Replacement values

Use the TRY dynamic expression to enter a replacement value for a step property if a specific dynamic value can't be found. For example, if you want to read a buffered value that doesn't exist and don't want an exception, use the replacement value.

Use the value {TRY[<dynamic expression>][<replacement>]} with the Insert step property to define a replacement value.

Example

In this example, we read data from a resource named movies using the FROM expression.

The insert step tries to insert a value from the movies resource. Specifically, it reads the value of the title column from the row whose id matches the buffered id. If it doesn't find a value, the replacement value movie not found is used.

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schema: SimV1
name: Test01

resources:
- name: movies    
  file: movies.csv

services:

- name: movies    
  steps:      
  - trigger:          
    - uri: /movies/*        
    buffer:          
    - type: Path            
      value: '/movies/{xb[id]}'      
  - insert:          
      - value: '{TRY[{FROM[movies][title][id = "{B[id]}"]}][movie not found]'