Add velocity engine template service

Change-Id: Idde39b587b41328e5a5e2e32ab32c29cd27d4855
Issue-ID: CCSDK-941
Signed-off-by: Muthuramalingam, Brinda Santh <bs2796@att.com>

6 files changed, 243 insertions, 1 deletions

diff --git a/components/core/pom.xml b/components/core/pom.xml
index f33146b6a..03d46f493 100644
--- a/components/core/pom.xml
+++ b/components/core/pom.xml
@@ -52,6 +52,10 @@
             <groupId>org.yaml</groupId>
             <artifactId>snakeyaml</artifactId>
         </dependency>
+        <dependency>
+            <groupId>org.apache.velocity</groupId>
+            <artifactId>velocity</artifactId>
+        </dependency>
         <!--Testing dependencies-->
         <dependency>
             <groupId>org.jetbrains.kotlin</groupId>
diff --git a/components/core/src/main/kotlin/org/onap/ccsdk/apps/controllerblueprints/core/service/BluePrintTemplateService.kt b/components/core/src/main/kotlin/org/onap/ccsdk/apps/controllerblueprints/core/service/BluePrintTemplateService.kt
new file mode 100644
index 000000000..d175fddea
--- /dev/null
+++ b/components/core/src/main/kotlin/org/onap/ccsdk/apps/controllerblueprints/core/service/BluePrintTemplateService.kt
@@ -0,0 +1,94 @@
+/*
+ * Copyright © 2017-2018 AT&T Intellectual Property.
+ *
+ * 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.onap.ccsdk.apps.controllerblueprints.core.service
+
+import com.fasterxml.jackson.core.io.CharTypes
+import com.fasterxml.jackson.databind.JsonNode
+import com.fasterxml.jackson.databind.ObjectMapper
+import com.fasterxml.jackson.databind.node.JsonNodeFactory
+import com.fasterxml.jackson.databind.node.TextNode
+import org.apache.commons.lang3.BooleanUtils
+import org.apache.commons.lang3.StringUtils
+import org.apache.velocity.VelocityContext
+import org.apache.velocity.app.Velocity
+import org.onap.ccsdk.apps.controllerblueprints.core.BluePrintProcessorException
+import org.onap.ccsdk.apps.controllerblueprints.core.utils.JacksonUtils
+import java.io.StringWriter
+
+open class BluePrintTemplateService {
+
+    companion object {
+
+        /**
+         * Generate Content from Velocity Template and JSON Content.
+         */
+        fun generateContent(template: String, json: String,
+                            ignoreJsonNull: Boolean = false,
+                            additionalContext: MutableMap<String, Any> = hashMapOf()): String {
+            Velocity.init()
+            val mapper = ObjectMapper()
+            val nodeFactory = BluePrintJsonNodeFactory()
+            mapper.setNodeFactory(nodeFactory)
+
+            val jsonNode = mapper.readValue<JsonNode>(json, JsonNode::class.java)
+                    ?: throw BluePrintProcessorException("couldn't get json node from json")
+
+            if (ignoreJsonNull)
+                JacksonUtils.removeJsonNullNode(jsonNode)
+
+            val velocityContext = VelocityContext()
+            velocityContext.put("StringUtils", StringUtils::class.java)
+            velocityContext.put("BooleanUtils", BooleanUtils::class.java)
+            /**
+             * Add the Custom Velocity Context API
+             */
+            additionalContext.forEach { name, value -> velocityContext.put(name, value) }
+            /**
+             * Add the JSON Data to the context
+             */
+            jsonNode.fields().forEach { entry ->
+                velocityContext.put(entry.key, entry.value)
+            }
+
+            val stringWriter = StringWriter()
+            Velocity.evaluate(velocityContext, stringWriter, "TemplateData", template)
+            stringWriter.flush()
+            return stringWriter.toString()
+        }
+    }
+}
+
+/**
+ * Customise JsonNodeFactory adn TextNode, Since it introduces quotes for string data.
+ */
+open class BluePrintJsonNodeFactory : JsonNodeFactory() {
+    override fun textNode(text: String): TextNode {
+        return BluePrintTextNode(text)
+    }
+}
+
+open class BluePrintTextNode(v: String) : TextNode(v) {
+    override fun toString(): String {
+        var len = this._value.length
+        len = len + 2 + (len shr 4)
+        val sb = StringBuilder(len)
+        CharTypes.appendQuoted(sb, this._value)
+        return sb.toString()
+    }
+
+}
+
diff --git a/components/core/src/main/kotlin/org/onap/ccsdk/apps/controllerblueprints/core/utils/JacksonUtils.kt b/components/core/src/main/kotlin/org/onap/ccsdk/apps/controllerblueprints/core/utils/JacksonUtils.kt
index 58a820791..6321a8385 100644
--- a/components/core/src/main/kotlin/org/onap/ccsdk/apps/controllerblueprints/core/utils/JacksonUtils.kt
+++ b/components/core/src/main/kotlin/org/onap/ccsdk/apps/controllerblueprints/core/utils/JacksonUtils.kt
@@ -21,10 +21,10 @@ import com.att.eelf.configuration.EELFManager
 import com.fasterxml.jackson.annotation.JsonInclude

 import com.fasterxml.jackson.core.type.TypeReference

 import com.fasterxml.jackson.databind.JsonNode

+import com.fasterxml.jackson.databind.SerializationFeature

 import com.fasterxml.jackson.databind.node.ArrayNode

 import com.fasterxml.jackson.databind.node.NullNode

 import com.fasterxml.jackson.databind.node.ObjectNode

-import com.fasterxml.jackson.databind.SerializationFeature

 import com.fasterxml.jackson.module.kotlin.jacksonObjectMapper

 import kotlinx.coroutines.Dispatchers

 import kotlinx.coroutines.async

@@ -56,6 +56,18 @@ class JacksonUtils {
             return jacksonObjectMapper().treeToValue(node, valueType)

         }

 

+        fun removeJsonNullNode(node: JsonNode) {

+            val it = node.iterator()

+            while (it.hasNext()) {

+                val child = it.next()

+                if (child.isNull) {

+                    it.remove()

+                } else {

+                    removeJsonNullNode(child)

+                }

+            }

+        }

+

         fun getContent(fileName: String): String = runBlocking {

             async {

                 try {

diff --git a/components/core/src/test/kotlin/org/onap/ccsdk/apps/controllerblueprints/core/service/BluePrintTemplateServiceTest.kt b/components/core/src/test/kotlin/org/onap/ccsdk/apps/controllerblueprints/core/service/BluePrintTemplateServiceTest.kt
new file mode 100644
index 000000000..663a3751a
--- /dev/null
+++ b/components/core/src/test/kotlin/org/onap/ccsdk/apps/controllerblueprints/core/service/BluePrintTemplateServiceTest.kt
@@ -0,0 +1,35 @@
+/*
+ * Copyright © 2017-2018 AT&T Intellectual Property.
+ *
+ * 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.onap.ccsdk.apps.controllerblueprints.core.service
+
+import org.junit.Test
+import org.onap.ccsdk.apps.controllerblueprints.core.utils.JacksonUtils
+import kotlin.test.assertNotNull
+
+class BluePrintTemplateServiceTest {
+
+    @Test
+    fun testGenerateContent() {
+
+        val template = JacksonUtils.getClassPathFileContent("templates/base-config-template.vtl")
+        val json = JacksonUtils.getClassPathFileContent("templates/base-config-data.json")
+
+        val content = BluePrintTemplateService.generateContent(template, json)
+        assertNotNull(content, "failed to generate content for velocity template")
+
+    }
+}
\ No newline at end of file
diff --git a/components/core/src/test/resources/templates/base-config-data.json b/components/core/src/test/resources/templates/base-config-data.json
new file mode 100755
index 000000000..2acc6fcdd
--- /dev/null
+++ b/components/core/src/test/resources/templates/base-config-data.json
@@ -0,0 +1,36 @@
+{
+	"node0_hostname": "sdnc-host",
+	"node0_backup_router_address": "2001:1890:1253::192:168:100:1",
+	"servers": [
+		"Server1",
+		"Server2",
+		"Server3"
+	],
+	"tacplus-servers": [
+		{
+			"tacplus-server-name": "tacplus-server-name1",
+			"tacplus-server-source-address": "enc-dsdsasa1"
+		},
+		{
+			"tacplus-server-name": "tacplus-server-name2",
+			"tacplus-server-source-address": "enc-dsdsasa2"
+		}
+	],
+	"classes": [
+		{
+			"name": "superuser-class",
+			"idle-timeout": 5,
+			"permissions": "all"
+		},
+		{
+			"name": "tacacs-adv-class",
+			"idle-timeout": 5
+		},
+		{
+			"name": "tacacs-base-class",
+			"idle-timeout": 5
+		}
+	],
+	"system-password": "teamops-system-password",
+	"root-password": "teamops-root-password"
+}
diff --git a/components/core/src/test/resources/templates/base-config-template.vtl b/components/core/src/test/resources/templates/base-config-template.vtl
new file mode 100755
index 000000000..f7b1269b3
--- /dev/null
+++ b/components/core/src/test/resources/templates/base-config-template.vtl
@@ -0,0 +1,61 @@
+<configuration xmlns="http://xml.juniper.net/xnm/1.1/xnm"
+xmlns:a="http://xml.juniper.net/junos/15.1X49/junos">
+	<version>15.1X49-D50.3</version>	
+	<groups>
+		<name>node0</name>
+		<system>
+		#foreach($server in ${servers})
+			<server-host-name>$StringUtils.upperCase("$server")</server-host-name>
+		#end
+		</system>
+		<system>
+			<host-name>${node0_hostname}</host-name>
+			<backup-router>
+				<address>${node0_backup_router_address}</address>
+				<destination>$node0_backup_router_address</destination>
+			</backup-router>
+			#foreach($tacplus-server in ${tacplus-servers})
+			<tacplus-server>
+				<name>$tacplus-server.tacplus-server-name</name>
+				<source-address>$tacplus-server.tacplus-server-source-address</source-address>
+			</tacplus-server>
+			#end
+			<login>
+				<message>ONAP information assets</message>
+				#foreach($class in ${classes})
+				<class>
+					<name>$class.name</name>
+					<idle-timeout>$class.idle-timeout</idle-timeout>
+					#if ($class.permissions)
+					<permissions>$class.permissions</permissions>
+					#end
+				</class>
+				#end	
+				<user>
+					<name>readonly</name>
+					<full-name>Read Only Account Access</full-name>
+					<uid>1001</uid>
+					<class>tacacs-base-class</class>
+				</user>
+				<user>
+					<name>readwrite</name>
+					<full-name>Read - Write Account Access</full-name>
+					<uid>1002</uid>
+					<class>tacacs-adv-class</class>
+					<authentication>
+						<encrypted-password>${system-password}</encrypted-password>
+					</authentication>
+				</user>
+				<user>
+					<name>readwrite</name>
+					<full-name>Emergency Access Only</full-name>
+					<uid>1000</uid>
+					<class>superuser-class</class>
+					<authentication>
+						<encrypted-password>${root-password}</encrypted-password>
+					</authentication>
+				</user>
+			</login>
+		</system>		
+	</groups>	
+</configuration>
\ No newline at end of file