Merge pull request #632 from ryandens/ryandens/github-customizer

Add GitHubCustomizer

Author: gsmet

docs/modules/ROOT/pages/developer-reference.adoc

@@ -370,6 +370,25 @@ You can use the constants present in `io.quarkiverse.githubapp.Credentials` for
 That is all you need to do:
 Quarkus GitHub App will then automatically use the values provided by the `CredentialsProvider` for the private key and the webhook secret.
 
+== Customizing the GitHub clients
+
+You can customize the GitHub clients initialized by Quarkus GitHub App
+by creating a CDI bean implementing `io.quarkiverse.githubapp.GitHubCustomizer`.
+
+For instance:
+
+[source,java]
+----
+@Singleton
+public class MyGitHubCustomizer implements GitHubCustomizer {
+
+    @Override
+    public void customize(GitHubBuilder builder) {
+       // call methods of the builder
+    }
+}
+----
+
 == Architecture Overview
 
 image::architecture.png[Architecture]

runtime/src/main/java/io/quarkiverse/githubapp/GitHubCustomizer.java

@@ -0,0 +1,24 @@
+package io.quarkiverse.githubapp;
+
+import org.kohsuke.github.GitHubBuilder;
+
+/**
+ * Provide a CDI bean implementing this interface to customize {@link GitHubBuilder} used to create the
+ * {@link org.kohsuke.github.GitHub} instances.
+ */
+public interface GitHubCustomizer {
+
+    /**
+     * Customize the {@link GitHubBuilder} with various options.
+     * <p>
+     * Note that customizations that use {@link GitHubBuilder#withAppInstallationToken(String)} and
+     * {@link GitHubBuilder#withEndpoint(String)} are eventually overridden by the
+     * {@link io.quarkiverse.githubapp.runtime.github.GitHubService}. Installation tokens are created and cached by the service.
+     * <p>
+     * To specify a custom endpoint, use configuration properties {@code quarkus.github-app.instance-endpoint} or
+     * {@code quarkus.github-app.rest-api-endpoint}.
+     *
+     * @param builder to customize
+     */
+    void customize(GitHubBuilder builder);
+}

runtime/src/main/java/io/quarkiverse/githubapp/runtime/github/GitHubService.java

@@ -9,6 +9,7 @@
 import java.util.concurrent.TimeUnit;
 
 import jakarta.enterprise.context.ApplicationScoped;
+import jakarta.enterprise.inject.Instance;
 import jakarta.inject.Inject;
 
 import org.kohsuke.github.GHAppInstallationToken;
@@ -23,6 +24,7 @@
 import com.github.benmanes.caffeine.cache.LoadingCache;
 
 import io.quarkiverse.githubapp.GitHubClientProvider;
+import io.quarkiverse.githubapp.GitHubCustomizer;
 import io.quarkiverse.githubapp.runtime.config.CheckedConfigProvider;
 import io.quarkiverse.githubapp.runtime.signing.JwtTokenCreator;
 import io.smallrye.graphql.client.dynamic.api.DynamicGraphQLClient;
@@ -33,16 +35,26 @@ public class GitHubService implements GitHubClientProvider {
 
     private static final String AUTHORIZATION_HEADER = "Authorization";
     private static final String AUTHORIZATION_HEADER_BEARER = "Bearer %s";
+    private static final GitHubCustomizer NOOP_GITHUB_CUSTOMIZER = new GitHubCustomizer() {
+
+        @Override
+        public void customize(GitHubBuilder builder) {
+        }
+    };
 
     private final CheckedConfigProvider checkedConfigProvider;
 
     private final LoadingCache<Long, CachedInstallationToken> installationTokenCache;
 
     private final JwtTokenCreator jwtTokenCreator;
     private final GitHubConnector gitHubConnector;
+    private final GitHubCustomizer githubCustomizer;
 
     @Inject
-    public GitHubService(CheckedConfigProvider checkedConfigProvider, JwtTokenCreator jwtTokenCreator) {
+    public GitHubService(
+            CheckedConfigProvider checkedConfigProvider,
+            JwtTokenCreator jwtTokenCreator,
+            Instance<GitHubCustomizer> gitHubCustomizer) {
         this.checkedConfigProvider = checkedConfigProvider;
         this.jwtTokenCreator = jwtTokenCreator;
         this.installationTokenCache = Caffeine.newBuilder()
@@ -74,6 +86,8 @@ public long expireAfterRead(Long installationId, CachedInstallationToken cachedI
                 .build(new CreateInstallationToken());
         this.gitHubConnector = new HttpClientGitHubConnector(
                 HttpClient.newBuilder().version(Version.HTTP_1_1).followRedirects(HttpClient.Redirect.NEVER).build());
+        // if the customizer is not resolvable, we use a no-op customizer
+        githubCustomizer = gitHubCustomizer.isResolvable() ? gitHubCustomizer.get() : NOOP_GITHUB_CUSTOMIZER;
     }
 
     @Override
@@ -126,7 +140,11 @@ private GitHub createInstallationClient(long installationId) throws IOException
         CachedInstallationToken installationToken = installationTokenCache.get(installationId);
 
         final GitHubBuilder gitHubBuilder = new GitHubBuilder()
-                .withConnector(gitHubConnector)
+                .withConnector(gitHubConnector);
+        // apply customizations
+        githubCustomizer.customize(gitHubBuilder);
+        // configure mandatory defaults
+        gitHubBuilder
                 .withAppInstallationToken(installationToken.getToken())
                 .withEndpoint(checkedConfigProvider.restApiEndpoint());
 
@@ -194,7 +212,11 @@ private GitHub createApplicationGitHub() {
 
         try {
             final GitHubBuilder gitHubBuilder = new GitHubBuilder()
-                    .withConnector(gitHubConnector)
+                    .withConnector(gitHubConnector);
+            // apply customizations
+            githubCustomizer.customize(gitHubBuilder);
+            // configure mandatory defaults
+            gitHubBuilder
                     .withJwtToken(jwtToken)
                     .withEndpoint(checkedConfigProvider.restApiEndpoint());