mirror of
https://github.com/rocky-linux/peridot.git
synced 2024-11-05 14:31:22 +00:00
639 lines
26 KiB
Go
639 lines
26 KiB
Go
package expression
|
|
|
|
import (
|
|
"fmt"
|
|
"strings"
|
|
|
|
"github.com/aws/aws-sdk-go/service/dynamodb"
|
|
"github.com/aws/aws-sdk-go/service/dynamodb/dynamodbattribute"
|
|
)
|
|
|
|
// ValueBuilder represents an item attribute value operand and implements the
|
|
// OperandBuilder interface. Methods and functions in the package take
|
|
// ValueBuilder as an argument and establishes relationships between operands.
|
|
// ValueBuilder should only be initialized using the function Value().
|
|
//
|
|
// Example:
|
|
//
|
|
// // Create a ValueBuilder representing the string "aValue"
|
|
// valueBuilder := expression.Value("aValue")
|
|
type ValueBuilder struct {
|
|
value interface{}
|
|
}
|
|
|
|
// NameBuilder represents a name of a top level item attribute or a nested
|
|
// attribute. Since NameBuilder represents a DynamoDB Operand, it implements the
|
|
// OperandBuilder interface. Methods and functions in the package take
|
|
// NameBuilder as an argument and establishes relationships between operands.
|
|
// NameBuilder should only be initialized using the function Name().
|
|
//
|
|
// Example:
|
|
//
|
|
// // Create a NameBuilder representing the item attribute "aName"
|
|
// nameBuilder := expression.Name("aName")
|
|
type NameBuilder struct {
|
|
name string
|
|
}
|
|
|
|
// SizeBuilder represents the output of the function size ("someName"), which
|
|
// evaluates to the size of the item attribute defined by "someName". Since
|
|
// SizeBuilder represents an operand, SizeBuilder implements the OperandBuilder
|
|
// interface. Methods and functions in the package take SizeBuilder as an
|
|
// argument and establishes relationships between operands. SizeBuilder should
|
|
// only be initialized using the function Size().
|
|
//
|
|
// Example:
|
|
//
|
|
// // Create a SizeBuilder representing the size of the item attribute
|
|
// // "aName"
|
|
// sizeBuilder := expression.Name("aName").Size()
|
|
type SizeBuilder struct {
|
|
nameBuilder NameBuilder
|
|
}
|
|
|
|
// KeyBuilder represents either the partition key or the sort key, both of which
|
|
// are top level attributes to some item in DynamoDB. Since KeyBuilder
|
|
// represents an operand, KeyBuilder implements the OperandBuilder interface.
|
|
// Methods and functions in the package take KeyBuilder as an argument and
|
|
// establishes relationships between operands. However, KeyBuilder should only
|
|
// be used to describe Key Condition Expressions. KeyBuilder should only be
|
|
// initialized using the function Key().
|
|
//
|
|
// Example:
|
|
//
|
|
// // Create a KeyBuilder representing the item key "aKey"
|
|
// keyBuilder := expression.Key("aKey")
|
|
type KeyBuilder struct {
|
|
key string
|
|
}
|
|
|
|
// setValueMode specifies the type of SetValueBuilder. The default value is
|
|
// unsetValue so that an UnsetParameterError when BuildOperand() is called on an
|
|
// empty SetValueBuilder.
|
|
type setValueMode int
|
|
|
|
const (
|
|
unsetValue setValueMode = iota
|
|
plusValueMode
|
|
minusValueMode
|
|
listAppendValueMode
|
|
ifNotExistsValueMode
|
|
)
|
|
|
|
// SetValueBuilder represents the outcome of operator functions supported by the
|
|
// DynamoDB Set operation. The operator functions are the following:
|
|
// Plus() // Represents the "+" operator
|
|
// Minus() // Represents the "-" operator
|
|
// ListAppend()
|
|
// IfNotExists()
|
|
// For documentation on the above functions,
|
|
// see: http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Expressions.UpdateExpressions.html#Expressions.UpdateExpressions.SET
|
|
// Since SetValueBuilder represents an operand, it implements the OperandBuilder
|
|
// interface. SetValueBuilder structs are used as arguments to the Set()
|
|
// function. SetValueBuilders should only initialize a SetValueBuilder using the
|
|
// functions listed above.
|
|
type SetValueBuilder struct {
|
|
leftOperand OperandBuilder
|
|
rightOperand OperandBuilder
|
|
mode setValueMode
|
|
}
|
|
|
|
// Operand represents an item attribute name or value in DynamoDB. The
|
|
// relationship between Operands specified by various builders such as
|
|
// ConditionBuilders and UpdateBuilders for example is processed internally to
|
|
// write Condition Expressions and Update Expressions respectively.
|
|
type Operand struct {
|
|
exprNode exprNode
|
|
}
|
|
|
|
// OperandBuilder represents the idea of Operand which are building blocks to
|
|
// DynamoDB Expressions. Package methods and functions can establish
|
|
// relationships between operands, representing DynamoDB Expressions. The method
|
|
// BuildOperand() is called recursively when the Build() method on the type
|
|
// Builder is called. BuildOperand() should never be called externally.
|
|
// OperandBuilder and BuildOperand() are exported to allow package functions to
|
|
// take an interface as an argument.
|
|
type OperandBuilder interface {
|
|
BuildOperand() (Operand, error)
|
|
}
|
|
|
|
// Name creates a NameBuilder. The argument should represent the desired item
|
|
// attribute. It is possible to reference nested item attributes by using
|
|
// square brackets for lists and dots for maps. For documentation on specifying
|
|
// item attributes,
|
|
// see: http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Expressions.Attributes.html
|
|
//
|
|
// Example:
|
|
//
|
|
// // Specify a top-level attribute
|
|
// name := expression.Name("TopLevel")
|
|
// // Specify a nested attribute
|
|
// nested := expression.Name("Record[6].SongList")
|
|
// // Use Name() to create a condition expression
|
|
// condition := expression.Name("foo").Equal(expression.Name("bar"))
|
|
func Name(name string) NameBuilder {
|
|
return NameBuilder{
|
|
name: name,
|
|
}
|
|
}
|
|
|
|
// Value creates a ValueBuilder and sets its value to the argument. The value
|
|
// will be marshalled using the dynamodbattribute package, unless it is of
|
|
// type dynamodb.AttributeValue, where it will be used directly.
|
|
//
|
|
// Empty slices and maps will be converted to NULL dynamodb.AttributeValue
|
|
// values. If an empty value is required, pass a dynamodb.AttributeValue, e.g.:
|
|
// emptyList := (&dynamodb.AttributeValue{}).SetL([]*dynamodb.AttributeValue{})
|
|
//
|
|
// Example:
|
|
//
|
|
// // Use Value() to create a condition expression
|
|
// condition := expression.Name("foo").Equal(expression.Value(10))
|
|
// // Use Value() to set the value of a set expression.
|
|
// update := Set(expression.Name("greets"), expression.Value((&dynamodb.AttributeValue{}).SetS("hello")))
|
|
func Value(value interface{}) ValueBuilder {
|
|
return ValueBuilder{
|
|
value: value,
|
|
}
|
|
}
|
|
|
|
// Size creates a SizeBuilder representing the size of the item attribute
|
|
// specified by the argument NameBuilder. Size() is only valid for certain types
|
|
// of item attributes. For documentation,
|
|
// see: http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Expressions.OperatorsAndFunctions.html
|
|
// SizeBuilder is only a valid operand in Condition Expressions and Filter
|
|
// Expressions.
|
|
//
|
|
// Example:
|
|
//
|
|
// // Use Size() to create a condition expression
|
|
// condition := expression.Name("foo").Size().Equal(expression.Value(10))
|
|
//
|
|
// Expression Equivalent:
|
|
//
|
|
// expression.Name("aName").Size()
|
|
// "size (aName)"
|
|
func (nb NameBuilder) Size() SizeBuilder {
|
|
return SizeBuilder{
|
|
nameBuilder: nb,
|
|
}
|
|
}
|
|
|
|
// Size creates a SizeBuilder representing the size of the item attribute
|
|
// specified by the argument NameBuilder. Size() is only valid for certain types
|
|
// of item attributes. For documentation,
|
|
// see: http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Expressions.OperatorsAndFunctions.html
|
|
// SizeBuilder is only a valid operand in Condition Expressions and Filter
|
|
// Expressions.
|
|
//
|
|
// Example:
|
|
//
|
|
// // Use Size() to create a condition expression
|
|
// condition := expression.Size(expression.Name("foo")).Equal(expression.Value(10))
|
|
//
|
|
// Expression Equivalent:
|
|
//
|
|
// expression.Size(expression.Name("aName"))
|
|
// "size (aName)"
|
|
func Size(nameBuilder NameBuilder) SizeBuilder {
|
|
return nameBuilder.Size()
|
|
}
|
|
|
|
// Key creates a KeyBuilder. The argument should represent the desired partition
|
|
// key or sort key value. KeyBuilders should only be used to specify
|
|
// relationships for Key Condition Expressions. When referring to the partition
|
|
// key or sort key in any other Expression, use Name().
|
|
//
|
|
// Example:
|
|
//
|
|
// // Use Key() to create a key condition expression
|
|
// keyCondition := expression.Key("foo").Equal(expression.Value("bar"))
|
|
func Key(key string) KeyBuilder {
|
|
return KeyBuilder{
|
|
key: key,
|
|
}
|
|
}
|
|
|
|
// Plus creates a SetValueBuilder to be used in as an argument to Set(). The
|
|
// arguments can either be NameBuilders or ValueBuilders. Plus() only supports
|
|
// DynamoDB Number types, so the ValueBuilder must be a Number and the
|
|
// NameBuilder must specify an item attribute of type Number.
|
|
// More information: http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Expressions.UpdateExpressions.html#Expressions.UpdateExpressions.SET.IncrementAndDecrement
|
|
//
|
|
// Example:
|
|
//
|
|
// // Use Plus() to set the value of the item attribute "someName" to 5 + 10
|
|
// update, err := expression.Set(expression.Name("someName"), expression.Plus(expression.Value(5), expression.Value(10)))
|
|
//
|
|
// Expression Equivalent:
|
|
//
|
|
// expression.Plus(expression.Value(5), expression.Value(10))
|
|
// // let :five and :ten be ExpressionAttributeValues for the values 5 and
|
|
// // 10 respectively.
|
|
// ":five + :ten"
|
|
func Plus(leftOperand, rightOperand OperandBuilder) SetValueBuilder {
|
|
return SetValueBuilder{
|
|
leftOperand: leftOperand,
|
|
rightOperand: rightOperand,
|
|
mode: plusValueMode,
|
|
}
|
|
}
|
|
|
|
// Plus creates a SetValueBuilder to be used in as an argument to Set(). The
|
|
// arguments can either be NameBuilders or ValueBuilders. Plus() only supports
|
|
// DynamoDB Number types, so the ValueBuilder must be a Number and the
|
|
// NameBuilder must specify an item attribute of type Number.
|
|
// More information: http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Expressions.UpdateExpressions.html#Expressions.UpdateExpressions.SET.IncrementAndDecrement
|
|
//
|
|
// Example:
|
|
//
|
|
// // Use Plus() to set the value of the item attribute "someName" to the
|
|
// // numeric value of item attribute "aName" incremented by 10
|
|
// update, err := expression.Set(expression.Name("someName"), expression.Name("aName").Plus(expression.Value(10)))
|
|
//
|
|
// Expression Equivalent:
|
|
//
|
|
// expression.Name("aName").Plus(expression.Value(10))
|
|
// // let :ten be ExpressionAttributeValues representing the value 10
|
|
// "aName + :ten"
|
|
func (nb NameBuilder) Plus(rightOperand OperandBuilder) SetValueBuilder {
|
|
return Plus(nb, rightOperand)
|
|
}
|
|
|
|
// Plus creates a SetValueBuilder to be used in as an argument to Set(). The
|
|
// arguments can either be NameBuilders or ValueBuilders. Plus() only supports
|
|
// DynamoDB Number types, so the ValueBuilder must be a Number and the
|
|
// NameBuilder must specify an item attribute of type Number.
|
|
// More information: http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Expressions.UpdateExpressions.html#Expressions.UpdateExpressions.SET.IncrementAndDecrement
|
|
//
|
|
// Example:
|
|
//
|
|
// // Use Plus() to set the value of the item attribute "someName" to 5 + 10
|
|
// update, err := expression.Set(expression.Name("someName"), expression.Value(5).Plus(expression.Value(10)))
|
|
//
|
|
// Expression Equivalent:
|
|
//
|
|
// expression.Value(5).Plus(expression.Value(10))
|
|
// // let :five and :ten be ExpressionAttributeValues representing the value
|
|
// // 5 and 10 respectively
|
|
// ":five + :ten"
|
|
func (vb ValueBuilder) Plus(rightOperand OperandBuilder) SetValueBuilder {
|
|
return Plus(vb, rightOperand)
|
|
}
|
|
|
|
// Minus creates a SetValueBuilder to be used in as an argument to Set(). The
|
|
// arguments can either be NameBuilders or ValueBuilders. Minus() only supports
|
|
// DynamoDB Number types, so the ValueBuilder must be a Number and the
|
|
// NameBuilder must specify an item attribute of type Number.
|
|
// More information: http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Expressions.UpdateExpressions.html#Expressions.UpdateExpressions.SET.IncrementAndDecrement
|
|
//
|
|
// Example:
|
|
//
|
|
// // Use Minus() to set the value of item attribute "someName" to 5 - 10
|
|
// update, err := expression.Set(expression.Name("someName"), expression.Minus(expression.Value(5), expression.Value(10)))
|
|
//
|
|
// Expression Equivalent:
|
|
//
|
|
// expression.Minus(expression.Value(5), expression.Value(10))
|
|
// // let :five and :ten be ExpressionAttributeValues for the values 5 and
|
|
// // 10 respectively.
|
|
// ":five - :ten"
|
|
func Minus(leftOperand, rightOperand OperandBuilder) SetValueBuilder {
|
|
return SetValueBuilder{
|
|
leftOperand: leftOperand,
|
|
rightOperand: rightOperand,
|
|
mode: minusValueMode,
|
|
}
|
|
}
|
|
|
|
// Minus creates a SetValueBuilder to be used in as an argument to Set(). The
|
|
// arguments can either be NameBuilders or ValueBuilders. Minus() only supports
|
|
// DynamoDB Number types, so the ValueBuilder must be a Number and the
|
|
// NameBuilder must specify an item attribute of type Number.
|
|
// More information: http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Expressions.UpdateExpressions.html#Expressions.UpdateExpressions.SET.IncrementAndDecrement
|
|
//
|
|
// Example:
|
|
//
|
|
// // Use Minus() to set the value of item attribute "someName" to the
|
|
// // numeric value of "aName" decremented by 10
|
|
// update, err := expression.Set(expression.Name("someName"), expression.Name("aName").Minus(expression.Value(10)))
|
|
//
|
|
// Expression Equivalent:
|
|
//
|
|
// expression.Name("aName").Minus(expression.Value(10)))
|
|
// // let :ten be ExpressionAttributeValues represent the value 10
|
|
// "aName - :ten"
|
|
func (nb NameBuilder) Minus(rightOperand OperandBuilder) SetValueBuilder {
|
|
return Minus(nb, rightOperand)
|
|
}
|
|
|
|
// Minus creates a SetValueBuilder to be used in as an argument to Set(). The
|
|
// arguments can either be NameBuilders or ValueBuilders. Minus() only supports
|
|
// DynamoDB Number types, so the ValueBuilder must be a Number and the
|
|
// NameBuilder must specify an item attribute of type Number.
|
|
// More information: http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Expressions.UpdateExpressions.html#Expressions.UpdateExpressions.SET.IncrementAndDecrement
|
|
//
|
|
// Example:
|
|
//
|
|
// // Use Minus() to set the value of item attribute "someName" to 5 - 10
|
|
// update, err := expression.Set(expression.Name("someName"), expression.Value(5).Minus(expression.Value(10)))
|
|
//
|
|
// Expression Equivalent:
|
|
//
|
|
// expression.Value(5).Minus(expression.Value(10))
|
|
// // let :five and :ten be ExpressionAttributeValues for the values 5 and
|
|
// // 10 respectively.
|
|
// ":five - :ten"
|
|
func (vb ValueBuilder) Minus(rightOperand OperandBuilder) SetValueBuilder {
|
|
return Minus(vb, rightOperand)
|
|
}
|
|
|
|
// ListAppend creates a SetValueBuilder to be used in as an argument to Set().
|
|
// The arguments can either be NameBuilders or ValueBuilders. ListAppend() only
|
|
// supports DynamoDB List types, so the ValueBuilder must be a List and the
|
|
// NameBuilder must specify an item attribute of type List.
|
|
// More information: http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Expressions.UpdateExpressions.html#Expressions.UpdateExpressions.SET.UpdatingListElements
|
|
//
|
|
// Example:
|
|
//
|
|
// // Use ListAppend() to set item attribute "someName" to the item
|
|
// // attribute "nameOfList" with "some" and "list" appended to it
|
|
// update, err := expression.Set(expression.Name("someName"), expression.ListAppend(expression.Name("nameOfList"), expression.Value([]string{"some", "list"})))
|
|
//
|
|
// Expression Equivalent:
|
|
//
|
|
// expression.ListAppend(expression.Name("nameOfList"), expression.Value([]string{"some", "list"})
|
|
// // let :list be a ExpressionAttributeValue representing the list
|
|
// // containing "some" and "list".
|
|
// "list_append (nameOfList, :list)"
|
|
func ListAppend(leftOperand, rightOperand OperandBuilder) SetValueBuilder {
|
|
return SetValueBuilder{
|
|
leftOperand: leftOperand,
|
|
rightOperand: rightOperand,
|
|
mode: listAppendValueMode,
|
|
}
|
|
}
|
|
|
|
// ListAppend creates a SetValueBuilder to be used in as an argument to Set().
|
|
// The arguments can either be NameBuilders or ValueBuilders. ListAppend() only
|
|
// supports DynamoDB List types, so the ValueBuilder must be a List and the
|
|
// NameBuilder must specify an item attribute of type List.
|
|
// More information: http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Expressions.UpdateExpressions.html#Expressions.UpdateExpressions.SET.UpdatingListElements
|
|
//
|
|
// Example:
|
|
//
|
|
// // Use ListAppend() to set item attribute "someName" to the item
|
|
// // attribute "nameOfList" with "some" and "list" appended to it
|
|
// update, err := expression.Set(expression.Name("someName"), expression.Name("nameOfList").ListAppend(expression.Value([]string{"some", "list"})))
|
|
//
|
|
// Expression Equivalent:
|
|
//
|
|
// expression.Name("nameOfList").ListAppend(expression.Value([]string{"some", "list"})
|
|
// // let :list be a ExpressionAttributeValue representing the list
|
|
// // containing "some" and "list".
|
|
// "list_append (nameOfList, :list)"
|
|
func (nb NameBuilder) ListAppend(rightOperand OperandBuilder) SetValueBuilder {
|
|
return ListAppend(nb, rightOperand)
|
|
}
|
|
|
|
// ListAppend creates a SetValueBuilder to be used in as an argument to Set().
|
|
// The arguments can either be NameBuilders or ValueBuilders. ListAppend() only
|
|
// supports DynamoDB List types, so the ValueBuilder must be a List and the
|
|
// NameBuilder must specify an item attribute of type List.
|
|
// More information: http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Expressions.UpdateExpressions.html#Expressions.UpdateExpressions.SET.UpdatingListElements
|
|
//
|
|
// Example:
|
|
//
|
|
// // Use ListAppend() to set item attribute "someName" to a string list
|
|
// // equal to {"a", "list", "some", "list"}
|
|
// update, err := expression.Set(expression.Name("someName"), expression.Value([]string{"a", "list"}).ListAppend(expression.Value([]string{"some", "list"})))
|
|
//
|
|
// Expression Equivalent:
|
|
//
|
|
// expression.Name([]string{"a", "list"}).ListAppend(expression.Value([]string{"some", "list"})
|
|
// // let :list1 and :list2 be a ExpressionAttributeValue representing the
|
|
// // list {"a", "list"} and {"some", "list"} respectively
|
|
// "list_append (:list1, :list2)"
|
|
func (vb ValueBuilder) ListAppend(rightOperand OperandBuilder) SetValueBuilder {
|
|
return ListAppend(vb, rightOperand)
|
|
}
|
|
|
|
// IfNotExists creates a SetValueBuilder to be used in as an argument to Set().
|
|
// The first argument must be a NameBuilder representing the name where the new
|
|
// item attribute is created. The second argument can either be a NameBuilder or
|
|
// a ValueBuilder. In the case that it is a NameBuilder, the value of the item
|
|
// attribute at the name specified becomes the value of the new item attribute.
|
|
// More information: http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Expressions.UpdateExpressions.html#Expressions.UpdateExpressions.SET.PreventingAttributeOverwrites
|
|
//
|
|
// Example:
|
|
//
|
|
// // Use IfNotExists() to set item attribute "someName" to value 5 if
|
|
// // "someName" does not exist yet. (Prevents overwrite)
|
|
// update, err := expression.Set(expression.Name("someName"), expression.IfNotExists(expression.Name("someName"), expression.Value(5)))
|
|
//
|
|
// Expression Equivalent:
|
|
//
|
|
// expression.IfNotExists(expression.Name("someName"), expression.Value(5))
|
|
// // let :five be a ExpressionAttributeValue representing the value 5
|
|
// "if_not_exists (someName, :five)"
|
|
func IfNotExists(name NameBuilder, setValue OperandBuilder) SetValueBuilder {
|
|
return SetValueBuilder{
|
|
leftOperand: name,
|
|
rightOperand: setValue,
|
|
mode: ifNotExistsValueMode,
|
|
}
|
|
}
|
|
|
|
// IfNotExists creates a SetValueBuilder to be used in as an argument to Set().
|
|
// The first argument must be a NameBuilder representing the name where the new
|
|
// item attribute is created. The second argument can either be a NameBuilder or
|
|
// a ValueBuilder. In the case that it is a NameBuilder, the value of the item
|
|
// attribute at the name specified becomes the value of the new item attribute.
|
|
// More information: http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Expressions.UpdateExpressions.html#Expressions.UpdateExpressions.SET.PreventingAttributeOverwrites
|
|
//
|
|
// Example:
|
|
//
|
|
// // Use IfNotExists() to set item attribute "someName" to value 5 if
|
|
// // "someName" does not exist yet. (Prevents overwrite)
|
|
// update, err := expression.Set(expression.Name("someName"), expression.Name("someName").IfNotExists(expression.Value(5)))
|
|
//
|
|
// Expression Equivalent:
|
|
//
|
|
// expression.Name("someName").IfNotExists(expression.Value(5))
|
|
// // let :five be a ExpressionAttributeValue representing the value 5
|
|
// "if_not_exists (someName, :five)"
|
|
func (nb NameBuilder) IfNotExists(rightOperand OperandBuilder) SetValueBuilder {
|
|
return IfNotExists(nb, rightOperand)
|
|
}
|
|
|
|
// BuildOperand creates an Operand struct which are building blocks to DynamoDB
|
|
// Expressions. Package methods and functions can establish relationships
|
|
// between operands, representing DynamoDB Expressions. The method
|
|
// BuildOperand() is called recursively when the Build() method on the type
|
|
// Builder is called. BuildOperand() should never be called externally.
|
|
// BuildOperand() aliases all strings to avoid stepping over DynamoDB's reserved
|
|
// words.
|
|
// More information on reserved words at http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/ReservedWords.html
|
|
func (nb NameBuilder) BuildOperand() (Operand, error) {
|
|
if nb.name == "" {
|
|
return Operand{}, newUnsetParameterError("BuildOperand", "NameBuilder")
|
|
}
|
|
|
|
node := exprNode{
|
|
names: []string{},
|
|
}
|
|
|
|
nameSplit := strings.Split(nb.name, ".")
|
|
fmtNames := make([]string, 0, len(nameSplit))
|
|
|
|
for _, word := range nameSplit {
|
|
var substr string
|
|
if word == "" {
|
|
return Operand{}, newInvalidParameterError("BuildOperand", "NameBuilder")
|
|
}
|
|
|
|
if word[len(word)-1] == ']' {
|
|
for j, char := range word {
|
|
if char == '[' {
|
|
substr = word[j:]
|
|
word = word[:j]
|
|
break
|
|
}
|
|
}
|
|
}
|
|
|
|
if word == "" {
|
|
return Operand{}, newInvalidParameterError("BuildOperand", "NameBuilder")
|
|
}
|
|
|
|
// Create a string with special characters that can be substituted later: $p
|
|
node.names = append(node.names, word)
|
|
fmtNames = append(fmtNames, "$n"+substr)
|
|
}
|
|
node.fmtExpr = strings.Join(fmtNames, ".")
|
|
return Operand{
|
|
exprNode: node,
|
|
}, nil
|
|
}
|
|
|
|
// BuildOperand creates an Operand struct which are building blocks to DynamoDB
|
|
// Expressions. Package methods and functions can establish relationships
|
|
// between operands, representing DynamoDB Expressions. The method
|
|
// BuildOperand() is called recursively when the Build() method on the type
|
|
// Builder is called. BuildOperand() should never be called externally.
|
|
// BuildOperand() aliases all strings to avoid stepping over DynamoDB's reserved
|
|
// words.
|
|
// More information on reserved words at http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/ReservedWords.html
|
|
func (vb ValueBuilder) BuildOperand() (Operand, error) {
|
|
var (
|
|
expr *dynamodb.AttributeValue
|
|
err error
|
|
)
|
|
|
|
switch v := vb.value.(type) {
|
|
case *dynamodb.AttributeValue:
|
|
expr = v
|
|
case dynamodb.AttributeValue:
|
|
expr = &v
|
|
default:
|
|
expr, err = dynamodbattribute.Marshal(vb.value)
|
|
if err != nil {
|
|
return Operand{}, newInvalidParameterError("BuildOperand", "ValueBuilder")
|
|
}
|
|
}
|
|
|
|
// Create a string with special characters that can be substituted later: $v
|
|
operand := Operand{
|
|
exprNode: exprNode{
|
|
values: []dynamodb.AttributeValue{*expr},
|
|
fmtExpr: "$v",
|
|
},
|
|
}
|
|
return operand, nil
|
|
}
|
|
|
|
// BuildOperand creates an Operand struct which are building blocks to DynamoDB
|
|
// Expressions. Package methods and functions can establish relationships
|
|
// between operands, representing DynamoDB Expressions. The method
|
|
// BuildOperand() is called recursively when the Build() method on the type
|
|
// Builder is called. BuildOperand() should never be called externally.
|
|
// BuildOperand() aliases all strings to avoid stepping over DynamoDB's reserved
|
|
// words.
|
|
// More information on reserved words at http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/ReservedWords.html
|
|
func (sb SizeBuilder) BuildOperand() (Operand, error) {
|
|
operand, err := sb.nameBuilder.BuildOperand()
|
|
operand.exprNode.fmtExpr = "size (" + operand.exprNode.fmtExpr + ")"
|
|
|
|
return operand, err
|
|
}
|
|
|
|
// BuildOperand creates an Operand struct which are building blocks to DynamoDB
|
|
// Expressions. Package methods and functions can establish relationships
|
|
// between operands, representing DynamoDB Expressions. The method
|
|
// BuildOperand() is called recursively when the Build() method on the type
|
|
// Builder is called. BuildOperand() should never be called externally.
|
|
// BuildOperand() aliases all strings to avoid stepping over DynamoDB's reserved
|
|
// words.
|
|
// More information on reserved words at http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/ReservedWords.html
|
|
func (kb KeyBuilder) BuildOperand() (Operand, error) {
|
|
if kb.key == "" {
|
|
return Operand{}, newUnsetParameterError("BuildOperand", "KeyBuilder")
|
|
}
|
|
|
|
ret := Operand{
|
|
exprNode: exprNode{
|
|
names: []string{kb.key},
|
|
fmtExpr: "$n",
|
|
},
|
|
}
|
|
|
|
return ret, nil
|
|
}
|
|
|
|
// BuildOperand creates an Operand struct which are building blocks to DynamoDB
|
|
// Expressions. Package methods and functions can establish relationships
|
|
// between operands, representing DynamoDB Expressions. The method
|
|
// BuildOperand() is called recursively when the Build() method on the type
|
|
// Builder is called. BuildOperand() should never be called externally.
|
|
// BuildOperand() aliases all strings to avoid stepping over DynamoDB's reserved
|
|
// words.
|
|
// More information on reserved words at http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/ReservedWords.html
|
|
func (svb SetValueBuilder) BuildOperand() (Operand, error) {
|
|
if svb.mode == unsetValue {
|
|
return Operand{}, newUnsetParameterError("BuildOperand", "SetValueBuilder")
|
|
}
|
|
|
|
left, err := svb.leftOperand.BuildOperand()
|
|
if err != nil {
|
|
return Operand{}, err
|
|
}
|
|
leftNode := left.exprNode
|
|
|
|
right, err := svb.rightOperand.BuildOperand()
|
|
if err != nil {
|
|
return Operand{}, err
|
|
}
|
|
rightNode := right.exprNode
|
|
|
|
node := exprNode{
|
|
children: []exprNode{leftNode, rightNode},
|
|
}
|
|
|
|
switch svb.mode {
|
|
case plusValueMode:
|
|
node.fmtExpr = "$c + $c"
|
|
case minusValueMode:
|
|
node.fmtExpr = "$c - $c"
|
|
case listAppendValueMode:
|
|
node.fmtExpr = "list_append($c, $c)"
|
|
case ifNotExistsValueMode:
|
|
node.fmtExpr = "if_not_exists($c, $c)"
|
|
default:
|
|
return Operand{}, fmt.Errorf("build operand error: unsupported mode: %v", svb.mode)
|
|
}
|
|
|
|
return Operand{
|
|
exprNode: node,
|
|
}, nil
|
|
}
|