David Bainbridge | 7526c45 | 2018-04-20 14:14:37 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2018-present Open Networking Foundation |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | package org.onosproject.drivers.netconf; |
| 17 | |
| 18 | import static org.slf4j.LoggerFactory.getLogger; |
| 19 | |
| 20 | import java.io.IOException; |
| 21 | import java.io.InputStream; |
| 22 | import java.nio.charset.StandardCharsets; |
| 23 | import java.util.HashMap; |
| 24 | import java.util.Map; |
| 25 | |
| 26 | import javax.xml.namespace.QName; |
| 27 | import javax.xml.parsers.DocumentBuilder; |
| 28 | import javax.xml.parsers.DocumentBuilderFactory; |
| 29 | import javax.xml.xpath.XPath; |
| 30 | import javax.xml.xpath.XPathConstants; |
| 31 | import javax.xml.xpath.XPathFactory; |
| 32 | |
| 33 | import org.apache.commons.io.IOUtils; |
| 34 | import org.onosproject.netconf.NetconfException; |
| 35 | import org.onosproject.netconf.NetconfSession; |
| 36 | import org.slf4j.Logger; |
| 37 | import org.w3c.dom.Document; |
| 38 | import org.w3c.dom.Node; |
| 39 | |
| 40 | import com.google.common.io.Resources; |
| 41 | |
| 42 | /** |
| 43 | * Manages templates and provides utilities to execute these templates against a |
| 44 | * NETCONF session. |
| 45 | */ |
| 46 | public final class TemplateManager { |
| 47 | private static final Logger log = getLogger(TemplateManager.class); |
| 48 | private final Map<String, String> templates = new HashMap<String, String>(); |
| 49 | private TemplateRequestDriver requestDriver; |
Ray Milkey | aab4ccf | 2018-05-03 09:11:25 -0700 | [diff] [blame^] | 50 | private static final Map<String, Object> EMPTY_TEMPLATE_CONTEXT = new HashMap<String, Object>(); |
David Bainbridge | 7526c45 | 2018-04-20 14:14:37 -0700 | [diff] [blame] | 51 | |
| 52 | /** |
| 53 | * Internal implementation of the request driver that implements a NETCONF |
| 54 | * driver. |
| 55 | */ |
| 56 | private class InternalRequestDriver implements TemplateRequestDriver { |
| 57 | @Override |
| 58 | public Object doRequest(NetconfSession session, String templateName, Map<String, Object> templateContext, |
| 59 | String baseXPath, QName returnType) throws NetconfException { |
| 60 | try { |
| 61 | String data = session.rpc(render(templates.get(templateName), templateContext)).get(); |
| 62 | InputStream resp = IOUtils.toInputStream(data, StandardCharsets.UTF_8); |
| 63 | DocumentBuilderFactory builderFactory = DocumentBuilderFactory.newInstance(); |
| 64 | DocumentBuilder builder = builderFactory.newDocumentBuilder(); |
| 65 | Document document = builder.parse(resp); |
| 66 | XPath xp = XPathFactory.newInstance().newXPath(); |
| 67 | return xp.evaluate(baseXPath, document, returnType); |
| 68 | } catch (Exception e) { |
| 69 | NetconfException ne = new NetconfException(e.getMessage(), e); |
| 70 | throw ne; |
| 71 | } |
| 72 | } |
| 73 | } |
| 74 | |
| 75 | /** |
| 76 | * Constructs a new template manager and loads the default templates. |
| 77 | */ |
| 78 | public TemplateManager() { |
| 79 | requestDriver = new InternalRequestDriver(); |
| 80 | } |
| 81 | |
| 82 | /** |
| 83 | * Sets the request driver for the template manager. |
| 84 | * |
| 85 | * @param driver |
| 86 | * the driver to use |
| 87 | */ |
| 88 | public void setRequestDriver(TemplateRequestDriver driver) { |
| 89 | requestDriver = driver; |
| 90 | } |
| 91 | |
| 92 | /** |
| 93 | * Loads the named templates into the template manager. |
| 94 | * |
| 95 | * @param reference |
| 96 | * the class reference from which to load resources |
| 97 | * @param pattern |
| 98 | * pattern to convert template name to resource path |
| 99 | * @param templateNames |
| 100 | * list of template to load |
| 101 | */ |
| 102 | public void load(Class<? extends Object> reference, String pattern, String... templateNames) { |
| 103 | for (String name : templateNames) { |
| 104 | String key = name; |
| 105 | String resource; |
| 106 | |
| 107 | // If the template name begins with a '/', then assume it is a full path |
| 108 | // specification |
| 109 | if (name.charAt(0) == '/') { |
| 110 | int start = name.lastIndexOf('/') + 1; |
| 111 | int end = name.lastIndexOf('.'); |
| 112 | if (end == -1) { |
| 113 | key = name.substring(start); |
| 114 | } else { |
| 115 | key = name.substring(start, end); |
| 116 | } |
| 117 | resource = name; |
| 118 | } else { |
| 119 | resource = String.format(pattern, name); |
| 120 | } |
| 121 | |
| 122 | log.error("LOAD TEMPLATE: '{}' as '{}' from '{}", name, key, resource); |
| 123 | |
| 124 | try { |
| 125 | templates.put(name, |
| 126 | Resources.toString(Resources.getResource(reference, resource), StandardCharsets.UTF_8)); |
| 127 | |
| 128 | } catch (IOException ioe) { |
| 129 | log.error("Unable to load NETCONF request template '{}' from '{}'", key, resource, ioe); |
| 130 | } |
| 131 | } |
| 132 | } |
| 133 | |
| 134 | /** |
| 135 | * Loads the named templates into the template manager using the default |
| 136 | * reference class and resource path pattern. |
| 137 | * |
| 138 | * @param templateMNames |
| 139 | * list of template to load |
| 140 | */ |
| 141 | public void load(String... templateMNames) { |
| 142 | load(this.getClass(), "/templates/requests/%s.j2", templateMNames); |
| 143 | } |
| 144 | |
| 145 | /** |
| 146 | * Loads the named templates into the template manager using the default |
| 147 | * reference class. |
| 148 | * |
| 149 | * @param pattern |
| 150 | * pattern to convert template name to resource path |
| 151 | * @param templateMNames |
| 152 | * list of template to load |
| 153 | */ |
| 154 | public void load(String pattern, String... templateMNames) { |
| 155 | load(this.getClass(), pattern, templateMNames); |
| 156 | } |
| 157 | |
| 158 | /** |
| 159 | * Returns the named template. |
| 160 | * |
| 161 | * @param templateName |
| 162 | * name of template to return |
| 163 | * @return template |
| 164 | */ |
| 165 | public String get(String templateName) { |
| 166 | return templates.get(templateName); |
| 167 | } |
| 168 | |
| 169 | /** |
| 170 | * Performs simple variable substitution into a string in likely the most |
| 171 | * inefficient way possible. |
| 172 | * |
| 173 | * @param template |
| 174 | * template into which to substitute variables |
| 175 | * @param context |
| 176 | * variable substitution map |
| 177 | * @return template rendered with variable substitution |
| 178 | */ |
| 179 | public String render(String template, Map<String, Object> context) { |
| 180 | if (context == null) { |
| 181 | return template; |
| 182 | } |
| 183 | |
| 184 | String temp = template; |
| 185 | for (Map.Entry<String, Object> e : context.entrySet()) { |
| 186 | temp = temp.replaceAll("\\{\\{ *" + e.getKey() + " *\\}\\}", e.getValue().toString()); |
| 187 | } |
| 188 | return temp; |
| 189 | } |
| 190 | |
| 191 | /** |
| 192 | * Executes the named NETCONF template against the specified session, returning |
| 193 | * the referenced XML node as the specified type. |
| 194 | * |
| 195 | * @param session |
| 196 | * NETCONF serssion |
| 197 | * @param templateName |
| 198 | * name of NETCONF request template to execute |
| 199 | * @param templateContext |
| 200 | * variable to values substitutions to be used against templates |
| 201 | * @param baseXPath |
| 202 | * XPath expression to specify the returned document node |
| 203 | * @param returnType |
| 204 | * expected return type of the referenced node |
| 205 | * @return XML document node referenced by the {@code baseXPath} |
| 206 | * @throws NetconfException |
| 207 | * if any IO, XPath, or NETCONF exception occurs |
| 208 | */ |
| 209 | public Object doRequest(NetconfSession session, String templateName, Map<String, Object> templateContext, |
| 210 | String baseXPath, QName returnType) throws NetconfException { |
| 211 | return requestDriver.doRequest(session, templateName, templateContext, baseXPath, returnType); |
| 212 | } |
| 213 | |
| 214 | /** |
| 215 | * Execute the named NETCONF template against the specified session returning |
| 216 | * the {@code /rpc-reply/data} section of the response document as a |
| 217 | * {@code Node}. |
| 218 | * |
| 219 | * @param session |
| 220 | * NETCONF session |
| 221 | * @param templateName |
| 222 | * name of NETCONF request template to execute |
| 223 | * @return XML document node that represents the NETCONF response data |
| 224 | * @throws NetconfException |
| 225 | * if any IO, XPath, or NETCONF exception occurs |
| 226 | */ |
| 227 | public Node doRequest(NetconfSession session, String templateName) throws NetconfException { |
| 228 | return (Node) doRequest(session, templateName, EMPTY_TEMPLATE_CONTEXT, "/rpc-reply/data", XPathConstants.NODE); |
| 229 | } |
| 230 | |
| 231 | /** |
| 232 | * Execute the named NETCONF template with the given template context against |
| 233 | * the specified session returning the {@code /rpc-reply/data} section of the |
| 234 | * response document as a {@code Node}. |
| 235 | * |
| 236 | * @param session |
| 237 | * NETCONF session |
| 238 | * @param templateName |
| 239 | * name of NETCONF request template to execute |
| 240 | * @param templateContext |
| 241 | * variables to substitute into the template |
| 242 | * @return XML document node that represents the NETCONF response data |
| 243 | * @throws NetconfException |
| 244 | * if any IO, XPath, or NETCONF exception occurs |
| 245 | */ |
| 246 | public Node doRequest(NetconfSession session, String templateName, Map<String, Object> templateContext) |
| 247 | throws NetconfException { |
| 248 | return (Node) doRequest(session, templateName, templateContext, "/rpc-reply/data", XPathConstants.NODE); |
| 249 | } |
| 250 | } |