feat: add json macro

README.md

@@ -49,6 +49,7 @@ This dbt package contains macros for SQL functions to run the dbt project on mul
 - [String functions](#String-functions)
   - [charindex](#charindex-source)
   - [concat](#concat-source)
+  - [json](#json-source)
 - [Aggregate functions](#Aggregate-functions)
   - [stddev](#stddev-source)
   - [string_agg](#string_agg-source)
@@ -275,6 +276,12 @@ Usage:
 To pass a string as argument, make sure to use double quotes:
 `{{ pm_utils.concat('"Field_A"', "' - '", '"Field_B"') }}`
 
+#### json ([source](macros/string_functions/json.sql))
+This macro returns the value defined in the path of a JSON string. The first argument indicates the field that stores the JSON string and the second argument is the path for which the value should be returned.
+
+Usage:
+`{{ pm_utils.json('[field]', '[path]') }}`
+
 ### Aggregate functions
 
 #### stddev ([source](macros/aggregate_functions/stddev.sql))

integration_tests/models/schema.yml

@@ -171,3 +171,12 @@ models:
     - equal_value:
         actual: '"Only_weekend"'
         expected: '"Only_weekend_expected"'
+
+  - name: test_json
+    tests:
+    - equal_value:
+        actual: '"One_level_field"'
+        expected: '"One_level_field_expected"'
+    - equal_value:
+        actual: '"Two_level_field"'
+        expected: '"Two_level_field_expected"'

integration_tests/models/test_json.sql

@@ -0,0 +1,16 @@
+with Input_data as (
+    select
+        '{"Field_A":"ABC"}' as "Column_A",
+        '{"Field_A": {"Field_B": "DEF"}}' as "Column_B",
+        null as "Column_C"
+)
+
+select
+    {# Get value from a one level path. #}
+    {{ pm_utils.json('"Column_A"', 'Field_A') }} as "One_level_field",
+    'ABC' as "One_level_field_expected",
+
+    {# Get value from a two level path. #}
+    {{ pm_utils.json('"Column_B"', 'Field_A.Field_B') }} as "Two_level_field",
+    'DEF' as "Two_level_field_expected"
+from Input_data

macros/string_functions/json.sql

@@ -0,0 +1,9 @@
+{% macro json(field, path) %}
+
+{% if target.type == 'snowflake' %}
+    JSON_EXTRACT_PATH_TEXT({{ field }}, '{{ path }}')
+{% elif target.type == 'sqlserver' %}
+    json_value({{ field }}, '{{ path }}')
+{% endif %}
+
+{% endmacro %}