Move GCP proxy code to the old [] proxy's location

1. Moved code for the GCP proxy to where the [] proxy code used to live.
3. Corrected reference to the GCP proxy location.
4. Misc changes to make ErrorProne and various tools happy.

+diekmann to LGTM terraform whitelist change.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=213630560

java/google/registry/proxy/ProxyConfig.java

@@ -0,0 +1,136 @@
+// Copyright 2017 The Nomulus Authors. All Rights Reserved.
+//
+// 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
+//
+//     http://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 google.registry.proxy;
+
+import static google.registry.config.YamlUtils.getConfigSettings;
+import static google.registry.util.ResourceUtils.readResourceUtf8;
+
+import com.google.common.base.Ascii;
+import java.util.List;
+
+/** The POJO that YAML config files are deserialized into. */
+public class ProxyConfig {
+
+  enum Environment {
+    PRODUCTION,
+    PRODUCTION_CANARY,
+    SANDBOX,
+    SANDBOX_CANARY,
+    ALPHA,
+    LOCAL,
+  }
+
+  private static final String DEFAULT_CONFIG = "config/default-config.yaml";
+  private static final String CUSTOM_CONFIG_FORMATTER = "config/proxy-config-%s.yaml";
+
+  public String projectId;
+  public List<String> gcpScopes;
+  public int accessTokenRefreshBeforeExpirationSeconds;
+  public int serverCertificateCacheSeconds;
+  public Gcs gcs;
+  public Kms kms;
+  public Epp epp;
+  public Whois whois;
+  public HealthCheck healthCheck;
+  public WebWhois webWhois;
+  public HttpsRelay httpsRelay;
+  public Metrics metrics;
+
+  /** Configuration options that apply to GCS. */
+  public static class Gcs {
+    public String bucket;
+    public String sslPemFilename;
+  }
+
+  /** Configuration options that apply to Cloud KMS. */
+  public static class Kms {
+    public String location;
+    public String keyRing;
+    public String cryptoKey;
+  }
+
+  /** Configuration options that apply to EPP protocol. */
+  public static class Epp {
+    public int port;
+    public String relayHost;
+    public String relayPath;
+    public int maxMessageLengthBytes;
+    public int headerLengthBytes;
+    public int readTimeoutSeconds;
+    public Quota quota;
+  }
+
+  /** Configuration options that apply to WHOIS protocol. */
+  public static class Whois {
+    public int port;
+    public String relayHost;
+    public String relayPath;
+    public int maxMessageLengthBytes;
+    public int readTimeoutSeconds;
+    public Quota quota;
+  }
+
+  /** Configuration options that apply to GCP load balancer health check protocol. */
+  public static class HealthCheck {
+    public int port;
+    public String checkRequest;
+    public String checkResponse;
+  }
+
+  /** Configuration options that apply to web WHOIS redirects. */
+  public static class WebWhois {
+    public int httpPort;
+    public int httpsPort;
+    public String redirectHost;
+  }
+
+  /** Configuration options that apply to HTTPS relay protocol. */
+  public static class HttpsRelay {
+    public int port;
+    public int maxMessageLengthBytes;
+  }
+
+  /** Configuration options that apply to Stackdriver monitoring metrics. */
+  public static class Metrics {
+    public int stackdriverMaxQps;
+    public int stackdriverMaxPointsPerRequest;
+    public int writeIntervalSeconds;
+  }
+
+  /** Configuration options that apply to quota management. */
+  public static class Quota {
+
+    /** Quota configuration for a specific set of users. */
+    public static class QuotaGroup {
+      public List<String> userId;
+      public int tokenAmount;
+      public int refillSeconds;
+    }
+
+    public int refreshSeconds;
+    public QuotaGroup defaultQuota;
+    public List<QuotaGroup> customQuota;
+  }
+
+  static ProxyConfig getProxyConfig(Environment env) {
+    String defaultYaml = readResourceUtf8(ProxyConfig.class, DEFAULT_CONFIG);
+    String customYaml =
+        readResourceUtf8(
+            ProxyConfig.class,
+            String.format(
+                CUSTOM_CONFIG_FORMATTER, Ascii.toLowerCase(env.name()).replace("_", "-")));
+    return getConfigSettings(defaultYaml, customYaml, ProxyConfig.class);
+  }
+}