From 304df6ac42e93235f3c14518f87ea47f834cde59 Mon Sep 17 00:00:00 2001
From: Nick Franken <shnick@gmail.com>
Date: Tue, 21 Feb 2017 15:26:32 -0600
Subject: [PATCH 1/7] aggregate working, just need to write more tests

---
 .crystal-version                        |  2 +-
 spec/repo_spec.cr                       | 15 +++++++++++++++
 src/crecto/adapters/mysql_adapter.cr    | 24 ++++++++++++++++++++++++
 src/crecto/adapters/postgres_adapter.cr | 24 ++++++++++++++++++++++++
 src/crecto/repo.cr                      | 16 +++++++++++++++-
 5 files changed, 79 insertions(+), 2 deletions(-)

diff --git a/.crystal-version b/.crystal-version
index 144996e..1db0ede 100644
--- a/.crystal-version
+++ b/.crystal-version
@@ -1 +1 @@
-0.20.3
+0.21.0
\ No newline at end of file
diff --git a/spec/repo_spec.cr b/spec/repo_spec.cr
index 59c47c9..02b64b3 100644
--- a/spec/repo_spec.cr
+++ b/spec/repo_spec.cr
@@ -125,6 +125,21 @@ describe Crecto do
       end
     end
 
+    describe "#aggregate" do
+      it "should do things" do
+        x = Crecto::Repo.aggregate(User, :sum, :id)
+        puts x
+        puts x.class
+      end
+
+      it "should do more things" do
+        query = Crecto::Repo::Query.where(name: "test")
+        x = Crecto::Repo.aggregate(User, :count, :id, query)
+        puts x
+        puts x.class
+      end
+    end
+
     describe "#get" do
       it "should return a user" do
         now = Time.now
diff --git a/src/crecto/adapters/mysql_adapter.cr b/src/crecto/adapters/mysql_adapter.cr
index 6dbd854..459e261 100644
--- a/src/crecto/adapters/mysql_adapter.cr
+++ b/src/crecto/adapters/mysql_adapter.cr
@@ -60,6 +60,26 @@ module Crecto
         end
       end
 
+      def self.aggregate(queryable, ag, field)
+        @@CRECTO_DB = DB.open(ENV["MYSQL_URL"]) if @@CRECTO_DB.nil?
+        @@CRECTO_DB.as(DB::Database).scalar(build_aggregate_query(queryable, ag, field))
+      end
+
+      def self.aggregate(queryable, ag, field, query : Crecto::Repo::Query)
+        @@CRECTO_DB = DB.open(ENV["MYSQL_URL"]) if @@CRECTO_DB.nil?
+
+        params = [] of DbValue | Array(DbValue)
+        q = [build_aggregate_query(queryable, ag, field)]
+        q.push joins(queryable, query, params) if query.joins.any?
+        q.push wheres(queryable, query, params) if query.wheres.any?
+        q.push or_wheres(queryable, query, params) if query.or_wheres.any?
+        q.push order_bys(query) if query.order_bys.any?
+        q.push limit(query) unless query.limit.nil?
+        q.push offset(query) unless query.offset.nil?
+
+        @@CRECTO_DB.as(DB::Database).scalar(q.join(" "), params)
+      end
+
       def self.execute_query(query_string, params)
         @@CRECTO_DB = DB.open(ENV["MYSQL_URL"]) if @@CRECTO_DB.nil?
         @@CRECTO_DB.as(DB::Database).query(query_string, params)
@@ -89,6 +109,10 @@ module Crecto
         execute_query(q.join(" "), [id])
       end
 
+      private def self.build_aggregate_query(queryable, ag, field)
+        "SELECT #{ag}(#{field}) from #{queryable.table_name}"
+      end
+
       private def self.all(queryable, query)
         params = [] of DbValue | Array(DbValue)
 
diff --git a/src/crecto/adapters/postgres_adapter.cr b/src/crecto/adapters/postgres_adapter.cr
index c55af8c..7c20032 100644
--- a/src/crecto/adapters/postgres_adapter.cr
+++ b/src/crecto/adapters/postgres_adapter.cr
@@ -60,6 +60,26 @@ module Crecto
         end
       end
 
+      def self.aggregate(queryable, ag, field)
+        @@CRECTO_DB = DB.open(ENV["PG_URL"]) if @@CRECTO_DB.nil?
+        @@CRECTO_DB.as(DB::Database).scalar(build_aggregate_query(queryable, ag, field))
+      end
+
+      def self.aggregate(queryable, ag, field, query : Crecto::Repo::Query)
+        @@CRECTO_DB = DB.open(ENV["PG_URL"]) if @@CRECTO_DB.nil?
+        params = [] of DbValue | Array(DbValue)
+        
+        q = [build_aggregate_query(queryable, ag, field)]
+        q.push joins(queryable, query, params) if query.joins.any?
+        q.push wheres(queryable, query, params) if query.wheres.any?
+        q.push or_wheres(queryable, query, params) if query.or_wheres.any?
+        q.push order_bys(query) if query.order_bys.any?
+        q.push limit(query) unless query.limit.nil?
+        q.push offset(query) unless query.offset.nil?
+
+        @@CRECTO_DB.as(DB::Database).scalar(position_args(q.join(" ")), params)
+      end
+
       def self.execute(query_string, params)
         @@CRECTO_DB = DB.open(ENV["PG_URL"]) if @@CRECTO_DB.nil?
         @@CRECTO_DB.as(DB::Database).query(query_string, params)
@@ -79,6 +99,10 @@ module Crecto
         execute(q.join(" "), [id])
       end
 
+      private def self.build_aggregate_query(queryable, ag, field)
+        "SELECT #{ag}(#{field}) from #{queryable.table_name}"
+      end
+
       private def self.all(queryable, query)
         params = [] of DbValue | Array(DbValue)
 
diff --git a/src/crecto/repo.cr b/src/crecto/repo.cr
index fd44868..56ad78f 100644
--- a/src/crecto/repo.cr
+++ b/src/crecto/repo.cr
@@ -233,7 +233,7 @@ module Crecto
     # Repo.delete_all(User, query)
     # ```
     def self.delete_all(queryable, query = Query.new)
-      query = ADAPTER.run(:delete_all, queryable, query)
+      ADAPTER.run(:delete_all, queryable, query)
     end
 
     # Run aribtrary sql queries. `query` will cast the output as that
@@ -263,6 +263,20 @@ module Crecto
       ADAPTER.run(:sql, sql, params).as(DB::ResultSet)
     end
 
+    # Calculate the given aggregate `ag` over the given `field`
+    # Aggregate `ag` must be one of (:avg, :count, :max, :min:, :sum)
+    def self.aggregate(queryable, ag : Symbol, field : Symbol | String)
+      raise InvalidOption.new("Aggregate must be one of :avg, :count, :max, :min:, :sum") unless [:avg, :count, :max, :min, :sum].includes?(ag)
+
+      ADAPTER.aggregate(queryable, ag, field)
+    end
+
+    def self.aggregate(queryable, ag : Symbol, field : Symbol | String, query : Crecto::Repo::Query)
+      raise InvalidOption.new("Aggregate must be one of :avg, :count, :max, :min:, :sum") unless [:avg, :count, :max, :min, :sum].includes?(ag)
+
+      ADAPTER.aggregate(queryable, ag, field, query)
+    end
+
     private def self.add_preloads(results, queryable, preloads)
       preloads.each do |preload|
         case queryable.association_type_for_association(preload)

From 9495751baf2a37cbbc7ac0b2352a3afb8b98d565 Mon Sep 17 00:00:00 2001
From: Nick Franken <shnick@gmail.com>
Date: Tue, 21 Feb 2017 15:28:59 -0600
Subject: [PATCH 2/7] use crystal-pg master for now

---
 shard.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/shard.yml b/shard.yml
index 4010e54..e4d4198 100644
--- a/shard.yml
+++ b/shard.yml
@@ -18,4 +18,4 @@ development_dependencies:
 
   pg:
     github: will/crystal-pg
-    version: 0.13.1
\ No newline at end of file
+    branch: master
\ No newline at end of file

From a725592ee6060c69af3375ceea029011bd7d6ed3 Mon Sep 17 00:00:00 2001
From: Nick Franken <shnick@gmail.com>
Date: Tue, 21 Feb 2017 15:43:42 -0600
Subject: [PATCH 3/7] tests init, updated readme to include aggregate
 functions, updated shard to use latest crystal-pg

---
 README.md          |  7 +++++++
 shard.yml          |  2 +-
 spec/repo_spec.cr  | 49 +++++++++++++++++++++++++++++++++++++---------
 src/crecto/repo.cr |  4 ++--
 4 files changed, 50 insertions(+), 12 deletions(-)

diff --git a/README.md b/README.md
index 06d7961..540d4d1 100644
--- a/README.md
+++ b/README.md
@@ -169,6 +169,13 @@ users[0].posts # has_many relation is preloaded
 
 posts = Crecto::Repo.all(Post, Crecto::Query.new, preload: [:user])
 posts[0].user # belongs_to relation preloaded
+
+#
+# Aggregate functions
+#
+# can use the following aggregate functions: :avg, :count, :max, :min:, :sum
+Crecto::Repo.aggregate(User, :count, :id)
+Crecto::Repo.aggregate(User, :avg, :age, Crecto::Repo::Query.where(name: 'Bill'))
 ```
 
 ## Contributing
diff --git a/shard.yml b/shard.yml
index e4d4198..27493e1 100644
--- a/shard.yml
+++ b/shard.yml
@@ -18,4 +18,4 @@ development_dependencies:
 
   pg:
     github: will/crystal-pg
-    branch: master
\ No newline at end of file
+    version: 0.13.2 
\ No newline at end of file
diff --git a/spec/repo_spec.cr b/spec/repo_spec.cr
index 02b64b3..54fe0f3 100644
--- a/spec/repo_spec.cr
+++ b/spec/repo_spec.cr
@@ -126,17 +126,48 @@ describe Crecto do
     end
 
     describe "#aggregate" do
-      it "should do things" do
-        x = Crecto::Repo.aggregate(User, :sum, :id)
-        puts x
-        puts x.class
+      describe "without a query" do
+        pending "should return the correct :avg" do
+          
+        end
+
+        pending "should return the correct :count" do
+          
+        end
+
+        pending "should return the correct :max" do
+          
+        end
+
+        pending "should return the correct :min" do
+          
+        end
+
+        pending "should return the correct :sum" do
+          
+        end
       end
 
-      it "should do more things" do
-        query = Crecto::Repo::Query.where(name: "test")
-        x = Crecto::Repo.aggregate(User, :count, :id, query)
-        puts x
-        puts x.class
+      describe "with a query" do
+        pending "should return the correct :avg" do
+          
+        end
+
+        pending "should return the correct :count" do
+          
+        end
+
+        pending "should return the correct :max" do
+          
+        end
+
+        pending "should return the correct :min" do
+          
+        end
+
+        pending "should return the correct :sum" do
+          
+        end
       end
     end
 
diff --git a/src/crecto/repo.cr b/src/crecto/repo.cr
index 56ad78f..1c53696 100644
--- a/src/crecto/repo.cr
+++ b/src/crecto/repo.cr
@@ -265,13 +265,13 @@ module Crecto
 
     # Calculate the given aggregate `ag` over the given `field`
     # Aggregate `ag` must be one of (:avg, :count, :max, :min:, :sum)
-    def self.aggregate(queryable, ag : Symbol, field : Symbol | String)
+    def self.aggregate(queryable, ag : Symbol, field : Symbol)
       raise InvalidOption.new("Aggregate must be one of :avg, :count, :max, :min:, :sum") unless [:avg, :count, :max, :min, :sum].includes?(ag)
 
       ADAPTER.aggregate(queryable, ag, field)
     end
 
-    def self.aggregate(queryable, ag : Symbol, field : Symbol | String, query : Crecto::Repo::Query)
+    def self.aggregate(queryable, ag : Symbol, field : Symbol, query : Crecto::Repo::Query)
       raise InvalidOption.new("Aggregate must be one of :avg, :count, :max, :min:, :sum") unless [:avg, :count, :max, :min, :sum].includes?(ag)
 
       ADAPTER.aggregate(queryable, ag, field, query)

From ccfc4acfc778a0c3d1882e7e0838b973bb4bb398 Mon Sep 17 00:00:00 2001
From: Nick Franken <shnick@gmail.com>
Date: Tue, 21 Feb 2017 18:01:52 -0600
Subject: [PATCH 4/7] aggregate done

---
 spec/helper_methods.cr                  |  12 +++
 spec/repo_spec.cr                       | 111 +++++++++++++++++++-----
 src/crecto/adapters/postgres_adapter.cr |   1 -
 src/crecto/model.cr                     |   3 +-
 4 files changed, 104 insertions(+), 23 deletions(-)
 create mode 100644 spec/helper_methods.cr

diff --git a/spec/helper_methods.cr b/spec/helper_methods.cr
new file mode 100644
index 0000000..f1ab1f4
--- /dev/null
+++ b/spec/helper_methods.cr
@@ -0,0 +1,12 @@
+def quick_create_user(name)
+  user = User.new
+  user.name = name
+  Crecto::Repo.insert(user).instance
+end
+
+def quick_create_user_with_things(name, things)
+  user = User.new
+  user.name = name
+  user.things = things
+  Crecto::Repo.insert(user).instance
+end
diff --git a/spec/repo_spec.cr b/spec/repo_spec.cr
index 54fe0f3..7cd7dfe 100644
--- a/spec/repo_spec.cr
+++ b/spec/repo_spec.cr
@@ -1,4 +1,5 @@
 require "./spec_helper"
+require "./helper_methods"
 
 describe Crecto do
   describe "Repo" do
@@ -127,46 +128,116 @@ describe Crecto do
 
     describe "#aggregate" do
       describe "without a query" do
-        pending "should return the correct :avg" do
-          
+        it "should return the correct :avg" do
+          Crecto::Repo.delete_all(Post)
+          Crecto::Repo.delete_all(User)
+          quick_create_user_with_things("test", 9)
+          quick_create_user_with_things("test", 10)
+          quick_create_user_with_things("test", 11)
+
+          Crecto::Repo.aggregate(User, :avg, :things).as(PG::Numeric).to_f.should eq 10.0
         end
 
-        pending "should return the correct :count" do
-          
+        it "should return the correct :count" do
+          Crecto::Repo.delete_all(Post)
+          Crecto::Repo.delete_all(User)
+          quick_create_user_with_things("test", 9)
+          quick_create_user_with_things("test", 10)
+          quick_create_user_with_things("test", 11)
+
+          Crecto::Repo.aggregate(User, :count, :id).should eq 3
         end
 
-        pending "should return the correct :max" do
-          
+        it "should return the correct :max" do
+          Crecto::Repo.delete_all(Post)
+          Crecto::Repo.delete_all(User)
+          quick_create_user_with_things("test", 9)
+          quick_create_user_with_things("test", 10)
+          quick_create_user_with_things("test", 11)
+
+          Crecto::Repo.aggregate(User, :max, :things).should eq 11
         end
 
-        pending "should return the correct :min" do
-          
+        it "should return the correct :min" do
+          Crecto::Repo.delete_all(Post)
+          Crecto::Repo.delete_all(User)
+          quick_create_user_with_things("test", 9)
+          quick_create_user_with_things("test", 10)
+          quick_create_user_with_things("test", 11)
+
+          Crecto::Repo.aggregate(User, :min, :things).should eq 9
         end
 
-        pending "should return the correct :sum" do
-          
+        it "should return the correct :sum" do
+          Crecto::Repo.delete_all(Post)
+          Crecto::Repo.delete_all(User)
+          quick_create_user_with_things("test", 9)
+          quick_create_user_with_things("test", 10)
+          quick_create_user_with_things("test", 11)
+
+          Crecto::Repo.aggregate(User, :sum, :things).should eq 30
         end
       end
 
       describe "with a query" do
-        pending "should return the correct :avg" do
-          
+        it "should return the correct :avg" do
+          Crecto::Repo.delete_all(Post)
+          Crecto::Repo.delete_all(User)
+          quick_create_user_with_things("test", 9)
+          quick_create_user_with_things("test", 10)
+          quick_create_user_with_things("test", 11)
+          quick_create_user_with_things("nope", 12)
+          query = Crecto::Repo::Query.where(name: "test")
+
+          Crecto::Repo.aggregate(User, :avg, :things, query).as(PG::Numeric).to_f.should eq 10.0
         end
 
-        pending "should return the correct :count" do
-          
+        it "should return the correct :count" do
+          Crecto::Repo.delete_all(Post)
+          Crecto::Repo.delete_all(User)
+          quick_create_user_with_things("test", 9)
+          quick_create_user_with_things("test", 10)
+          quick_create_user_with_things("test", 11)
+          quick_create_user_with_things("nope", 12)
+          query = Crecto::Repo::Query.where(name: "test")
+
+          Crecto::Repo.aggregate(User, :count, :id, query).should eq 3
         end
 
-        pending "should return the correct :max" do
-          
+        it "should return the correct :max" do
+          Crecto::Repo.delete_all(Post)
+          Crecto::Repo.delete_all(User)
+          quick_create_user_with_things("test", 9)
+          quick_create_user_with_things("test", 10)
+          quick_create_user_with_things("test", 11)
+          quick_create_user_with_things("nope", 12)
+          query = Crecto::Repo::Query.where(name: "test")
+
+          Crecto::Repo.aggregate(User, :max, :things, query).should eq 11
         end
 
-        pending "should return the correct :min" do
-          
+        it "should return the correct :min" do
+          Crecto::Repo.delete_all(Post)
+          Crecto::Repo.delete_all(User)
+          quick_create_user_with_things("test", 9)
+          quick_create_user_with_things("test", 10)
+          quick_create_user_with_things("test", 11)
+          quick_create_user_with_things("nope", 12)
+          query = Crecto::Repo::Query.where(name: "test")
+
+          Crecto::Repo.aggregate(User, :min, :things, query).should eq 9
         end
 
-        pending "should return the correct :sum" do
-          
+        it "should return the correct :sum" do
+          Crecto::Repo.delete_all(Post)
+          Crecto::Repo.delete_all(User)
+          quick_create_user_with_things("test", 9)
+          quick_create_user_with_things("test", 10)
+          quick_create_user_with_things("test", 11)
+          quick_create_user_with_things("nope", 12)
+          query = Crecto::Repo::Query.where(name: "test")
+
+          Crecto::Repo.aggregate(User, :sum, :things, query).should eq 30
         end
       end
     end
diff --git a/src/crecto/adapters/postgres_adapter.cr b/src/crecto/adapters/postgres_adapter.cr
index 7c20032..2f2673b 100644
--- a/src/crecto/adapters/postgres_adapter.cr
+++ b/src/crecto/adapters/postgres_adapter.cr
@@ -68,7 +68,6 @@ module Crecto
       def self.aggregate(queryable, ag, field, query : Crecto::Repo::Query)
         @@CRECTO_DB = DB.open(ENV["PG_URL"]) if @@CRECTO_DB.nil?
         params = [] of DbValue | Array(DbValue)
-        
         q = [build_aggregate_query(queryable, ag, field)]
         q.push joins(queryable, query, params) if query.joins.any?
         q.push wheres(queryable, query, params) if query.wheres.any?
diff --git a/src/crecto/model.cr b/src/crecto/model.cr
index c50564e..e922d36 100644
--- a/src/crecto/model.cr
+++ b/src/crecto/model.cr
@@ -1,6 +1,5 @@
 module Crecto
-
-  #Your data models should extend `Crecto::Model`:
+  # Your data models should extend `Crecto::Model`:
   #
   # `class User < Crecto::Model`
   #  -or-

From d6f72edc4cff65f8873b83f41811e54a783a20d3 Mon Sep 17 00:00:00 2001
From: Nick Franken <shnick@gmail.com>
Date: Tue, 21 Feb 2017 18:13:35 -0600
Subject: [PATCH 5/7] dynamic helper method

---
 spec/helper_methods.cr | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/spec/helper_methods.cr b/spec/helper_methods.cr
index f1ab1f4..dde2fc4 100644
--- a/spec/helper_methods.cr
+++ b/spec/helper_methods.cr
@@ -4,9 +4,11 @@ def quick_create_user(name)
   Crecto::Repo.insert(user).instance
 end
 
-def quick_create_user_with_things(name, things)
+{% for x in ["things", "nope", "yep", "some_date", "pageviews"] %}
+def quick_create_user_with_{{x.id}}(name, {{x.id}})
   user = User.new
   user.name = name
-  user.things = things
+  user.{{x.id}} = {{x.id}}
   Crecto::Repo.insert(user).instance
 end
+{% end %}

From ce33361e4883efcee9ff732149fbcd47ce5f9246 Mon Sep 17 00:00:00 2001
From: Nick Franken <shnick@gmail.com>
Date: Tue, 21 Feb 2017 18:22:20 -0600
Subject: [PATCH 6/7] added test case for error

---
 README.md         | 1 +
 spec/repo_spec.cr | 6 ++++++
 2 files changed, 7 insertions(+)

diff --git a/README.md b/README.md
index 540d4d1..ff9fd5c 100644
--- a/README.md
+++ b/README.md
@@ -61,6 +61,7 @@ require "crecto"
 - [ ] Transactions / Multi
 - [ ] Association / dependent options (`dependent: :delete_all`, `dependent: :nilify_all`, etc)
 - [ ] Unique constraint
+- [ ] Combine database adapters (base class). Currently there is unecessary duplication
 
 ## Usage
 
diff --git a/spec/repo_spec.cr b/spec/repo_spec.cr
index 7cd7dfe..f2a85c7 100644
--- a/spec/repo_spec.cr
+++ b/spec/repo_spec.cr
@@ -127,6 +127,12 @@ describe Crecto do
     end
 
     describe "#aggregate" do
+      it "should raise InvalidOption with an invalid option" do
+        expect_raises Crecto::InvalidOption do
+          Crecto::Repo.aggregate(User, :blurb, :id)
+        end
+      end
+
       describe "without a query" do
         it "should return the correct :avg" do
           Crecto::Repo.delete_all(Post)

From ee8eb3ce72a1cf05f519e7dff79bfe4d0cc2a3bd Mon Sep 17 00:00:00 2001
From: Nick Franken <shnick@gmail.com>
Date: Tue, 21 Feb 2017 18:34:37 -0600
Subject: [PATCH 7/7] explicit json require, necessary for mysql users

---
 src/crecto.cr | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/crecto.cr b/src/crecto.cr
index b117257..f19ec52 100644
--- a/src/crecto.cr
+++ b/src/crecto.cr
@@ -1,3 +1,4 @@
+require "json"
 require "./crecto/errors/*"
 require "./crecto/schema/*"
 require "./crecto/adapters/*"