From 175e851cb746550379fce0686b11752f4df04070 Mon Sep 17 00:00:00 2001
From: Scott Frederick <sfrederick@pivotal.io>
Date: Mon, 18 May 2020 16:23:30 -0500
Subject: [PATCH] Add ClientNotConfiguredFailureAnalyzer

---
 .../ClientNotConfiguredFailureAnalyzer.java   | 70 +++++++++++++++++++
 .../main/resources/META-INF/spring.factories  |  3 +
 2 files changed, 73 insertions(+)
 create mode 100644 spring-credhub-starter/src/main/java/org/springframework/credhub/diagnostics/ClientNotConfiguredFailureAnalyzer.java

diff --git a/spring-credhub-starter/src/main/java/org/springframework/credhub/diagnostics/ClientNotConfiguredFailureAnalyzer.java b/spring-credhub-starter/src/main/java/org/springframework/credhub/diagnostics/ClientNotConfiguredFailureAnalyzer.java
new file mode 100644
index 0000000..27b2631
--- /dev/null
+++ b/spring-credhub-starter/src/main/java/org/springframework/credhub/diagnostics/ClientNotConfiguredFailureAnalyzer.java
@@ -0,0 +1,70 @@
+/*
+ * Copyright 2016-2020 the original author or authors.
+ *
+ * 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
+ *
+ *     https://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.springframework.credhub.diagnostics;
+
+import org.springframework.beans.BeansException;
+import org.springframework.beans.factory.BeanFactory;
+import org.springframework.beans.factory.BeanFactoryAware;
+import org.springframework.beans.factory.NoSuchBeanDefinitionException;
+import org.springframework.boot.diagnostics.AbstractFailureAnalyzer;
+import org.springframework.boot.diagnostics.FailureAnalysis;
+import org.springframework.boot.diagnostics.FailureAnalyzer;
+
+/**
+ * A {@link FailureAnalyzer} that detects the condition when Spring CredHub has been configured
+ * with an OAuth2 client but beans required for this configuration are missing.
+ *
+ * @author Scott Frederick
+ */
+class ClientNotConfiguredFailureAnalyzer extends AbstractFailureAnalyzer<NoSuchBeanDefinitionException>
+		implements BeanFactoryAware {
+
+	private BeanFactory beanFactory;
+
+	@Override
+	protected FailureAnalysis analyze(Throwable rootFailure, NoSuchBeanDefinitionException cause) {
+		if (hasCredHubProperties() && isMissingSpringSecurityOAuth2Bean(cause.getBeanType())) {
+			return new FailureAnalysis(getDescription(), getAction(), cause);
+		}
+		return null;
+	}
+
+	private boolean hasCredHubProperties() {
+		return this.beanFactory.containsBean("credHubProperties");
+	}
+
+	private boolean isMissingSpringSecurityOAuth2Bean(Class<?> notFoundBean) {
+		return notFoundBean != null && (notFoundBean.getName().contains("ClientRegistrationRepository") ||
+				notFoundBean.getName().contains("OAuth2AuthorizedClientRepository"));
+	}
+
+	private String getDescription() {
+		return "A CredHub OAuth2 client registration is configured " +
+				"but Spring Security is not available or the Spring Security OAuth2 " +
+				"client registration not configured correctly.";
+	}
+
+	private String getAction() {
+		return "Add Spring Security to the application classpath and configure properties for the " +
+				"OAuth2 client registration under 'spring.security.oauth2.client.registration'.";
+	}
+
+	@Override
+	public void setBeanFactory(BeanFactory beanFactory) throws BeansException {
+		this.beanFactory = beanFactory;
+	}
+}
diff --git a/spring-credhub-starter/src/main/resources/META-INF/spring.factories b/spring-credhub-starter/src/main/resources/META-INF/spring.factories
index c47d2d7..041302d 100644
--- a/spring-credhub-starter/src/main/resources/META-INF/spring.factories
+++ b/spring-credhub-starter/src/main/resources/META-INF/spring.factories
@@ -2,3 +2,6 @@ org.springframework.boot.autoconfigure.EnableAutoConfiguration=\
 org.springframework.credhub.autoconfig.CredHubAutoConfiguration,\
 org.springframework.credhub.autoconfig.CredHubOAuth2AutoConfiguration,\
 org.springframework.credhub.autoconfig.CredHubTemplateAutoConfiguration
+
+org.springframework.boot.diagnostics.FailureAnalyzer=\
+org.springframework.credhub.diagnostics.ClientNotConfiguredFailureAnalyzer