Vendor main dependencies.
This commit is contained in:
parent
49a09ab7dd
commit
dd5e3fba01
2738 changed files with 1045689 additions and 0 deletions
761
vendor/gopkg.in/mgo.v2/gridfs.go
generated
vendored
Normal file
761
vendor/gopkg.in/mgo.v2/gridfs.go
generated
vendored
Normal file
|
@ -0,0 +1,761 @@
|
|||
// mgo - MongoDB driver for Go
|
||||
//
|
||||
// Copyright (c) 2010-2012 - Gustavo Niemeyer <gustavo@niemeyer.net>
|
||||
//
|
||||
// All rights reserved.
|
||||
//
|
||||
// Redistribution and use in source and binary forms, with or without
|
||||
// modification, are permitted provided that the following conditions are met:
|
||||
//
|
||||
// 1. Redistributions of source code must retain the above copyright notice, this
|
||||
// list of conditions and the following disclaimer.
|
||||
// 2. Redistributions in binary form must reproduce the above copyright notice,
|
||||
// this list of conditions and the following disclaimer in the documentation
|
||||
// and/or other materials provided with the distribution.
|
||||
//
|
||||
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
|
||||
// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
|
||||
// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
|
||||
// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
|
||||
// ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
|
||||
// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
|
||||
// LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
|
||||
// ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
||||
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
|
||||
// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
||||
|
||||
package mgo
|
||||
|
||||
import (
|
||||
"crypto/md5"
|
||||
"encoding/hex"
|
||||
"errors"
|
||||
"hash"
|
||||
"io"
|
||||
"os"
|
||||
"sync"
|
||||
"time"
|
||||
|
||||
"gopkg.in/mgo.v2/bson"
|
||||
)
|
||||
|
||||
type GridFS struct {
|
||||
Files *Collection
|
||||
Chunks *Collection
|
||||
}
|
||||
|
||||
type gfsFileMode int
|
||||
|
||||
const (
|
||||
gfsClosed gfsFileMode = 0
|
||||
gfsReading gfsFileMode = 1
|
||||
gfsWriting gfsFileMode = 2
|
||||
)
|
||||
|
||||
type GridFile struct {
|
||||
m sync.Mutex
|
||||
c sync.Cond
|
||||
gfs *GridFS
|
||||
mode gfsFileMode
|
||||
err error
|
||||
|
||||
chunk int
|
||||
offset int64
|
||||
|
||||
wpending int
|
||||
wbuf []byte
|
||||
wsum hash.Hash
|
||||
|
||||
rbuf []byte
|
||||
rcache *gfsCachedChunk
|
||||
|
||||
doc gfsFile
|
||||
}
|
||||
|
||||
type gfsFile struct {
|
||||
Id interface{} "_id"
|
||||
ChunkSize int "chunkSize"
|
||||
UploadDate time.Time "uploadDate"
|
||||
Length int64 ",minsize"
|
||||
MD5 string
|
||||
Filename string ",omitempty"
|
||||
ContentType string "contentType,omitempty"
|
||||
Metadata *bson.Raw ",omitempty"
|
||||
}
|
||||
|
||||
type gfsChunk struct {
|
||||
Id interface{} "_id"
|
||||
FilesId interface{} "files_id"
|
||||
N int
|
||||
Data []byte
|
||||
}
|
||||
|
||||
type gfsCachedChunk struct {
|
||||
wait sync.Mutex
|
||||
n int
|
||||
data []byte
|
||||
err error
|
||||
}
|
||||
|
||||
func newGridFS(db *Database, prefix string) *GridFS {
|
||||
return &GridFS{db.C(prefix + ".files"), db.C(prefix + ".chunks")}
|
||||
}
|
||||
|
||||
func (gfs *GridFS) newFile() *GridFile {
|
||||
file := &GridFile{gfs: gfs}
|
||||
file.c.L = &file.m
|
||||
//runtime.SetFinalizer(file, finalizeFile)
|
||||
return file
|
||||
}
|
||||
|
||||
func finalizeFile(file *GridFile) {
|
||||
file.Close()
|
||||
}
|
||||
|
||||
// Create creates a new file with the provided name in the GridFS. If the file
|
||||
// name already exists, a new version will be inserted with an up-to-date
|
||||
// uploadDate that will cause it to be atomically visible to the Open and
|
||||
// OpenId methods. If the file name is not important, an empty name may be
|
||||
// provided and the file Id used instead.
|
||||
//
|
||||
// It's important to Close files whether they are being written to
|
||||
// or read from, and to check the err result to ensure the operation
|
||||
// completed successfully.
|
||||
//
|
||||
// A simple example inserting a new file:
|
||||
//
|
||||
// func check(err error) {
|
||||
// if err != nil {
|
||||
// panic(err.String())
|
||||
// }
|
||||
// }
|
||||
// file, err := db.GridFS("fs").Create("myfile.txt")
|
||||
// check(err)
|
||||
// n, err := file.Write([]byte("Hello world!"))
|
||||
// check(err)
|
||||
// err = file.Close()
|
||||
// check(err)
|
||||
// fmt.Printf("%d bytes written\n", n)
|
||||
//
|
||||
// The io.Writer interface is implemented by *GridFile and may be used to
|
||||
// help on the file creation. For example:
|
||||
//
|
||||
// file, err := db.GridFS("fs").Create("myfile.txt")
|
||||
// check(err)
|
||||
// messages, err := os.Open("/var/log/messages")
|
||||
// check(err)
|
||||
// defer messages.Close()
|
||||
// err = io.Copy(file, messages)
|
||||
// check(err)
|
||||
// err = file.Close()
|
||||
// check(err)
|
||||
//
|
||||
func (gfs *GridFS) Create(name string) (file *GridFile, err error) {
|
||||
file = gfs.newFile()
|
||||
file.mode = gfsWriting
|
||||
file.wsum = md5.New()
|
||||
file.doc = gfsFile{Id: bson.NewObjectId(), ChunkSize: 255 * 1024, Filename: name}
|
||||
return
|
||||
}
|
||||
|
||||
// OpenId returns the file with the provided id, for reading.
|
||||
// If the file isn't found, err will be set to mgo.ErrNotFound.
|
||||
//
|
||||
// It's important to Close files whether they are being written to
|
||||
// or read from, and to check the err result to ensure the operation
|
||||
// completed successfully.
|
||||
//
|
||||
// The following example will print the first 8192 bytes from the file:
|
||||
//
|
||||
// func check(err error) {
|
||||
// if err != nil {
|
||||
// panic(err.String())
|
||||
// }
|
||||
// }
|
||||
// file, err := db.GridFS("fs").OpenId(objid)
|
||||
// check(err)
|
||||
// b := make([]byte, 8192)
|
||||
// n, err := file.Read(b)
|
||||
// check(err)
|
||||
// fmt.Println(string(b))
|
||||
// check(err)
|
||||
// err = file.Close()
|
||||
// check(err)
|
||||
// fmt.Printf("%d bytes read\n", n)
|
||||
//
|
||||
// The io.Reader interface is implemented by *GridFile and may be used to
|
||||
// deal with it. As an example, the following snippet will dump the whole
|
||||
// file into the standard output:
|
||||
//
|
||||
// file, err := db.GridFS("fs").OpenId(objid)
|
||||
// check(err)
|
||||
// err = io.Copy(os.Stdout, file)
|
||||
// check(err)
|
||||
// err = file.Close()
|
||||
// check(err)
|
||||
//
|
||||
func (gfs *GridFS) OpenId(id interface{}) (file *GridFile, err error) {
|
||||
var doc gfsFile
|
||||
err = gfs.Files.Find(bson.M{"_id": id}).One(&doc)
|
||||
if err != nil {
|
||||
return
|
||||
}
|
||||
file = gfs.newFile()
|
||||
file.mode = gfsReading
|
||||
file.doc = doc
|
||||
return
|
||||
}
|
||||
|
||||
// Open returns the most recently uploaded file with the provided
|
||||
// name, for reading. If the file isn't found, err will be set
|
||||
// to mgo.ErrNotFound.
|
||||
//
|
||||
// It's important to Close files whether they are being written to
|
||||
// or read from, and to check the err result to ensure the operation
|
||||
// completed successfully.
|
||||
//
|
||||
// The following example will print the first 8192 bytes from the file:
|
||||
//
|
||||
// file, err := db.GridFS("fs").Open("myfile.txt")
|
||||
// check(err)
|
||||
// b := make([]byte, 8192)
|
||||
// n, err := file.Read(b)
|
||||
// check(err)
|
||||
// fmt.Println(string(b))
|
||||
// check(err)
|
||||
// err = file.Close()
|
||||
// check(err)
|
||||
// fmt.Printf("%d bytes read\n", n)
|
||||
//
|
||||
// The io.Reader interface is implemented by *GridFile and may be used to
|
||||
// deal with it. As an example, the following snippet will dump the whole
|
||||
// file into the standard output:
|
||||
//
|
||||
// file, err := db.GridFS("fs").Open("myfile.txt")
|
||||
// check(err)
|
||||
// err = io.Copy(os.Stdout, file)
|
||||
// check(err)
|
||||
// err = file.Close()
|
||||
// check(err)
|
||||
//
|
||||
func (gfs *GridFS) Open(name string) (file *GridFile, err error) {
|
||||
var doc gfsFile
|
||||
err = gfs.Files.Find(bson.M{"filename": name}).Sort("-uploadDate").One(&doc)
|
||||
if err != nil {
|
||||
return
|
||||
}
|
||||
file = gfs.newFile()
|
||||
file.mode = gfsReading
|
||||
file.doc = doc
|
||||
return
|
||||
}
|
||||
|
||||
// OpenNext opens the next file from iter for reading, sets *file to it,
|
||||
// and returns true on the success case. If no more documents are available
|
||||
// on iter or an error occurred, *file is set to nil and the result is false.
|
||||
// Errors will be available via iter.Err().
|
||||
//
|
||||
// The iter parameter must be an iterator on the GridFS files collection.
|
||||
// Using the GridFS.Find method is an easy way to obtain such an iterator,
|
||||
// but any iterator on the collection will work.
|
||||
//
|
||||
// If the provided *file is non-nil, OpenNext will close it before attempting
|
||||
// to iterate to the next element. This means that in a loop one only
|
||||
// has to worry about closing files when breaking out of the loop early
|
||||
// (break, return, or panic).
|
||||
//
|
||||
// For example:
|
||||
//
|
||||
// gfs := db.GridFS("fs")
|
||||
// query := gfs.Find(nil).Sort("filename")
|
||||
// iter := query.Iter()
|
||||
// var f *mgo.GridFile
|
||||
// for gfs.OpenNext(iter, &f) {
|
||||
// fmt.Printf("Filename: %s\n", f.Name())
|
||||
// }
|
||||
// if iter.Close() != nil {
|
||||
// panic(iter.Close())
|
||||
// }
|
||||
//
|
||||
func (gfs *GridFS) OpenNext(iter *Iter, file **GridFile) bool {
|
||||
if *file != nil {
|
||||
// Ignoring the error here shouldn't be a big deal
|
||||
// as we're reading the file and the loop iteration
|
||||
// for this file is finished.
|
||||
_ = (*file).Close()
|
||||
}
|
||||
var doc gfsFile
|
||||
if !iter.Next(&doc) {
|
||||
*file = nil
|
||||
return false
|
||||
}
|
||||
f := gfs.newFile()
|
||||
f.mode = gfsReading
|
||||
f.doc = doc
|
||||
*file = f
|
||||
return true
|
||||
}
|
||||
|
||||
// Find runs query on GridFS's files collection and returns
|
||||
// the resulting Query.
|
||||
//
|
||||
// This logic:
|
||||
//
|
||||
// gfs := db.GridFS("fs")
|
||||
// iter := gfs.Find(nil).Iter()
|
||||
//
|
||||
// Is equivalent to:
|
||||
//
|
||||
// files := db.C("fs" + ".files")
|
||||
// iter := files.Find(nil).Iter()
|
||||
//
|
||||
func (gfs *GridFS) Find(query interface{}) *Query {
|
||||
return gfs.Files.Find(query)
|
||||
}
|
||||
|
||||
// RemoveId deletes the file with the provided id from the GridFS.
|
||||
func (gfs *GridFS) RemoveId(id interface{}) error {
|
||||
err := gfs.Files.Remove(bson.M{"_id": id})
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
_, err = gfs.Chunks.RemoveAll(bson.D{{"files_id", id}})
|
||||
return err
|
||||
}
|
||||
|
||||
type gfsDocId struct {
|
||||
Id interface{} "_id"
|
||||
}
|
||||
|
||||
// Remove deletes all files with the provided name from the GridFS.
|
||||
func (gfs *GridFS) Remove(name string) (err error) {
|
||||
iter := gfs.Files.Find(bson.M{"filename": name}).Select(bson.M{"_id": 1}).Iter()
|
||||
var doc gfsDocId
|
||||
for iter.Next(&doc) {
|
||||
if e := gfs.RemoveId(doc.Id); e != nil {
|
||||
err = e
|
||||
}
|
||||
}
|
||||
if err == nil {
|
||||
err = iter.Close()
|
||||
}
|
||||
return err
|
||||
}
|
||||
|
||||
func (file *GridFile) assertMode(mode gfsFileMode) {
|
||||
switch file.mode {
|
||||
case mode:
|
||||
return
|
||||
case gfsWriting:
|
||||
panic("GridFile is open for writing")
|
||||
case gfsReading:
|
||||
panic("GridFile is open for reading")
|
||||
case gfsClosed:
|
||||
panic("GridFile is closed")
|
||||
default:
|
||||
panic("internal error: missing GridFile mode")
|
||||
}
|
||||
}
|
||||
|
||||
// SetChunkSize sets size of saved chunks. Once the file is written to, it
|
||||
// will be split in blocks of that size and each block saved into an
|
||||
// independent chunk document. The default chunk size is 256kb.
|
||||
//
|
||||
// It is a runtime error to call this function once the file has started
|
||||
// being written to.
|
||||
func (file *GridFile) SetChunkSize(bytes int) {
|
||||
file.assertMode(gfsWriting)
|
||||
debugf("GridFile %p: setting chunk size to %d", file, bytes)
|
||||
file.m.Lock()
|
||||
file.doc.ChunkSize = bytes
|
||||
file.m.Unlock()
|
||||
}
|
||||
|
||||
// Id returns the current file Id.
|
||||
func (file *GridFile) Id() interface{} {
|
||||
return file.doc.Id
|
||||
}
|
||||
|
||||
// SetId changes the current file Id.
|
||||
//
|
||||
// It is a runtime error to call this function once the file has started
|
||||
// being written to, or when the file is not open for writing.
|
||||
func (file *GridFile) SetId(id interface{}) {
|
||||
file.assertMode(gfsWriting)
|
||||
file.m.Lock()
|
||||
file.doc.Id = id
|
||||
file.m.Unlock()
|
||||
}
|
||||
|
||||
// Name returns the optional file name. An empty string will be returned
|
||||
// in case it is unset.
|
||||
func (file *GridFile) Name() string {
|
||||
return file.doc.Filename
|
||||
}
|
||||
|
||||
// SetName changes the optional file name. An empty string may be used to
|
||||
// unset it.
|
||||
//
|
||||
// It is a runtime error to call this function when the file is not open
|
||||
// for writing.
|
||||
func (file *GridFile) SetName(name string) {
|
||||
file.assertMode(gfsWriting)
|
||||
file.m.Lock()
|
||||
file.doc.Filename = name
|
||||
file.m.Unlock()
|
||||
}
|
||||
|
||||
// ContentType returns the optional file content type. An empty string will be
|
||||
// returned in case it is unset.
|
||||
func (file *GridFile) ContentType() string {
|
||||
return file.doc.ContentType
|
||||
}
|
||||
|
||||
// ContentType changes the optional file content type. An empty string may be
|
||||
// used to unset it.
|
||||
//
|
||||
// It is a runtime error to call this function when the file is not open
|
||||
// for writing.
|
||||
func (file *GridFile) SetContentType(ctype string) {
|
||||
file.assertMode(gfsWriting)
|
||||
file.m.Lock()
|
||||
file.doc.ContentType = ctype
|
||||
file.m.Unlock()
|
||||
}
|
||||
|
||||
// GetMeta unmarshals the optional "metadata" field associated with the
|
||||
// file into the result parameter. The meaning of keys under that field
|
||||
// is user-defined. For example:
|
||||
//
|
||||
// result := struct{ INode int }{}
|
||||
// err = file.GetMeta(&result)
|
||||
// if err != nil {
|
||||
// panic(err.String())
|
||||
// }
|
||||
// fmt.Printf("inode: %d\n", result.INode)
|
||||
//
|
||||
func (file *GridFile) GetMeta(result interface{}) (err error) {
|
||||
file.m.Lock()
|
||||
if file.doc.Metadata != nil {
|
||||
err = bson.Unmarshal(file.doc.Metadata.Data, result)
|
||||
}
|
||||
file.m.Unlock()
|
||||
return
|
||||
}
|
||||
|
||||
// SetMeta changes the optional "metadata" field associated with the
|
||||
// file. The meaning of keys under that field is user-defined.
|
||||
// For example:
|
||||
//
|
||||
// file.SetMeta(bson.M{"inode": inode})
|
||||
//
|
||||
// It is a runtime error to call this function when the file is not open
|
||||
// for writing.
|
||||
func (file *GridFile) SetMeta(metadata interface{}) {
|
||||
file.assertMode(gfsWriting)
|
||||
data, err := bson.Marshal(metadata)
|
||||
file.m.Lock()
|
||||
if err != nil && file.err == nil {
|
||||
file.err = err
|
||||
} else {
|
||||
file.doc.Metadata = &bson.Raw{Data: data}
|
||||
}
|
||||
file.m.Unlock()
|
||||
}
|
||||
|
||||
// Size returns the file size in bytes.
|
||||
func (file *GridFile) Size() (bytes int64) {
|
||||
file.m.Lock()
|
||||
bytes = file.doc.Length
|
||||
file.m.Unlock()
|
||||
return
|
||||
}
|
||||
|
||||
// MD5 returns the file MD5 as a hex-encoded string.
|
||||
func (file *GridFile) MD5() (md5 string) {
|
||||
return file.doc.MD5
|
||||
}
|
||||
|
||||
// UploadDate returns the file upload time.
|
||||
func (file *GridFile) UploadDate() time.Time {
|
||||
return file.doc.UploadDate
|
||||
}
|
||||
|
||||
// SetUploadDate changes the file upload time.
|
||||
//
|
||||
// It is a runtime error to call this function when the file is not open
|
||||
// for writing.
|
||||
func (file *GridFile) SetUploadDate(t time.Time) {
|
||||
file.assertMode(gfsWriting)
|
||||
file.m.Lock()
|
||||
file.doc.UploadDate = t
|
||||
file.m.Unlock()
|
||||
}
|
||||
|
||||
// Close flushes any pending changes in case the file is being written
|
||||
// to, waits for any background operations to finish, and closes the file.
|
||||
//
|
||||
// It's important to Close files whether they are being written to
|
||||
// or read from, and to check the err result to ensure the operation
|
||||
// completed successfully.
|
||||
func (file *GridFile) Close() (err error) {
|
||||
file.m.Lock()
|
||||
defer file.m.Unlock()
|
||||
if file.mode == gfsWriting {
|
||||
if len(file.wbuf) > 0 && file.err == nil {
|
||||
file.insertChunk(file.wbuf)
|
||||
file.wbuf = file.wbuf[0:0]
|
||||
}
|
||||
file.completeWrite()
|
||||
} else if file.mode == gfsReading && file.rcache != nil {
|
||||
file.rcache.wait.Lock()
|
||||
file.rcache = nil
|
||||
}
|
||||
file.mode = gfsClosed
|
||||
debugf("GridFile %p: closed", file)
|
||||
return file.err
|
||||
}
|
||||
|
||||
func (file *GridFile) completeWrite() {
|
||||
for file.wpending > 0 {
|
||||
debugf("GridFile %p: waiting for %d pending chunks to complete file write", file, file.wpending)
|
||||
file.c.Wait()
|
||||
}
|
||||
if file.err == nil {
|
||||
hexsum := hex.EncodeToString(file.wsum.Sum(nil))
|
||||
if file.doc.UploadDate.IsZero() {
|
||||
file.doc.UploadDate = bson.Now()
|
||||
}
|
||||
file.doc.MD5 = hexsum
|
||||
file.err = file.gfs.Files.Insert(file.doc)
|
||||
}
|
||||
if file.err != nil {
|
||||
file.gfs.Chunks.RemoveAll(bson.D{{"files_id", file.doc.Id}})
|
||||
}
|
||||
if file.err == nil {
|
||||
index := Index{
|
||||
Key: []string{"files_id", "n"},
|
||||
Unique: true,
|
||||
}
|
||||
file.err = file.gfs.Chunks.EnsureIndex(index)
|
||||
}
|
||||
}
|
||||
|
||||
// Abort cancels an in-progress write, preventing the file from being
|
||||
// automically created and ensuring previously written chunks are
|
||||
// removed when the file is closed.
|
||||
//
|
||||
// It is a runtime error to call Abort when the file was not opened
|
||||
// for writing.
|
||||
func (file *GridFile) Abort() {
|
||||
if file.mode != gfsWriting {
|
||||
panic("file.Abort must be called on file opened for writing")
|
||||
}
|
||||
file.err = errors.New("write aborted")
|
||||
}
|
||||
|
||||
// Write writes the provided data to the file and returns the
|
||||
// number of bytes written and an error in case something
|
||||
// wrong happened.
|
||||
//
|
||||
// The file will internally cache the data so that all but the last
|
||||
// chunk sent to the database have the size defined by SetChunkSize.
|
||||
// This also means that errors may be deferred until a future call
|
||||
// to Write or Close.
|
||||
//
|
||||
// The parameters and behavior of this function turn the file
|
||||
// into an io.Writer.
|
||||
func (file *GridFile) Write(data []byte) (n int, err error) {
|
||||
file.assertMode(gfsWriting)
|
||||
file.m.Lock()
|
||||
debugf("GridFile %p: writing %d bytes", file, len(data))
|
||||
defer file.m.Unlock()
|
||||
|
||||
if file.err != nil {
|
||||
return 0, file.err
|
||||
}
|
||||
|
||||
n = len(data)
|
||||
file.doc.Length += int64(n)
|
||||
chunkSize := file.doc.ChunkSize
|
||||
|
||||
if len(file.wbuf)+len(data) < chunkSize {
|
||||
file.wbuf = append(file.wbuf, data...)
|
||||
return
|
||||
}
|
||||
|
||||
// First, flush file.wbuf complementing with data.
|
||||
if len(file.wbuf) > 0 {
|
||||
missing := chunkSize - len(file.wbuf)
|
||||
if missing > len(data) {
|
||||
missing = len(data)
|
||||
}
|
||||
file.wbuf = append(file.wbuf, data[:missing]...)
|
||||
data = data[missing:]
|
||||
file.insertChunk(file.wbuf)
|
||||
file.wbuf = file.wbuf[0:0]
|
||||
}
|
||||
|
||||
// Then, flush all chunks from data without copying.
|
||||
for len(data) > chunkSize {
|
||||
size := chunkSize
|
||||
if size > len(data) {
|
||||
size = len(data)
|
||||
}
|
||||
file.insertChunk(data[:size])
|
||||
data = data[size:]
|
||||
}
|
||||
|
||||
// And append the rest for a future call.
|
||||
file.wbuf = append(file.wbuf, data...)
|
||||
|
||||
return n, file.err
|
||||
}
|
||||
|
||||
func (file *GridFile) insertChunk(data []byte) {
|
||||
n := file.chunk
|
||||
file.chunk++
|
||||
debugf("GridFile %p: adding to checksum: %q", file, string(data))
|
||||
file.wsum.Write(data)
|
||||
|
||||
for file.doc.ChunkSize*file.wpending >= 1024*1024 {
|
||||
// Hold on.. we got a MB pending.
|
||||
file.c.Wait()
|
||||
if file.err != nil {
|
||||
return
|
||||
}
|
||||
}
|
||||
|
||||
file.wpending++
|
||||
|
||||
debugf("GridFile %p: inserting chunk %d with %d bytes", file, n, len(data))
|
||||
|
||||
// We may not own the memory of data, so rather than
|
||||
// simply copying it, we'll marshal the document ahead of time.
|
||||
data, err := bson.Marshal(gfsChunk{bson.NewObjectId(), file.doc.Id, n, data})
|
||||
if err != nil {
|
||||
file.err = err
|
||||
return
|
||||
}
|
||||
|
||||
go func() {
|
||||
err := file.gfs.Chunks.Insert(bson.Raw{Data: data})
|
||||
file.m.Lock()
|
||||
file.wpending--
|
||||
if err != nil && file.err == nil {
|
||||
file.err = err
|
||||
}
|
||||
file.c.Broadcast()
|
||||
file.m.Unlock()
|
||||
}()
|
||||
}
|
||||
|
||||
// Seek sets the offset for the next Read or Write on file to
|
||||
// offset, interpreted according to whence: 0 means relative to
|
||||
// the origin of the file, 1 means relative to the current offset,
|
||||
// and 2 means relative to the end. It returns the new offset and
|
||||
// an error, if any.
|
||||
func (file *GridFile) Seek(offset int64, whence int) (pos int64, err error) {
|
||||
file.m.Lock()
|
||||
debugf("GridFile %p: seeking for %s (whence=%d)", file, offset, whence)
|
||||
defer file.m.Unlock()
|
||||
switch whence {
|
||||
case os.SEEK_SET:
|
||||
case os.SEEK_CUR:
|
||||
offset += file.offset
|
||||
case os.SEEK_END:
|
||||
offset += file.doc.Length
|
||||
default:
|
||||
panic("unsupported whence value")
|
||||
}
|
||||
if offset > file.doc.Length {
|
||||
return file.offset, errors.New("seek past end of file")
|
||||
}
|
||||
if offset == file.doc.Length {
|
||||
// If we're seeking to the end of the file,
|
||||
// no need to read anything. This enables
|
||||
// a client to find the size of the file using only the
|
||||
// io.ReadSeeker interface with low overhead.
|
||||
file.offset = offset
|
||||
return file.offset, nil
|
||||
}
|
||||
chunk := int(offset / int64(file.doc.ChunkSize))
|
||||
if chunk+1 == file.chunk && offset >= file.offset {
|
||||
file.rbuf = file.rbuf[int(offset-file.offset):]
|
||||
file.offset = offset
|
||||
return file.offset, nil
|
||||
}
|
||||
file.offset = offset
|
||||
file.chunk = chunk
|
||||
file.rbuf = nil
|
||||
file.rbuf, err = file.getChunk()
|
||||
if err == nil {
|
||||
file.rbuf = file.rbuf[int(file.offset-int64(chunk)*int64(file.doc.ChunkSize)):]
|
||||
}
|
||||
return file.offset, err
|
||||
}
|
||||
|
||||
// Read reads into b the next available data from the file and
|
||||
// returns the number of bytes written and an error in case
|
||||
// something wrong happened. At the end of the file, n will
|
||||
// be zero and err will be set to io.EOF.
|
||||
//
|
||||
// The parameters and behavior of this function turn the file
|
||||
// into an io.Reader.
|
||||
func (file *GridFile) Read(b []byte) (n int, err error) {
|
||||
file.assertMode(gfsReading)
|
||||
file.m.Lock()
|
||||
debugf("GridFile %p: reading at offset %d into buffer of length %d", file, file.offset, len(b))
|
||||
defer file.m.Unlock()
|
||||
if file.offset == file.doc.Length {
|
||||
return 0, io.EOF
|
||||
}
|
||||
for err == nil {
|
||||
i := copy(b, file.rbuf)
|
||||
n += i
|
||||
file.offset += int64(i)
|
||||
file.rbuf = file.rbuf[i:]
|
||||
if i == len(b) || file.offset == file.doc.Length {
|
||||
break
|
||||
}
|
||||
b = b[i:]
|
||||
file.rbuf, err = file.getChunk()
|
||||
}
|
||||
return n, err
|
||||
}
|
||||
|
||||
func (file *GridFile) getChunk() (data []byte, err error) {
|
||||
cache := file.rcache
|
||||
file.rcache = nil
|
||||
if cache != nil && cache.n == file.chunk {
|
||||
debugf("GridFile %p: Getting chunk %d from cache", file, file.chunk)
|
||||
cache.wait.Lock()
|
||||
data, err = cache.data, cache.err
|
||||
} else {
|
||||
debugf("GridFile %p: Fetching chunk %d", file, file.chunk)
|
||||
var doc gfsChunk
|
||||
err = file.gfs.Chunks.Find(bson.D{{"files_id", file.doc.Id}, {"n", file.chunk}}).One(&doc)
|
||||
data = doc.Data
|
||||
}
|
||||
file.chunk++
|
||||
if int64(file.chunk)*int64(file.doc.ChunkSize) < file.doc.Length {
|
||||
// Read the next one in background.
|
||||
cache = &gfsCachedChunk{n: file.chunk}
|
||||
cache.wait.Lock()
|
||||
debugf("GridFile %p: Scheduling chunk %d for background caching", file, file.chunk)
|
||||
// Clone the session to avoid having it closed in between.
|
||||
chunks := file.gfs.Chunks
|
||||
session := chunks.Database.Session.Clone()
|
||||
go func(id interface{}, n int) {
|
||||
defer session.Close()
|
||||
chunks = chunks.With(session)
|
||||
var doc gfsChunk
|
||||
cache.err = chunks.Find(bson.D{{"files_id", id}, {"n", n}}).One(&doc)
|
||||
cache.data = doc.Data
|
||||
cache.wait.Unlock()
|
||||
}(file.doc.Id, file.chunk)
|
||||
file.rcache = cache
|
||||
}
|
||||
debugf("Returning err: %#v", err)
|
||||
return
|
||||
}
|
Loading…
Add table
Add a link
Reference in a new issue