dynamodb/item.go
package dynamodb
import (
SDK "github.com/aws/aws-sdk-go/service/dynamodb"
"github.com/evalphobia/aws-sdk-go-wrapper/private/pointers"
)
// PutItem is wrapped struct for DynamoDB Item to put.
type PutItem struct {
data map[string]*SDK.AttributeValue
conditions map[string]*SDK.ExpectedAttributeValue
}
// NewPutItem returns initialized *PutItem.
func NewPutItem() *PutItem {
return &PutItem{
data: make(map[string]*SDK.AttributeValue),
conditions: make(map[string]*SDK.ExpectedAttributeValue),
}
}
// AddAttribute adds an attribute to the PutItem.
func (item *PutItem) AddAttribute(name string, value interface{}) {
item.data[name] = createAttributeValue(value)
}
// GetAttribute gets an attribute from PutItem.
func (item *PutItem) GetAttribute(name string) interface{} {
return item.data[name]
}
// AddConditionExist adds a EXIST condition.
func (item *PutItem) AddConditionExist(name string) {
item.addCondition(name, &SDK.ExpectedAttributeValue{
Exists: pointers.Bool(true),
})
}
// AddConditionNotExist adds a NOT EXIST condition.
func (item *PutItem) AddConditionNotExist(name string) {
item.addCondition(name, &SDK.ExpectedAttributeValue{
Exists: pointers.Bool(false),
})
}
// AddConditionEQ adds a EQUAL condition.
func (item *PutItem) AddConditionEQ(name string, value interface{}) {
cond := NewExpectedCondition(value, ComparisonOperatorEQ)
item.addCondition(name, cond)
}
// AddConditionNE adds a NOT EQUAL condition.
func (item *PutItem) AddConditionNE(name string, value interface{}) {
cond := NewExpectedCondition(value, ComparisonOperatorNE)
item.addCondition(name, cond)
}
// AddConditionGT adds a GREATER THAN condition.
func (item *PutItem) AddConditionGT(name string, value interface{}) {
cond := NewExpectedCondition(value, ComparisonOperatorGT)
item.addCondition(name, cond)
}
// AddConditionLT adds a LESS THAN condition.
func (item *PutItem) AddConditionLT(name string, value interface{}) {
cond := NewExpectedCondition(value, ComparisonOperatorLT)
item.addCondition(name, cond)
}
// AddConditionGE adds a GREATER THAN or EQUAL condition.
func (item *PutItem) AddConditionGE(name string, value interface{}) {
cond := NewExpectedCondition(value, ComparisonOperatorGE)
item.addCondition(name, cond)
}
// AddConditionLE adds a LESS THAN or EQUAL condition.
func (item *PutItem) AddConditionLE(name string, value interface{}) {
cond := NewExpectedCondition(value, ComparisonOperatorLE)
item.addCondition(name, cond)
}
// addCondition adds a condition.
func (item *PutItem) addCondition(name string, condition *SDK.ExpectedAttributeValue) {
item.conditions[name] = condition
}
// CountUp counts up the value.
func (item *PutItem) CountUp(name string, num int) {
// TODO: implement atomic counter
}
// CountDown counts down the value.
func (item *PutItem) CountDown(name string, num int) {
// TODO: implement atomic counter
}
// NewExpectedCondition returns *SDK.ExpectedAttributeValue with ComparisonOperator and value.
func NewExpectedCondition(value interface{}, operator string) *SDK.ExpectedAttributeValue {
v := createAttributeValue(value)
return &SDK.ExpectedAttributeValue{
Value: v,
ComparisonOperator: pointers.String(operator),
}
}