triton_network: Add data source for triton_networks

[jwreagor]

This adds a new data source for pulling up network UUIDs by their name/label. Here's two examples of looking up Joyent-SDC-Public and Joyent-SDC-Private. Any caps sensitive string part of the network name will match. The first match is used.

data "triton_network" "private" {
  name = "SDC-Private"
}

data "triton_network" "public" {
  name = "SDC-Public"
}

resource "triton_machine" "tf-base" {
  name = "tf-base-${count.index}"
  package = "g4-highcpu-512M"
  image = "${data.triton_image.base.id}"

  nic {
    network = "${data.triton_network.public.id}"
  }

  tags {
    version = "1.0.0"
    role = "test"
  }
}

/cc @jen20 @sean-

[sean-]

Looks good.

1. Docs?
2. How does this handle network pools?

[sean-]

strings.Contains() vs a strict == comparison?

[jwreagor]

This was providing a feature to search but, in hindsight, probably should be a direct one-to-one comparison. I'll change this.

[jen20]

I would use a direct comparison here and require the full name. It might also be worth adding a switch for whether the network is a fabric?

[jwreagor]

@jen20 It's sort of bunk that the ListNetworks endpoint of CloudAPI doesn't provide any filter or search capabilities. Neither do many other List endpoints for that matter (can I haz cloudapi-go). But I can certainly add this (or any other returned field) since the implementation pulls all networks.

[jwreagor]

How does this handle network pools?

This should be the existing behavior as the data source simply maps the network name to it's UUID.

[jen20]

I think with respect to network pools we'll need to make upstream API changes, since it's effectively impossible to converge on a given network if there are multiple pools involved.

[jwreagor]

I've updated according to what we last spoke about. Curious what filters everyone might want, I can certainly add more.

[jen20]

Couple of minor nits here - I think to make this substantially more useful we should also expose the address space.

[jen20]

s/it's name/the name of the network/ ?

[jen20]

This probably wants an "Attribute Reference" section too. We probably want to expose the address space as well as the network, in order that it can be used as input into the various IP functions.

[jen20]

I rebased and fixed this up, merged it as ea8ad1f. Thanks @cheapRoc!

[jen20]

We can add other attributes at a future point.