Golang json.Marshal函數代碼示例

// get an id of an existing file, for _id access
func idOfFile(mf *MongoFiles, filename string) string {
	session, _ := mf.SessionProvider.GetSession()
	gfs := session.DB(mf.StorageOptions.DB).GridFS(mf.StorageOptions.GridFSPrefix)
	gFile, _ := gfs.Open(filename)
	bytes, _ := json.Marshal(gFile.Id())
	return fmt.Sprintf("ObjectId(%v)", string(bytes))
}

// ExportDocument writes a line to output with the CSV representation of a document.
func (csvExporter *CSVExportOutput) ExportDocument(document bson.D) error {
	rowOut := make([]string, 0, len(csvExporter.Fields))
	extendedDoc, err := bsonutil.ConvertBSONValueToJSON(document)
	if err != nil {
		return err
	}

	for _, fieldName := range csvExporter.Fields {
		fieldVal := extractFieldByName(fieldName, extendedDoc)
		if fieldVal == nil {
			rowOut = append(rowOut, "")
		} else if reflect.TypeOf(fieldVal) == reflect.TypeOf(bson.M{}) ||
			reflect.TypeOf(fieldVal) == reflect.TypeOf(bson.D{}) ||
			reflect.TypeOf(fieldVal) == marshalDType ||
			reflect.TypeOf(fieldVal) == reflect.TypeOf([]interface{}{}) {
			buf, err := json.Marshal(fieldVal)
			if err != nil {
				rowOut = append(rowOut, "")
			} else {
				rowOut = append(rowOut, string(buf))
			}
		} else {
			rowOut = append(rowOut, fmt.Sprintf("%v", fieldVal))
		}
	}
	csvExporter.csvWriter.Write(rowOut)
	csvExporter.NumExported++
	return csvExporter.csvWriter.Error()
}

//ExportDocument converts the given document to extended json, and writes it
//to the output.
func (jsonExporter *JSONExportOutput) ExportDocument(document bson.M) error {
	if jsonExporter.ArrayOutput {
		if jsonExporter.NumExported >= 1 {
			jsonExporter.Out.Write([]byte(","))
		}
		extendedDoc, err := bsonutil.ConvertBSONValueToJSON(document)
		if err != nil {
			return err
		}
		jsonOut, err := json.Marshal(extendedDoc)
		if err != nil {
			return fmt.Errorf("Error converting BSON to extended JSON: %v", err)
		}
		jsonExporter.Out.Write(jsonOut)
	} else {
		extendedDoc, err := bsonutil.ConvertBSONValueToJSON(document)
		if err != nil {
			return err
		}
		err = jsonExporter.Encoder.Encode(extendedDoc)
		if err != nil {
			return err
		}
	}
	jsonExporter.NumExported++
	return nil
}

func main() {
	runtime.GOMAXPROCS(runtime.NumCPU())
	flag.Parse()
	logger := log.New(os.Stderr, "ERROR: ", log.Ldate|log.Ltime|log.Lshortfile)

	pcap, err := pcap.OpenOffline(*pcapFile)
	if err != nil {
		fmt.Fprintln(os.Stderr, "error opening pcap file:", err)
		os.Exit(1)
	}
	h := mongocaputils.NewPacketHandler(pcap)
	m := mongocaputils.NewMongoOpStream(*packetBufSize)

	ch := make(chan struct{})
	go func() {
		defer close(ch)
		for op := range m.Ops {
			// TODO: add other op types
			if opQuery, ok := op.Op.(*mongoproto.OpQuery); ok {
				fbOp := map[string]interface{}{}
				fbOp["ns"] = opQuery.FullCollectionName
				fbOp["ntoskip"] = opQuery.NumberToSkip
				fbOp["ntoreturn"] = opQuery.NumberToReturn
				fbOp["ts"] = json.Date(op.Seen.Unix())
				query, err := rawBSONToJSON(opQuery.Query)
				if err != nil {
					logger.Println(err)
					if !*continueOnError {
						os.Exit(1)
					}
				}
				if strings.HasSuffix(opQuery.FullCollectionName, ".$cmd") {
					fbOp["op"] = "command"
					fbOp["command"] = query
				} else {
					fbOp["op"] = "query"
					fbOp["query"] = query
				}
				fbOpStr, err := json.Marshal(fbOp)
				if err != nil {
					logger.Println(err)
					if !*continueOnError {
						os.Exit(1)
					}
				}
				fmt.Println(string(fbOpStr))
			}
		}
	}()

	if err := h.Handle(m, -1); err != nil {
		fmt.Fprintln(os.Stderr, "pcap_converter: error handling packet stream:", err)
	}
	<-ch
}

func (op *QueryOp) getOpBodyString() (string, error) {
	queryAsJSON, err := ConvertBSONValueToJSON(op.Query)
	if err != nil {
		return "", fmt.Errorf("ConvertBSONValueToJSON err: %#v - %v", op, err)
	}
	asJSON, err := json.Marshal(queryAsJSON)
	if err != nil {
		return "", fmt.Errorf("json marshal err: %#v - %v", op, err)
	}
	return string(asJSON), nil
}

func dumpDoc(doc *bson.M, out io.Writer) error {
	extendedDoc, err := bsonutil.ConvertBSONValueToJSON(doc)
	if err != nil {
		return fmt.Errorf("Error converting BSON to extended JSON: %v", err)
	}
	jsonBytes, err := json.Marshal(extendedDoc)
	if err != nil {
		return fmt.Errorf("Error converting doc to JSON: %v", err)
	}
	_, err = out.Write(jsonBytes)
	return err
}

// MarshalJSON makes the MarshalD type usable by
// the encoding/json package.
func (md MarshalD) MarshalJSON() ([]byte, error) {
	var buff bytes.Buffer
	buff.WriteString("{")
	for i, item := range md {
		key, err := json.Marshal(item.Name)
		if err != nil {
			return nil, fmt.Errorf("cannot marshal key %v: %v", item.Name, err)
		}
		val, err := json.Marshal(item.Value)
		if err != nil {
			return nil, fmt.Errorf("cannot marshal value %v: %v", item.Value, err)
		}
		buff.Write(key)
		buff.WriteString(":")
		buff.Write(val)
		if i != len(md)-1 {
			buff.WriteString(",")
		}
	}
	buff.WriteString("}")
	return buff.Bytes(), nil
}

func (op *OpQuery) String() string {
	var query interface{}
	if err := bson.Unmarshal(op.Query, &query); err != nil {
		return "(error unmarshalling)"
	}
	queryAsJSON, err := bsonutil.ConvertBSONValueToJSON(query)
	if err != nil {
		return fmt.Sprintf("ConvertBSONValueToJSON err: %#v - %v", op, err)
	}
	asJSON, err := json.Marshal(queryAsJSON)
	if err != nil {
		return fmt.Sprintf("json marshal err: %#v - %v", op, err)
	}
	return fmt.Sprintf("OpQuery %v %v", op.FullCollectionName, string(asJSON))
}

func formatJSON(doc *bson.Raw, pretty bool) ([]byte, error) {
	decodedDoc := bson.D{}
	err := bson.Unmarshal(doc.Data, &decodedDoc)
	if err != nil {
		return nil, err
	}

	extendedDoc, err := bsonutil.ConvertBSONValueToJSON(decodedDoc)
	if err != nil {
		return nil, fmt.Errorf("error converting BSON to extended JSON: %v", err)
	}
	jsonBytes, err := json.Marshal(extendedDoc)
	if pretty {
		var jsonFormatted bytes.Buffer
		json.Indent(&jsonFormatted, jsonBytes, "", "\t")
		jsonBytes = jsonFormatted.Bytes()
	}
	if err != nil {
		return nil, fmt.Errorf("error converting doc to JSON: %v", err)
	}
	return jsonBytes, nil
}

func printJSON(doc *bson.Raw, out io.Writer, pretty bool) error {
	decodedDoc := bson.D{}
	err := bson.Unmarshal(doc.Data, &decodedDoc)
	if err != nil {
		return err
	}

	extendedDoc, err := bsonutil.ConvertBSONValueToJSON(decodedDoc)
	if err != nil {
		return fmt.Errorf("error converting BSON to extended JSON: %v", err)
	}
	jsonBytes, err := json.Marshal(extendedDoc)
	if pretty {
		var jsonFormatted bytes.Buffer
		json.Indent(&jsonFormatted, jsonBytes, "", "\t")
		jsonBytes = jsonFormatted.Bytes()
	}
	if err != nil {
		return fmt.Errorf("error converting doc to JSON: %v", err)
	}
	_, err = out.Write(jsonBytes)
	return err
}

// ExportDocument converts the given document to extended JSON, and writes it
// to the output.
func (jsonExporter *JSONExportOutput) ExportDocument(document bson.M) error {
	if jsonExporter.ArrayOutput || jsonExporter.PrettyOutput {
		if jsonExporter.NumExported >= 1 {
			if jsonExporter.ArrayOutput {
				jsonExporter.Out.Write([]byte(","))
			}
			if jsonExporter.PrettyOutput {
				jsonExporter.Out.Write([]byte("\n"))
			}
		}
		extendedDoc, err := bsonutil.ConvertBSONValueToJSON(document)
		if err != nil {
			return err
		}
		jsonOut, err := json.Marshal(extendedDoc)
		if err != nil {
			return fmt.Errorf("error converting BSON to extended JSON: %v", err)
		}
		if jsonExporter.PrettyOutput {
			var jsonFormatted bytes.Buffer
			json.Indent(&jsonFormatted, jsonOut, "", "\t")
			jsonOut = jsonFormatted.Bytes()
		}
		jsonExporter.Out.Write(jsonOut)
	} else {
		extendedDoc, err := bsonutil.ConvertBSONValueToJSON(document)
		if err != nil {
			return err
		}
		err = jsonExporter.Encoder.Encode(extendedDoc)
		if err != nil {
			return err
		}
	}
	jsonExporter.NumExported++
	return nil
}

//.........這裏部分代碼省略.........

					Reset(func() {
					})

				})

			})

			Convey("for an entire database", func() {
				md.ToolOptions.Namespace.Collection = ""
				err = md.Init()
				So(err, ShouldBeNil)

				Convey("that exists. The dumped directory should contain the necessary bson files", func() {
					md.OutputOptions.Out = "dump"
					err = md.Dump()
					So(err, ShouldBeNil)
					path, err := os.Getwd()
					So(err, ShouldBeNil)

					dumpDir := util.ToUniversalPath(filepath.Join(path, "dump"))
					dumpDBDir := util.ToUniversalPath(filepath.Join(dumpDir, testDB))
					So(fileDirExists(dumpDir), ShouldBeTrue)
					So(fileDirExists(dumpDBDir), ShouldBeTrue)

					countColls, err := countNonIndexBSONFiles(dumpDBDir)
					So(err, ShouldBeNil)
					So(countColls, ShouldEqual, len(testCollectionNames))

					Reset(func() {
						So(os.RemoveAll(dumpDir), ShouldBeNil)
					})

				})

				Convey("that does not exist. The dumped directory shouldn't be created", func() {
					md.OutputOptions.Out = "dump"
					md.ToolOptions.Namespace.DB = "nottestdb"
					err = md.Dump()
					So(err, ShouldBeNil)

					path, err := os.Getwd()
					So(err, ShouldBeNil)

					dumpDir := util.ToUniversalPath(filepath.Join(path, "dump"))
					dumpDBDir := util.ToUniversalPath(filepath.Join(dumpDir, "nottestdb"))

					So(fileDirExists(dumpDir), ShouldBeFalse)
					So(fileDirExists(dumpDBDir), ShouldBeFalse)
				})

			})
		})

		Convey("testing that using MongoDump WITH a query dumps a subset of documents in a database and/or collection", func() {
			session, err := getBareSession()
			So(err, ShouldBeNil)
			md := simpleMongoDumpInstance()

			// expect 10 documents per collection
			bsonQuery := bson.M{"age": bson.M{"$lt": 10}}
			jsonQuery, err := bsonutil.ConvertBSONValueToJSON(bsonQuery)
			So(err, ShouldBeNil)
			jsonQueryBytes, err := json.Marshal(jsonQuery)
			So(err, ShouldBeNil)

			Convey("using --query for all the collections in the database", func() {
				md.InputOptions.Query = string(jsonQueryBytes)
				md.ToolOptions.Namespace.DB = testDB
				md.OutputOptions.Out = "dump"
				dumpDir := testQuery(md, session)

				Reset(func() {
					So(session.DB(testRestoreDB).DropDatabase(), ShouldBeNil)
					So(os.RemoveAll(dumpDir), ShouldBeNil)
				})

			})

			Convey("using --queryFile for all the collections in the database", func() {
				ioutil.WriteFile("example.json", jsonQueryBytes, 0777)
				md.InputOptions.QueryFile = "example.json"
				md.ToolOptions.Namespace.DB = testDB
				md.OutputOptions.Out = "dump"
				dumpDir := testQuery(md, session)

				Reset(func() {
					So(session.DB(testRestoreDB).DropDatabase(), ShouldBeNil)
					So(os.RemoveAll(dumpDir), ShouldBeNil)
					So(os.Remove("example.json"), ShouldBeNil)
				})

			})
		})

		Reset(func() {
			So(tearDownMongoDumpTestData(), ShouldBeNil)
		})
	})
}

// dumpMetadata gets the metadata for a collection and writes it
// in readable JSON format.
func (dump *MongoDump) dumpMetadata(intent *intents.Intent) error {
	var err error

	nsID := fmt.Sprintf("%v.%v", intent.DB, intent.C)
	meta := Metadata{
		// We have to initialize Indexes to an empty slice, not nil, so that an empty
		// array is marshalled into json instead of null. That is, {indexes:[]} is okay
		// but {indexes:null} will cause assertions in our legacy C++ mongotools
		Indexes: []interface{}{},
	}

	// The collection options were already gathered while building the list of intents.
	// We convert them to JSON so that they can be written to the metadata json file as text.
	if intent.Options != nil {
		if meta.Options, err = bsonutil.ConvertBSONValueToJSON(*intent.Options); err != nil {
			return fmt.Errorf("error converting collection options to JSON: %v", err)
		}
	} else {
		meta.Options = nil
	}

	// Second, we read the collection's index information by either calling
	// listIndexes (pre-2.7 systems) or querying system.indexes.
	// We keep a running list of all the indexes
	// for the current collection as we iterate over the cursor, and include
	// that list as the "indexes" field of the metadata document.
	log.Logvf(log.DebugHigh, "\treading indexes for `%v`", nsID)

	session, err := dump.sessionProvider.GetSession()
	if err != nil {
		return err
	}
	defer session.Close()

	// get the indexes
	indexesIter, err := db.GetIndexes(session.DB(intent.DB).C(intent.C))
	if err != nil {
		return err
	}
	if indexesIter == nil {
		log.Logvf(log.Always, "the collection %v appears to have been dropped after the dump started", intent.Namespace())
		return nil
	}

	indexOpts := &bson.D{}
	for indexesIter.Next(indexOpts) {
		convertedIndex, err := bsonutil.ConvertBSONValueToJSON(*indexOpts)
		if err != nil {
			return fmt.Errorf("error converting index (%#v): %v", convertedIndex, err)
		}
		meta.Indexes = append(meta.Indexes, convertedIndex)
	}

	if err := indexesIter.Err(); err != nil {
		return fmt.Errorf("error getting indexes for collection `%v`: %v", nsID, err)
	}

	// Finally, we send the results to the writer as JSON bytes
	jsonBytes, err := json.Marshal(meta)
	if err != nil {
		return fmt.Errorf("error marshalling metadata json for collection `%v`: %v", nsID, err)
	}

	err = intent.MetadataFile.Open()
	if err != nil {
		return err
	}
	defer intent.MetadataFile.Close()
	// make a buffered writer for nicer disk i/o
	w := bufio.NewWriter(intent.MetadataFile)
	_, err = w.Write(jsonBytes)
	if err != nil {
		return fmt.Errorf("error writing metadata for collection `%v` to disk: %v", nsID, err)
	}
	err = w.Flush()
	if err != nil {
		return fmt.Errorf("error writing metadata for collection `%v` to disk: %v", nsID, err)
	}
	return nil
}