resolver

Documentation

Index

• func GetPrimValueFuncName(primKind proto.RGQLPrimitive_Kind) string
• func ResolveError(rctx *Context, err error)
• func ResolveObject(rctx *Context, table FieldTable)
• func ResolveSlice(ctx *Context, sliceLen int, resolveFunc func(ictx *Context, i int))
• func ResolveValue(rctx *Context, isFinal bool, getValue func() *Value)
• func ResolveValueSlice(ctx *Context, sliceLen int, indexResolver func(i int) *Value)
• type Context
  • func NewContext(ctx context.Context, qnode *qtree.QueryTreeNode, writer ValueWriter) *Context
  • func (c *Context) ArrayChild(index int) *Context
  • func (c *Context) FieldChild(qnode *qtree.QueryTreeNode) *Context
  • func (c *Context) GetQueryArgument(argName string) *varstore.VariableReference
  • func (c *Context) MarkFinal()
  • func (c *Context) Purge()
  • func (c *Context) SetError(err error)
  • func (c *Context) VirtualChild() *Context
  • func (c *Context) WriteValue(val *Value, isFinal bool)
• type FieldResolver
• type FieldTable
• type Observable
  • func NewObservable(val interface{}) *Observable
  • func (o *Observable) Get() interface{}
  • func (o *Observable) Set(val interface{})
  • func (o *Observable) Subscribe(ctx context.Context, write func(v interface{}))
• type Value
  • func BuildBoolValue(val bool) *Value
  • func BuildErrorValue(err error) *Value
  • func BuildFloatValue(val float64) *Value
  • func BuildIntValue(val int32) *Value
  • func BuildNullValue() *Value
  • func BuildStringValue(val string) *Value
• type ValueWriter

Functions

func GetPrimValueFuncName

func GetPrimValueFuncName(primKind proto.RGQLPrimitive_Kind) string

GetPrimValueFuncName maps the primitive type to a value builder. String -> BuildStringValue Int -> BuildIntValue Bool -> BuildBoolValue, etc... Returns "" if undefined.

func ResolveError

func ResolveError(rctx *Context, err error)

ResolveError applies an error to a resolver context. If err == nil|context.Canceled, calls SetFinal to mark the node as done. Otherwise, marks the resolver context with the error.

func ResolveObject

func ResolveObject(rctx *Context, table FieldTable)

ResolveObject watches the query node fields and executes field resolvers.

func ResolveSlice

func ResolveSlice(ctx *Context, sliceLen int, resolveFunc func(ictx *Context, i int))

ResolveSlice resolves a slice of values.

func ResolveValue

func ResolveValue(rctx *Context, isFinal bool, getValue func() *Value)

ResolveValue resolves a context with a value.

func ResolveValueSlice

func ResolveValueSlice(
	ctx *Context,
	sliceLen int,
	indexResolver func(i int) *Value,
)

ResolveValueSlice iterates over the slice Each function call returns a resolver.Value at index This value is emitted at the array index i.

Types

type Context

type Context struct {
	// Context is the cancellation context
	Context context.Context
	// ContextCancel is the cancellation context cancel func
	ContextCancel context.CancelFunc

	// QNode is the query tree node
	QNode *qtree.QueryTreeNode
	// PathParent is the next parent in the chain that has a path component.
	PathParent *Context
	// PathComponent is the path component.
	// This is sometimes nil (TODO: when?)
	PathComponent *proto.RGQLValue

	// PathMtx locks the path components.
	PathMtx sync.Mutex
	// IsFinal indicates the context is finalized
	IsFinal bool
	// ActiveChildren is the number of active resolver children.
	ActiveChildren int
	// contains filtered or unexported fields
}

Context implements the resolver context. This context tracks: - Current query tree node - Position in output (for result encoding) - If we are an element in an array or not

func NewContext

func NewContext(ctx context.Context, qnode *qtree.QueryTreeNode, writer ValueWriter) *Context

NewContext builds a new root context.

func (*Context) ArrayChild

func (c *Context) ArrayChild(index int) *Context

ArrayChild builds a child resolver context with an index in an array.

func (*Context) FieldChild

func (c *Context) FieldChild(qnode *qtree.QueryTreeNode) *Context

FieldChild builds a child resolver context for a field resolver.

func (*Context) GetQueryArgument

func (c *Context) GetQueryArgument(argName string) *varstore.VariableReference

GetQueryArgument returns a query argument by argument name.

func (*Context) MarkFinal

func (c *Context) MarkFinal()

MarkFinal marks the context as complete.

func (*Context) Purge

func (c *Context) Purge()

Purge cancels the context.

func (*Context) SetError

func (c *Context) SetError(err error)

SetError marks an error on the resolver node.

func (*Context) VirtualChild

func (c *Context) VirtualChild() *Context

VirtualChild builds a virtual child resolver context that can be canceled if/when a new value becomes available.

func (*Context) WriteValue

func (c *Context) WriteValue(val *Value, isFinal bool)

WriteValue writes the value at the position.

type FieldResolver

type FieldResolver func(rctx *Context)

FieldResolver resolves a field on an object.

type FieldTable

type FieldTable map[uint32]FieldResolver

FieldTable is a mapping between field ID and resolver.

type Observable

type Observable struct {
	// contains filtered or unexported fields
}

Observable contains a value that can be subscribed to. The zero value is valid, with an empty val. Untyped nil is considered an empty value.

func NewObservable

func NewObservable(val interface{}) *Observable

NewObservable builds a new observable with an initial value.

func (*Observable) Get

func (o *Observable) Get() interface{}

Get returns the current instantaneous value.

func (*Observable) Set

func (o *Observable) Set(val interface{})

Set sets the next value.

func (*Observable) Subscribe

func (o *Observable) Subscribe(ctx context.Context, write func(v interface{}))

Subscribe subscribes to the value.

type Value

type Value struct {
	Context *Context
	Value   *proto.RGQLPrimitive
	Error   error
}

Value is a primitive value emitted by a resolver.

func BuildBoolValue

func BuildBoolValue(val bool) *Value

BuildBoolValue returns a boolean primitive value.

func BuildErrorValue

func BuildErrorValue(err error) *Value

BuildErrorValue builds a resolver value with an error.

func BuildFloatValue

func BuildFloatValue(val float64) *Value

BuildFloatValue returns a float primitive value.

func BuildIntValue

func BuildIntValue(val int32) *Value

BuildIntValue returns a int primitive value.

func BuildNullValue

func BuildNullValue() *Value

BuildNullValue returns the null primitive value.

func BuildStringValue

func BuildStringValue(val string) *Value

BuildStringValue returns a string primitive value.

type ValueWriter

type ValueWriter interface {
	WriteValue(value *Value)
}

ValueWriter handles writing values for fields.