Create find_follow.sql

src/main/resources/sql/functions/follow/find_follow.sql

@@ -0,0 +1,25 @@
+create or replace function find_follow(
+    _target_id uuid,
+    _citizen_id uuid,
+    out resource json,
+    out following boolean
+) language plpgsql as
+$$
+begin
+    select to_json(t)
+    into resource
+    from (
+        select
+            f.*,
+            json_build_object('id', f.target_id, 'reference', f.target_reference) as target,
+            find_citizen_by_id(f.created_by_id) as created_by
+        from follow as f
+        where f.created_by_id = _citizen_id
+          and f.target_id = _target_id
+    ) as t;
+
+    select resource is not null into following;
+end;
+$$;
+
+-- drop function if exists find_follow(uuid, uuid);

src/test/sql/follow.sql

@@ -25,6 +25,9 @@ declare
       "email":"george.michel2@gmail.com"
     }
     $json$;
+
+    created_article  json := '{"version_id":"933b6a1b-50c9-42b6-989f-c02a57814ef9", "title": "Love the world", "anonymous": false, "content": "bla bal bla", "tags": ["love", "test"], "draft":false}';
+    first_article_id uuid;
 begin
     -- insert user for context
     select insert_user(created_user) into created_user;
@@ -41,15 +44,27 @@ begin
 
 
     perform follow('citizen'::regclass, _citizen_id, _citizen_id2);
-    assert (select count(*) > 0 from follow), 'follow must be inserted';
+    assert (select count(*) = 1 from follow), 'follow must be inserted';
+    assert (select following = true from find_follow(_citizen_id, _citizen_id2)), 'find_follow must return the following';
 
     perform follow('citizen'::regclass, _citizen_id, _citizen_id2);
-    assert (select count(*) > 0 from follow), 'follow must be inserted';
+    assert (select count(*) = 1 from follow), 'follow must be inserted';
 
     perform unfollow('citizen'::regclass, _citizen_id, _citizen_id2);
     assert (select count(*) = 0 from follow), 'follow must be deleted after unfollow';
 
+    -- upsert article
+    created_article := jsonb_set(created_article::jsonb, '{created_by}'::text[], jsonb_build_object('id', _citizen_id::text), true)::json;
+    select upsert_article(created_article) into created_article;
+    first_article_id = (created_article->>'id')::uuid;
+
+    perform follow('article'::regclass, first_article_id, _citizen_id);
+    assert (select following = true from find_follow(first_article_id, _citizen_id)), 'find_follow must return the following';
+    assert (select following = false from find_follow(first_article_id, _citizen_id2)), 'find_follow must not return the following if not followinf';
+
     -- delete follow and context
+    delete from follow;
+    delete from article;
     delete from citizen;
     delete from "user";