Application Configuration Template Expressions
Template expressions are used to configure some Fusion pipeline stage and messaging services. When the value of a configuration parameter is a template expression, that expression is dynamically evaluated at runtime, by the StringTemplate library.
Fusion template expressions are delimited by angle bracket characters '<' and '>'. The expression consists of the name of a variable in the scope of that component. Since these variables are Java objects, if object "foo" of type Foo has a field named "bar", the expression "<foo.bar>" will evaluate to the string representation of the contents of field "bar".
Index Pipeline Stage Templates
Index stages have available variables
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"ctx" - PipelineContext (com.lucidworks.apollo.pipeline.PipelineContext)
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"doc" - PipelineDocument (com.lucidworks.apollo.common.pipeline.PipelineDocument)
For example, given a PipelineDocument which has a field named "title" with value "Star Wars", the template expression "<doc.title>" evaluates to "Star Wars".
Query Pipeline Stage Templates
Query stages have available variables:
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"ctx" - PipelineContext (com.lucidworks.apollo.pipeline.PipelineContext)
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"reqResp" - QueryRequestAndResponse (com.lucidworks.apollo.pipeline.query.QueryRequestAndResponse)
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"request" - Query Request (com.lucidworks.apollo.pipeline.query.Request)
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"response" - Query Response (com.lucidworks.apollo.pipeline.query.Response)
Messaging Services Templates
Messages have a set of variables which correspond to the parts of a system message:
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id
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to
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from
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subject
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body
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type
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schedule
A system message is the result of evaluating the following expression:
<id><to><from><subject><body><type><schedule>