From c5f4a5e8887f6cef7a800e2f775873c95478f58e Mon Sep 17 00:00:00 2001
From: Owen Rumney <owen@owenrumney.co.uk>
Date: Tue, 16 Nov 2021 11:39:16 +0000
Subject: [PATCH] Add support for comma string

- used in examples like severity=low,high
---
 decoder.go      | 14 ++++++++++++++
 decoder_test.go | 18 ++++++++++--------
 structs_test.go | 37 +++++++++++++++++++++++--------------
 3 files changed, 47 insertions(+), 22 deletions(-)

diff --git a/decoder.go b/decoder.go
index 5f7ddb6..7340ca6 100644
--- a/decoder.go
+++ b/decoder.go
@@ -214,6 +214,20 @@ func unmarshalField(
 			}
 
 			valueField.Set(slice)
+		} else {
+			str, ok := params[param]
+			if ok {
+				stringParts := strings.Split(str, ",")
+				slice := reflect.MakeSlice(typeField, len(stringParts), len(stringParts))
+
+				for i, p := range stringParts {
+					inVal := reflect.ValueOf(p)
+					asVal := inVal.Convert(typeField.Elem())
+					slice.Index(i).Set(asVal)
+				}
+
+				valueField.Set(slice)
+			}
 		}
 	}
 
diff --git a/decoder_test.go b/decoder_test.go
index 87fa487..b6355bf 100644
--- a/decoder_test.go
+++ b/decoder_test.go
@@ -23,14 +23,15 @@ func Test_UnmarshalRequest(t *testing.T) {
 					"id": "fake-scan-id",
 				},
 				QueryStringParameters: map[string]string{
-					"page":      "2",
-					"page_size": "30",
-					"const":     "two",
-					"bool":      "true",
-					"pbool1":    "0",
-					"time":      "2021-11-01T11:11:11.000Z",
-					"alias":     "hello",
-					"alias_ptr": "world",
+					"page":       "2",
+					"page_size":  "30",
+					"const":      "two",
+					"bool":       "true",
+					"pbool1":     "0",
+					"time":       "2021-11-01T11:11:11.000Z",
+					"alias":      "hello",
+					"alias_ptr":  "world",
+					"commaSplit": "one,two,three",
 				},
 				MultiValueQueryStringParameters: map[string][]string{
 					"terms":   []string{"one", "two"},
@@ -60,6 +61,7 @@ func Test_UnmarshalRequest(t *testing.T) {
 		assert.Equal(t, input.Alias, stringAliasExample("hello"))
 		assert.NotNil(t, input.AliasPtr)
 		assert.Equal(t, *input.AliasPtr, aliasExample)
+		assert.DeepEqual(t, []Number{numberOne, numberTwo, numberThree}, input.CommaSplit, "CommaSplit must have 2 items")
 		assert.Equal(t, (*bool)(nil), input.PBoolTwo, "PBoolTwo must be nil")
 		assert.DeepEqual(t, []string{"one", "two"}, input.Terms, "Terms must be parsed from multiple query params")
 		assert.DeepEqual(t, []float64{1.2, 3.5, 666.666}, input.Numbers, "Numbers must be parsed from multiple query params")
diff --git a/structs_test.go b/structs_test.go
index c4e7985..b2cde5d 100644
--- a/structs_test.go
+++ b/structs_test.go
@@ -9,21 +9,30 @@ const (
 	mockConstTwo mockConst = "two"
 )
 
+type Number string
+
+const (
+	numberOne   Number = "one"
+	numberTwo   Number = "two"
+	numberThree Number = "three"
+)
+
 type mockListRequest struct {
-	ID       string              `lambda:"path.id"`
-	Page     int64               `lambda:"query.page"`
-	PageSize int64               `lambda:"query.page_size"`
-	Terms    []string            `lambda:"query.terms"`
-	Numbers  []float64           `lambda:"query.numbers"`
-	Const    mockConst           `lambda:"query.const"`
-	Bool     bool                `lambda:"query.bool"`
-	PBoolOne *bool               `lambda:"query.pbool1"`
-	PBoolTwo *bool               `lambda:"query.pbool2"`
-	Time     *time.Time          `lambda:"query.time"`
-	Alias    stringAliasExample  `lambda:"query.alias"`
-	AliasPtr *stringAliasExample `lambda:"query.alias_ptr"`
-	Language string              `lambda:"header.Accept-Language"`
-	Encoding []string            `lambda:"header.Accept-Encoding"`
+	ID         string              `lambda:"path.id"`
+	Page       int64               `lambda:"query.page"`
+	PageSize   int64               `lambda:"query.page_size"`
+	Terms      []string            `lambda:"query.terms"`
+	Numbers    []float64           `lambda:"query.numbers"`
+	Const      mockConst           `lambda:"query.const"`
+	Bool       bool                `lambda:"query.bool"`
+	PBoolOne   *bool               `lambda:"query.pbool1"`
+	PBoolTwo   *bool               `lambda:"query.pbool2"`
+	Time       *time.Time          `lambda:"query.time"`
+	Alias      stringAliasExample  `lambda:"query.alias"`
+	AliasPtr   *stringAliasExample `lambda:"query.alias_ptr"`
+	CommaSplit []Number            `lambda:"query.commaSplit"`
+	Language   string              `lambda:"header.Accept-Language"`
+	Encoding   []string            `lambda:"header.Accept-Encoding"`
 }
 
 type mockGetRequest struct {