Add query for get all versions of one article

src/main/resources/sql/functions/article/find_articles_versions_by_id.sql

@@ -0,0 +1,11 @@
+create or replace function find_articles_versions_by_id(in _id uuid, out resource json) language plpgsql as
+$$
+declare
+    _version_id uuid = (select version_id from article where id = _id);
+begin
+    select find_articles_versions_by_version_id(_version_id)
+    into resource;
+end;
+$$;
+
+-- drop function if exists find_articles_versions_by_id(uuid, out json);

src/main/resources/sql/functions/article/find_articles_versions_by_version_id.sql

@@ -0,0 +1,17 @@
+create or replace function find_articles_versions_by_version_id(in _version_id uuid, out resource json) language plpgsql as
+$$
+begin
+    select json_agg(t order by t.version_number desc)
+    into resource
+    from (
+        select
+            a.*,
+            find_citizen_by_id(a.created_by_id) as created_by
+        from article as a
+        where a.version_id = _version_id
+        order by a.version_number desc
+    ) as t;
+end;
+$$;
+
+-- drop function if exists find_articles_versions_by_version_id(uuid, out json);

src/test/sql/article.sql

@@ -24,10 +24,20 @@ begin
     select upsert_article(created_article) into created_article;
     assert created_article->>'version_id' is not null, 'version_id should not be null';
     assert (created_article->>'version_number')::int = 1, format('version_number must be equal to 1, %s instead', created_article->>'version_number');
-    -- try tu create new version
+    -- try to create new version
     select upsert_article(created_article) into created_article;
     assert (created_article->>'version_number')::int = 2, format('version_number must be equal to 2, %s instead', created_article->>'version_number');
 
+    -- get articles versions by version_id
+    select find_articles_versions_by_version_id((created_article->>'version_id')::uuid) into selected_article;
+    assert selected_article#>>'{0,title}' = 'Love the world', format('title must be "Love the world", %s', selected_article#>>'{0,title}');
+    assert (selected_article#>>'{0,version_number}')::int = 2, format('version_id must be 2, %s instead', selected_article#>>'{0,version_number}');
+
+    -- get articles versions by id
+    select find_articles_versions_by_id((created_article->>'id')::uuid) into selected_article;
+    assert selected_article#>>'{0,title}' = 'Love the world', format('title must be "Love the world", %s', selected_article#>>'{0,title}');
+    assert (selected_article#>>'{0,version_number}')::int = 2, format('version_id must be 2, %s instead', selected_article#>>'{0,version_number}');
+
     -- get article by id and check the title
     select find_article_by_id((created_article->>'id')::uuid) into selected_article;
     assert selected_article->>'title' = 'Love the world', format('title must be "Love the world", %s', selected_article->>'title');