goofysでS3をUbuntuにマウントする

### バージョン確認
```
$ cat /etc/lsb-release
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=18.04
DISTRIB_CODENAME=bionic
DISTRIB_DESCRIPTION="Ubuntu 18.04.5 LTS"
```

## goofysのインストール
Golang環境を構築して，ソースから入れることもできるようではある．
しかし自分が再現しようとしたところ，[公式のREADME.md](https://github.com/kahing/goofys)の

```
$ go get github.com/kahing/goofys
```

のところで詰まった．
2020年4月くらいに更新が止まっているので，そのままバイナリを落としていれることにする．

pre-buildバイナリファイルを落として，

```
$ mv path-to-pre-build-binary-of-goofys ~/.local/bin
$ chmod +x ~/.local/bin
$ goofys
Error: goofys takes exactly two arguments.

NAME:
   goofys - Mount an S3 bucket locally

USAGE:
   goofys [global options] bucket[:prefix] mountpoint

VERSION:
   0.24.0-45b8d78375af1b24604439d2e60c567654bcdf88

GLOBAL OPTIONS:
   -o value            Additional system-specific mount options. Be careful!
   --cache value       Directory to use for data cache. Requires catfs and `-o allow_other'. Can also pass in other catfs options (ex: --cache "--free:10%:$HOME/cache") (default: off)
   --dir-mode value    Permission bits for directories. (default: 0755) (default: 493)
   --file-mode value   Permission bits for files. (default: 0644) (default: 420)
   --uid value         UID owner of all inodes. (default: 1000)
   --gid value         GID owner of all inodes. (default: 1000)
   --endpoint value    The non-AWS endpoint to connect to. Possible values: http://127.0.0.1:8081/
   --profile value     Use a named profile from $HOME/.aws/credentials instead of "default"
   --use-content-type  Set Content-Type according to file extension and /etc/mime.types (default: off)
   --subdomain         Enable subdomain mode of S3

TUNING OPTIONS:
   --cheap                 Reduce S3 operation costs at the expense of some performance (default: off)
   --no-implicit-dir       Assume all directory objects ("dir/") exist (default: off)
   --stat-cache-ttl value  How long to cache StatObject results and inode attributes. (default: 1m0s)
   --type-cache-ttl value  How long to cache name -> file/dir mappings in directory inodes. (default: 1m0s)
   --http-timeout value    Set the timeout on HTTP requests to S3 (default: 30s)

AWS S3 OPTIONS:
   --region value         The region to connect to. Usually this is auto-detected. Possible values: us-east-1, us-west-1, us-west-2, eu-west-1, eu-central-1, ap-southeast-1, ap-southeast-2, ap-northeast-1, sa-east-1, cn-north-1 (default: "us-east-1")
   --requester-pays       Whether to allow access to requester-pays buckets (default: off)
   --storage-class value  The type of storage to use when writing objects. Possible values: REDUCED_REDUNDANCY, STANDARD, STANDARD_IA. (default: "STANDARD")
   --sse                  Enable basic server-side encryption at rest (SSE-S3) in S3 for all writes (default: off)
   --sse-kms key-id       Enable KMS encryption (SSE-KMS) for all writes using this particular KMS key-id. Leave blank to Use the account's CMK - customer master key (default: off)
   --sse-c value          Enable server-side encryption using this base64-encoded key (default: off)
   --acl value            The canned ACL to apply to the object. Possible values: private, public-read, public-read-write, authenticated-read, aws-exec-read, bucket-owner-read, bucket-owner-full-control (default: off)

MISC OPTIONS:
   --help, -h     Print this help text and exit successfully.
   --debug_fuse   Enable fuse-related debugging output.
   --debug_s3     Enable S3-related debugging output.
   -f             Run goofys in foreground.
   --version, -v  print the version
```

### AWS Credentialの確認
```
$ cat ~/.aws/credentials
[default]
aws_access_key_id = AKID1234567890
aws_secret_access_key = MY-SECRET-KEY
```
もちろん，このアカウントにマウントしたいS3バケットの権限が与えられている必要がある．

### S3バケットのマウント
```
$ goofys <bucket> <mountpoint>
```

## 参考
* [公式Github](https://github.com/kahing/goofys)