68 lines
1.1 KiB
Go
68 lines
1.1 KiB
Go
package exporter
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import (
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"io"
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"encoding/json"
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"github.com/google/cayley/graph"
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)
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type Exporter struct {
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wr io.Writer
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qstore graph.QuadStore
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err error
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count int32
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}
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func NewExporter(writer io.Writer, qstore graph.QuadStore) *Exporter {
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return &Exporter{wr: writer, qstore: qstore}
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}
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// number of records
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func (exp *Exporter) Count() int32 {
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return exp.count
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}
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func (exp *Exporter) ExportJson() {
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var jstr []byte
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exp.Write("[")
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it := exp.qstore.QuadsAllIterator()
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for graph.Next(it) {
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exp.count++
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if exp.count > 1 {
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exp.Write(",")
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}
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jstr, exp.err = json.Marshal(exp.qstore.Quad(it.Result()))
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if exp.err != nil {
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return
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}
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exp.Write(string(jstr[:]))
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}
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exp.Write("]\n")
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}
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//print out the string quoted, escaped
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func (exp *Exporter) WriteEscString(str string) {
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var esc []byte
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if exp.err != nil {
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return
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}
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esc, exp.err = json.Marshal(str)
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if exp.err != nil {
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return
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}
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_, exp.err = exp.wr.Write(esc)
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}
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func (exp *Exporter) Write(str string) {
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if exp.err != nil {
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return
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}
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_, exp.err = exp.wr.Write([]byte(str))
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}
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func (exp *Exporter) Err() error {
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return exp.err
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}
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