keyvalue (Source Mapper)
Key-Value Map to Event input mapper extension allows transports that
accept events as key value maps to convert those events to Stream App
events. You can either receive pre-defined keys where conversion takes
place without extra configurations, or use custom keys to map from the
message.
Syntax
CREATE SOURCE <NAME> WITH (map.type="keyvalue", map.fail.on.missing.attribute="<BOOL>")
Query Parameters
| Name | Description | Default Value | Possible Data Types | Optional | Dynamic |
|---|---|---|---|---|---|
| fail.on.missing.attribute | If this parameter is set to true, if an event arrives without a matching key for a specific attribute in the connected stream, it is dropped and not processed by the Stream Processor. If this parameter is set to false the Stream Processor adds the required key to such events with a null value, and the event is converted to a Stream App event so that you could handle them as required before they are further processed. | true | BOOL | Yes | No |
Example 1
CREATE SOURCE FooStream WITH (type='inMemory', topic='stock', map.type='keyvalue') (symbol string, price float, volume long);
This query performs a default key value input mapping. The expected
input is a map similar to the following: symbol: gdn price: 55.6f
volume: 100
Example 2
CREATE SOURCE FooStream WITH (type='inMemory', topic='stock', map.type='keyvalue', map.fail.on.missing.attribute='true', map.attributes="symbol = 's', price = 'p', volume = 'v'") (symbol string, price float, volume long);
This query performs a custom key value input mapping. The matching keys
for the symbol, price and volume attributes are be s, p, and
v respectively. The expected input is a map similar to the following:
s: gdn p: 55.6 v: 100