Add PowerVS provider

As part of supporting Power Virtual server as a platform (coreos/fedora-coreos-tracker#817), Afterburn will be used to set the hostname attributes and possibly the ssh-keys.

This provider is very similar to the IBMCloud classic provider with the exception of the filesystem for the config drive which is `iso9660` similar to Openstack. The contents of the config drive are usually the meta_data.json and the network_data.json. This provider includes support for:
- hostname
- ssh keys

docs/platforms.md

@@ -51,6 +51,9 @@ The following platforms are supported, with a different set of features availabl
   - Attributes
   - First-boot check-in
   - SSH Keys
+* powervs
+  - Attributes
+  - SSH keys
 * vmware
   - Custom network command-line arguments
 * vultr

docs/usage/attributes.md

@@ -105,6 +105,9 @@ Cloud providers with supported metadata endpoints and their respective attribute
   - AFTERBURN_PACKET_IPV4_PRIVATE_GATEWAY_0
   - AFTERBURN_PACKET_IPV6_PUBLIC_0
   - AFTERBURN_PACKET_IPV6_PUBLIC_GATEWAY_0
+* powervs
+  - AFTERBURN_POWERVS_INSTANCE_ID
+  - AFTERBURN_POWERVS_LOCAL_HOSTNAME
 * vultr
   - AFTERBURN_VULTR_HOSTNAME
   - AFTERBURN_VULTR_INSTANCE_ID

src/metadata.rs

@@ -29,6 +29,7 @@ use crate::providers::microsoft::azurestack::AzureStack;
 use crate::providers::openstack;
 use crate::providers::openstack::network::OpenstackProviderNetwork;
 use crate::providers::packet::PacketProvider;
+use crate::providers::powervs::PowerVSProvider;
 use crate::providers::vmware::VmwareProvider;
 use crate::providers::vultr::VultrProvider;
 
@@ -61,6 +62,7 @@ pub fn fetch_metadata(provider: &str) -> Result<Box<dyn providers::MetadataProvi
         "openstack" => openstack::try_config_drive_else_network(),
         "openstack-metadata" => box_result!(OpenstackProviderNetwork::try_new()?),
         "packet" => box_result!(PacketProvider::try_new()?),
+        "powervs" => box_result!(PowerVSProvider::try_new()?),
         "vmware" => box_result!(VmwareProvider::try_new()?),
         "vultr" => box_result!(VultrProvider::try_new()?),
         _ => bail!("unknown provider '{}'", provider),

src/providers/mod.rs

@@ -34,6 +34,7 @@ pub mod ibmcloud_classic;
 pub mod microsoft;
 pub mod openstack;
 pub mod packet;
+pub mod powervs;
 pub mod vmware;
 pub mod vultr;
 

src/providers/powervs/mod.rs

@@ -0,0 +1,239 @@
+//! Metadata fetcher for PowerVS instances.
+//!
+//! This provider supports the Power Virtual Server infrastructure type on IBMCloud.
+//! It provides a config-drive as the only metadata source, whose layout
+//! follows the `cloud-init ConfigDrive v2` [datasource][configdrive], with
+//! the following details:
+//!  - disk filesystem label is `config-2` (lowercase)
+//!  - filesystem is `iso9660`
+//!  - drive contains a single directory at `/openstack/latest/`
+//!  - content is exposed as JSON files called `meta_data.json`.
+//!
+//! configdrive: https://cloudinit.readthedocs.io/en/latest/topics/datasources/configdrive.html
+
+use anyhow::{bail, Context, Result};
+use openssh_keys::PublicKey;
+use serde::Deserialize;
+use slog_scope::warn;
+use std::collections::HashMap;
+use std::fs::File;
+use std::io::{BufReader, Read};
+use std::path::{Path, PathBuf};
+use tempfile::TempDir;
+
+use crate::network;
+use crate::providers::MetadataProvider;
+
+// Filesystem label for the Config Drive.
+static CONFIG_DRIVE_FS_LABEL: &str = "config-2";
+
+// Filesystem type for the Config Drive.
+static CONFIG_DRIVE_FS_TYPE: &str = "iso9660";
+
+///PowerVS provider.
+#[derive(Debug)]
+pub struct PowerVSProvider {
+    /// Path to the top directory of the mounted config-drive.
+    drive_path: PathBuf,
+    /// Temporary directory for own mountpoint.
+    temp_dir: TempDir,
+}
+
+/// Partial object for `meta_data.json`
+#[derive(Debug, Deserialize)]
+pub struct MetaDataJSON {
+    /// Fully-Qualified Domain Name (FQDN).
+    #[serde(rename = "hostname")]
+    pub fqdn: String,
+    /// Local hostname.
+    #[serde(rename = "name")]
+    pub local_hostname: String,
+    /// Instance ID (UUID).
+    #[serde(rename = "uuid")]
+    pub instance_id: String,
+    /// SSH public keys.
+    pub public_keys: Option<HashMap<String, String>>,
+}
+
+impl PowerVSProvider {
+    /// Try to build a new provider client.
+    ///
+    /// This internally tries to mount (and own) the config-drive.
+    pub fn try_new() -> Result<Self> {
+        let target = tempfile::Builder::new()
+            .prefix("afterburn-")
+            .tempdir()
+            .context("failed to create temporary directory")?;
+        crate::util::mount_ro(
+            &Path::new("/dev/disk/by-label/").join(CONFIG_DRIVE_FS_LABEL),
+            target.path(),
+            CONFIG_DRIVE_FS_TYPE,
+            3, // maximum retries
+        )?;
+
+        let provider = Self {
+            drive_path: target.path().to_owned(),
+            temp_dir: target,
+        };
+        Ok(provider)
+    }
+
+    /// Return the path to the metadata directory.
+    fn metadata_dir(&self) -> PathBuf {
+        let drive = self.drive_path.clone();
+        drive.join("openstack").join("latest")
+    }
+
+    /// Read and parse metadata file.
+    fn read_metadata(&self) -> Result<MetaDataJSON> {
+        let filename = self.metadata_dir().join("meta_data.json");
+        let file = File::open(&filename)
+            .with_context(|| format!("failed to open file '{:?}'", filename))?;
+        let bufrd = BufReader::new(file);
+        Self::parse_metadata(bufrd)
+    }
+
+    /// Parse metadata attributes.
+    ///
+    /// Metadata file contains a JSON object, corresponding to `MetaDataJSON`.
+    fn parse_metadata<T: Read>(input: BufReader<T>) -> Result<MetaDataJSON> {
+        serde_json::from_reader(input).context("failed to parse JSON metadata")
+    }
+
+    /// Extract supported metadata values and convert to Afterburn attributes.
+    ///
+    /// The `AFTERBURN_` prefix is added later on, so it is not part of the
+    /// key-labels here.
+    fn known_attributes(metadata: MetaDataJSON) -> Result<HashMap<String, String>> {
+        if metadata.instance_id.is_empty() {
+            bail!("empty instance ID");
+        }
+
+        if metadata.local_hostname.is_empty() {
+            bail!("empty local hostname");
+        }
+
+        let attrs = maplit::hashmap! {
+            "POWERVS_INSTANCE_ID".to_string() => metadata.instance_id,
+            "POWERVS_LOCAL_HOSTNAME".to_string() => metadata.local_hostname,
+
+        };
+        Ok(attrs)
+    }
+
+    /// The public key is stored as key:value pair in openstack/latest/meta_data.json file
+    fn public_keys(metadata: MetaDataJSON) -> Result<Vec<PublicKey>> {
+        let public_keys_map = metadata.public_keys.unwrap_or_default();
+        let public_keys_vec: Vec<&std::string::String> = public_keys_map.values().collect();
+        let mut out = vec![];
+        for key in public_keys_vec {
+            let key = PublicKey::parse(key)?;
+            out.push(key);
+        }
+        Ok(out)
+    }
+}
+
+impl MetadataProvider for PowerVSProvider {
+    fn attributes(&self) -> Result<HashMap<String, String>> {
+        let metadata = self.read_metadata()?;
+        Self::known_attributes(metadata)
+    }
+
+    fn hostname(&self) -> Result<Option<String>> {
+        let metadata = self.read_metadata()?;
+        let hostname = if metadata.local_hostname.is_empty() {
+            None
+        } else {
+            Some(metadata.local_hostname)
+        };
+        Ok(hostname)
+    }
+
+    fn ssh_keys(&self) -> Result<Vec<PublicKey>> {
+        let metadata = self.read_metadata()?;
+        Self::public_keys(metadata)
+    }
+
+    fn networks(&self) -> Result<Vec<network::Interface>> {
+        warn!("network interfaces metadata requested, but not supported on this platform");
+        Ok(vec![])
+    }
+
+    fn virtual_network_devices(&self) -> Result<Vec<network::VirtualNetDev>> {
+        warn!("virtual network devices metadata requested, but not supported on this platform");
+        Ok(vec![])
+    }
+
+    fn boot_checkin(&self) -> Result<()> {
+        warn!("boot check-in requested, but not supported on this platform");
+        Ok(())
+    }
+}
+
+impl Drop for PowerVSProvider {
+    fn drop(&mut self) {
+        if let Err(e) = crate::util::unmount(
+            self.temp_dir.path(),
+            3, // maximum retries
+        ) {
+            slog_scope::error!("failed to unmount powervs config-drive: {}", e);
+        };
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use std::io::Cursor;
+
+    #[test]
+    fn test_powervs_basic_attributes() {
+        let metadata = r#"
+{
+  "hostname": "test_instance-powervs.foo.cloud",
+  "name": "test_instance-powervs",
+  "uuid": "41b4fb82-ca29-11eb-b8bc-0242ac130003"
+}
+"#;
+
+        let bufrd = BufReader::new(Cursor::new(metadata));
+        let parsed = PowerVSProvider::parse_metadata(bufrd).unwrap();
+        assert_eq!(parsed.instance_id, "41b4fb82-ca29-11eb-b8bc-0242ac130003",);
+        assert_eq!(parsed.local_hostname, "test_instance-powervs",);
+
+        let attrs = PowerVSProvider::known_attributes(parsed).unwrap();
+        assert_eq!(attrs.len(), 2);
+        assert_eq!(
+            attrs.get("POWERVS_INSTANCE_ID"),
+            Some(&"41b4fb82-ca29-11eb-b8bc-0242ac130003".to_string())
+        );
+        assert_eq!(
+            attrs.get("POWERVS_LOCAL_HOSTNAME"),
+            Some(&"test_instance-powervs".to_string())
+        );
+    }
+
+    #[test]
+    fn test_powervs_parse_metadata_json() {
+        let fixture = File::open("./tests/fixtures/powervs/meta_data.json").unwrap();
+        let bufrd = BufReader::new(fixture);
+        let parsed = PowerVSProvider::parse_metadata(bufrd).unwrap();
+
+        assert!(!parsed.instance_id.is_empty());
+        assert!(!parsed.local_hostname.is_empty());
+        assert!(!parsed.public_keys.is_none());
+    }
+
+    #[test]
+    fn test_powervs_ssh_keys() {
+        let fixture = File::open("./tests/fixtures/powervs/meta_data.json").unwrap();
+        let bufrd = BufReader::new(fixture);
+        let parsed = PowerVSProvider::parse_metadata(bufrd).unwrap();
+        let keys = PowerVSProvider::public_keys(parsed).unwrap();
+        let expect = PublicKey::parse("ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQDmMuiypdqqftqhrQeBTjOhcgyARvylZMLiH+6nCvi5Lv5M7evAnvvG3Hz4rbjbbqoVgSCIdAEb4PuttiCdwE6UyAl0TYAydOVPx7l87BlaucTEqDFbXkQB+yyUmzodllCpWAMUmxwvJB/ntFrC6rP0K0kKxx4SESvozutwM2X5oH3LNHcYI1xgKIMF9VMJLkkM0rLo8Fmj6mWF5KtbU7vS7JJPvLTCRhW5TYrqvhHKuIS6KBtj3GJqvRt+it8AsIb6/RUaji68Mt7W41UrmFSPt8bxJMdE/xKGMcFQjamURPSCHx7z8/pr2/pv2QbQF76FO7lRdPH3f542uAkOOpO1 user1@user1-MacBook-Pro-2.local").unwrap();
+
+        assert_eq!(keys.len(), 1);
+        assert_eq!(keys[0], expect);
+    }
+}

tests/fixtures/powervs/meta_data.json

@@ -0,0 +1,32 @@
+{
+    "admin_pass": "oSfw8JEKHvBo",
+    "random_seed": "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",
+    "uuid": "1c0c0bb6-8dcd-4966-ad80-946b871814f1",
+    "availability_zone": "s922",
+    "keys": [
+      {
+        "data": "ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQDmMuiypdqqftqhrQeBTjOhcgyARvylZMLiH+6nCvi5Lv5M7evAnvvG3Hz4rbjbbqoVgSCIdAEb4PuttiCdwE6UyAl0TYAydOVPx7l87BlaucTEqDFbXkQB+yyUmzodllCpWAMUmxwvJB/ntFrC6rP0K0kKxx4SESvozutwM2X5oH3LNHcYI1xgKIMF9VMJLkkM0rLo8Fmj6mWF5KtbU7vS7JJPvLTCRhW5TYrqvhHKuIS6KBtj3GJqvRt+it8AsIb6/RUaji68Mt7W41UrmFSPt8bxJMdE/xKGMcFQjamURPSCHx7z8/pr2/pv2QbQF76FO7lRdPH3f542uAkOOpO1 user1@user1-MacBook-Pro-2.local",
+        "type": "ssh",
+        "name": "65b64c1f1c29460e8c2e4bbfbd893c2c_7c6cd5d4-a7aa-4d07-bb89-94f274bfeed0_user1-pub-key"
+      }
+    ],
+    "hostname": "test-tf-pvm.power-iaas.cloud.ibm.com",
+    "launch_index": 0,
+    "devices": [],
+    "meta": {
+      "ibmiDBQ": "false",
+      "ibmiCSS": "false",
+      "storage_pool": "Tier1-Flash-2",
+      "ibmiRDS": "false",
+      "ibmiPHA": "false"
+    },
+    "public_keys": {
+      "65b64c1f1c29460e8c2e4bbfbd893c2c_7c6cd5d4-a7aa-4d07-bb89-94f274bfeed0_user1-pub-key": "ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQDmMuiypdqqftqhrQeBTjOhcgyARvylZMLiH+6nCvi5Lv5M7evAnvvG3Hz4rbjbbqoVgSCIdAEb4PuttiCdwE6UyAl0TYAydOVPx7l87BlaucTEqDFbXkQB+yyUmzodllCpWAMUmxwvJB/ntFrC6rP0K0kKxx4SESvozutwM2X5oH3LNHcYI1xgKIMF9VMJLkkM0rLo8Fmj6mWF5KtbU7vS7JJPvLTCRhW5TYrqvhHKuIS6KBtj3GJqvRt+it8AsIb6/RUaji68Mt7W41UrmFSPt8bxJMdE/xKGMcFQjamURPSCHx7z8/pr2/pv2QbQF76FO7lRdPH3f542uAkOOpO1 user1@user1-MacBook-Pro-2.local"
+    },
+    "project_id": "15ea5428420d4d47be42e19332645a18",
+    "network_config": {
+      "content_path": "/content/0000",
+      "name": "network_config"
+    },
+    "name": "test-tf-pVM"
+  }