run_query: add metadata comment to all queries run with elementary.run.query (#828)

* run_query: add metadata comment to all queries run with elementary.run_query

* use dict access

* safety

* newline

* use leading comments unless the adapter is Snowflake

Author: haritamar

macros/utils/run_queries/run_query.sql

@@ -1,5 +1,5 @@
 {% macro run_query(query, lowercase_column_names=True) %}
-    {% set query_result = dbt.run_query(query) %}
+    {% set query_result = dbt.run_query(elementary.format_query_with_metadata(query)) %}
     {% if lowercase_column_names %}
         {% set lowercased_column_names = {} %}
         {% for column_name in query_result.column_names %}
@@ -10,3 +10,42 @@
 
     {% do return(query_result) %}
 {% endmacro %}
+
+{% macro format_query_with_metadata(query) %}
+    {% do return(adapter.dispatch('format_query_with_metadata', 'elementary')(query)) %}
+{% endmacro %}
+
+{% macro default__format_query_with_metadata(query) %}
+    /* --ELEMENTARY-METADATA-- {{ elementary.get_elementary_query_metadata() | tojson }} --END-ELEMENTARY-METADATA-- */
+    {{ query }}
+{% endmacro %}
+
+{% macro snowflake__format_query_with_metadata(query) %}
+    {# Snowflake removes leading comments #}
+    {{ query }}
+    /* --ELEMENTARY-METADATA-- {{ elementary.get_elementary_query_metadata() | tojson }} --END-ELEMENTARY-METADATA-- */
+{% endmacro %}
+
+{% macro get_elementary_query_metadata() %}
+    {% set metadata = {
+        "invocation_id": invocation_id,
+        "command": flags.WHICH
+    } %}
+
+    {% if model %}
+        {% do metadata.update({
+            'package_name': model['package_name'],
+            'resource_name': model['name'],
+            'resource_type': model['resource_type']
+        }) %}
+        {% if model.resource_type == 'test' %}
+            {% set test_metadata = model.get('test_metadata', {}) %}
+            {% do metadata.update({
+                'test_short_name': test_metadata.get("name"),
+                'test_namespace': test_metadata.get("namespace")
+            }) %}
+        {% endif %}
+    {% endif %}
+
+    {% do return(metadata) %}
+{% endmacro %}