对象存储演练

NOTICE: Experimental Preview

Prerequisite: enabling JetStream

If you are running a local nats-server stop it and restart it with JetStream enabled using nats-server -js (if that's not already done)

You can then check that JetStream is enabled by using

nats account info

Which should output something like:

Connection Information:

               Client ID: 6
               Client IP: 127.0.0.1
                     RTT: 64.996µs
       Headers Supported: true
         Maximum Payload: 1.0 MiB
           Connected URL: nats://127.0.0.1:4222
       Connected Address: 127.0.0.1:4222
     Connected Server ID: ND2XVDA4Q363JOIFKJTPZW3ZKZCANH7NJI4EJMFSSPTRXDBFG4M4C34K

JetStream Account Information:

           Memory: 0 B of Unlimited
          Storage: 0 B of Unlimited
          Streams: 0 of Unlimited
        Consumers: 0 of Unlimited 

If you see the below instead then JetStream is not enabled

JetStream Account Information:

   JetStream is not supported in this account

Creating an Object Store bucket

Just like you need to create streams before you can use them you need to first create an Object Store bucket

nats object add myobjbucket

which outputs

myobjbucket Object Store Status

         Bucket Name: myobjbucket
            Replicas: 1
                 TTL: unlimitd
              Sealed: false
                Size: 0 B
  Backing Store Kind: JetStream
    JetStream Stream: OBJ_myobjbucket

Putting a file in the bucket

nats object put myobjbucket ~/Movies/NATS-logo.mov

1.5 GiB / 1.5 GiB [====================================================================================]

Object information for myobjbucket > /Users/jnmoyne/Movies/NATS-logo.mov

               Size: 1.5 GiB
  Modification Time: 14 Apr 22 00:34 +0000
             Chunks: 12,656
             Digest: sha-256 8ee0679dd1462de393d81a3032d71f43d2bc89c0c8a557687cfe2787e926

Listing the objects in a bucket

nats object ls myobjbucket

╭───────────────────────────────────────────────────────────────────────────╮
│                              Bucket Contents                              │
├─────────────────────────────────────┬─────────┬───────────────────────────┤
│ Name                                │ Size    │ Time                      │
├─────────────────────────────────────┼─────────┼───────────────────────────┤
│ /Users/jnmoyne/Movies/NATS-logo.mov │ 1.5 GiB │ 2022-04-13T17:34:55-07:00 │
╰─────────────────────────────────────┴─────────┴───────────────────────────╯

Getting an object from the bucket

nats object get myobjbucket ~/Movies/NATS-logo.mov

1.5 GiB / 1.5 GiB [====================================================================================]

Wrote: 1.5 GiB to /Users/jnmoyne/NATS-logo.mov in 5.68s average 279 MiB/s

Removing an object from the bucket

nats object rm myobjbucket ~/Movies/NATS-logo.mov

? Delete 1.5 GiB byte file myobjbucket > /Users/jnmoyne/Movies/NATS-logo.mov? Yes
Removed myobjbucket > /Users/jnmoyne/Movies/NATS-logo.mov
myobjbucket Object Store Status

         Bucket Name: myobjbucket
            Replicas: 1
                 TTL: unlimitd
              Sealed: false
                Size: 16 MiB
  Backing Store Kind: JetStream
    JetStream Stream: OBJ_myobjbucket

Getting information about the bucket

nats object info myobjbucket

myobjbucket Object Store Status

         Bucket Name: myobjbucket
            Replicas: 1
                 TTL: unlimitd
              Sealed: false
                Size: 1.6 GiB
  Backing Store Kind: JetStream
    JetStream Stream: OBJ_myobjbucket

Watching for changes to a bucket

nats object watch myobjbucket

[2022-04-13 17:51:28] PUT myobjbucket > /Users/jnmoyne/Movies/NATS-logo.mov: 1.5 GiB bytes in 12,656 chunks
[2022-04-13 17:53:27] DEL myobjbucket > /Users/jnmoyne/Movies/NATS-logo.mov

Sealing a bucket

You can seal a bucket, meaning that no further changes are allowed on that bucket

nats object seal myobjbucket

? Really seal Bucket myobjbucket, sealed buckets can not be unsealed or modified Yes
myobjbucket has been sealed
myobjbucket Object Store Status

         Bucket Name: myobjbucket
            Replicas: 1
                 TTL: unlimitd
              Sealed: true
                Size: 1.6 GiB
  Backing Store Kind: JetStream
    JetStream Stream: OBJ_myobjbucket

Deleting a bucket

Using nats object rm myobjbucket will delete the bucket and all the files stored in it.