Merge pull request #8 from scrambledeggs/Release/v1.1.0

Release/v1.1.0

README.md

@@ -31,9 +31,33 @@ Usage:
 # [Module] photo/
 Generates Booky's Image URL. Module is named `photo` as to not override go's `image` package
 
-Usage: FormatImageURL(ID int, assetType string, filename string, extra ...string)
+Usage: 
++ FormatImageURL(ID int, assetType string, filename string, extra ...string)
  	- ID - ID of entity.
 	- assetType - Type of entity (e.g. 'offers' or 'brands')
 	- filename - Image filename
 	- extra - Accepts up to two optional parameters. Sets imageSize(default:`original`) and imageType(default:`photo`).
 	- Sample Output: "https://assets1.phonebooky.com/brands/photos/000/000/020/original/sample.jpg"
+
+# [Module] marshalling/
+Customized MarshalMap for dynamodb attributes. This will keep empty values _(empty strings, zeros, empty structs/objects)_ to persist them in dynamodb tables.
+
+Usage: 
++ CustomMarshalMap(in interface{})
+	- in - interface{} of value struct such as `{Renamed Brand 1 0xc0000874b0  inactive 0xc0000908c0}`
+
+	- Sample Output of type `map[string]*dynamodb.AttributeValue`:
+
+	```go
+	map[brand_name:{
+		S: "Renamed Brand 1"
+	} brand_status:{
+		S: "inactive"
+	} description:{
+		NULL: true
+	} offer:{
+		NULL: true
+	} offer_limit:{
+		N: "0"
+	}]
+	```

marshalling/custommarshal.go

@@ -0,0 +1,49 @@
+package marshalling
+
+import (
+	"reflect"
+
+	"github.com/aws/aws-sdk-go/service/dynamodb"
+	"github.com/aws/aws-sdk-go/service/dynamodb/dynamodbattribute"
+)
+
+// CustomMarshalMap is a custom marshal func which marshals Go value to AttributeValues
+func CustomMarshalMap(in interface{}) (map[string]*dynamodb.AttributeValue, error) {
+	av := dynamodbattribute.NewEncoder()
+	av.NullEmptyString = false // keep empty strings
+
+	// convert interface{} to map[string]*dynamodb.AttributeValue
+	aav, err := av.Encode(in)
+	if err != nil || av == nil || aav.M == nil {
+		return map[string]*dynamodb.AttributeValue{}, err
+	}
+
+	// loop over map[string]*dynamodb.AttributeValue
+	for key, elem := range aav.M {
+		// convert elem to Go value from *dynamodb.AttributeValue
+		var i interface{}
+		_ = dynamodbattribute.Unmarshal(elem, &i)
+
+		// change go value to reflect.Value for null checking
+		r := reflect.ValueOf(i)
+		if emptyValue(r) {
+			delete(aav.M, key)
+
+			// convert back to *dynamodb.AttributeValue
+			t := true
+			aav.M[key] = &dynamodb.AttributeValue{NULL: &t}
+		}
+	}
+
+	return aav.M, nil
+}
+
+func emptyValue(v reflect.Value) bool {
+	switch v.Kind() {
+	case reflect.Array, reflect.Map, reflect.Slice, reflect.String:
+		return v.Len() == 0
+	case reflect.Interface, reflect.Ptr:
+		return v.IsNil()
+	}
+	return false
+}

marshalling/custommarshal_test.go

@@ -0,0 +1,38 @@
+package marshalling
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+type Offer struct {
+	Title string `json:"title,omitempty"`
+}
+
+type Brand struct {
+	Name        string  `json:"brand_name,omitempty"`
+	Description *string `json:"description,omitempty"`
+	Kind        string  `json:"kind,omitempty"`
+	Status      string  `json:"brand_status,omitempty"`
+	Limit       *int    `json:"offer_limit,omitempty"`
+	Offer       *Offer  `json:"offer"`
+}
+
+func TestCustomMarshalMap(t *testing.T) {
+	description := ""
+	zero := 0
+	brand := Brand{
+		Name:        "Renamed Brand 1",
+		Status:      "inactive",
+		Description: &description,
+		Limit:       &zero,
+		Offer:       &Offer{},
+	}
+
+	res, err := CustomMarshalMap(brand)
+	assert.Equal(t, true, *res["description"].NULL)
+	assert.Equal(t, "0", *res["offer_limit"].N)
+	assert.Equal(t, true, *res["offer"].NULL)
+	assert.Nil(t, err)
+}

marshalling/go.mod

@@ -0,0 +1,8 @@
+module scrambledeggs/booky-go-common/marshalling
+
+go 1.12
+
+require (
+	github.com/aws/aws-sdk-go v1.25.4
+	github.com/stretchr/testify v1.4.0
+)

marshalling/go.sum

@@ -0,0 +1,14 @@
+github.com/aws/aws-sdk-go v1.25.4 h1:exwxtR517g6OKm2rtAD5EANtjbzmnjEAco189zy/Uhc=
+github.com/aws/aws-sdk-go v1.25.4/go.mod h1:KmX6BPdI08NWTb3/sm4ZGu5ShLoqVDhKgpiN924inxo=
+github.com/davecgh/go-spew v1.1.0 h1:ZDRjVQ15GmhC3fiQ8ni8+OwkZQO4DARzQgrnXU1Liz8=
+github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/jmespath/go-jmespath v0.0.0-20180206201540-c2b33e8439af h1:pmfjZENx5imkbgOkpRUYLnmbU7UEFbjtDA2hxJ1ichM=
+github.com/jmespath/go-jmespath v0.0.0-20180206201540-c2b33e8439af/go.mod h1:Nht3zPeWKUH0NzdCt2Blrr5ys8VGpn0CEB0cQHVjt7k=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+github.com/stretchr/testify v1.4.0 h1:2E4SXV/wtOkTonXsotYi4li6zVWxYlZuYNCXe9XRJyk=
+github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v2 v2.2.2 h1:ZCJp+EgiOT7lHqUV2J862kp8Qj64Jo6az82+3Td9dZw=
+gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=