Merge pull request #178 from pdowler/master

cadc-vosi: optional startupMode config
opencadc · Mar 26, 2024 · 1f5eff3 · 1f5eff3
2 parents 5dcab89 + 48dcef5
commit 1f5eff3
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diff --git a/cadc-vosi/README.md b/cadc-vosi/README.md
@@ -8,19 +8,59 @@ cadc-tap-schema</a> library.
 In addition to the normal VOSI API, the VOSI-availability component supports optional
 changing of the service state. Supported states: ReadWrite (normal), ReadOnly, and Offline.
 
+Set state example:
+```
+curl --cert <cert file> -d state=ReadOnly https://example.net/srv/availability
+```
+Get example:
+```
+curl https://example.net/srv/availability
+```
+
 ## cadc-vosi.properties
 This config file (optional) allows deployers to specify users that are allowed to
 change the service state via HTTP POST to the `/availability` endpoint.
 ```properties
 user = {X509 distinguished name}
 user = ...
+
+# optional mode at startup: Offline, ReadOnly, ReadWrite (default)
+startupMode = ReadWrite|ReadOnly|Offline
 ```
+
 For the X509 distinguished name, the availability endpoint can successfully authorise the 
 user even when the associated AAI system is unavailable, so this mechanism is more robust
 as it does not depend on any other functioning component.
 
+If an optional _startupMode_ is configured, the availability servlet will create the service-specific
+AvailabilityPlugin and call `setState`. The behaviour is completely in the control of the service
+and how it implements the plugin.
+
 ## TODO
 - rewrite the AvailabilityServlet as a RestAction based on the `cadc-rest` library
 - add ability to configure users and groups consistent with the `cadc-log` library
 - remove the old CapabilitiesServlet
 - developer documentation (how to include in web.xml)
+
+## temporary developer documentation
+The following (or something like it) is needed in the `web.xml` deployment descriptor to add 
+an /avaailability endpoint to a service:
+```xml
+<!-- VOSI availability -->
+  <servlet>
+    <servlet-name>AvailabilityServlet</servlet-name>
+    <servlet-class>ca.nrc.cadc.vosi.AvailabilityServlet</servlet-class>
+    <init-param>
+      <param-name>ca.nrc.cadc.vosi.AvailabilityPlugin</param-name>
+      <param-value>fully.qualified.classname.for.AvailabilityPluginImpl</param-value>
+    </init-param>
+    <load-on-startup>2</load-on-startup>
+  </servlet>
+  <servlet-mapping>
+    <servlet-name>AvailabilityServlet</servlet-name>
+    <url-pattern>/availability</url-pattern>
+  </servlet-mapping>
+```
+Especially if using the _startupMode_, putting this servlet early in the load sequence (2 above, before
+service specific endpoints and init) will ensure that the startup mode is set before other init happens.
+
diff --git a/cadc-vosi/build.gradle b/cadc-vosi/build.gradle
@@ -16,7 +16,7 @@ sourceCompatibility = 1.8
 
 group = 'org.opencadc'
 
-version = '1.4.5'
+version = '1.4.6'
 
 description = 'OpenCADC VOSI server library'
 def git_url = 'https://github.com/opencadc/reg'
@@ -27,7 +27,7 @@ dependencies {
     compile 'javax.servlet:javax.servlet-api:[3.1.0,)'
 
     compile 'org.opencadc:cadc-util:[1.6,)'
-    compile 'org.opencadc:cadc-rest:[1.3.6,)'
+    compile 'org.opencadc:cadc-rest:[1.3.20,)'
     compile 'org.opencadc:cadc-registry:[1.3.5,)'
 
     runtime 'org.jdom:saxpath:1.0-FCS'

diff --git a/cadc-vosi/src/main/java/ca/nrc/cadc/vosi/AvailabilityServlet.java b/cadc-vosi/src/main/java/ca/nrc/cadc/vosi/AvailabilityServlet.java
@@ -74,10 +74,12 @@
 import ca.nrc.cadc.log.ServletLogInfo;
 import ca.nrc.cadc.log.WebServiceLogInfo;
 import ca.nrc.cadc.net.NetUtil;
+import ca.nrc.cadc.util.InvalidConfigException;
 import ca.nrc.cadc.util.MultiValuedProperties;
 import ca.nrc.cadc.util.PropertiesReader;
 import ca.nrc.cadc.util.StringUtil;
 import java.io.IOException;
+import java.lang.reflect.InvocationTargetException;
 import java.security.Principal;
 import java.util.HashSet;
 import java.util.List;
@@ -103,6 +105,7 @@ public class AvailabilityServlet extends HttpServlet {
     private static final long serialVersionUID = 201003131300L;
 
     private static final String AVAILABILITY_PROPERTIES = "cadc-vosi.properties";
+    private static final String MODE_KEY = "startupMode";
     private static final String USERS_PROPERTY = "user";
 
     private String pluginClassName;
@@ -115,6 +118,27 @@ public void init(ServletConfig config)
         this.appName = config.getServletContext().getContextPath().substring(1).replaceAll("/", "-"); 
         this.pluginClassName = config.getInitParameter(AvailabilityPlugin.class.getName());
         log.info("application: " + appName + " plugin impl: " + pluginClassName);
+
+        MultiValuedProperties mvp = getAvailabilityProperties();
+        String startupMode = mvp.getFirstPropertyValue(MODE_KEY);
+        if (startupMode != null) {
+            AvailabilityPlugin ap = loadPlugin();
+            ap.setState(startupMode);
+        }
+    }
+
+    private AvailabilityPlugin loadPlugin() throws InvalidConfigException {
+        try {
+            Class wsClass = Class.forName(pluginClassName);
+            AvailabilityPlugin ap = (AvailabilityPlugin) wsClass.getConstructor().newInstance();
+            ap.setAppName(appName);
+            log.debug("loaded: " + wsClass);
+            return ap;
+        } catch (ClassNotFoundException | IllegalAccessException | IllegalArgumentException 
+                | InstantiationException | NoSuchMethodException | SecurityException 
+                | InvocationTargetException ex) {
+            throw new InvalidConfigException("failed to load AvailabilityPlugin: " + pluginClassName, ex);
+        }
     }
 
     @Override
@@ -128,9 +152,7 @@ protected void doGet(HttpServletRequest request, HttpServletResponse response)
             logInfo.setSubject(subject);
             log.info(logInfo.start());
 
-            Class wsClass = Class.forName(pluginClassName);
-            AvailabilityPlugin ap = (AvailabilityPlugin) wsClass.newInstance();
-            ap.setAppName(appName);
+            AvailabilityPlugin ap = loadPlugin();
 
             String detail = request.getParameter("detail");
             if (detail != null && detail.equals("min")) {
@@ -174,9 +196,7 @@ protected void doPost(HttpServletRequest request, HttpServletResponse response)
             logInfo.setSubject(subject);
             log.info(logInfo.start());
 
-            Class wsClass = Class.forName(pluginClassName);
-            AvailabilityPlugin ap = (AvailabilityPlugin) wsClass.newInstance();
-            ap.setAppName(appName);
+            AvailabilityPlugin ap = loadPlugin();
 
             IdentityManager im = AuthenticationUtil.getIdentityManager();
             String caller = im.toDisplayString(subject);

diff --git a/cadc-vosi/src/main/java/ca/nrc/cadc/vosi/CapInitAction.java b/cadc-vosi/src/main/java/ca/nrc/cadc/vosi/CapInitAction.java
@@ -70,6 +70,7 @@
 import ca.nrc.cadc.reg.Capabilities;
 import ca.nrc.cadc.reg.CapabilitiesReader;
 import ca.nrc.cadc.rest.InitAction;
+import ca.nrc.cadc.rest.Version;
 import ca.nrc.cadc.util.StringUtil;
 
 import java.io.StringReader;
@@ -189,7 +190,7 @@ public void doInit() {
         }
 
         try {
-            String version = findLibraryVersion(CapInitAction.class);
+            Version version = getLibraryVersion(CapInitAction.class);
 
             jndiKey = componentID + ".version";
             try {
@@ -198,46 +199,10 @@ public void doInit() {
             } catch (NamingException e) {
                 log.debug("no previously bound value, continuting");
             }
-            initContext.bind(jndiKey, version);
+            initContext.bind(jndiKey, version.getMajorMinor());
             log.info("doInit: version=" + version + " stored via JNDI: " + jndiKey);
         } catch (Exception ex) {
             throw new IllegalArgumentException("CONFIG: failed to set version flag", ex);
         }
     }
-
-    // TODO: move this code up to cadc-rest or cadc-util
-    private String findLibraryVersion(Class probe) {
-        String ret = "no-version-found";
-        String rname = probe.getSimpleName() + ".class";
-        try {
-
-            URL resURL = probe.getResource(rname);
-            log.debug("library URL: " + resURL);
-            // assume assume maven-central naming conventions for jar
-            // jar:file:/path/to/{library}-{ver}.jar!/package/subpackage/{rname}
-            if (resURL != null) {
-                String[] parts = resURL.toExternalForm().split("[:!]");
-                int i = 0;
-                for (String p : parts) {
-                    if (p.endsWith(".jar")) {
-                        int s = p.lastIndexOf('/');
-                        String ver = p.substring(s + 1); // {library}-{ver}.jar
-                        ver = ver.replace(".jar", "");   // {library}-{ver}
-
-                        // extract {major}.{minor} only
-                        String[] mmp = ver.split("\\.");
-                        if (mmp.length > 2) {
-                            ret = mmp[0] + "." + mmp[1];
-                        } else {
-                            ret = ver;
-                        }
-                    }
-                }
-            }
-        } catch (Exception ex) {
-            log.error("failed to find version for " + rname + " from classpath", ex);
-        }
-
-        return ret;
-    }
 }