rebar3_sqlc

rebar3 plugin for compiling .sql SQL modules to Erlang modules.

Use

Add the plugin to your rebar3 config:

 {plugins, [rebar3_sqlc]}.
{provider_hooks, [
{pre, [
{compile, {sqlc, compile}},
{clean, {sqlc, clean}}
]}
]}.

Then create your SQL module file inside your project's src/ directory, for example as src/my_app_queries.sql

query user_by_id(:id uuid) returns user asselect user_id as id, name, avatar_url, registered_at
from user
where user_id = :id;
mutation update_user(:id uuid, :updates jsonb) returns user asupdate user
set
name = case when :updates ? 'name' then :updates ->>'name' else user.name end,
avatar_url = case when :updates ? 'avatarUrl' then :updates ->>'avatarUrl' else user.avatar_url end
where user_id = :id
returning user_id AS id, name, avatar_url, registered_at;

The SQL module above would produce an erlang module with 2 functions:

%% @private
-module(my_app_queries).
-export([
user_by_id/1,
update_user/1
]).
user_by_id(#{id :=Id}) ->
#{
type=>query,
name=> {my_app_queries, user_by_id},
statement=> [
<<
"select user_id as id, name, avatar_url, registered_at\n",
" from user\n",
" where user_id = "
>>, {parameter, #{key=> {my_app_queries, user_by_id, id}, value=>Id, type=> <<"uuid">>}}
]
}.
update_user(#{id :=Id, updates :=Updates}) ->
#{
type=>mutation,
name=> {my_app_queries, update_user},
statement=> [
<<"update user\n set\n name = case ""when ">>,
{parameter,
#{key=> {my_app_queries, update_user, updates}, value=>Updates,
type=> <<"jsonb">>}},
<<" ? 'name' then ">>,
{parameter,
#{key=> {my_app_queries, update_user, updates}, value=>Updates,
type=> <<"jsonb">>}},
<<" ->> 'name' else user.name end,\n avatar_url = case when ">>,
{parameter,
#{key=> {my_app_queries, update_user, updates}, value=>Updates,
type=> <<"jsonb">>}},
<<" ? 'avatarUrl' then ">>,
{parameter,
#{key=> {my_app_queries, update_user, updates}, value=>Updates,
type=> <<"jsonb">>}},
<<" ->> 'avatarUrl' else user.avatar_url ">>,
"end\n where user_id = ">>,
{parameter,
#{key=> {my_app_queries, update_user, id}, value=>Id,
type=> <<"uuid">>}},
<<"\n returning user_id AS id, name, avatar_url, registered_at">>
]
}.