ResponseContext.Key (druid-processing 0.20.1 API)

java.lang.Object
- java.lang.Enum<ResponseContext.Key>
- - org.apache.druid.query.context.ResponseContext.Key

All Implemented Interfaces:: Serializable, Comparable<ResponseContext.Key>, ResponseContext.BaseKey

Enclosing class:: ResponseContext

public static enum ResponseContext.Key
extends Enum<ResponseContext.Key>
implements ResponseContext.BaseKey

Keys associated with objects in the context.

If it's necessary to have some new keys in the context then they might be listed in a separate enum:

 public enum ExtensionResponseContextKey implements BaseKey
 {
   EXTENSION_KEY_1("extension_key_1"), EXTENSION_KEY_2("extension_key_2");

   static {
     for (BaseKey key : values()) ResponseContext.Key.registerKey(key);
   }

   private final String name;
   private final BiFunction mergeFunction;

   ExtensionResponseContextKey(String name)
   {
     this.name = name;
     this.mergeFunction = (oldValue, newValue) -> newValue;
   }

Enum Constant Summary

Enum Constants
Enum Constant and Description
`CPU_CONSUMED_NANOS` The total CPU time for threads related to Sequence processing of the query.
`ETAG` Entity tag.
`MISSING_SEGMENTS` Lists missing segments.
`NUM_SCANNED_ROWS` The number of scanned rows.
`QUERY_FAIL_DEADLINE_MILLIS` Query fail time (current time + timeout).
`QUERY_TOTAL_BYTES_GATHERED` Query total bytes gathered.
`REMAINING_RESPONSES_FROM_QUERY_SERVERS` Map of most relevant query ID to remaining number of responses from query nodes.
`TIMEOUT_AT` This variable indicates when a running query should be expired, and is effective only when 'timeout' of queryContext has a positive value.
`TRUNCATED` Indicates if a `ResponseContext` was truncated during serialization.
`UNCOVERED_INTERVALS` Lists intervals for which NO segment is present.
`UNCOVERED_INTERVALS_OVERFLOWED` Indicates if the number of uncovered intervals exceeded the limit (true/false).

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`static Collection<ResponseContext.BaseKey>`	`getAllRegisteredKeys()` Returns all keys registered via `registerKey(org.apache.druid.query.context.ResponseContext.BaseKey)`.
`BiFunction<Object,Object,Object>`	`getMergeFunction()` Merge function associated with a key: Object (Object oldValue, Object newValue)
`String`	`getName()`
`static ResponseContext.BaseKey`	`keyOf(String name)` Returns a registered key associated with the name .
`static void`	`registerKey(ResponseContext.BaseKey key)` Primary way of registering context keys.
`static ResponseContext.Key`	`valueOf(String name)` Returns the enum constant of this type with the specified name.
`static ResponseContext.Key[]`	`values()` Returns an array containing the constants of this enum type, in the order they are declared.

Methods inherited from class java.lang.Enum
clone, compareTo, equals, finalize, getDeclaringClass, hashCode, name, ordinal, toString, valueOf

Methods inherited from class java.lang.Object
getClass, notify, notifyAll, wait, wait, wait

- Enum Constant Detail
  - UNCOVERED_INTERVALS
```
public static final ResponseContext.Key UNCOVERED_INTERVALS
```
    Lists intervals for which NO segment is present.
  - UNCOVERED_INTERVALS_OVERFLOWED
```
public static final ResponseContext.Key UNCOVERED_INTERVALS_OVERFLOWED
```
    Indicates if the number of uncovered intervals exceeded the limit (true/false).
  - REMAINING_RESPONSES_FROM_QUERY_SERVERS
```
public static final ResponseContext.Key REMAINING_RESPONSES_FROM_QUERY_SERVERS
```
    Map of most relevant query ID to remaining number of responses from query nodes. The value is initialized in CachingClusteredClient when it initializes the connection to the query nodes, and is updated whenever they respond (@code DirectDruidClient). RetryQueryRunner uses this value to check if the MISSING_SEGMENTS is valid. Currently, the broker doesn't run subqueries in parallel, the remaining number of responses will be updated one by one per subquery. However, since it can be parallelized to run subqueries simultaneously, we store them in a ConcurrentHashMap.
    
    See Also:
    
    Query.getMostSpecificId()
  - MISSING_SEGMENTS
```
public static final ResponseContext.Key MISSING_SEGMENTS
```
    Lists missing segments.
  - ETAG
```
public static final ResponseContext.Key ETAG
```
    Entity tag. A part of HTTP cache validation mechanism. Is being removed from the context before sending and used as a separate HTTP header.
  - QUERY_FAIL_DEADLINE_MILLIS
```
public static final ResponseContext.Key QUERY_FAIL_DEADLINE_MILLIS
```
    Query fail time (current time + timeout). It is not updated continuously as TIMEOUT_AT.
  - QUERY_TOTAL_BYTES_GATHERED
```
public static final ResponseContext.Key QUERY_TOTAL_BYTES_GATHERED
```
    Query total bytes gathered.
  - TIMEOUT_AT
```
public static final ResponseContext.Key TIMEOUT_AT
```
    This variable indicates when a running query should be expired, and is effective only when 'timeout' of queryContext has a positive value. Continuously updated by ScanQueryEngine by reducing its value on the time of every scan iteration.
  - NUM_SCANNED_ROWS
```
public static final ResponseContext.Key NUM_SCANNED_ROWS
```
    The number of scanned rows. For backward compatibility the context key name still equals to "count".
  - CPU_CONSUMED_NANOS
```
public static final ResponseContext.Key CPU_CONSUMED_NANOS
```
    The total CPU time for threads related to Sequence processing of the query. Resulting value on a Broker is a sum of downstream values from historicals / realtime nodes. For additional information see CPUTimeMetricQueryRunner
  - TRUNCATED
```
public static final ResponseContext.Key TRUNCATED
```
    Indicates if a ResponseContext was truncated during serialization.
- Method Detail
  - values
```
public static ResponseContext.Key[] values()
```
    Returns an array containing the constants of this enum type, in the order they are declared. This method may be used to iterate over the constants as follows:
```
for (ResponseContext.Key c : ResponseContext.Key.values())
    System.out.println(c);
```
    Returns:
    
    an array containing the constants of this enum type, in the order they are declared
  - valueOf
```
public static ResponseContext.Key valueOf(String name)
```
    Returns the enum constant of this type with the specified name. The string must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)
    
    Parameters:
    
    name - the name of the enum constant to be returned.
    
    Returns:
    
    the enum constant with the specified name
    
    Throws:
    
    IllegalArgumentException - if this enum type has no constant with the specified name
    
    NullPointerException - if the argument is null
  - registerKey
```
public static void registerKey(ResponseContext.BaseKey key)
```
    Primary way of registering context keys.
    
    Throws:
    
    IllegalArgumentException - if the key has already been registered.
  - keyOf
```
public static ResponseContext.BaseKey keyOf(String name)
```
    Returns a registered key associated with the name .
    
    Throws:
    
    IllegalStateException - if a corresponding key has not been registered.
  - getAllRegisteredKeys
```
public static Collection<ResponseContext.BaseKey> getAllRegisteredKeys()
```
    Returns all keys registered via registerKey(org.apache.druid.query.context.ResponseContext.BaseKey).
  - getName
```
public String getName()
```
    Specified by:
    
    getName in interface ResponseContext.BaseKey
  - getMergeFunction
```
public BiFunction<Object,Object,Object> getMergeFunction()
```
    Description copied from interface: ResponseContext.BaseKey
    
    Merge function associated with a key: Object (Object oldValue, Object newValue)
    
    Specified by:
    
    getMergeFunction in interface ResponseContext.BaseKey

Enum ResponseContext.Key

Enum Constant Summary

Method Summary

Methods inherited from class java.lang.Enum

Methods inherited from class java.lang.Object

Enum Constant Detail

UNCOVERED_INTERVALS

UNCOVERED_INTERVALS_OVERFLOWED

REMAINING_RESPONSES_FROM_QUERY_SERVERS

MISSING_SEGMENTS

ETAG

QUERY_FAIL_DEADLINE_MILLIS

QUERY_TOTAL_BYTES_GATHERED

TIMEOUT_AT

NUM_SCANNED_ROWS

CPU_CONSUMED_NANOS

TRUNCATED

Method Detail

values

valueOf

registerKey

keyOf

getAllRegisteredKeys

getName

getMergeFunction