open-consul/vendor/github.com/hashicorp/go-discover

Go Discover Nodes for Cloud Providers

go-discover is a Go (golang) library and command line tool to discover ip addresses of nodes in cloud environments based on meta information like tags provided by the environment.

The configuration for the providers is provided as a list of key=val key=val ... tuples where the values can be URL encoded. The provider is determined through the provider key. Effectively, only spaces have to be encoded with a + and on the command line you have to observe quoting rules with your shell.

Supported Providers

The following cloud providers have implementations in the go-discover/provider sub packages. Additional providers can be added through the Register function.

• Amazon AWS Config options
• Google Cloud Config options
• Microsoft Azure Config options
• SoftLayer Config options

Config Example

# Amazon AWS
provider=aws region=eu-west-1 tag_key=consul tag_value=... access_key_id=... secret_access_key=...

# Google Cloud
provider=gce project_name=... zone_pattern=eu-west-* tag_value=consul credentials_file=...

# Microsoft Azure
provider=azure tag_name=consul tag_value=... tenant_id=... client_id=... subscription_id=... secret_access_key=...

# SoftLayer
provider=softlayer datacenter=dal06 tag_value=consul username=... api_key=...

Command Line Tool Usage

Install the command line tool with:

go get -u github.com/hashicorp/go-discover/cmd/discover

Then run it with:

$ discover addrs provider=aws region=eu-west-1 ...

Library Usage

Install the library with:

go get -u github.com/hashicorp/go-discover

You can then either support discovery for all available providers or only for some of them.

// support discovery for all supported providers
d := discover.Discover{}

// support discovery for AWS and GCE only
d := discover.Discover{
	Providers : map[string]discover.Provider{
		"aws": discover.Providers["aws"],
		"gce": discover.Providers["gce"],
	}
}

// use ioutil.Discard for no log output
l := log.New(os.Stderr, "", log.LstdFlags)

cfg := "provider=aws region=eu-west-1 ..."
addrs, err := d.Addrs(cfg, l)

For complete API documentation, see GoDoc. The configuration for the supported providers is documented in the providers sub-package.