cloud-detect 3.0.1

//! Google Cloud Platform (GCP).

use std::fs;
use std::path::Path;
use std::sync::mpsc::SyncSender;
use std::time::Duration;

use reqwest::blocking::Client;
use tracing::{debug, error, info, instrument};

use crate::blocking::Provider;
use crate::ProviderId;

const METADATA_URI: &str = "http://metadata.google.internal";
const METADATA_PATH: &str = "/computeMetadata/v1/instance/tags";
const VENDOR_FILE: &str = "/sys/class/dmi/id/product_name";
pub(crate) const IDENTIFIER: ProviderId = ProviderId::GCP;

pub struct Gcp;

impl Provider for Gcp {
    fn identifier(&self) -> ProviderId {
        IDENTIFIER
    }

    /// Tries to identify GCP using all the implemented options.
    #[instrument(skip_all)]
    fn identify(&self, tx: SyncSender<ProviderId>, timeout: Duration) {
        info!("Checking Google Cloud Platform");
        if self.check_vendor_file(VENDOR_FILE) || self.check_metadata_server(METADATA_URI, timeout)
        {
            info!("Identified Google Cloud Platform");
            if let Err(err) = tx.send(IDENTIFIER) {
                error!("Error sending message: {:?}", err);
            }
        }
    }
}

impl Gcp {
    /// Tries to identify GCP via metadata server.
    #[instrument(skip_all)]
    fn check_metadata_server(&self, metadata_uri: &str, timeout: Duration) -> bool {
        let url = format!("{metadata_uri}{METADATA_PATH}");
        debug!("Checking {} metadata using url: {}", IDENTIFIER, url);

        let client = if let Ok(client) = Client::builder().timeout(timeout).build() {
            client
        } else {
            error!("Error creating client");
            return false;
        };

        let req = client.get(url).header("Metadata-Flavor", "Google");
        let resp = req.send();

        match resp {
            Ok(resp) => resp.status().is_success(),
            Err(err) => {
                error!("Error making request: {:?}", err);
                false
            }
        }
    }

    /// Tries to identify GCP using vendor file(s).
    #[instrument(skip_all)]
    fn check_vendor_file<P: AsRef<Path>>(&self, vendor_file: P) -> bool {
        debug!(
            "Checking {} vendor file: {}",
            IDENTIFIER,
            vendor_file.as_ref().display()
        );

        if vendor_file.as_ref().exists() {
            return match fs::read_to_string(vendor_file) {
                Ok(content) => content.contains("Google"),
                Err(err) => {
                    error!("Error reading vendor file: {:?}", err);
                    false
                }
            };
        }

        false
    }
}

#[cfg(test)]
mod tests {
    use std::io::Write;

    use anyhow::Result;
    use mockito::Server;
    use tempfile::NamedTempFile;

    use super::*;

    #[test]
    fn test_check_metadata_server_success() {
        let mut server = Server::new();
        let url = server.url();

        let mock = server.mock("GET", METADATA_PATH).with_status(200).create();

        let provider = Gcp;
        let result = provider.check_metadata_server(&url, Duration::from_secs(1));

        mock.assert();
        assert!(result);
    }

    #[test]
    fn test_check_metadata_server_failure() {
        let mut server = Server::new();
        let url = server.url();

        let mock = server.mock("GET", METADATA_PATH).with_status(500).create();

        let provider = Gcp;
        let result = provider.check_metadata_server(&url, Duration::from_secs(1));

        mock.assert();
        assert!(!result);
    }

    #[test]
    fn test_check_vendor_file_success() -> Result<()> {
        let mut vendor_file = NamedTempFile::new()?;
        vendor_file.write_all(b"Google")?;

        let provider = Gcp;
        let result = provider.check_vendor_file(vendor_file.path());

        assert!(result);

        Ok(())
    }

    #[test]
    fn test_check_vendor_file_failure() -> Result<()> {
        let vendor_file = NamedTempFile::new()?;

        let provider = Gcp;
        let result = provider.check_vendor_file(vendor_file.path());

        assert!(!result);

        Ok(())
    }
}