cayley/graph/sexp/session.go
2014-06-28 12:31:33 +09:30

121 lines
2.6 KiB
Go

// Copyright 2014 The Cayley Authors. All rights reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package sexp
// Defines a running session of the sexp query language.
import (
"errors"
"fmt"
"sort"
"github.com/google/cayley/graph"
)
type SexpSession struct {
ts graph.TripleStore
debug bool
}
func NewSexpSession(inputTripleStore graph.TripleStore) *SexpSession {
var s SexpSession
s.ts = inputTripleStore
return &s
}
func (s *SexpSession) ToggleDebug() {
s.debug = !s.debug
}
func (s *SexpSession) InputParses(input string) (graph.ParseResult, error) {
var parenDepth int
for i, x := range input {
if x == '(' {
parenDepth++
}
if x == ')' {
parenDepth--
if parenDepth < 0 {
min := 0
if (i - 10) > min {
min = i - 10
}
return graph.ParseFail, errors.New(fmt.Sprintf("Too many close parens at char %d: %s", i, input[min:i]))
}
}
}
if parenDepth > 0 {
return graph.ParseMore, nil
}
if len(ParseString(input)) > 0 {
return graph.Parsed, nil
}
return graph.ParseFail, errors.New("Invalid Syntax")
}
func (s *SexpSession) ExecInput(input string, out chan interface{}, limit int) {
it := BuildIteratorTreeForQuery(s.ts, input)
newIt, changed := it.Optimize()
if changed {
it = newIt
}
if s.debug {
fmt.Println(it.DebugString(0))
}
nResults := 0
for {
_, ok := it.Next()
if !ok {
break
}
tags := make(map[string]graph.TSVal)
it.TagResults(&tags)
out <- &tags
nResults++
if nResults > limit && limit != -1 {
break
}
for it.NextResult() == true {
tags := make(map[string]graph.TSVal)
it.TagResults(&tags)
out <- &tags
nResults++
if nResults > limit && limit != -1 {
break
}
}
}
close(out)
}
func (s *SexpSession) ToText(result interface{}) string {
out := fmt.Sprintln("****")
tags := result.(*map[string]graph.TSVal)
tagKeys := make([]string, len(*tags))
i := 0
for k, _ := range *tags {
tagKeys[i] = k
i++
}
sort.Strings(tagKeys)
for _, k := range tagKeys {
if k == "$_" {
continue
}
out += fmt.Sprintf("%s : %s\n", k, s.ts.GetNameFor((*tags)[k]))
}
return out
}