feat: add Converters::EnumArray

Author: vladfaust

spec/converters/enum_array_spec.cr

@@ -0,0 +1,26 @@
+require "../../spec_helper"
+require "../../../src/core/converters/enum_array"
+
+require "pg"
+
+db = DB.open(ENV["DATABASE_URL"] || raise "No DATABASE_URL is set!")
+
+enum EnumArraySpecEnum
+  Foo
+  Bar
+  Baz
+end
+
+describe Core::Converters::EnumArray do
+  db.query_each("SELECT * FROM enum_arrays") do |rs|
+    it "returns array of enums from existing values" do
+      converted = Core::Converters::EnumArray(EnumArraySpecEnum, Int16).from_rs(rs)
+      converted.should eq [EnumArraySpecEnum::Bar, EnumArraySpecEnum::Baz]
+    end
+
+    it "returns Nil for NULL value" do
+      converted = Core::Converters::EnumArray(EnumArraySpecEnum, Int32).from_rs(rs)
+      converted.should be_nil
+    end
+  end
+end

spec/migration.sql

@@ -4,13 +4,15 @@ DROP TABLE IF EXISTS posts;
 DROP TABLE IF EXISTS users;
 DROP TABLE IF EXISTS pg_numeric;
 DROP TABLE IF EXISTS enums;
+DROP TABLE IF EXISTS enum_arrays;
 
 CREATE TABLE users(
   id          SERIAL PRIMARY KEY,
   referrer_id INT                     REFERENCES users (id),
   active      BOOL          NOT NULL  DEFAULT true,
   role        INT           NOT NULL  DEFAULT 0,
   name        VARCHAR(100)  NOT NULL,
+  permissions SMALLINT[]    NOT NULL  DEFAULT '{0}',
   created_at  TIMESTAMPTZ   NOT NULL  DEFAULT NOW(),
   updated_at  TIMESTAMPTZ
 );
@@ -38,3 +40,10 @@ CREATE TABLE enums(
 );
 
 INSERT INTO enums (foo, bar) VALUES (1, NULL);
+
+CREATE TABLE enum_arrays(
+  foo SMALLINT[] NOT NULL,
+  bar INT[]
+);
+
+INSERT INTO enum_arrays (foo, bar) VALUES ('{1,2}', NULL);

spec/repository_spec.cr

@@ -6,6 +6,7 @@ require "../src/core/repository"
 require "../src/core/schema"
 require "../src/core/query"
 require "../src/core/converters/enum"
+require "../src/core/converters/enum_array"
 require "../src/core/logger/io"
 
 alias Repo = Core::Repository
@@ -24,6 +25,11 @@ module RepoSpec
       Admin
     end
 
+    enum Permission
+      CreatePosts
+      EditPosts
+    end
+
     schema :users do
       primary_key :id
 
@@ -36,6 +42,7 @@ module RepoSpec
       field :active, Bool, db_default: true
       field :role, Role, default: Role::User, converter: Core::Converters::Enum(Role)
       field :name, String
+      field :permissions, Array(Permission), converter: Core::Converters::EnumArray(Permission, Int16), db_default: true
 
       field :created_at, Time, db_default: true
       field :updated_at, Time?
@@ -118,6 +125,7 @@ module RepoSpec
         user.active.should be_true
         user.role.should eq(User::Role::User)
         user.name.should eq("Test User")
+        user.permissions.should eq [User::Permission::CreatePosts]
         user.created_at.should be_a(Time)
         user.updated_at.should eq(nil)
       end
@@ -225,11 +233,10 @@ module RepoSpec
     end
 
     context "with Query instance" do
-      update = repo.update(User.where(id: user.id).set(name: "Updated Again User"))
-      updated_user = repo.query_one(User.last)
-
       it do
-        updated_user.name.should eq "Updated Again User"
+        update = repo.update(User.where(id: user.id).set(permissions: [User::Permission::CreatePosts, User::Permission::EditPosts]))
+        updated_user = repo.query_one(User.last)
+        updated_user.permissions.should eq [User::Permission::CreatePosts, User::Permission::EditPosts]
       end
     end
   end

src/core/converters/enum_array.cr

@@ -0,0 +1,43 @@
+require "../../converter"
+
+module Core
+  module Converters
+    # Allows to represent integer array values as Array of Enums in models. You must specify which `Int` you use in the database schema (e.g. `SMALLINT` stays for `Int16`, `INT` for `Int32`).
+    #
+    # TODO: Remove obstructing `IntClass` requirement. See https://github.com/will/crystal-pg/issues/150
+    #
+    # ```
+    # # SQL:
+    # # table users
+    # #   column role SMALLINT[]
+    #
+    # require "core/converters/enum_array"
+    #
+    # class User
+    #   include Core::Schema
+    #
+    #   enum Permission
+    #     CreatePosts
+    #     EditPosts
+    #   end
+    #
+    #   schema do
+    #     field :permissions, Array(Permission), converter: Core::Converters::EnumArray(Permission, Int16)
+    #   end
+    # end
+    #
+    # user.permissions # => [User::Permission::CreatePosts]
+    # user.insert      # => INSERT INTO users (permissions) VALUES('{1}')
+    # ```
+    class EnumArray(EnumClass, IntClass) < Converter(Array(Enum))
+      def self.from_rs(rs)
+        values = rs.read(Array(IntClass) | Nil)
+        values.try &.map { |v| EnumClass.new(v.to_i32) }
+      end
+
+      def self.to_db(enum _enum : Array(EnumClass))
+        _enum.map(&.value)
+      end
+    end
+  end
+end

src/core/query/instance/set.cr

@@ -34,7 +34,15 @@ struct Core::Query::Instance(Schema)
         case key
         {% for field in Schema::INTERNAL__CORE_FIELDS %}
           when {{field[:name]}}
-            set({{field[:key].id.stringify}} + " = ?", value)
+            {% if field[:converter] %}
+              if value.is_a?({{field[:type]}})
+                set({{field[:key].id.stringify}} + " = ?", {{field[:converter].id}}.to_db(value))
+              end
+            {% else %}
+              if value.is_a?({{field[:type]}})
+                set({{field[:key].id.stringify}} + " = ?", value)
+              end
+            {% end %}
         {% end %}
         else
           raise ArgumentError.new("Invalid field name #{key} for #{Schema}!")
@@ -49,7 +57,7 @@ struct Core::Query::Instance(Schema)
   macro append_set_clauses
     if set_clauses.any?
       query += " SET " + set_clauses.map(&.[:clause]).join(", ")
-      params.concat(set_clauses.map(&.[:params]).flatten.compact)
+      params.concat(set_clauses.map(&.[:params]).flat_map(&.itself).compact)
     end
   end
 end

src/core/schema/fields.cr

@@ -48,7 +48,7 @@ module Core
       {%
         converter = if options[:converter]
                       if options[:converter].is_a?(Generic)
-                        (options[:converter].name.resolve.stringify.gsub(/\(\w+\)/, "(" + options[:converter].type_vars.first.resolve.stringify + ")")).id
+                        (options[:converter].name.resolve.stringify.gsub(/\([\w, ]+\)/, "(" + options[:converter].type_vars.map { |v| v.resolve.stringify }.join(", ") + ")")).id
                       else
                         options[:converter]
                       end
@@ -60,7 +60,13 @@ module Core
       {% INTERNAL__CORE_FIELDS.push({
            name: name,
            type: (if _type.is_a?(Generic)
-             _type
+             if ("#{_type.name.resolve}" == "Array(T)")
+               _type.name.resolve.stringify.gsub(/\([\w, ]+\)/, "(" + _type.type_vars.map do |v|
+                 v.resolve.stringify
+               end.join(", ") + ")").id
+             else
+               _type
+             end
            else
              _type.resolve
            end),

src/core/schema/getters.cr

@@ -43,7 +43,7 @@ module Core
                 %}
                 \{{field[:name]}} => \{{val.id}},
               \{% end %}
-            } of Symbol => \{{INTERNAL__CORE_FIELDS.map(&.[:type]).join(" | ").id}}
+            } of Symbol => Core::Param
           end
         \{% end %}