3 types of operation.
const (
TypeQuery operationType = "query"
TypeMutation operationType = "mutation"
TypeSubscription operationType = "subscription"
)
func StringFromChan(c <-chan string) string
StringFromChan builds a string from a channel, assuming the channel has been closed.
type Argument struct {
Name string
Value argumentValue
}
func ArgumentAny(name string, value interface{}) (Argument, error)
func ArgumentBool(name string, value bool) Argument
func ArgumentBoolSlice(name string, values ...bool) Argument
func ArgumentCustomType(name string, values ...Argument) Argument
ArgumentCustomType returns a custom GraphQL type's argument representation, which could be a recursive structure.
func ArgumentCustomTypeSlice(name string, values ...[]Argument) Argument
func ArgumentCustomTypeSliceElem(values ...Argument) []Argument
func ArgumentInt(name string, value int) Argument
func ArgumentIntSlice(name string, values ...int) Argument
func ArgumentString(name string, value string) Argument
func ArgumentStringSlice(name string, values ...string) Argument
ArgumentTypeNotSupportedErr is returned when user tries to pass an unsupported type to ArgumentAny.
type ArgumentTypeNotSupportedErr struct {
Value interface{}
}
func (e ArgumentTypeNotSupportedErr) Error() string
CyclicFieldErr is returned when any field contains a loop which goes back to itself.
type CyclicFieldErr struct {
Field Field
}
func (e CyclicFieldErr) Error() string
Field is a recursive data struct which represents a GraphQL query field.
type Field struct {
Name string
Alias string
Arguments []Argument
Fields []*Field
E error
}
func Fields(args ...string) []*Field
Fields takes a list of strings and make them a slice of *Field. This is useful when you want fields with no sub fields. For example:
query { courses { id, key } }
can be written as:
Query{
Type: "query",
Fields: []*Field{
{
Name: "courses",
Fields: Fields("id", "key"),
},
},
}
func MakeField(name string) *Field
MakeField constructs a Field of given name and return the pointer to this Field.
func NewField(name string, options ...FieldOptionInterface) *Field
NewField uses functional options to construct a new Field and returns the pointer to it. On error, the pointer is nil. To know more about this design pattern, see https://dave.cheney.net/2014/10/17/functional-options-for-friendly-apis
func (f *Field) AddArguments(argument ...Argument) *Field
func (f *Field) SetAlias(alias string) *Field
SetAlias sets the alias of a Field and return the pointer to this Field.
func (f *Field) SetArguments(arguments ...Argument) *Field
SetArguments sets the arguments of a Field and return the pointer to this Field.
func (f *Field) SetFields(fs ...*Field) *Field
SetFields sets the sub fields of a Field and return the pointer to this Field.
func (f *Field) StringChan() (<-chan string, error)
StringChan returns read only string token channel or an error. It checks if there is a circle.
FieldContainerOption implements FieldOptionInterface and QueryOptionInterface, which means, it can be used as the functional option for both NewQuery() and NewField(). FieldContainerOption is a function which takes in a fieldContainer and config it. Both Query and Field are fieldContainer.
type FieldContainerOption func(fc fieldContainer) error
func OfField(name string, options ...FieldOptionInterface) FieldContainerOption
OfField returns a FieldContainerOption and has the same parameter signature of NewField(name string, options ...FieldOptionInterface) (*Field, error)
FieldOption implements FieldOptionInterface
type FieldOption func(field *Field) error
func OfAlias(alias string) FieldOption
func OfArguments(arguments ...Argument) FieldOption
OfArguments returns a FieldOption which sets the arguments of the targeting field.
func OfFields(name ...string) FieldOption
OfFields returns a FieldOption which sets a list of sub fields of given names of the targeting field. All the sub fields only have one level which is their names. That is, no sub fields have sub fields.
FieldOptionInterface implements functional options for NewField().
type FieldOptionInterface interface {
// contains filtered or unexported methods
}
InvalidNameErr is returned when an invalid name is used. In GraphQL, operation, alias, field and argument all have names. A valid name matches ^[_A-Za-z][_0-9A-Za-z]*$ exactly.
type InvalidNameErr struct {
Type nameType
Name string
}
func (e InvalidNameErr) Error() string
InvalidOperationTypeErr is returned when the operation is not one of query, mutation and subscription.
type InvalidOperationTypeErr struct {
Type operationType
}
func (e InvalidOperationTypeErr) Error() string
NilFieldErr is returned when any field is nil. Of course the author could choose to ignore nil fields. But, author chose a stricter construct.
type NilFieldErr struct{}
func (e NilFieldErr) Error() string
Query represents a GraphQL query. Though all fields (Go struct field, not GraphQL field) of this struct is public, the author recommends you to use functions in public.go.
type Query struct {
Type operationType // The operation type is either query, mutation, or subscription.
Name string // The operation name is a meaningful and explicit name for your operation.
Fields []*Field
E error
}
func MakeQuery(Type operationType) *Query
MakeQuery constructs a Query of the given type and returns a pointer of it.
func NewQuery(Type operationType, options ...QueryOptionInterface) *Query
NewQuery uses functional options to construct a new Query and returns the pointer to it. On error, the pointer is nil. Type is required. Other options such as operation name and alias are optional.
func (q *Query) AddFields(fields ...*Field) *Query
AddFields adds to the Fields field of this Query.
func (q *Query) GetField(name string) *Field
GetField return the field identified by the name. Nil if not exist.
func (q *Query) JSON() (string, error)
JSON returns a json string with "query" field.
func (q *Query) SetFields(fields ...*Field) *Query
SetFields sets the Fields field of this Query. If q.Fields already contains data, they will be replaced.
func (q *Query) SetName(name string) *Query
SetName sets the Name field of this Query.
func (q *Query) StringChan() (<-chan string, error)
StringChan returns a string channel and an error. When error is not nil, the channel is nil. When error is nil, the channel is guaranteed to be closed. Warning: One should never receive from a nil channel for eternity awaits by a nil channel.
QueryOption implements QueryOptionInterface
type QueryOption func(query *Query) error
func OfName(name string) QueryOption
OfName returns a QueryOption which validates and sets the operation name of a query.
QueryOptionInterface implements functional options for NewQuery().
type QueryOptionInterface interface {
// contains filtered or unexported methods
}