[SENTRY-1579] Sentry should avoid using Proxy

• Type: Improvement
• Status: Open
• Priority: Minor
• Resolution: Unresolved
• Affects Version/s: 1.8.0, 2.0.0
• Component/s: Sentry
• Assignee: Unassigned
• Reporter: Alex Kolbasov
• Created: 29/Dec/16 22:25
• Updated: 24/Jul/17 14:44

Description

Sentry code uses Java java.lang.Reflect.Proxy class in several places:

SentryHDFSServiceClientFactory

uses this to modify behavior in HA case.

SentryServiceClientFactory

uses it to modify behavior in connection pool or Ha case:

  public static SentryPolicyServiceClient create(Configuration conf) throws Exception {
    boolean haEnabled = conf.getBoolean(ClientConfig.SERVER_HA_ENABLED, false);
    boolean pooled = conf.getBoolean(ClientConfig.SENTRY_POOL_ENABLED, false);
    if (pooled) {
      return (SentryPolicyServiceClient) Proxy
          .newProxyInstance(SentryPolicyServiceClientDefaultImpl.class.getClassLoader(),
              SentryPolicyServiceClientDefaultImpl.class.getInterfaces(),
              new PoolClientInvocationHandler(conf));
    } else if (haEnabled) {
      return (SentryPolicyServiceClient) Proxy
          .newProxyInstance(SentryPolicyServiceClientDefaultImpl.class.getClassLoader(),
              SentryPolicyServiceClientDefaultImpl.class.getInterfaces(),
              new HAClientInvocationHandler(conf));
    } else {
      return new SentryPolicyServiceClientDefaultImpl(conf);
    }
  }

SentryServiceClientPoolFactory

uses it to modify behavior in HA case.

This seems to be an abuse of the Proxy interface and some simpler solution should be possible. We should investigate.

Note that in sentry-ha-redesign branch there is only one use in

SentryPolicyServiceClient

that is used to adjust behavior for pooled vs retry behaviors:

  public static SentryPolicyServiceClient create(Configuration conf) throws Exception {
    boolean pooled = conf.getBoolean(
        ClientConfig.SENTRY_POOL_ENABLED, ClientConfig.SENTRY_POOL_ENABLED_DEFAULT);
    if (pooled) {
      return (SentryPolicyServiceClient) Proxy
          .newProxyInstance(SentryPolicyServiceClientDefaultImpl.class.getClassLoader(),
              SentryPolicyServiceClientDefaultImpl.class.getInterfaces(),
              new PoolClientInvocationHandler(conf));
    } else {
      return (SentryPolicyServiceClient) Proxy
          .newProxyInstance(SentryPolicyServiceClientDefaultImpl.class.getClassLoader(),
              SentryPolicyServiceClientDefaultImpl.class.getInterfaces(),
              new RetryClientInvocationHandler(conf));
    }
  }

Again, a more straightforward solution should be possible.

Issue Links

• is related to: SENTRY-1580 Provide pooled client connection model with HA
• relates to: SENTRY-872 Uber jira for HMS HA + Sentry HA redesign