mirror of
https://github.com/superseriousbusiness/gotosocial.git
synced 2024-11-29 15:12:45 +00:00
9d0df426da
* feat: vendor minio client * feat: introduce storage package with s3 support * feat: serve s3 files directly this saves a lot of bandwith as the files are fetched from the object store directly * fix: use explicit local storage in tests * feat: integrate s3 storage with the main server * fix: add s3 config to cli tests * docs: explicitly set values in example config also adds license header to the storage package * fix: use better http status code on s3 redirect HTTP 302 Found is the best fit, as it signifies that the resource requested was found but not under its presumed URL 307/TemporaryRedirect would mean that this resource is usually located here, not in this case 303/SeeOther indicates that the redirection does not link to the requested resource but to another page * refactor: use context in storage driver interface
758 lines
21 KiB
Go
758 lines
21 KiB
Go
/*
|
|
* MinIO Go Library for Amazon S3 Compatible Cloud Storage
|
|
* (C) 2018-2020 MinIO, Inc.
|
|
*
|
|
* 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 minio
|
|
|
|
import (
|
|
"bytes"
|
|
"context"
|
|
"encoding/binary"
|
|
"encoding/xml"
|
|
"errors"
|
|
"fmt"
|
|
"hash"
|
|
"hash/crc32"
|
|
"io"
|
|
"net/http"
|
|
"net/url"
|
|
"strings"
|
|
|
|
"github.com/minio/minio-go/v7/pkg/encrypt"
|
|
"github.com/minio/minio-go/v7/pkg/s3utils"
|
|
)
|
|
|
|
// CSVFileHeaderInfo - is the parameter for whether to utilize headers.
|
|
type CSVFileHeaderInfo string
|
|
|
|
// Constants for file header info.
|
|
const (
|
|
CSVFileHeaderInfoNone CSVFileHeaderInfo = "NONE"
|
|
CSVFileHeaderInfoIgnore = "IGNORE"
|
|
CSVFileHeaderInfoUse = "USE"
|
|
)
|
|
|
|
// SelectCompressionType - is the parameter for what type of compression is
|
|
// present
|
|
type SelectCompressionType string
|
|
|
|
// Constants for compression types under select API.
|
|
const (
|
|
SelectCompressionNONE SelectCompressionType = "NONE"
|
|
SelectCompressionGZIP = "GZIP"
|
|
SelectCompressionBZIP = "BZIP2"
|
|
|
|
// Non-standard compression schemes, supported by MinIO hosts:
|
|
|
|
SelectCompressionZSTD = "ZSTD" // Zstandard compression.
|
|
SelectCompressionLZ4 = "LZ4" // LZ4 Stream
|
|
SelectCompressionS2 = "S2" // S2 Stream
|
|
SelectCompressionSNAPPY = "SNAPPY" // Snappy stream
|
|
)
|
|
|
|
// CSVQuoteFields - is the parameter for how CSV fields are quoted.
|
|
type CSVQuoteFields string
|
|
|
|
// Constants for csv quote styles.
|
|
const (
|
|
CSVQuoteFieldsAlways CSVQuoteFields = "Always"
|
|
CSVQuoteFieldsAsNeeded = "AsNeeded"
|
|
)
|
|
|
|
// QueryExpressionType - is of what syntax the expression is, this should only
|
|
// be SQL
|
|
type QueryExpressionType string
|
|
|
|
// Constants for expression type.
|
|
const (
|
|
QueryExpressionTypeSQL QueryExpressionType = "SQL"
|
|
)
|
|
|
|
// JSONType determines json input serialization type.
|
|
type JSONType string
|
|
|
|
// Constants for JSONTypes.
|
|
const (
|
|
JSONDocumentType JSONType = "DOCUMENT"
|
|
JSONLinesType = "LINES"
|
|
)
|
|
|
|
// ParquetInputOptions parquet input specific options
|
|
type ParquetInputOptions struct{}
|
|
|
|
// CSVInputOptions csv input specific options
|
|
type CSVInputOptions struct {
|
|
FileHeaderInfo CSVFileHeaderInfo
|
|
fileHeaderInfoSet bool
|
|
|
|
RecordDelimiter string
|
|
recordDelimiterSet bool
|
|
|
|
FieldDelimiter string
|
|
fieldDelimiterSet bool
|
|
|
|
QuoteCharacter string
|
|
quoteCharacterSet bool
|
|
|
|
QuoteEscapeCharacter string
|
|
quoteEscapeCharacterSet bool
|
|
|
|
Comments string
|
|
commentsSet bool
|
|
}
|
|
|
|
// SetFileHeaderInfo sets the file header info in the CSV input options
|
|
func (c *CSVInputOptions) SetFileHeaderInfo(val CSVFileHeaderInfo) {
|
|
c.FileHeaderInfo = val
|
|
c.fileHeaderInfoSet = true
|
|
}
|
|
|
|
// SetRecordDelimiter sets the record delimiter in the CSV input options
|
|
func (c *CSVInputOptions) SetRecordDelimiter(val string) {
|
|
c.RecordDelimiter = val
|
|
c.recordDelimiterSet = true
|
|
}
|
|
|
|
// SetFieldDelimiter sets the field delimiter in the CSV input options
|
|
func (c *CSVInputOptions) SetFieldDelimiter(val string) {
|
|
c.FieldDelimiter = val
|
|
c.fieldDelimiterSet = true
|
|
}
|
|
|
|
// SetQuoteCharacter sets the quote character in the CSV input options
|
|
func (c *CSVInputOptions) SetQuoteCharacter(val string) {
|
|
c.QuoteCharacter = val
|
|
c.quoteCharacterSet = true
|
|
}
|
|
|
|
// SetQuoteEscapeCharacter sets the quote escape character in the CSV input options
|
|
func (c *CSVInputOptions) SetQuoteEscapeCharacter(val string) {
|
|
c.QuoteEscapeCharacter = val
|
|
c.quoteEscapeCharacterSet = true
|
|
}
|
|
|
|
// SetComments sets the comments character in the CSV input options
|
|
func (c *CSVInputOptions) SetComments(val string) {
|
|
c.Comments = val
|
|
c.commentsSet = true
|
|
}
|
|
|
|
// MarshalXML - produces the xml representation of the CSV input options struct
|
|
func (c CSVInputOptions) MarshalXML(e *xml.Encoder, start xml.StartElement) error {
|
|
if err := e.EncodeToken(start); err != nil {
|
|
return err
|
|
}
|
|
if c.FileHeaderInfo != "" || c.fileHeaderInfoSet {
|
|
if err := e.EncodeElement(c.FileHeaderInfo, xml.StartElement{Name: xml.Name{Local: "FileHeaderInfo"}}); err != nil {
|
|
return err
|
|
}
|
|
}
|
|
|
|
if c.RecordDelimiter != "" || c.recordDelimiterSet {
|
|
if err := e.EncodeElement(c.RecordDelimiter, xml.StartElement{Name: xml.Name{Local: "RecordDelimiter"}}); err != nil {
|
|
return err
|
|
}
|
|
}
|
|
|
|
if c.FieldDelimiter != "" || c.fieldDelimiterSet {
|
|
if err := e.EncodeElement(c.FieldDelimiter, xml.StartElement{Name: xml.Name{Local: "FieldDelimiter"}}); err != nil {
|
|
return err
|
|
}
|
|
}
|
|
|
|
if c.QuoteCharacter != "" || c.quoteCharacterSet {
|
|
if err := e.EncodeElement(c.QuoteCharacter, xml.StartElement{Name: xml.Name{Local: "QuoteCharacter"}}); err != nil {
|
|
return err
|
|
}
|
|
}
|
|
|
|
if c.QuoteEscapeCharacter != "" || c.quoteEscapeCharacterSet {
|
|
if err := e.EncodeElement(c.QuoteEscapeCharacter, xml.StartElement{Name: xml.Name{Local: "QuoteEscapeCharacter"}}); err != nil {
|
|
return err
|
|
}
|
|
}
|
|
|
|
if c.Comments != "" || c.commentsSet {
|
|
if err := e.EncodeElement(c.Comments, xml.StartElement{Name: xml.Name{Local: "Comments"}}); err != nil {
|
|
return err
|
|
}
|
|
}
|
|
|
|
return e.EncodeToken(xml.EndElement{Name: start.Name})
|
|
}
|
|
|
|
// CSVOutputOptions csv output specific options
|
|
type CSVOutputOptions struct {
|
|
QuoteFields CSVQuoteFields
|
|
quoteFieldsSet bool
|
|
|
|
RecordDelimiter string
|
|
recordDelimiterSet bool
|
|
|
|
FieldDelimiter string
|
|
fieldDelimiterSet bool
|
|
|
|
QuoteCharacter string
|
|
quoteCharacterSet bool
|
|
|
|
QuoteEscapeCharacter string
|
|
quoteEscapeCharacterSet bool
|
|
}
|
|
|
|
// SetQuoteFields sets the quote field parameter in the CSV output options
|
|
func (c *CSVOutputOptions) SetQuoteFields(val CSVQuoteFields) {
|
|
c.QuoteFields = val
|
|
c.quoteFieldsSet = true
|
|
}
|
|
|
|
// SetRecordDelimiter sets the record delimiter character in the CSV output options
|
|
func (c *CSVOutputOptions) SetRecordDelimiter(val string) {
|
|
c.RecordDelimiter = val
|
|
c.recordDelimiterSet = true
|
|
}
|
|
|
|
// SetFieldDelimiter sets the field delimiter character in the CSV output options
|
|
func (c *CSVOutputOptions) SetFieldDelimiter(val string) {
|
|
c.FieldDelimiter = val
|
|
c.fieldDelimiterSet = true
|
|
}
|
|
|
|
// SetQuoteCharacter sets the quote character in the CSV output options
|
|
func (c *CSVOutputOptions) SetQuoteCharacter(val string) {
|
|
c.QuoteCharacter = val
|
|
c.quoteCharacterSet = true
|
|
}
|
|
|
|
// SetQuoteEscapeCharacter sets the quote escape character in the CSV output options
|
|
func (c *CSVOutputOptions) SetQuoteEscapeCharacter(val string) {
|
|
c.QuoteEscapeCharacter = val
|
|
c.quoteEscapeCharacterSet = true
|
|
}
|
|
|
|
// MarshalXML - produces the xml representation of the CSVOutputOptions struct
|
|
func (c CSVOutputOptions) MarshalXML(e *xml.Encoder, start xml.StartElement) error {
|
|
if err := e.EncodeToken(start); err != nil {
|
|
return err
|
|
}
|
|
|
|
if c.QuoteFields != "" || c.quoteFieldsSet {
|
|
if err := e.EncodeElement(c.QuoteFields, xml.StartElement{Name: xml.Name{Local: "QuoteFields"}}); err != nil {
|
|
return err
|
|
}
|
|
}
|
|
|
|
if c.RecordDelimiter != "" || c.recordDelimiterSet {
|
|
if err := e.EncodeElement(c.RecordDelimiter, xml.StartElement{Name: xml.Name{Local: "RecordDelimiter"}}); err != nil {
|
|
return err
|
|
}
|
|
}
|
|
|
|
if c.FieldDelimiter != "" || c.fieldDelimiterSet {
|
|
if err := e.EncodeElement(c.FieldDelimiter, xml.StartElement{Name: xml.Name{Local: "FieldDelimiter"}}); err != nil {
|
|
return err
|
|
}
|
|
}
|
|
|
|
if c.QuoteCharacter != "" || c.quoteCharacterSet {
|
|
if err := e.EncodeElement(c.QuoteCharacter, xml.StartElement{Name: xml.Name{Local: "QuoteCharacter"}}); err != nil {
|
|
return err
|
|
}
|
|
}
|
|
|
|
if c.QuoteEscapeCharacter != "" || c.quoteEscapeCharacterSet {
|
|
if err := e.EncodeElement(c.QuoteEscapeCharacter, xml.StartElement{Name: xml.Name{Local: "QuoteEscapeCharacter"}}); err != nil {
|
|
return err
|
|
}
|
|
}
|
|
|
|
return e.EncodeToken(xml.EndElement{Name: start.Name})
|
|
}
|
|
|
|
// JSONInputOptions json input specific options
|
|
type JSONInputOptions struct {
|
|
Type JSONType
|
|
typeSet bool
|
|
}
|
|
|
|
// SetType sets the JSON type in the JSON input options
|
|
func (j *JSONInputOptions) SetType(typ JSONType) {
|
|
j.Type = typ
|
|
j.typeSet = true
|
|
}
|
|
|
|
// MarshalXML - produces the xml representation of the JSONInputOptions struct
|
|
func (j JSONInputOptions) MarshalXML(e *xml.Encoder, start xml.StartElement) error {
|
|
if err := e.EncodeToken(start); err != nil {
|
|
return err
|
|
}
|
|
|
|
if j.Type != "" || j.typeSet {
|
|
if err := e.EncodeElement(j.Type, xml.StartElement{Name: xml.Name{Local: "Type"}}); err != nil {
|
|
return err
|
|
}
|
|
}
|
|
|
|
return e.EncodeToken(xml.EndElement{Name: start.Name})
|
|
}
|
|
|
|
// JSONOutputOptions - json output specific options
|
|
type JSONOutputOptions struct {
|
|
RecordDelimiter string
|
|
recordDelimiterSet bool
|
|
}
|
|
|
|
// SetRecordDelimiter sets the record delimiter in the JSON output options
|
|
func (j *JSONOutputOptions) SetRecordDelimiter(val string) {
|
|
j.RecordDelimiter = val
|
|
j.recordDelimiterSet = true
|
|
}
|
|
|
|
// MarshalXML - produces the xml representation of the JSONOutputOptions struct
|
|
func (j JSONOutputOptions) MarshalXML(e *xml.Encoder, start xml.StartElement) error {
|
|
if err := e.EncodeToken(start); err != nil {
|
|
return err
|
|
}
|
|
|
|
if j.RecordDelimiter != "" || j.recordDelimiterSet {
|
|
if err := e.EncodeElement(j.RecordDelimiter, xml.StartElement{Name: xml.Name{Local: "RecordDelimiter"}}); err != nil {
|
|
return err
|
|
}
|
|
}
|
|
|
|
return e.EncodeToken(xml.EndElement{Name: start.Name})
|
|
}
|
|
|
|
// SelectObjectInputSerialization - input serialization parameters
|
|
type SelectObjectInputSerialization struct {
|
|
CompressionType SelectCompressionType `xml:"CompressionType,omitempty"`
|
|
Parquet *ParquetInputOptions `xml:"Parquet,omitempty"`
|
|
CSV *CSVInputOptions `xml:"CSV,omitempty"`
|
|
JSON *JSONInputOptions `xml:"JSON,omitempty"`
|
|
}
|
|
|
|
// SelectObjectOutputSerialization - output serialization parameters.
|
|
type SelectObjectOutputSerialization struct {
|
|
CSV *CSVOutputOptions `xml:"CSV,omitempty"`
|
|
JSON *JSONOutputOptions `xml:"JSON,omitempty"`
|
|
}
|
|
|
|
// SelectObjectOptions - represents the input select body
|
|
type SelectObjectOptions struct {
|
|
XMLName xml.Name `xml:"SelectObjectContentRequest" json:"-"`
|
|
ServerSideEncryption encrypt.ServerSide `xml:"-"`
|
|
Expression string
|
|
ExpressionType QueryExpressionType
|
|
InputSerialization SelectObjectInputSerialization
|
|
OutputSerialization SelectObjectOutputSerialization
|
|
RequestProgress struct {
|
|
Enabled bool
|
|
}
|
|
}
|
|
|
|
// Header returns the http.Header representation of the SelectObject options.
|
|
func (o SelectObjectOptions) Header() http.Header {
|
|
headers := make(http.Header)
|
|
if o.ServerSideEncryption != nil && o.ServerSideEncryption.Type() == encrypt.SSEC {
|
|
o.ServerSideEncryption.Marshal(headers)
|
|
}
|
|
return headers
|
|
}
|
|
|
|
// SelectObjectType - is the parameter which defines what type of object the
|
|
// operation is being performed on.
|
|
type SelectObjectType string
|
|
|
|
// Constants for input data types.
|
|
const (
|
|
SelectObjectTypeCSV SelectObjectType = "CSV"
|
|
SelectObjectTypeJSON = "JSON"
|
|
SelectObjectTypeParquet = "Parquet"
|
|
)
|
|
|
|
// preludeInfo is used for keeping track of necessary information from the
|
|
// prelude.
|
|
type preludeInfo struct {
|
|
totalLen uint32
|
|
headerLen uint32
|
|
}
|
|
|
|
// SelectResults is used for the streaming responses from the server.
|
|
type SelectResults struct {
|
|
pipeReader *io.PipeReader
|
|
resp *http.Response
|
|
stats *StatsMessage
|
|
progress *ProgressMessage
|
|
}
|
|
|
|
// ProgressMessage is a struct for progress xml message.
|
|
type ProgressMessage struct {
|
|
XMLName xml.Name `xml:"Progress" json:"-"`
|
|
StatsMessage
|
|
}
|
|
|
|
// StatsMessage is a struct for stat xml message.
|
|
type StatsMessage struct {
|
|
XMLName xml.Name `xml:"Stats" json:"-"`
|
|
BytesScanned int64
|
|
BytesProcessed int64
|
|
BytesReturned int64
|
|
}
|
|
|
|
// messageType represents the type of message.
|
|
type messageType string
|
|
|
|
const (
|
|
errorMsg messageType = "error"
|
|
commonMsg = "event"
|
|
)
|
|
|
|
// eventType represents the type of event.
|
|
type eventType string
|
|
|
|
// list of event-types returned by Select API.
|
|
const (
|
|
endEvent eventType = "End"
|
|
recordsEvent = "Records"
|
|
progressEvent = "Progress"
|
|
statsEvent = "Stats"
|
|
)
|
|
|
|
// contentType represents content type of event.
|
|
type contentType string
|
|
|
|
const (
|
|
xmlContent contentType = "text/xml"
|
|
)
|
|
|
|
// SelectObjectContent is a implementation of http://docs.aws.amazon.com/AmazonS3/latest/API/RESTObjectSELECTContent.html AWS S3 API.
|
|
func (c *Client) SelectObjectContent(ctx context.Context, bucketName, objectName string, opts SelectObjectOptions) (*SelectResults, error) {
|
|
// Input validation.
|
|
if err := s3utils.CheckValidBucketName(bucketName); err != nil {
|
|
return nil, err
|
|
}
|
|
if err := s3utils.CheckValidObjectName(objectName); err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
selectReqBytes, err := xml.Marshal(opts)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
urlValues := make(url.Values)
|
|
urlValues.Set("select", "")
|
|
urlValues.Set("select-type", "2")
|
|
|
|
// Execute POST on bucket/object.
|
|
resp, err := c.executeMethod(ctx, http.MethodPost, requestMetadata{
|
|
bucketName: bucketName,
|
|
objectName: objectName,
|
|
queryValues: urlValues,
|
|
customHeader: opts.Header(),
|
|
contentMD5Base64: sumMD5Base64(selectReqBytes),
|
|
contentSHA256Hex: sum256Hex(selectReqBytes),
|
|
contentBody: bytes.NewReader(selectReqBytes),
|
|
contentLength: int64(len(selectReqBytes)),
|
|
})
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
return NewSelectResults(resp, bucketName)
|
|
}
|
|
|
|
// NewSelectResults creates a Select Result parser that parses the response
|
|
// and returns a Reader that will return parsed and assembled select output.
|
|
func NewSelectResults(resp *http.Response, bucketName string) (*SelectResults, error) {
|
|
if resp.StatusCode != http.StatusOK {
|
|
return nil, httpRespToErrorResponse(resp, bucketName, "")
|
|
}
|
|
|
|
pipeReader, pipeWriter := io.Pipe()
|
|
streamer := &SelectResults{
|
|
resp: resp,
|
|
stats: &StatsMessage{},
|
|
progress: &ProgressMessage{},
|
|
pipeReader: pipeReader,
|
|
}
|
|
streamer.start(pipeWriter)
|
|
return streamer, nil
|
|
}
|
|
|
|
// Close - closes the underlying response body and the stream reader.
|
|
func (s *SelectResults) Close() error {
|
|
defer closeResponse(s.resp)
|
|
return s.pipeReader.Close()
|
|
}
|
|
|
|
// Read - is a reader compatible implementation for SelectObjectContent records.
|
|
func (s *SelectResults) Read(b []byte) (n int, err error) {
|
|
return s.pipeReader.Read(b)
|
|
}
|
|
|
|
// Stats - information about a request's stats when processing is complete.
|
|
func (s *SelectResults) Stats() *StatsMessage {
|
|
return s.stats
|
|
}
|
|
|
|
// Progress - information about the progress of a request.
|
|
func (s *SelectResults) Progress() *ProgressMessage {
|
|
return s.progress
|
|
}
|
|
|
|
// start is the main function that decodes the large byte array into
|
|
// several events that are sent through the eventstream.
|
|
func (s *SelectResults) start(pipeWriter *io.PipeWriter) {
|
|
go func() {
|
|
for {
|
|
var prelude preludeInfo
|
|
headers := make(http.Header)
|
|
var err error
|
|
|
|
// Create CRC code
|
|
crc := crc32.New(crc32.IEEETable)
|
|
crcReader := io.TeeReader(s.resp.Body, crc)
|
|
|
|
// Extract the prelude(12 bytes) into a struct to extract relevant information.
|
|
prelude, err = processPrelude(crcReader, crc)
|
|
if err != nil {
|
|
pipeWriter.CloseWithError(err)
|
|
closeResponse(s.resp)
|
|
return
|
|
}
|
|
|
|
// Extract the headers(variable bytes) into a struct to extract relevant information
|
|
if prelude.headerLen > 0 {
|
|
if err = extractHeader(io.LimitReader(crcReader, int64(prelude.headerLen)), headers); err != nil {
|
|
pipeWriter.CloseWithError(err)
|
|
closeResponse(s.resp)
|
|
return
|
|
}
|
|
}
|
|
|
|
// Get the actual payload length so that the appropriate amount of
|
|
// bytes can be read or parsed.
|
|
payloadLen := prelude.PayloadLen()
|
|
|
|
m := messageType(headers.Get("message-type"))
|
|
|
|
switch m {
|
|
case errorMsg:
|
|
pipeWriter.CloseWithError(errors.New(headers.Get("error-code") + ":\"" + headers.Get("error-message") + "\""))
|
|
closeResponse(s.resp)
|
|
return
|
|
case commonMsg:
|
|
// Get content-type of the payload.
|
|
c := contentType(headers.Get("content-type"))
|
|
|
|
// Get event type of the payload.
|
|
e := eventType(headers.Get("event-type"))
|
|
|
|
// Handle all supported events.
|
|
switch e {
|
|
case endEvent:
|
|
pipeWriter.Close()
|
|
closeResponse(s.resp)
|
|
return
|
|
case recordsEvent:
|
|
if _, err = io.Copy(pipeWriter, io.LimitReader(crcReader, payloadLen)); err != nil {
|
|
pipeWriter.CloseWithError(err)
|
|
closeResponse(s.resp)
|
|
return
|
|
}
|
|
case progressEvent:
|
|
switch c {
|
|
case xmlContent:
|
|
if err = xmlDecoder(io.LimitReader(crcReader, payloadLen), s.progress); err != nil {
|
|
pipeWriter.CloseWithError(err)
|
|
closeResponse(s.resp)
|
|
return
|
|
}
|
|
default:
|
|
pipeWriter.CloseWithError(fmt.Errorf("Unexpected content-type %s sent for event-type %s", c, progressEvent))
|
|
closeResponse(s.resp)
|
|
return
|
|
}
|
|
case statsEvent:
|
|
switch c {
|
|
case xmlContent:
|
|
if err = xmlDecoder(io.LimitReader(crcReader, payloadLen), s.stats); err != nil {
|
|
pipeWriter.CloseWithError(err)
|
|
closeResponse(s.resp)
|
|
return
|
|
}
|
|
default:
|
|
pipeWriter.CloseWithError(fmt.Errorf("Unexpected content-type %s sent for event-type %s", c, statsEvent))
|
|
closeResponse(s.resp)
|
|
return
|
|
}
|
|
}
|
|
}
|
|
|
|
// Ensures that the full message's CRC is correct and
|
|
// that the message is not corrupted
|
|
if err := checkCRC(s.resp.Body, crc.Sum32()); err != nil {
|
|
pipeWriter.CloseWithError(err)
|
|
closeResponse(s.resp)
|
|
return
|
|
}
|
|
|
|
}
|
|
}()
|
|
}
|
|
|
|
// PayloadLen is a function that calculates the length of the payload.
|
|
func (p preludeInfo) PayloadLen() int64 {
|
|
return int64(p.totalLen - p.headerLen - 16)
|
|
}
|
|
|
|
// processPrelude is the function that reads the 12 bytes of the prelude and
|
|
// ensures the CRC is correct while also extracting relevant information into
|
|
// the struct,
|
|
func processPrelude(prelude io.Reader, crc hash.Hash32) (preludeInfo, error) {
|
|
var err error
|
|
pInfo := preludeInfo{}
|
|
|
|
// reads total length of the message (first 4 bytes)
|
|
pInfo.totalLen, err = extractUint32(prelude)
|
|
if err != nil {
|
|
return pInfo, err
|
|
}
|
|
|
|
// reads total header length of the message (2nd 4 bytes)
|
|
pInfo.headerLen, err = extractUint32(prelude)
|
|
if err != nil {
|
|
return pInfo, err
|
|
}
|
|
|
|
// checks that the CRC is correct (3rd 4 bytes)
|
|
preCRC := crc.Sum32()
|
|
if err := checkCRC(prelude, preCRC); err != nil {
|
|
return pInfo, err
|
|
}
|
|
|
|
return pInfo, nil
|
|
}
|
|
|
|
// extracts the relevant information from the Headers.
|
|
func extractHeader(body io.Reader, myHeaders http.Header) error {
|
|
for {
|
|
// extracts the first part of the header,
|
|
headerTypeName, err := extractHeaderType(body)
|
|
if err != nil {
|
|
// Since end of file, we have read all of our headers
|
|
if err == io.EOF {
|
|
break
|
|
}
|
|
return err
|
|
}
|
|
|
|
// reads the 7 present in the header and ignores it.
|
|
extractUint8(body)
|
|
|
|
headerValueName, err := extractHeaderValue(body)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
myHeaders.Set(headerTypeName, headerValueName)
|
|
|
|
}
|
|
return nil
|
|
}
|
|
|
|
// extractHeaderType extracts the first half of the header message, the header type.
|
|
func extractHeaderType(body io.Reader) (string, error) {
|
|
// extracts 2 bit integer
|
|
headerNameLen, err := extractUint8(body)
|
|
if err != nil {
|
|
return "", err
|
|
}
|
|
// extracts the string with the appropriate number of bytes
|
|
headerName, err := extractString(body, int(headerNameLen))
|
|
if err != nil {
|
|
return "", err
|
|
}
|
|
return strings.TrimPrefix(headerName, ":"), nil
|
|
}
|
|
|
|
// extractsHeaderValue extracts the second half of the header message, the
|
|
// header value
|
|
func extractHeaderValue(body io.Reader) (string, error) {
|
|
bodyLen, err := extractUint16(body)
|
|
if err != nil {
|
|
return "", err
|
|
}
|
|
bodyName, err := extractString(body, int(bodyLen))
|
|
if err != nil {
|
|
return "", err
|
|
}
|
|
return bodyName, nil
|
|
}
|
|
|
|
// extracts a string from byte array of a particular number of bytes.
|
|
func extractString(source io.Reader, lenBytes int) (string, error) {
|
|
myVal := make([]byte, lenBytes)
|
|
_, err := source.Read(myVal)
|
|
if err != nil {
|
|
return "", err
|
|
}
|
|
return string(myVal), nil
|
|
}
|
|
|
|
// extractUint32 extracts a 4 byte integer from the byte array.
|
|
func extractUint32(r io.Reader) (uint32, error) {
|
|
buf := make([]byte, 4)
|
|
_, err := readFull(r, buf)
|
|
if err != nil {
|
|
return 0, err
|
|
}
|
|
return binary.BigEndian.Uint32(buf), nil
|
|
}
|
|
|
|
// extractUint16 extracts a 2 byte integer from the byte array.
|
|
func extractUint16(r io.Reader) (uint16, error) {
|
|
buf := make([]byte, 2)
|
|
_, err := readFull(r, buf)
|
|
if err != nil {
|
|
return 0, err
|
|
}
|
|
return binary.BigEndian.Uint16(buf), nil
|
|
}
|
|
|
|
// extractUint8 extracts a 1 byte integer from the byte array.
|
|
func extractUint8(r io.Reader) (uint8, error) {
|
|
buf := make([]byte, 1)
|
|
_, err := readFull(r, buf)
|
|
if err != nil {
|
|
return 0, err
|
|
}
|
|
return buf[0], nil
|
|
}
|
|
|
|
// checkCRC ensures that the CRC matches with the one from the reader.
|
|
func checkCRC(r io.Reader, expect uint32) error {
|
|
msgCRC, err := extractUint32(r)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
if msgCRC != expect {
|
|
return fmt.Errorf("Checksum Mismatch, MessageCRC of 0x%X does not equal expected CRC of 0x%X", msgCRC, expect)
|
|
}
|
|
return nil
|
|
}
|