[JENKINS-31462] GitHub Enterprise Servers validation

pom.xml

@@ -39,7 +39,7 @@
         <dependency>
             <groupId>org.jenkins-ci.plugins</groupId>
             <artifactId>github-api</artifactId>
-            <version>1.69</version>
+            <version>1.71</version>
         </dependency>
         <dependency>
             <groupId>org.jenkins-ci.plugins</groupId>

src/main/java/org/jenkinsci/plugins/github_branch_source/Endpoint.java

@@ -24,12 +24,22 @@
 
 package org.jenkinsci.plugins.github_branch_source;
 
+import com.fasterxml.jackson.core.JsonParseException;
 import hudson.Extension;
 import hudson.Util;
 import hudson.model.AbstractDescribableImpl;
 import hudson.model.Descriptor;
 import hudson.util.FormValidation;
-import java.util.regex.Pattern;
+
+import java.io.IOException;
+import java.net.MalformedURLException;
+import java.net.URL;
+import java.util.logging.Logger;
+import java.util.logging.Level;
+
+import org.kohsuke.accmod.Restricted;
+import org.kohsuke.accmod.restrictions.NoExternalUse;
+import org.kohsuke.github.GitHub;
 import org.kohsuke.stapler.DataBoundConstructor;
 import org.kohsuke.stapler.QueryParameter;
 
@@ -89,29 +99,37 @@ public int hashCode() {
     @Extension
     public static class DesciptorImpl extends Descriptor<Endpoint> {
 
+        private static final Logger LOGGER = Logger.getLogger(DesciptorImpl.class.getName());
+
         @Override
         public String getDisplayName() {
             return "";
         }
 
-        public FormValidation doCheckApiUrl(@QueryParameter String value) {
-            if (Util.fixEmptyAndTrim(value) == null) {
-                return FormValidation.error("You must specify the API URI");
+        @Restricted(NoExternalUse.class)
+        public FormValidation doCheckApiUri(@QueryParameter String apiUri) {
+            if (Util.fixEmptyAndTrim(apiUri) == null) {
+                return FormValidation.warning("You must specify the API URL");
             }
-            Pattern enterprise = Pattern.compile("^https?://(([a-zA-Z]|[a-zA-Z][a-zA-Z0-9\\-]*[a-zA-Z0-9])\\.)*"
-                    + "([A-Za-z]|[A-Za-z][A-Za-z0-9\\-]*[A-Za-z0-9])/api/v3/?$");
-            if (!enterprise.matcher(value).matches()) {
-                return FormValidation.warning(
-                        "This does not look like a GitHub Enterprise API URI. Expecting something like "
-                                + "https://[hostname or ip]/api/v3/");
+            try {
+                URL api = new URL(apiUri);
+                GitHub github = GitHub.connectToEnterpriseAnonymously(api.toString());
+                github.checkApiUrlValidity();
+                return FormValidation.ok();
+            } catch (MalformedURLException mue) {
+                return FormValidation.error("This does not look like a GitHub Enterprise API URL");
+            } catch (JsonParseException jpe) {
+                return FormValidation.error("This does not look like a GitHub Enterprise API URL");
+            } catch (IOException e) {
+                LOGGER.log(Level.WARNING, e.getMessage());
+                return FormValidation.error("This does not look like a GitHub Enterprise API URL");
             }
-            // TODO validate connection
-            return FormValidation.ok();
         }
 
-        public FormValidation doCheckApiName(@QueryParameter String value) {
-            if (Util.fixEmptyAndTrim(value) == null) {
-                return FormValidation.warning("Specifying a name is recommended");
+        @Restricted(NoExternalUse.class)
+        public FormValidation doCheckName(@QueryParameter String name) {
+            if (Util.fixEmptyAndTrim(name) == null) {
+                return FormValidation.warning("You must specify the name");
             }
             return FormValidation.ok();
         }