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@@ -102,6 +102,7 @@ Verify this response as well but in a hidden block.
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For more details on specifying scripts see <<modules-scripting, script documentation>>.
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+[[scripted-metric-aggregation-return-types]]
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==== Allowed return types
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Whilst any valid script object can be used within a single script, the scripts must return or store in the `state` object only the following types:
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@@ -111,6 +112,7 @@ Whilst any valid script object can be used within a single script, the scripts m
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* Map (containing only keys and values of the types listed here)
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* Array (containing elements of only the types listed here)
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+[[scripted-metric-aggregation-scope]]
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==== Scope of scripts
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The scripted metric aggregation uses scripts at 4 stages of its execution:
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@@ -139,7 +141,8 @@ reduce_script:: Executed once on the coordinating node after all shards have
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In the above example, the `reduce_script` iterates through the `profit` returned by each shard summing the values before returning the
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final combined profit which will be returned in the response of the aggregation.
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-==== Worked Example
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+[[scripted-metric-aggregation-example]]
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+==== Worked example
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Imagine a situation where you index the following documents into an index with 2 shards:
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@@ -255,7 +258,8 @@ produce the response:
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--------------------------------------------------
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// NOTCONSOLE
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-==== Other Parameters
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+[[scripted-metric-aggregation-parameters]]
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+==== Other parameters
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[horizontal]
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params:: Optional. An object whose contents will be passed as variables to the `init_script`, `map_script` and `combine_script`. This can be
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@@ -268,7 +272,8 @@ params:: Optional. An object whose contents will be passed as variable
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--------------------------------------------------
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// NOTCONSOLE
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-==== Empty Buckets
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+[[scripted-metric-aggregation-empty-buckets]]
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+==== Empty buckets
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If a parent bucket of the scripted metric aggregation does not collect any documents an empty aggregation response will be returned from the
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shard with a `null` value. In this case the `reduce_script`'s `states` variable will contain `null` as a response from that shard.
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Lisa Cawley