c = interpolator.interpolate(value, recursionInterceptor);
                    } catch (InterpolationException e) {
                        problems.add(new ModelProblemCollectorRequest(Severity.ERROR, Version.BASE)
                                .setMessage(e.getMessage())
                                .setException(e));
                    }
                    cache.put(value, c);
                }

	}

	for id := range remove {
		b.deleteCache(id)
	}
}

// updateCacheEntry will update a cache.
// Returns the updated status.
func (b *bucketMetacache) updateCacheEntry(update metacache) (metacache, error) {
	b.mu.Lock()
	defer b.mu.Unlock()
	existing, ok := b.caches[update.id]
	if !ok {
		return update, errFileNotFound
	}
	existing.update(update)
	b.caches[update.id] = existing
	b.updated = true

	}

	if relation.Polymorphic.PolymorphicType == nil {
		schema.err = fmt.Errorf("invalid polymorphic type %v for %v on field %s, missing field %s",
			relation.FieldSchema, schema, field.Name, polymorphic+"Type")
	}

	if relation.Polymorphic.PolymorphicID == nil {
		schema.err = fmt.Errorf("invalid polymorphic type %v for %v on field %s, missing field %s",

		if errCode != testCase.errCode {
			t.Errorf("Test %d: Expected error code:%d, got %d", i+1, testCase.errCode, errCode)
		}
		if prefix != testCase.prefix {
			t.Errorf("Test %d: Expected %s, got %s", i+1, testCase.prefix, prefix)
		}
		if token != testCase.token {
			t.Errorf("Test %d: Expected %s, got %s", i+1, testCase.token, token)
		}
		if startAfter != testCase.startAfter {

  /** True if there was an exception on the connection to the peer. */
  internal var hasFailure: Boolean = false
    private set

  internal val connection: RealConnection
    get() = codec.carrier as? RealConnection ?: error("no connection for CONNECT tunnels")

  internal val isCoalescedConnection: Boolean
    get() = finder.routePlanner.address.url.host != codec.carrier.route.address.url.host

  @Throws(IOException::class)

{!> ../../docs_src/security/tutorial007.py!}
```

////

这类似于：

```Python
if not (credentials.username == "stanleyjobson") or not (credentials.password == "swordfish"):
    # Return some error
    ...
```

但使用 `secrets.compare_digest()`，可以防御**时差攻击**，更加安全。

### 时差攻击

什么是**时差攻击**？

假设攻击者试图猜出用户名与密码。

他们发送用户名为 `johndoe`，密码为 `love123`  的请求。

然后，Python 代码执行如下操作：

# This should only be necessary when running on A GCP VM, on a default
# network, which has the MTU of 1460,
# due to 40 bytes being reserved for GCP's internal usage.
# Note, an invalid sub-interface name will lead to an obscure error, e.g.:
# "The filename, directory name, or volume label syntax is incorrect."
# In such cases, check that the name of the sub-interface is valid:
# `netsh interface show interface`

        return false
      }
    }
    if (e is SSLPeerUnverifiedException) {
      // e.g. a certificate pinning error.
      return false
    }
    // An example of one we might want to retry with a different route is a problem connecting to a
    // proxy and would manifest as a standard IOException. Unless it is one we know we should not
    // retry, we return true and try a new route.

        try {
            updateRepositoryMetadata(localRepository, remoteRepository);
        } catch (IOException | XMLStreamException e) {
            throw new RepositoryMetadataStoreException("Error updating group repository metadata", e);
        }
    }

    protected void updateRepositoryMetadata(ArtifactRepository localRepository, ArtifactRepository remoteRepository)

	hstats.totalS3Requests.Inc(api)
	code := w.StatusCode

	switch {
	case code == 0:
	case code == 499:
		// 499 is a good error, shall be counted as canceled.
		hstats.totalS3Canceled.Inc(api)
	case code >= http.StatusBadRequest:
		if code >= http.StatusInternalServerError {
			hstats.totalS35xxErrors.Inc(api)
		} else {