762 lines
13 KiB
Go
762 lines
13 KiB
Go
package qcode
|
|
|
|
import (
|
|
"errors"
|
|
"fmt"
|
|
"hash/maphash"
|
|
"sync"
|
|
"unsafe"
|
|
)
|
|
|
|
var (
|
|
errEOT = errors.New("end of tokens")
|
|
)
|
|
|
|
type parserType int32
|
|
|
|
const (
|
|
maxFields = 1200
|
|
maxArgs = 25
|
|
)
|
|
|
|
const (
|
|
parserError parserType = iota
|
|
parserEOF
|
|
opQuery
|
|
opMutate
|
|
opSub
|
|
NodeStr
|
|
NodeInt
|
|
NodeFloat
|
|
NodeBool
|
|
NodeObj
|
|
NodeList
|
|
NodeVar
|
|
)
|
|
|
|
type Operation struct {
|
|
Type parserType
|
|
Name string
|
|
Args []Arg
|
|
argsA [10]Arg
|
|
Fields []Field
|
|
fieldsA [10]Field
|
|
}
|
|
|
|
var zeroOperation = Operation{}
|
|
|
|
func (o *Operation) Reset() {
|
|
*o = zeroOperation
|
|
}
|
|
|
|
type Fragment struct {
|
|
Name string
|
|
On string
|
|
Fields []Field
|
|
fieldsA [10]Field
|
|
}
|
|
|
|
var zeroFragment = Fragment{}
|
|
|
|
func (f *Fragment) Reset() {
|
|
*f = zeroFragment
|
|
}
|
|
|
|
type Field struct {
|
|
ID int32
|
|
ParentID int32
|
|
Name string
|
|
Alias string
|
|
Args []Arg
|
|
argsA [5]Arg
|
|
Children []int32
|
|
childrenA [5]int32
|
|
Union bool
|
|
}
|
|
|
|
type Arg struct {
|
|
Name string
|
|
Val *Node
|
|
df bool
|
|
}
|
|
|
|
type Node struct {
|
|
Type parserType
|
|
Name string
|
|
Val string
|
|
Parent *Node
|
|
Children []*Node
|
|
exp *Exp
|
|
}
|
|
|
|
var zeroNode = Node{}
|
|
|
|
func (n *Node) Reset() {
|
|
*n = zeroNode
|
|
}
|
|
|
|
type Parser struct {
|
|
frags map[uint64]*Fragment
|
|
h maphash.Hash
|
|
input []byte // the string being scanned
|
|
pos int
|
|
items []item
|
|
err error
|
|
}
|
|
|
|
var nodePool = sync.Pool{
|
|
New: func() interface{} { return new(Node) },
|
|
}
|
|
|
|
var opPool = sync.Pool{
|
|
New: func() interface{} { return new(Operation) },
|
|
}
|
|
|
|
var fragPool = sync.Pool{
|
|
New: func() interface{} { return new(Fragment) },
|
|
}
|
|
|
|
var lexPool = sync.Pool{
|
|
New: func() interface{} { return new(lexer) },
|
|
}
|
|
|
|
func Parse(gql []byte) (*Operation, error) {
|
|
var err error
|
|
|
|
if len(gql) == 0 {
|
|
return nil, errors.New("blank query")
|
|
}
|
|
|
|
l := lexPool.Get().(*lexer)
|
|
l.Reset()
|
|
defer lexPool.Put(l)
|
|
|
|
if err = lex(l, gql); err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
p := &Parser{
|
|
input: l.input,
|
|
pos: -1,
|
|
items: l.items,
|
|
}
|
|
|
|
op := opPool.Get().(*Operation)
|
|
op.Reset()
|
|
op.Fields = op.fieldsA[:0]
|
|
|
|
s := -1
|
|
qf := false
|
|
|
|
for {
|
|
if p.peek(itemEOF) {
|
|
p.ignore()
|
|
break
|
|
}
|
|
|
|
if p.peek(itemFragment) {
|
|
p.ignore()
|
|
if f, err := p.parseFragment(); err != nil {
|
|
fragPool.Put(f)
|
|
return nil, err
|
|
}
|
|
|
|
} else {
|
|
if !qf && p.peek(itemQuery, itemMutation, itemSub, itemObjOpen) {
|
|
s = p.pos
|
|
qf = true
|
|
}
|
|
p.ignore()
|
|
}
|
|
}
|
|
|
|
p.reset(s)
|
|
if err := p.parseOp(op); err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
for _, v := range p.frags {
|
|
fragPool.Put(v)
|
|
}
|
|
|
|
return op, nil
|
|
}
|
|
|
|
func (p *Parser) parseFragment() (*Fragment, error) {
|
|
var err error
|
|
|
|
frag := fragPool.Get().(*Fragment)
|
|
frag.Reset()
|
|
frag.Fields = frag.fieldsA[:0]
|
|
|
|
if p.peek(itemName) {
|
|
frag.Name = p.val(p.next())
|
|
} else {
|
|
return frag, errors.New("fragment: missing name")
|
|
}
|
|
|
|
if p.peek(itemOn) {
|
|
p.ignore()
|
|
} else {
|
|
return frag, errors.New("fragment: missing 'on' keyword")
|
|
}
|
|
|
|
if p.peek(itemName) {
|
|
frag.On = p.vall(p.next())
|
|
} else {
|
|
return frag, errors.New("fragment: missing table name after 'on' keyword")
|
|
}
|
|
|
|
if p.peek(itemObjOpen) {
|
|
p.ignore()
|
|
} else {
|
|
return frag, fmt.Errorf("fragment: expecting a '{', got: %s", p.next())
|
|
}
|
|
|
|
frag.Fields, err = p.parseFields(frag.Fields)
|
|
if err != nil {
|
|
return frag, fmt.Errorf("fragment: %v", err)
|
|
}
|
|
|
|
if p.frags == nil {
|
|
p.frags = make(map[uint64]*Fragment)
|
|
}
|
|
|
|
_, _ = p.h.WriteString(frag.Name)
|
|
k := p.h.Sum64()
|
|
p.h.Reset()
|
|
|
|
p.frags[k] = frag
|
|
|
|
return frag, nil
|
|
}
|
|
|
|
func (p *Parser) parseOp(op *Operation) error {
|
|
var err error
|
|
var typeSet bool
|
|
|
|
if p.peek(itemQuery, itemMutation, itemSub) {
|
|
err = p.parseOpTypeAndArgs(op)
|
|
|
|
if err != nil {
|
|
return fmt.Errorf("%s: %v", op.Type, err)
|
|
}
|
|
typeSet = true
|
|
}
|
|
|
|
if p.peek(itemObjOpen) {
|
|
p.ignore()
|
|
if !typeSet {
|
|
op.Type = opQuery
|
|
}
|
|
|
|
for {
|
|
if p.peek(itemEOF, itemFragment) {
|
|
p.ignore()
|
|
break
|
|
}
|
|
|
|
op.Fields, err = p.parseFields(op.Fields)
|
|
if err != nil {
|
|
return fmt.Errorf("%s: %v", op.Type, err)
|
|
}
|
|
}
|
|
} else {
|
|
return fmt.Errorf("expecting a query, mutation or subscription, got: %s", p.next())
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
func (p *Parser) parseOpTypeAndArgs(op *Operation) error {
|
|
item := p.next()
|
|
|
|
switch item._type {
|
|
case itemQuery:
|
|
op.Type = opQuery
|
|
case itemMutation:
|
|
op.Type = opMutate
|
|
case itemSub:
|
|
op.Type = opSub
|
|
}
|
|
|
|
op.Args = op.argsA[:0]
|
|
|
|
var err error
|
|
|
|
if p.peek(itemName) {
|
|
op.Name = p.val(p.next())
|
|
}
|
|
|
|
if p.peek(itemArgsOpen) {
|
|
p.ignore()
|
|
|
|
op.Args, err = p.parseOpParams(op.Args)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
func ParseArgValue(argVal string) (*Node, error) {
|
|
l := lexPool.Get().(*lexer)
|
|
l.Reset()
|
|
|
|
if err := lex(l, []byte(argVal)); err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
p := &Parser{
|
|
input: l.input,
|
|
pos: -1,
|
|
items: l.items,
|
|
}
|
|
op, err := p.parseValue()
|
|
lexPool.Put(l)
|
|
|
|
return op, err
|
|
}
|
|
|
|
func (p *Parser) parseFields(fields []Field) ([]Field, error) {
|
|
var err error
|
|
st := NewStack()
|
|
|
|
if !p.peek(itemName, itemSpread) {
|
|
return nil, fmt.Errorf("unexpected token: %s", p.peekNext())
|
|
}
|
|
|
|
for {
|
|
if p.peek(itemEOF) {
|
|
p.ignore()
|
|
return nil, errors.New("invalid query")
|
|
}
|
|
|
|
if p.peek(itemObjClose) {
|
|
p.ignore()
|
|
|
|
if st.Len() != 0 {
|
|
st.Pop()
|
|
continue
|
|
} else {
|
|
break
|
|
}
|
|
}
|
|
|
|
if len(fields) >= maxFields {
|
|
return nil, fmt.Errorf("too many fields (max %d)", maxFields)
|
|
}
|
|
|
|
isFrag := false
|
|
|
|
if p.peek(itemSpread) {
|
|
p.ignore()
|
|
isFrag = true
|
|
}
|
|
|
|
if isFrag {
|
|
fields, err = p.parseFragmentFields(st, fields)
|
|
} else {
|
|
fields, err = p.parseNormalFields(st, fields)
|
|
}
|
|
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
}
|
|
|
|
return fields, nil
|
|
}
|
|
|
|
func (p *Parser) parseNormalFields(st *Stack, fields []Field) ([]Field, error) {
|
|
if !p.peek(itemName) {
|
|
return nil, fmt.Errorf("expecting an alias or field name, got: %s", p.next())
|
|
}
|
|
|
|
fields = append(fields, Field{ID: int32(len(fields))})
|
|
|
|
f := &fields[(len(fields) - 1)]
|
|
f.Args = f.argsA[:0]
|
|
f.Children = f.childrenA[:0]
|
|
|
|
// Parse the field
|
|
if err := p.parseField(f); err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
if st.Len() == 0 {
|
|
f.ParentID = -1
|
|
} else {
|
|
pid := st.Peek()
|
|
f.ParentID = pid
|
|
fields[pid].Children = append(fields[pid].Children, f.ID)
|
|
}
|
|
|
|
// The first opening curley brackets after this
|
|
// comes the columns or child fields
|
|
if p.peek(itemObjOpen) {
|
|
p.ignore()
|
|
st.Push(f.ID)
|
|
}
|
|
|
|
return fields, nil
|
|
}
|
|
|
|
func (p *Parser) parseFragmentFields(st *Stack, fields []Field) ([]Field, error) {
|
|
var err error
|
|
pid := st.Peek()
|
|
|
|
if p.peek(itemOn) {
|
|
p.ignore()
|
|
fields[pid].Union = true
|
|
|
|
if fields, err = p.parseNormalFields(st, fields); err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
// If parent is a union selector than copy over args from the parent
|
|
// to the first child which is the root selector for each union type.
|
|
for i := pid + 1; i < int32(len(fields)); i++ {
|
|
f := &fields[i]
|
|
if f.ParentID == pid {
|
|
f.Args = fields[pid].Args
|
|
}
|
|
}
|
|
|
|
} else {
|
|
if !p.peek(itemName) {
|
|
return nil, fmt.Errorf("expecting a fragment name, got: %s", p.next())
|
|
}
|
|
|
|
name := p.val(p.next())
|
|
_, _ = p.h.WriteString(name)
|
|
id := p.h.Sum64()
|
|
p.h.Reset()
|
|
|
|
fr, ok := p.frags[id]
|
|
if !ok {
|
|
return nil, fmt.Errorf("no fragment named '%s' defined", name)
|
|
}
|
|
ff := fr.Fields
|
|
|
|
n := int32(len(fields))
|
|
fields = append(fields, ff...)
|
|
|
|
for i := 0; i < len(ff); i++ {
|
|
k := (n + int32(i))
|
|
f := &fields[k]
|
|
f.ID = int32(k)
|
|
|
|
// If this is the top-level point the parent to the parent of the
|
|
// previous field.
|
|
if f.ParentID == -1 {
|
|
f.ParentID = pid
|
|
if f.ParentID != -1 {
|
|
fields[pid].Children = append(fields[pid].Children, f.ID)
|
|
}
|
|
// Update all the other parents id's by our new place in this new array
|
|
} else {
|
|
f.ParentID += n
|
|
}
|
|
|
|
// Copy over children since fields append is not a deep copy
|
|
f.Children = make([]int32, len(f.Children))
|
|
copy(f.Children, ff[i].Children)
|
|
|
|
// Copy over args since args append is not a deep copy
|
|
f.Args = make([]Arg, len(f.Args))
|
|
copy(f.Args, ff[i].Args)
|
|
|
|
// Update all the children which is needed.
|
|
for j := range f.Children {
|
|
f.Children[j] += n
|
|
}
|
|
}
|
|
}
|
|
|
|
return fields, nil
|
|
}
|
|
|
|
func (p *Parser) parseField(f *Field) error {
|
|
var err error
|
|
v := p.next()
|
|
|
|
if p.peek(itemColon) {
|
|
p.ignore()
|
|
|
|
if p.peek(itemName) {
|
|
f.Alias = p.val(v)
|
|
f.Name = p.vall(p.next())
|
|
} else {
|
|
return errors.New("expecting an aliased field name")
|
|
}
|
|
} else {
|
|
f.Name = p.vall(v)
|
|
}
|
|
|
|
if p.peek(itemArgsOpen) {
|
|
p.ignore()
|
|
if f.Args, err = p.parseArgs(f.Args); err != nil {
|
|
return err
|
|
}
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
func (p *Parser) parseOpParams(args []Arg) ([]Arg, error) {
|
|
for {
|
|
if len(args) >= maxArgs {
|
|
return nil, fmt.Errorf("too many args (max %d)", maxArgs)
|
|
}
|
|
|
|
if p.peek(itemEOF, itemArgsClose) {
|
|
p.ignore()
|
|
break
|
|
}
|
|
p.next()
|
|
}
|
|
|
|
return args, nil
|
|
}
|
|
|
|
func (p *Parser) parseArgs(args []Arg) ([]Arg, error) {
|
|
var err error
|
|
|
|
for {
|
|
if len(args) >= maxArgs {
|
|
return nil, fmt.Errorf("too many args (max %d)", maxArgs)
|
|
}
|
|
|
|
if p.peek(itemEOF, itemArgsClose) {
|
|
p.ignore()
|
|
break
|
|
}
|
|
|
|
if !p.peek(itemName) {
|
|
return nil, errors.New("expecting an argument name")
|
|
}
|
|
args = append(args, Arg{Name: p.val(p.next())})
|
|
arg := &args[(len(args) - 1)]
|
|
|
|
if !p.peek(itemColon) {
|
|
return nil, errors.New("missing ':' after argument name")
|
|
}
|
|
p.ignore()
|
|
|
|
arg.Val, err = p.parseValue()
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
}
|
|
return args, nil
|
|
}
|
|
|
|
func (p *Parser) parseList() (*Node, error) {
|
|
nodes := []*Node{}
|
|
|
|
parent := nodePool.Get().(*Node)
|
|
parent.Reset()
|
|
|
|
var ty parserType
|
|
for {
|
|
if p.peek(itemListClose) {
|
|
p.ignore()
|
|
break
|
|
}
|
|
node, err := p.parseValue()
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
if ty == 0 {
|
|
ty = node.Type
|
|
} else if ty != node.Type {
|
|
return nil, errors.New("All values in a list must be of the same type")
|
|
}
|
|
node.Parent = parent
|
|
nodes = append(nodes, node)
|
|
}
|
|
if len(nodes) == 0 {
|
|
return nil, errors.New("List cannot be empty")
|
|
}
|
|
|
|
parent.Type = NodeList
|
|
parent.Children = nodes
|
|
|
|
return parent, nil
|
|
}
|
|
|
|
func (p *Parser) parseObj() (*Node, error) {
|
|
nodes := []*Node{}
|
|
|
|
parent := nodePool.Get().(*Node)
|
|
parent.Reset()
|
|
|
|
for {
|
|
if p.peek(itemEOF, itemObjClose) {
|
|
p.ignore()
|
|
break
|
|
}
|
|
|
|
if !p.peek(itemName) {
|
|
return nil, errors.New("expecting an argument name")
|
|
}
|
|
nodeName := p.val(p.next())
|
|
|
|
if !p.peek(itemColon) {
|
|
return nil, errors.New("missing ':' after Field argument name")
|
|
}
|
|
p.ignore()
|
|
|
|
node, err := p.parseValue()
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
node.Name = nodeName
|
|
node.Parent = parent
|
|
nodes = append(nodes, node)
|
|
}
|
|
|
|
parent.Type = NodeObj
|
|
parent.Children = nodes
|
|
|
|
return parent, nil
|
|
}
|
|
|
|
func (p *Parser) parseValue() (*Node, error) {
|
|
if p.peek(itemListOpen) {
|
|
p.ignore()
|
|
return p.parseList()
|
|
}
|
|
|
|
if p.peek(itemObjOpen) {
|
|
p.ignore()
|
|
return p.parseObj()
|
|
}
|
|
|
|
item := p.next()
|
|
node := nodePool.Get().(*Node)
|
|
node.Reset()
|
|
|
|
switch item._type {
|
|
case itemIntVal:
|
|
node.Type = NodeInt
|
|
case itemFloatVal:
|
|
node.Type = NodeFloat
|
|
case itemStringVal:
|
|
node.Type = NodeStr
|
|
case itemBoolVal:
|
|
node.Type = NodeBool
|
|
case itemName:
|
|
node.Type = NodeStr
|
|
case itemVariable:
|
|
node.Type = NodeVar
|
|
default:
|
|
return nil, fmt.Errorf("expecting a number, string, object, list or variable as an argument value (not %s)", p.val(p.next()))
|
|
}
|
|
node.Val = p.val(item)
|
|
|
|
return node, nil
|
|
}
|
|
|
|
func (p *Parser) val(v item) string {
|
|
return b2s(p.input[v.pos:v.end])
|
|
}
|
|
|
|
func (p *Parser) vall(v item) string {
|
|
lowercase(p.input, v.pos, v.end)
|
|
return b2s(p.input[v.pos:v.end])
|
|
}
|
|
|
|
func (p *Parser) peek(types ...itemType) bool {
|
|
n := p.pos + 1
|
|
l := len(types)
|
|
// if p.items[n]._type == itemEOF {
|
|
// return false
|
|
// }
|
|
|
|
if n >= len(p.items) {
|
|
return types[0] == itemEOF
|
|
}
|
|
|
|
if l == 1 {
|
|
return p.items[n]._type == types[0]
|
|
}
|
|
|
|
for i := 0; i < l; i++ {
|
|
if p.items[n]._type == types[i] {
|
|
return true
|
|
}
|
|
}
|
|
return false
|
|
}
|
|
|
|
func (p *Parser) next() item {
|
|
n := p.pos + 1
|
|
if n >= len(p.items) {
|
|
p.err = errEOT
|
|
return item{_type: itemEOF}
|
|
}
|
|
p.pos = n
|
|
return p.items[p.pos]
|
|
}
|
|
|
|
func (p *Parser) ignore() {
|
|
n := p.pos + 1
|
|
if n >= len(p.items) {
|
|
p.err = errEOT
|
|
return
|
|
}
|
|
p.pos = n
|
|
}
|
|
|
|
func (p *Parser) peekNext() string {
|
|
item := p.items[p.pos+1]
|
|
return b2s(p.input[item.pos:item.end])
|
|
}
|
|
|
|
func (p *Parser) reset(to int) {
|
|
p.pos = to
|
|
}
|
|
|
|
func b2s(b []byte) string {
|
|
return *(*string)(unsafe.Pointer(&b))
|
|
}
|
|
|
|
func (t parserType) String() string {
|
|
var v string
|
|
|
|
switch t {
|
|
case parserEOF:
|
|
v = "EOF"
|
|
case parserError:
|
|
v = "error"
|
|
case opQuery:
|
|
v = "query"
|
|
case opMutate:
|
|
v = "mutation"
|
|
case opSub:
|
|
v = "subscription"
|
|
case NodeStr:
|
|
v = "node-string"
|
|
case NodeInt:
|
|
v = "node-int"
|
|
case NodeFloat:
|
|
v = "node-float"
|
|
case NodeBool:
|
|
v = "node-bool"
|
|
case NodeVar:
|
|
v = "node-var"
|
|
case NodeObj:
|
|
v = "node-obj"
|
|
case NodeList:
|
|
v = "node-list"
|
|
}
|
|
return v
|
|
}
|
|
|
|
func FreeNode(n *Node) {
|
|
nodePool.Put(n)
|
|
}
|