From 9fdb86c4cf5fca8b9926ba5ff1b8bf1085957366 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Toma=C5=BE=20Jerman?= <tomaz.jerman121@gmail.com>
Date: Wed, 14 Sep 2022 19:23:04 +0200
Subject: [PATCH] Add date_format to supported QL functions

---
 pkg/dal/runner_gval.go         |  6 ++++++
 pkg/expr/func_time.go          | 20 +-------------------
 pkg/gvalfnc/time.go            | 18 ++++++++++++++++++
 store/adapters/rdbms/ql/ref.go |  5 +++++
 4 files changed, 30 insertions(+), 19 deletions(-)

diff --git a/pkg/dal/runner_gval.go b/pkg/dal/runner_gval.go
index fdb270b83..a887c7b61 100644
--- a/pkg/dal/runner_gval.go
+++ b/pkg/dal/runner_gval.go
@@ -166,6 +166,11 @@ var (
 				return fmt.Sprintf("date(%s)", args[0])
 			},
 		},
+		"date_format": {
+			Handler: func(args ...string) string {
+				return fmt.Sprintf("strftime(%s, %s)", args[0], args[1])
+			},
+		},
 
 		// generic stuff
 		"null": {
@@ -270,6 +275,7 @@ func newGval(expr string) (gval.Evaluable, error) {
 		gval.Function("quarter", gvalfnc.Quarter),
 		gval.Function("year", gvalfnc.Year),
 		gval.Function("month", gvalfnc.Month),
+		gval.Function("strftime", gvalfnc.StrfTime),
 		gval.Function("date", gvalfnc.Date),
 		gval.Function("isNil", gvalfnc.IsNil),
 		gval.Function("float", gvalfnc.CastFloat),
diff --git a/pkg/expr/func_time.go b/pkg/expr/func_time.go
index 11998fee2..9e4e35ce0 100644
--- a/pkg/expr/func_time.go
+++ b/pkg/expr/func_time.go
@@ -6,7 +6,6 @@ import (
 
 	"github.com/PaesslerAG/gval"
 	"github.com/cortezaproject/corteza-server/pkg/gvalfnc"
-	"github.com/lestrrat-go/strftime"
 )
 
 func TimeFunctions() []gval.Language {
@@ -20,7 +19,7 @@ func TimeFunctions() []gval.Language {
 		gval.Function("modMonth", modMonth),
 		gval.Function("modYear", modYear),
 		gval.Function("parseDuration", time.ParseDuration),
-		gval.Function("strftime", strfTime),
+		gval.Function("strftime", gvalfnc.StrfTime),
 		gval.Function("isLeapYear", isLeapYear),
 		gval.Function("now", now),
 		gval.Function("isWeekDay", isWeekDay),
@@ -163,23 +162,6 @@ func modYear(base interface{}, mod interface{}) (*time.Time, error) {
 	return &tmp, nil
 }
 
-// Strftime formats time with POSIX standard format
-// More details here:
-// https://github.com/lestrrat-go/strftime#supported-conversion-specifications
-func strfTime(base interface{}, f string) (string, error) {
-	t, _, err := gvalfnc.PrepMod(base, 0)
-
-	if err != nil {
-		return "", err
-	}
-
-	o, _ := strftime.Format(f, *t,
-		strftime.WithMilliseconds('b'),
-		strftime.WithUnixSeconds('L'))
-
-	return o, nil
-}
-
 // sub returns difference between two date into milliseconds
 func sub(from interface{}, to interface{}) (out int64, err error) {
 	t1, _, err := gvalfnc.PrepMod(from, 0)
diff --git a/pkg/gvalfnc/time.go b/pkg/gvalfnc/time.go
index ee166c833..8f5ae39a9 100644
--- a/pkg/gvalfnc/time.go
+++ b/pkg/gvalfnc/time.go
@@ -4,6 +4,7 @@ import (
 	"errors"
 	"time"
 
+	"github.com/lestrrat-go/strftime"
 	"github.com/spf13/cast"
 )
 
@@ -76,3 +77,20 @@ func PrepMod(base interface{}, mod interface{}) (*time.Time, int, error) {
 
 	return t, m, nil
 }
+
+// Strftime formats time with POSIX standard format
+// More details here:
+// https://github.com/lestrrat-go/strftime#supported-conversion-specifications
+func StrfTime(base interface{}, f string) (string, error) {
+	t, _, err := PrepMod(base, 0)
+
+	if err != nil {
+		return "", err
+	}
+
+	o, _ := strftime.Format(f, *t,
+		strftime.WithMilliseconds('b'),
+		strftime.WithUnixSeconds('L'))
+
+	return o, nil
+}
diff --git a/store/adapters/rdbms/ql/ref.go b/store/adapters/rdbms/ql/ref.go
index b95d2784a..fb4372e0d 100644
--- a/store/adapters/rdbms/ql/ref.go
+++ b/store/adapters/rdbms/ql/ref.go
@@ -176,6 +176,11 @@ var (
 		//},
 
 		// - filtering
+		"date_format": {
+			Handler: func(args ...exp.Expression) exp.Expression {
+				return exp.NewSQLFunctionExpression("DATE_FORMAT", args[0], args[1])
+			},
+		},
 		"now": {
 			Handler: func(args ...exp.Expression) exp.Expression {
 				return exp.NewSQLFunctionExpression("NOW")