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Formula - Extract
Use the Nodinite Extract function group to retrieve values from structured and unstructured content in a Log Event. This page gives you a practical overview of each Extract function and links to detailed function pages.
- ✅ Extract from JSON, XML, CSV, and plain text content
- ✅ Read values from Body, Context, or nested Formula output
- ✅ Combine Extract functions with Convert, Logical, Alter, and Math functions
- ✅ Build robust Search Field Expressions for Search Fields and [Log Views][]
What does the Extract function group do?
Extract functions read content and return one or more values that can be used directly in a Search Field expression or passed to other Formula functions.
The content input can be:
How it works
graph LR
A["Log Event"] --> B{"Content"}
B -->|Body| C["Extract Function"]
B -->|Context| C
B -->|Nested Formula Output| C
C --> D["Extracted Value(s)"]
D --> E["Search Field Result"]
Flow: An Extract function reads content from Body, Context, or nested output and returns value(s) for the Search Field result.
Extract function catalog
| Function | Purpose | Typical Input |
|---|---|---|
| jsonPath | Extract values from JSON using JSONPath expressions | JSON body or context value |
| JsonPathKey | Extract JSON property keys | JSON body or context value |
| xPath | Extract values from XML using XPath 1.0 | XML body or context value |
| xPath2 | Extract values from XML using XPath 2.0 | XML body or context value |
| regex | Extract values from text using Regular Expressions | Text body or context value |
| regexGroup | Extract capture groups from RegEx matches | Text body or context value |
| csv | Extract values from CSV using row, delimiter, and column settings | CSV body or context value |
| sqllookup | Enrich values with SQL lookups using a query | Content value used as query parameter |
Common syntax patterns
Use these patterns when authoring Search Field Expressions:
jsonpath('$.order.id', body)
xpath('/Orders/Order/Id', body)
regex('\\d+', context('MessageText'))
csv(1, ',', 2, '#', body)
regexGroup('(OrderId):(\\d+)', '2', body)
sqllookup('connectionString', 'select Name from dbo.Customer where Id = @value', jsonpath('$.customerId', body))
Important considerations
xPath()is usually the best first choice for XML performance.xPath2()supports more advanced XML queries but can use more memory.- RegEx and JSON extraction functions parse full content; test large payloads with realistic data.
sqllookup()introduces external dependencies and database latency; validate connectivity and response time.
How to use
To use an Extract function:
- Open Add or manage Search Field.
- Choose Formula as the expression type.
- Add one or more Extract functions using the syntax patterns above.
- Test with representative payload and context values.
- Save and validate the output in your Log View.