Edge cache integration

BaragonCore/src/main/java/com/hubspot/baragon/models/BaragonService.java

@@ -41,14 +41,17 @@ public class BaragonService {
 
   private final Set<String> domains;
 
+  private final Optional<String> edgeCacheDNS;
+
   public BaragonService(@JsonProperty("serviceId") String serviceId,
                         @JsonProperty("owners") Collection<String> owners,
                         @JsonProperty("serviceBasePath") String serviceBasePath,
                         @JsonProperty("additionalPaths") List<String> additionalPaths,
                         @JsonProperty("loadBalancerGroups") Set<String> loadBalancerGroups,
                         @JsonProperty("options") Map<String, Object> options,
                         @JsonProperty("templateName") Optional<String> templateName,
-                        @JsonProperty("domains") Set<String> domains) {
+                        @JsonProperty("domains") Set<String> domains,
+                        @JsonProperty("edgeCacheDNS") Optional<String> edgeCacheDNS) {
     this.serviceId = serviceId;
     this.owners = owners;
     this.serviceBasePath = serviceBasePath;
@@ -57,14 +60,19 @@ public BaragonService(@JsonProperty("serviceId") String serviceId,
     this.options = options;
     this.templateName = templateName;
     this.domains = MoreObjects.firstNonNull(domains, Collections.<String>emptySet());
+    this.edgeCacheDNS = edgeCacheDNS;
+  }
+
+  public BaragonService(String serviceId, Collection<String> owners, String serviceBasePath, List<String> additionalPaths, Set<String> loadBalancerGroups, Map<String, Object> options, Optional<String> templateName, Set<String> domains) {
+    this(serviceId, owners, serviceBasePath, additionalPaths, loadBalancerGroups, options, templateName, domains, Optional.absent());
   }
 
   public BaragonService(String serviceId, Collection<String> owners, String serviceBasePath, List<String> additionalPaths, Set<String> loadBalancerGroups, Map<String, Object> options, Optional<String> templateName) {
-    this(serviceId, owners, serviceBasePath, additionalPaths, loadBalancerGroups, options, templateName, Collections.<String>emptySet());
+    this(serviceId, owners, serviceBasePath, additionalPaths, loadBalancerGroups, options, templateName, Collections.<String>emptySet(), Optional.absent());
   }
 
   public BaragonService(String serviceId, Collection<String> owners, String serviceBasePath, Set<String> loadBalancerGroups, Map<String, Object> options) {
-    this(serviceId, owners, serviceBasePath, Collections.<String>emptyList(), loadBalancerGroups, options, Optional.<String>absent(), Collections.<String>emptySet());
+    this(serviceId, owners, serviceBasePath, Collections.<String>emptyList(), loadBalancerGroups, options, Optional.<String>absent(), Collections.<String>emptySet(), Optional.absent());
   }
 
   public String getServiceId() {
@@ -87,6 +95,9 @@ public Set<String> getLoadBalancerGroups() {
     return loadBalancerGroups;
   }
 
+  /**
+   * Data from this field is primarily used to populate data in rendered nginx config templates.
+   */
   public Map<String, Object> getOptions() {
     return options;
   }
@@ -99,6 +110,10 @@ public Set<String> getDomains() {
     return domains;
   }
 
+  public Optional<String> getEdgeCacheDNS() {
+    return edgeCacheDNS;
+  }
+
   @JsonIgnore
   public List<String> getAllPaths() {
     List<String> allPaths = new ArrayList<>();
@@ -131,6 +146,7 @@ public String toString() {
         ", options=" + options +
         ", templateName=" + templateName +
         ", domains=" + domains +
+        ", edgeCacheDNS=" + edgeCacheDNS +
         ']';
   }
 
@@ -169,6 +185,9 @@ public boolean equals(Object o) {
     if (domains != null ? !domains.equals(service.domains) : service.domains != null) {
       return false;
     }
+    if (edgeCacheDNS != null ? !edgeCacheDNS.equals(service.edgeCacheDNS) : service.edgeCacheDNS != null) {
+      return false;
+    }
 
     return true;
   }
@@ -183,6 +202,7 @@ public int hashCode() {
     result = 31 * result + (options != null ? options.hashCode() : 0);
     result = 31 * result + (templateName != null ? templateName.hashCode() : 0);
     result = 31 * result + (domains != null ? domains.hashCode() : 0);
+    result = 31 * result + (edgeCacheDNS != null ? edgeCacheDNS.hashCode() : 0);
     return result;
   }
 }

BaragonService/pom.xml

@@ -124,6 +124,10 @@
       <groupId>com.fasterxml.jackson.datatype</groupId>
       <artifactId>jackson-datatype-guava</artifactId>
     </dependency>
+    <dependency>
+      <groupId>com.hubspot</groupId>
+      <artifactId>HorizonCore</artifactId>
+    </dependency>
     <dependency>
       <groupId>io.dropwizard</groupId>
       <artifactId>dropwizard-core</artifactId>

BaragonService/src/main/java/com/hubspot/baragon/service/BaragonServiceModule.java

@@ -29,8 +29,12 @@
 import com.hubspot.baragon.data.BaragonConnectionStateListener;
 import com.hubspot.baragon.data.BaragonWorkerDatastore;
 import com.hubspot.baragon.service.config.BaragonConfiguration;
+import com.hubspot.baragon.service.config.EdgeCacheConfiguration;
 import com.hubspot.baragon.service.config.ElbConfiguration;
 import com.hubspot.baragon.service.config.SentryConfiguration;
+import com.hubspot.baragon.service.edgecache.EdgeCache;
+import com.hubspot.baragon.service.edgecache.cloudflare.CloudflareEdgeCache;
+import com.hubspot.baragon.service.edgecache.cloudflare.client.CloudflareClient;
 import com.hubspot.baragon.service.elb.ApplicationLoadBalancer;
 import com.hubspot.baragon.service.elb.ClassicLoadBalancer;
 import com.hubspot.baragon.service.exceptions.BaragonExceptionNotifier;
@@ -99,6 +103,11 @@ public void configure(Binder binder) {
     binder.bind(ServiceManager.class).in(Scopes.SINGLETON);
     binder.bind(StatusManager.class).in(Scopes.SINGLETON);
 
+    // Edge Cache
+    binder.bind(CloudflareEdgeCache.class);
+    binder.bind(CloudflareClient.class);
+    binder.bind(EdgeCache.class).to(getConfiguration().getEdgeCacheConfiguration().getEdgeCache().getEdgeCacheClass());
+
     // Workers
     binder.bind(BaragonElbSyncWorker.class).in(Scopes.SINGLETON);
     binder.bind(BaragonRequestWorker.class).in(Scopes.SINGLETON);
@@ -107,7 +116,6 @@ public void configure(Binder binder) {
     binder.bind(ClassicLoadBalancer.class);
     binder.bind(ApplicationLoadBalancer.class);
 
-
     Multibinder<AbstractLatchListener> latchBinder = Multibinder.newSetBinder(binder, AbstractLatchListener.class);
     latchBinder.addBinding().to(RequestWorkerListener.class).in(Scopes.SINGLETON);
     latchBinder.addBinding().to(ElbSyncWorkerListener.class).in(Scopes.SINGLETON);
@@ -158,6 +166,11 @@ public Optional<ElbConfiguration> providesElbConfiguration(BaragonConfiguration
     return configuration.getElbConfiguration();
   }
 
+  @Provides
+  public EdgeCacheConfiguration providesEdgeCacheConfiguration(BaragonConfiguration configuration) {
+    return configuration.getEdgeCacheConfiguration();
+  }
+
   @Provides
   @Singleton
   @Named(BARAGON_SERVICE_SCHEDULED_EXECUTOR)

BaragonService/src/main/java/com/hubspot/baragon/service/config/BaragonConfiguration.java

@@ -70,6 +70,9 @@ public class BaragonConfiguration extends Configuration {
   @JsonProperty("elb")
   private Optional<ElbConfiguration> elb = Optional.absent();
 
+  @JsonProperty("edgeCache")
+  private EdgeCacheConfiguration edgeCache = new EdgeCacheConfiguration();
+
   @JsonProperty("ui")
   @Valid
   private UIConfiguration uiConfiguration = new UIConfiguration();
@@ -184,6 +187,14 @@ public void setElbConfiguration(Optional<ElbConfiguration> elb) {
     this.elb = elb;
   }
 
+  public EdgeCacheConfiguration getEdgeCacheConfiguration() {
+    return edgeCache;
+  }
+
+  public void setEdgeCacheConfiguration(EdgeCacheConfiguration edgeCache) {
+    this.edgeCache = edgeCache;
+  }
+
   public UIConfiguration getUiConfiguration() {
     return uiConfiguration;
   }

BaragonService/src/main/java/com/hubspot/baragon/service/config/EdgeCacheConfiguration.java

@@ -0,0 +1,54 @@
+package com.hubspot.baragon.service.config;
+
+import java.util.HashMap;
+import java.util.Map;
+
+import javax.validation.constraints.NotNull;
+
+import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
+import com.fasterxml.jackson.annotation.JsonProperty;
+import com.hubspot.baragon.service.edgecache.cloudflare.EdgeCacheClass;
+
+@JsonIgnoreProperties(ignoreUnknown = true)
+public class EdgeCacheConfiguration {
+
+  @JsonProperty
+  @NotNull
+  private boolean enabled = false;
+
+  @JsonProperty
+  @NotNull
+  private EdgeCacheClass edgeCache = EdgeCacheClass.CLOUDFLARE;
+
+  @JsonProperty
+  @NotNull
+  private Map<String, String> integrationSettings = new HashMap<>();
+
+  public boolean isEnabled() {
+    return enabled;
+  }
+
+  public EdgeCacheConfiguration setEnabled(boolean enabled) {
+    this.enabled = enabled;
+    return this;
+  }
+
+  public EdgeCacheClass getEdgeCache() {
+    return edgeCache;
+  }
+
+  public EdgeCacheConfiguration setEdgeCache(EdgeCacheClass edgeCache) {
+    this.edgeCache = edgeCache;
+    return this;
+  }
+
+  public Map<String, String> getIntegrationSettings() {
+    return integrationSettings;
+  }
+
+  public EdgeCacheConfiguration setIntegrationSettings(Map<String, String> integrationSettings) {
+    this.integrationSettings = integrationSettings;
+    return this;
+  }
+
+}

BaragonService/src/main/java/com/hubspot/baragon/service/edgecache/EdgeCache.java

@@ -0,0 +1,9 @@
+package com.hubspot.baragon.service.edgecache;
+
+import com.hubspot.baragon.models.BaragonRequest;
+
+public interface EdgeCache {
+
+  boolean invalidateIfNecessary(BaragonRequest request);
+
+}

BaragonService/src/main/java/com/hubspot/baragon/service/edgecache/cloudflare/CloudflareEdgeCache.java

@@ -0,0 +1,105 @@
+package com.hubspot.baragon.service.edgecache.cloudflare;
+
+import java.util.Collections;
+import java.util.Optional;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import com.google.inject.Inject;
+import com.hubspot.baragon.models.BaragonRequest;
+import com.hubspot.baragon.service.config.EdgeCacheConfiguration;
+import com.hubspot.baragon.service.edgecache.EdgeCache;
+import com.hubspot.baragon.service.edgecache.cloudflare.client.CloudflareClient;
+import com.hubspot.baragon.service.edgecache.cloudflare.client.CloudflareClientException;
+import com.hubspot.baragon.service.edgecache.cloudflare.client.models.CloudflareDnsRecord;
+import com.hubspot.baragon.service.edgecache.cloudflare.client.models.CloudflareZone;
+
+/**
+ * An implementation of a proxying edge cache backed by Cloudflare.
+ *
+ * Config example:
+ * ...
+ * edgeCache:
+ *   enabled: true
+ *   edgeCacheClass: CLOUDFLARE
+ *   integrationSettings:
+ *     apiBase: https://api.cloudflare.com/client/v4/
+ *     apiEmail: email@host.net
+ *     apiKey: some-key
+ *     cacheTagFormat: cache-tag-for-%-service
+ * ...
+ */
+public class CloudflareEdgeCache implements EdgeCache {
+  private static final Logger LOG = LoggerFactory.getLogger(CloudflareEdgeCache.class);
+
+  private final CloudflareClient cf;
+  private final EdgeCacheConfiguration edgeCacheConfiguration;
+
+  @Inject
+  public CloudflareEdgeCache(CloudflareClient cf, EdgeCacheConfiguration edgeCacheConfiguration) {
+    this.cf = cf;
+    this.edgeCacheConfiguration = edgeCacheConfiguration;
+  }
+
+  /**
+   * Invalidation will eventually occur when the TTL expires, so it's not a showstopper if this fails.
+   */
+  @Override
+  public boolean invalidateIfNecessary(BaragonRequest request) {
+    if (!request.getLoadBalancerService().getEdgeCacheDNS().isPresent()) {
+      return false;
+    }
+
+    try {
+      String edgeCacheDNS = request.getLoadBalancerService().getEdgeCacheDNS().get();
+      Optional<CloudflareZone> matchingZone = getCloudflareZone(edgeCacheDNS);
+
+      if (!matchingZone.isPresent()) {
+        LOG.warn("`edgeCacheDNS` was defined on the request, but no matching Cloudflare Zone was found!");
+        return false;
+      }
+
+      String zoneId = matchingZone.get().getId();
+      Optional<CloudflareDnsRecord> matchingDnsRecord = getCloudflareDnsRecord(edgeCacheDNS, zoneId);
+
+      if (!matchingDnsRecord.isPresent()) {
+        LOG.warn("`edgeCacheDNS` was defined on the request, but no matching Cloudflare DNS Record was found!");
+        return false;
+      }
+
+      if (!matchingDnsRecord.get().isProxied()) {
+        LOG.warn("`edgeCacheDNS` was defined on the request, but {} is not a proxied DNS record!", edgeCacheDNS);
+        return false;
+      }
+
+      String cacheTag = String.format(
+          edgeCacheConfiguration.getIntegrationSettings().get("cacheTagFormat"),
+          request.getLoadBalancerService().getServiceId()
+      );
+
+      LOG.debug("Sending cache purge request against {} for {} to Cloudflare...", matchingDnsRecord.get().getName(), cacheTag);
+
+      return cf.purgeEdgeCache(zoneId, Collections.singletonList(cacheTag));
+
+    } catch (CloudflareClientException e) {
+      LOG.error("Unable to invalidate Cloudflare cache for request {}", request, e);
+      return false;
+    }
+  }
+
+  private Optional<CloudflareDnsRecord> getCloudflareDnsRecord(String edgeCacheDNS, String zoneId) throws CloudflareClientException {
+    return Optional.ofNullable(cf.getDnsRecord(zoneId, edgeCacheDNS));
+  }
+
+  private Optional<CloudflareZone> getCloudflareZone(String edgeCacheDNS) throws CloudflareClientException {
+    String baseDomain = getBaseDomain(edgeCacheDNS);
+    return Optional.ofNullable(cf.getZone(baseDomain));
+  }
+
+  private String getBaseDomain(String dns) {
+    String[] domainTokens = dns.split("\\.");
+    return String.format("%s.%s", domainTokens[domainTokens.length - 2], domainTokens[domainTokens.length - 1]);
+  }
+
+}

BaragonService/src/main/java/com/hubspot/baragon/service/edgecache/cloudflare/EdgeCacheClass.java

@@ -0,0 +1,18 @@
+package com.hubspot.baragon.service.edgecache.cloudflare;
+
+import com.hubspot.baragon.service.edgecache.EdgeCache;
+
+public enum EdgeCacheClass {
+  CLOUDFLARE(CloudflareEdgeCache.class);
+
+  private final Class<? extends EdgeCache> edgeCacheClass;
+
+  EdgeCacheClass(Class<? extends EdgeCache> edgeCacheClass) {
+    this.edgeCacheClass = edgeCacheClass;
+  }
+
+  public Class<? extends EdgeCache> getEdgeCacheClass() {
+    return edgeCacheClass;
+  }
+
+}