Allow VM instance security group modification

[falzm]

Fixes #113.

Example usage:

$ ./exo vm show vm1
┼───────────────────────┼──────────────────────────────────────┼
│          VM1          │                                      │
┼───────────────────────┼──────────────────────────────────────┼
│ State                 │ Stopped                              │
│ OS Template           │ Linux Ubuntu 18.04 LTS 64-bit        │
│ Region                │ ch-dk-2                              │
│ Instance Type         │ Tiny                                 │
│ Disk                  │ 10 GB                                │
│ Instance Hostname     │ vm1                                  │
│ Instance Display Name │ vm1                                  │
│ Instance Username     │ ubuntu                               │
│ Created on            │ 2019-03-08T11:25:12+0100             │
│ Base SSH Key          │ default                              │
│ Security Groups       │ default                              │
│ Affinity Groups       │                                      │
│ Instance IP           │ a.b.c.d                              │
│ ID                    │ 1ed46c21-b32d-4359-bd38-d0d149adbe09 │
┼───────────────────────┼──────────────────────────────────────┼

$ ./exo vm firewall add vm1 sg1 sg2
┼─────────────────┼─────────────────────┼
│       VM1       │                     │
┼─────────────────┼─────────────────────┼
│ Security Groups │ default - sg1 - sg2 │
┼─────────────────┼─────────────────────┼

$ ./exo vm firewall remove vm1 sg2
┼─────────────────┼───────────────┼
│       VM1       │               │
┼─────────────────┼───────────────┼
│ Security Groups │ default - sg1 │
┼─────────────────┼───────────────┼

$ ./exo vm firewall set vm1 default
┼─────────────────┼─────────┼
│       VM1       │         │
┼─────────────────┼─────────┼
│ Security Groups │ default │
┼─────────────────┼─────────┼

[falzm]

[ch1475]

Story: Allow VM instance security group modification with exo CLI

[mcorbin]

I have an issue with the remove subcommand. It doesn't seem to work when I try to delete multiple security groups:

$ ./exo vm firewall set debian-build ssh default
┼─────────────────┼───────────────┼
│  DEBIAN-BUILD   │               │
┼─────────────────┼───────────────┼
│ Security Groups │ default - ssh │
┼─────────────────┼───────────────┼

./exo vm firewall remove debian-build ssh default
┼─────────────────┼───────────────┼
│  DEBIAN-BUILD   │               │
┼─────────────────┼───────────────┼
│ Security Groups │ default - ssh │
┼─────────────────┼───────────────┼

./exo vm firewall remove debian-build ssh
┼─────────────────┼─────────┼
│  DEBIAN-BUILD   │         │
┼─────────────────┼─────────┼
│ Security Groups │ default │
┼─────────────────┼─────────┼

[falzm]

I managed to reproduce your issue, however I'm not sure I have a solution for this since it is a consequence of the Go JSON serialization with the omitempty tag: if one removes all the current security groups of an instance, the egoscale.UpdateVirtualMachine.SecurityGroupIDs struct field serializes the empty []egoscale.UUID slice value with omitempty field tag set, which amounts to performing a updateVirtualMachine CloudStack API call without modifying the securitygroupids parameter, hence the instance SG remaining the same as they are currently set.

Maybe @greut has some 🎩 🐇 ✨ for that...

[greut]

thanks @falzm 👍

[greut]

🍯