providers/openstack: initial implementation

this implements getting metadata from the openstack metadata service

src/lib.rs

@@ -96,7 +96,7 @@ pub fn fetch_metadata(provider: &str) -> Result<Metadata> {
         "digitalocean" => digitalocean::fetch_metadata(),
         "ec2" => ec2::fetch_metadata(),
         "gce" => gce::fetch_metadata(),
-        "openstack" => openstack::fetch_metadata(),
+        "openstack-metadata" => openstack::network::fetch_metadata(),
         "oracle-oci" => oracle::fetch_metadata(),
         "packet" => packet::fetch_metadata(),
         "vagrant-virtualbox" => vagrant_virtualbox::fetch_metadata(),

src/providers/openstack/mod.rs

@@ -14,10 +14,4 @@
 
 //! openstack metadata fetcher
 
-use metadata::Metadata;
-
-use errors::*;
-
-pub fn fetch_metadata() -> Result<Metadata> {
-    unimplemented!();
-}
+pub mod network;

src/providers/openstack/network.rs

@@ -0,0 +1,44 @@
+//! openstack metadata fetcher
+
+use errors::*;
+use metadata::Metadata;
+use retry;
+
+const URL: &'static str = "http://169.254.169.254/latest/meta-data";
+
+fn url_for_key(key: &str) -> String {
+    format!("{}/{}", URL, key)
+}
+
+pub fn fetch_metadata() -> Result<Metadata> {
+    let client = retry::Client::new()
+        .chain_err(|| "openstack: failed to create http client")?;
+
+    let hostname: Option<String> = client.get(retry::Raw, url_for_key("hostname")).send()?;
+
+    Ok(Metadata::builder()
+        .add_attribute_if_exists("OPENSTACK_INSTANCE_ID".to_owned(), client.get(retry::Raw, url_for_key("instance-id")).send()?)
+        .add_attribute_if_exists("OPENSTACK_IPV4_LOCAL".to_owned(), client.get(retry::Raw, url_for_key("local-ipv4")).send()?)
+        .add_attribute_if_exists("OPENSTACK_IPV4_PUBLIC".to_owned(), client.get(retry::Raw, url_for_key("public-ipv4")).send()?)
+        .add_attribute_if_exists("OPENSTACK_HOSTNAME".to_owned(), hostname.clone())
+        .set_hostname_if_exists(hostname)
+        .add_ssh_keys(fetch_keys(&client)?)?
+        .build())
+}
+
+fn fetch_keys(client: &retry::Client) -> Result<Vec<String>> {
+    let keys_list: Option<String> = client.get(retry::Raw, url_for_key("public-keys")).send()?;
+    let mut keys = Vec::new();
+    if let Some(keys_list) = keys_list {
+        for l in keys_list.lines() {
+            let tokens: Vec<&str> = l.split('=').collect();
+            if tokens.len() != 2 {
+                return Err("error parsing keyID".into());
+            }
+            let key: String = client.get(retry::Raw, url_for_key(&format!("public-keys/{}/openssh-key", tokens[0]))).send()?
+                .ok_or("missing ssh key")?;
+            keys.push(key);
+        }
+    }
+    Ok(keys)
+}