+				.fields()
+				.forEachRemaining(entry -> {
+					final String variableName = entry.getKey();
+					final JsonNode variableValue = entry.getValue();
+
+					final String description = variableValue.get("description").asText();
+					final String defaultValue = variableValue.get("defaultValue").asText();
+
+					// Create a ConnectorDefaultVariable object and put it into the map
+					final ConnectorDefaultVariable connectorDefaultVariable = new ConnectorDefaultVariable(
+						description,
+						defaultValue
+					);
+					defaultVariables.put(variableName, connectorDefaultVariable);
+				});
+		}
+		return defaultVariables;
+	}
 }

src/main/java/org/sentrysoftware/maven/metricshub/connector/producer/ConnectorPageProducer.java

@@ -36,6 +36,7 @@
 import lombok.Builder;
 import org.apache.maven.doxia.sink.Sink;
 import org.apache.maven.plugin.logging.Log;
+import org.sentrysoftware.maven.metricshub.connector.producer.model.common.ConnectorDefaultVariable;
 import org.sentrysoftware.maven.metricshub.connector.producer.model.common.OpenTelemetryHardwareType;
 import org.sentrysoftware.maven.metricshub.connector.producer.model.common.OsType;
 import org.sentrysoftware.maven.metricshub.connector.producer.model.common.TechnologyType;
@@ -187,6 +188,38 @@ public void produce(
 		sink.bold_();
 		sink.paragraph_();
 
+		// Displaying connector variables list
+		final Set<String> connectorVariables = connectorJsonNodeReader.getVariablesNames();
+		final Map<String, ConnectorDefaultVariable> connectorDefaultVariables =
+			connectorJsonNodeReader.getDefaultVariables();
+		if (!connectorVariables.isEmpty()) {
+			sink.paragraph();
+			sink.text("Variables:");
+			sink.list();
+			for (final String variable : connectorVariables) {
+				sink.listItem();
+				sink.rawText(String.format("<code>%s</code>", variable));
+				sink.list();
+				sink.listItem();
+				final ConnectorDefaultVariable defaultVariable = connectorDefaultVariables.getOrDefault(
+					variable,
+					new ConnectorDefaultVariable("", "No default value.")
+				);
+				sink.text("description: ");
+				sink.text(defaultVariable.getDescription());
+				sink.listItem_();
+
+				sink.listItem();
+				sink.text("default value: ");
+				sink.text(defaultVariable.getDefaultValue());
+				sink.listItem_();
+				sink.list_();
+				sink.listItem_();
+			}
+			sink.list_();
+			sink.paragraph_();
+		}
+
 		// Sudo Commands?
 		final List<String> sudoCommands = connectorJsonNodeReader.getSudoCommands();
 		produceSudoCommandsContent(sink, sudoCommands);
@@ -212,7 +245,7 @@ public void produce(
 		sink.section2_();
 
 		// MetricsHub Example
-		produceMetricsHubExamplesContent(sink, appliesTo, technologies, sudoCommands);
+		produceMetricsHubExamplesContent(sink, appliesTo, technologies, sudoCommands, connectorVariables);
 
 		// Detection criteria
 		sink.section2();
@@ -388,7 +421,8 @@ private void produceMetricsHubExamplesContent(
 		final Sink sink,
 		final List<String> osTypes,
 		final Set<TechnologyType> technologies,
-		final List<String> sudoCommands
+		final List<String> sudoCommands,
+		final Set<String> connectorVariables
 	) {
 		sink.section2();
 		sink.sectionTitle2();
@@ -482,6 +516,12 @@ private void produceMetricsHubExamplesContent(
 			appendYamlUsernameAndPassword(yamlBuilder);
 		}
 
+		// Connector variable
+		if (connectorVariables != null && !connectorVariables.isEmpty()) {
+			yamlBuilder.append("        variables:\n");
+			yamlBuilder.append(String.format("          %s: %s", connectorVariables.iterator().next(), "<VALUE>"));
+			yamlBuilder.append(" # Replace with desired value.\n");
+		}
 		// CLI
 		sink.section3();
 		sink.sectionTitle3();

src/main/java/org/sentrysoftware/maven/metricshub/connector/producer/model/common/ConnectorDefaultVariable.java

@@ -0,0 +1,42 @@
+package org.sentrysoftware.maven.metricshub.connector.producer.model.common;
+
+import lombok.AllArgsConstructor;
+import lombok.Builder;
+import lombok.Data;
+import lombok.NoArgsConstructor;
+
+/*-
+ * ╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲
+ * MetricsHub Connector Maven Plugin
+ * ჻჻჻჻჻჻
+ * Copyright (C) 2023 Sentry Software
+ * ჻჻჻჻჻჻
+ * 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.
+ * ╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱
+ */
+
+@NoArgsConstructor
+@AllArgsConstructor
+@Data
+@Builder
+public class ConnectorDefaultVariable {
+
+	/**
+	 * The default connector variable description.
+	 */
+	private String description;
+	/**
+	 * The default connector variable default value.
+	 */
+	private String defaultValue;
+}