Source for specific tables (#51)

* Addig another parameter to pass a list of tables to generate_source

* Addig another parameter to pass a list of tables to generate_source

* Updated README

* Updated changelog

* Apply suggestions from code review

* Update integration_tests/tests/test_generate_source_some_tables.sql

Co-authored-by: Doug Beatty <44704949+dbeatty10@users.noreply.github.com>

CHANGELOG.md

@@ -3,6 +3,7 @@
 - Add support for importing descriptions from columns with the same names in upstream models. It is available by setting the parameter `upstream_descriptions` to `True` in `generate_model_yaml` ([#61](https://github.com/dbt-labs/dbt-codegen/pull/61))
 - Add support for including description placeholders for the source and table, which changes the behavior of `generate_source` when `include_descriptions` is set to `True`. Previous logic only created description placeholders for the columns. 
 - Add optional `name` arg to `generate_source`
+- Add optional `table_names` arg to `generate_source` (#50 @rahulj51)
 
 # dbt-codegen v0.6.0
 

README.md

@@ -21,6 +21,7 @@ which you can then paste into a schema file.
 * `schema_name` (required): The schema name that contains your source data
 * `database_name` (optional, default=target.database): The database that your
 source data is in.
+* `table_names` (optional, default=none): A list of tables that you want to generate the source definitions for.
 * `generate_columns` (optional, default=False): Whether you want to add the
 column names to your source definition.
 * `include_descriptions` (optional, default=False): Whether you want to add 
@@ -47,7 +48,7 @@ or
 
 ```
 # for multiple arguments, use the dict syntax
-$ dbt run-operation generate_source --args '{"schema_name": "jaffle_shop", "database_name": "raw"}'
+$ dbt run-operation generate_source --args '{"schema_name": "jaffle_shop", "database_name": "raw", "table_names":["table_1", "table_2"]}'
 ```
 
 2. The YAML for the source will be logged to the command line

integration_tests/tests/test_generate_source_some_tables.sql

@@ -0,0 +1,30 @@
+{% set raw_schema = generate_schema_name('raw_data') %}
+
+-- test all args
+{% set actual_source_yaml = codegen.generate_source(
+    schema_name=raw_schema,
+    database_name=target.database,
+    table_names=['data__a_relation'],
+    generate_columns=True,
+    include_descriptions=True
+) %}
+
+
+{% set expected_source_yaml %}
+version: 2
+
+sources:
+  - name: {{ raw_schema | trim }}
+    description: ""
+    tables:
+      - name: data__a_relation
+        description: ""
+        columns:
+          - name: col_a
+            description: ""
+          - name: col_b
+            description: ""
+
+{% endset %}
+
+{{ assert_equal (actual_source_yaml | trim, expected_source_yaml | trim) }}

macros/generate_source.sql

@@ -15,7 +15,7 @@
 
 
 ---
-{% macro generate_source(schema_name, database_name=target.database, generate_columns=False, include_descriptions=False, table_pattern='%', exclude='', name=schema_name) %}
+{% macro generate_source(schema_name, database_name=target.database, generate_columns=False, include_descriptions=False, table_pattern='%', exclude='', name=schema_name, table_names=None) %}
 
 {% set sources_yaml=[] %}
 {% do sources_yaml.append('version: 2') %}
@@ -37,7 +37,11 @@
 
 {% do sources_yaml.append('    tables:') %}
 
+{% if table_names is none %}
 {% set tables=codegen.get_tables_in_schema(schema_name, database_name, table_pattern, exclude) %}
+{% else %}
+{% set tables = table_names %}
+{% endif %}
 
 {% for table in tables %}
     {% do sources_yaml.append('      - name: ' ~ table | lower ) %}