311 lines
7.8 KiB
Go
311 lines
7.8 KiB
Go
package policy
|
|
|
|
import (
|
|
"errors"
|
|
"fmt"
|
|
"strconv"
|
|
"strings"
|
|
|
|
"github.com/antlr/antlr4/runtime/Go/antlr"
|
|
"github.com/nspcc-dev/neofs-sdk-go/netmap"
|
|
"github.com/nspcc-dev/neofs-sdk-go/policy/parser"
|
|
)
|
|
|
|
var (
|
|
// ErrInvalidNumber is returned when a value of SELECT is 0.
|
|
ErrInvalidNumber = errors.New("policy: expected positive integer")
|
|
// ErrUnknownClause is returned when a statement(clause) in a query is unknown.
|
|
ErrUnknownClause = errors.New("policy: unknown clause")
|
|
// ErrUnknownOp is returned when an operation in a query is unknown.
|
|
ErrUnknownOp = errors.New("policy: unknown operation")
|
|
// ErrUnknownFilter is returned when a value of FROM in a query is unknown.
|
|
ErrUnknownFilter = errors.New("policy: filter not found")
|
|
// ErrUnknownSelector is returned when a value of IN is unknown.
|
|
ErrUnknownSelector = errors.New("policy: selector not found")
|
|
// ErrSyntaxError is returned for errors found by ANTLR parser.
|
|
ErrSyntaxError = errors.New("policy: syntax error")
|
|
)
|
|
|
|
type policyVisitor struct {
|
|
errors []error
|
|
parser.BaseQueryVisitor
|
|
antlr.DefaultErrorListener
|
|
}
|
|
|
|
// Parse parses s into a placement policy.
|
|
func Parse(s string) (*netmap.PlacementPolicy, error) {
|
|
return parse(s)
|
|
}
|
|
|
|
func newPolicyVisitor() *policyVisitor {
|
|
return &policyVisitor{}
|
|
}
|
|
|
|
func parse(s string) (*netmap.PlacementPolicy, error) {
|
|
input := antlr.NewInputStream(s)
|
|
lexer := parser.NewQueryLexer(input)
|
|
stream := antlr.NewCommonTokenStream(lexer, 0)
|
|
|
|
p := parser.NewQuery(stream)
|
|
p.BuildParseTrees = true
|
|
|
|
v := newPolicyVisitor()
|
|
p.RemoveErrorListeners()
|
|
p.AddErrorListener(v)
|
|
pl := p.Policy().Accept(v)
|
|
|
|
if len(v.errors) != 0 {
|
|
return nil, v.errors[0]
|
|
}
|
|
if err := validatePolicy(pl.(*netmap.PlacementPolicy)); err != nil {
|
|
return nil, err
|
|
}
|
|
return pl.(*netmap.PlacementPolicy), nil
|
|
}
|
|
|
|
func (p *policyVisitor) SyntaxError(recognizer antlr.Recognizer, offendingSymbol interface{}, line, column int, msg string, e antlr.RecognitionException) {
|
|
p.reportError(fmt.Errorf("%w: line %d:%d %s", ErrSyntaxError, line, column, msg))
|
|
}
|
|
|
|
func (p *policyVisitor) reportError(err error) interface{} {
|
|
p.errors = append(p.errors, err)
|
|
return nil
|
|
}
|
|
|
|
// VisitPolicy implements parser.QueryVisitor interface.
|
|
func (p *policyVisitor) VisitPolicy(ctx *parser.PolicyContext) interface{} {
|
|
if len(p.errors) != 0 {
|
|
return nil
|
|
}
|
|
|
|
pl := new(netmap.PlacementPolicy)
|
|
|
|
repStmts := ctx.AllRepStmt()
|
|
rs := make([]*netmap.Replica, 0, len(repStmts))
|
|
for _, r := range repStmts {
|
|
res, ok := r.Accept(p).(*netmap.Replica)
|
|
if !ok {
|
|
return nil
|
|
}
|
|
|
|
rs = append(rs, res)
|
|
}
|
|
pl.SetReplicas(rs...)
|
|
|
|
if cbfStmt := ctx.CbfStmt(); cbfStmt != nil {
|
|
cbf, ok := cbfStmt.(*parser.CbfStmtContext).Accept(p).(uint32)
|
|
if !ok {
|
|
return nil
|
|
}
|
|
pl.SetContainerBackupFactor(cbf)
|
|
}
|
|
|
|
selStmts := ctx.AllSelectStmt()
|
|
ss := make([]*netmap.Selector, 0, len(selStmts))
|
|
for _, s := range selStmts {
|
|
res, ok := s.Accept(p).(*netmap.Selector)
|
|
if !ok {
|
|
return nil
|
|
}
|
|
|
|
ss = append(ss, res)
|
|
}
|
|
pl.SetSelectors(ss...)
|
|
|
|
filtStmts := ctx.AllFilterStmt()
|
|
fs := make([]*netmap.Filter, 0, len(filtStmts))
|
|
for _, f := range filtStmts {
|
|
fs = append(fs, f.Accept(p).(*netmap.Filter))
|
|
}
|
|
pl.SetFilters(fs...)
|
|
|
|
return pl
|
|
}
|
|
|
|
func (p *policyVisitor) VisitCbfStmt(ctx *parser.CbfStmtContext) interface{} {
|
|
cbf, err := strconv.ParseUint(ctx.GetBackupFactor().GetText(), 10, 32)
|
|
if err != nil {
|
|
return p.reportError(ErrInvalidNumber)
|
|
}
|
|
|
|
return uint32(cbf)
|
|
}
|
|
|
|
// VisitRepStmt implements parser.QueryVisitor interface.
|
|
func (p *policyVisitor) VisitRepStmt(ctx *parser.RepStmtContext) interface{} {
|
|
num, err := strconv.ParseUint(ctx.GetCount().GetText(), 10, 32)
|
|
if err != nil {
|
|
return p.reportError(ErrInvalidNumber)
|
|
}
|
|
|
|
rs := new(netmap.Replica)
|
|
rs.SetCount(uint32(num))
|
|
|
|
if sel := ctx.GetSelector(); sel != nil {
|
|
rs.SetSelector(sel.GetText())
|
|
}
|
|
|
|
return rs
|
|
}
|
|
|
|
// VisitSelectStmt implements parser.QueryVisitor interface.
|
|
func (p *policyVisitor) VisitSelectStmt(ctx *parser.SelectStmtContext) interface{} {
|
|
res, err := strconv.ParseUint(ctx.GetCount().GetText(), 10, 32)
|
|
if err != nil {
|
|
return p.reportError(ErrInvalidNumber)
|
|
}
|
|
|
|
s := new(netmap.Selector)
|
|
s.SetCount(uint32(res))
|
|
|
|
if clStmt := ctx.Clause(); clStmt != nil {
|
|
s.SetClause(clauseFromString(clStmt.GetText()))
|
|
}
|
|
|
|
if bStmt := ctx.GetBucket(); bStmt != nil {
|
|
s.SetAttribute(ctx.GetBucket().GetText())
|
|
}
|
|
|
|
s.SetFilter(ctx.GetFilter().GetText()) // either ident or wildcard
|
|
|
|
if ctx.AS() != nil {
|
|
s.SetName(ctx.GetName().GetText())
|
|
}
|
|
return s
|
|
}
|
|
|
|
// VisitFilterStmt implements parser.QueryVisitor interface.
|
|
func (p *policyVisitor) VisitFilterStmt(ctx *parser.FilterStmtContext) interface{} {
|
|
f := p.VisitFilterExpr(ctx.GetExpr().(*parser.FilterExprContext)).(*netmap.Filter)
|
|
f.SetName(ctx.GetName().GetText())
|
|
return f
|
|
}
|
|
|
|
func (p *policyVisitor) VisitFilterExpr(ctx *parser.FilterExprContext) interface{} {
|
|
if eCtx := ctx.Expr(); eCtx != nil {
|
|
return eCtx.Accept(p)
|
|
}
|
|
|
|
if inner := ctx.GetInner(); inner != nil {
|
|
return inner.Accept(p)
|
|
}
|
|
|
|
f := new(netmap.Filter)
|
|
op := operationFromString(ctx.GetOp().GetText())
|
|
f.SetOperation(op)
|
|
|
|
f1 := ctx.GetF1().Accept(p).(*netmap.Filter)
|
|
f2 := ctx.GetF2().Accept(p).(*netmap.Filter)
|
|
|
|
// Consider f1=(.. AND ..) AND f2. This can be merged because our AND operation
|
|
// is of arbitrary arity. ANTLR generates left-associative parse-tree by default.
|
|
if f1.Operation() == op {
|
|
f.SetInnerFilters(append(f1.InnerFilters(), f2)...)
|
|
return f
|
|
}
|
|
|
|
f.SetInnerFilters(f1, f2)
|
|
return f
|
|
}
|
|
|
|
// VisitFilterKey implements parser.QueryVisitor interface.
|
|
func (p *policyVisitor) VisitFilterKey(ctx *parser.FilterKeyContext) interface{} {
|
|
if id := ctx.Ident(); id != nil {
|
|
return id.GetText()
|
|
}
|
|
|
|
str := ctx.STRING().GetText()
|
|
return str[1 : len(str)-1]
|
|
}
|
|
|
|
func (p *policyVisitor) VisitFilterValue(ctx *parser.FilterValueContext) interface{} {
|
|
if id := ctx.Ident(); id != nil {
|
|
return id.GetText()
|
|
}
|
|
|
|
if num := ctx.Number(); num != nil {
|
|
return num.GetText()
|
|
}
|
|
|
|
str := ctx.STRING().GetText()
|
|
return str[1 : len(str)-1]
|
|
}
|
|
|
|
// VisitExpr implements parser.QueryVisitor interface.
|
|
func (p *policyVisitor) VisitExpr(ctx *parser.ExprContext) interface{} {
|
|
f := new(netmap.Filter)
|
|
if flt := ctx.GetFilter(); flt != nil {
|
|
f.SetName(flt.GetText())
|
|
return f
|
|
}
|
|
|
|
key := ctx.GetKey().Accept(p)
|
|
opStr := ctx.SIMPLE_OP().GetText()
|
|
value := ctx.GetValue().Accept(p)
|
|
|
|
f.SetKey(key.(string))
|
|
f.SetOperation(operationFromString(opStr))
|
|
f.SetValue(value.(string))
|
|
return f
|
|
}
|
|
|
|
// validatePolicy checks high-level constraints such as filter link in SELECT
|
|
// being actually defined in FILTER section.
|
|
func validatePolicy(p *netmap.PlacementPolicy) error {
|
|
seenFilters := map[string]bool{}
|
|
for _, f := range p.Filters() {
|
|
seenFilters[f.Name()] = true
|
|
}
|
|
|
|
seenSelectors := map[string]bool{}
|
|
for _, s := range p.Selectors() {
|
|
if flt := s.Filter(); flt != netmap.MainFilterName && !seenFilters[flt] {
|
|
return fmt.Errorf("%w: '%s'", ErrUnknownFilter, flt)
|
|
}
|
|
seenSelectors[s.Name()] = true
|
|
}
|
|
|
|
for _, r := range p.Replicas() {
|
|
if sel := r.Selector(); sel != "" && !seenSelectors[sel] {
|
|
return fmt.Errorf("%w: '%s'", ErrUnknownSelector, sel)
|
|
}
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
func clauseFromString(s string) netmap.Clause {
|
|
switch strings.ToUpper(s) {
|
|
case "SAME":
|
|
return netmap.ClauseSame
|
|
case "DISTINCT":
|
|
return netmap.ClauseDistinct
|
|
default:
|
|
// Such errors should be handled by ANTLR code thus this panic.
|
|
panic(fmt.Errorf("BUG: invalid clause: %s", s))
|
|
}
|
|
}
|
|
|
|
func operationFromString(op string) netmap.Operation {
|
|
switch strings.ToUpper(op) {
|
|
case "AND":
|
|
return netmap.OpAND
|
|
case "OR":
|
|
return netmap.OpOR
|
|
case "EQ":
|
|
return netmap.OpEQ
|
|
case "NE":
|
|
return netmap.OpNE
|
|
case "GE":
|
|
return netmap.OpGE
|
|
case "GT":
|
|
return netmap.OpGT
|
|
case "LE":
|
|
return netmap.OpLE
|
|
case "LT":
|
|
return netmap.OpLT
|
|
default:
|
|
// Such errors should be handled by ANTLR code thus this panic.
|
|
panic(fmt.Errorf("BUG: invalid operation: %s", op))
|
|
}
|
|
}
|