GoToSocial/vendor/github.com/minio/minio-go/v7/api-get-object-file.go
Dominik Süß 9d0df426da
[feature] S3 support (#674)
* 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
2022-07-03 12:08:30 +02:00

128 lines
3.4 KiB
Go

/*
* MinIO Go Library for Amazon S3 Compatible Cloud Storage
* Copyright 2015-2017 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 (
"context"
"io"
"os"
"path/filepath"
"github.com/minio/minio-go/v7/pkg/s3utils"
)
// FGetObject - download contents of an object to a local file.
// The options can be used to specify the GET request further.
func (c *Client) FGetObject(ctx context.Context, bucketName, objectName, filePath string, opts GetObjectOptions) error {
// Input validation.
if err := s3utils.CheckValidBucketName(bucketName); err != nil {
return err
}
if err := s3utils.CheckValidObjectName(objectName); err != nil {
return err
}
// Verify if destination already exists.
st, err := os.Stat(filePath)
if err == nil {
// If the destination exists and is a directory.
if st.IsDir() {
return errInvalidArgument("fileName is a directory.")
}
}
// Proceed if file does not exist. return for all other errors.
if err != nil {
if !os.IsNotExist(err) {
return err
}
}
// Extract top level directory.
objectDir, _ := filepath.Split(filePath)
if objectDir != "" {
// Create any missing top level directories.
if err := os.MkdirAll(objectDir, 0o700); err != nil {
return err
}
}
// Gather md5sum.
objectStat, err := c.StatObject(ctx, bucketName, objectName, StatObjectOptions(opts))
if err != nil {
return err
}
// Write to a temporary file "fileName.part.minio" before saving.
filePartPath := filePath + objectStat.ETag + ".part.minio"
// If exists, open in append mode. If not create it as a part file.
filePart, err := os.OpenFile(filePartPath, os.O_CREATE|os.O_APPEND|os.O_WRONLY, 0o600)
if err != nil {
return err
}
// If we return early with an error, be sure to close and delete
// filePart. If we have an error along the way there is a chance
// that filePart is somehow damaged, and we should discard it.
closeAndRemove := true
defer func() {
if closeAndRemove {
_ = filePart.Close()
_ = os.Remove(filePartPath)
}
}()
// Issue Stat to get the current offset.
st, err = filePart.Stat()
if err != nil {
return err
}
// Initialize get object request headers to set the
// appropriate range offsets to read from.
if st.Size() > 0 {
opts.SetRange(st.Size(), 0)
}
// Seek to current position for incoming reader.
objectReader, objectStat, _, err := c.getObject(ctx, bucketName, objectName, opts)
if err != nil {
return err
}
// Write to the part file.
if _, err = io.CopyN(filePart, objectReader, objectStat.Size); err != nil {
return err
}
// Close the file before rename, this is specifically needed for Windows users.
closeAndRemove = false
if err = filePart.Close(); err != nil {
return err
}
// Safely completed. Now commit by renaming to actual filename.
if err = os.Rename(filePartPath, filePath); err != nil {
return err
}
// Return.
return nil
}