Using the client without a ~/.kube/config file

[azzamsa]

Hi.

Is it possible to create a client without a config ~/.kube/config file?

I develop a micro-service that interacts directly with k8s REST API. It goes well with reqwest, but over time I need to add many structs to access the JSON response. I think using this library will ease the process.

Currently, it looks like this:

        let client = Client::new();
        let resp = client
            .get("http://10.10.10.10:8081/api/v1") // k8s REST API URL
            .basic_auth(username, Some(password))
            .send()
            .await;

In cURL, it looks like this

curl --request GET \
  --url 'http://10.10.10.10:8081/api/v1/namespaces/disney/pods/?labelSelector=pocahontas' \
  --header 'Authorization: Basic secret'

Is it possible to pass only URL, username, and password to the Client in kube::client?

---

For additional perspective, I can avoid using the config file for the AWS S3 client.

    let secret_key = "secret";
    let access_key = "key";
    let url = "https://storage.example.net";

    let cred = aws_sdk_s3::Credentials::new(access_key, secret_key, None, None, "custom");

Thanks in advance! ❤️

[nightkr]

You can create a custom Config, which you can then build a Client from.

If your API gives you a kubeconfig then you can also use Config::from_custom_kubeconfig to load it directly from memory.

[azzamsa]

For searcher who arrived here.

First, you need the kubeconfig. Writing kube::config::Kubeconfig by hand is hard.
In my case, I retrieve the config from its REST API. source

curl -s -X POST -H "Authorization: Bearer <your token>" https://rancher.app.example.net/v3/clusters/<your cluster>?action=generateKubeconfig | jq -r ".config"

Put the configuration in ~/.kube/config and try to use Client::try_default() first to check that the config is valid.

Second, you can use the custom location of the config file using:

    let kube_config = Kubeconfig::read_from("/home/user/playground/rust/src/kube.cfg").unwrap();
    let kube_config_options = KubeConfigOptions {
        context: None,
        cluster: None,
        user: None,
    };
    let config = kube::Config::from_custom_kubeconfig(kube_config, &kube_config_options).await.unwrap();
    let client = Client::try_from(config).unwrap();

Finally, if you don't want to read from a file. Just pretty print the value of kube_config such as:

    let kube_config = Kubeconfig {
        preferences: None,
        clusters: [NamedCluster {
            name: "local".to_string(),
            cluster: Cluster {
                server: "https://rancher.app.example.net/v3/clusters/local"
                    .to_string(),
                insecure_skip_tls_verify: None,
                certificate_authority: None,
                certificate_authority_data: None,
                proxy_url: None,
                extensions: None,
            },
        }]
        .to_vec(),
        auth_infos: [NamedAuthInfo {
            name: "local".to_string(),
            auth_info: AuthInfo {
                username: None,
                password: None,
                token: Some(Secret::new("kubeconfig-user-secret:secret".to_string())),
                token_file: None,
                client_certificate: None,
                client_certificate_data: None,
                client_key: None,
                client_key_data: None,
                impersonate: None,
                impersonate_groups: None,
                auth_provider: None,
                exec: None,
            },
        }]
        .to_vec(),
        contexts: [NamedContext {
            name: "local".to_string(),
            context: Context {
                cluster: "local".to_string(),
                user: "local".to_string(),
                namespace: None,
                extensions: None,
            },
        }]
        .to_vec(),
        current_context: Some("local".to_string()),
        extensions: None,
        kind: Some("Config".to_string()),
        api_version: Some("v1".to_string()),
    };

    let kube_config_options = KubeConfigOptions {
        context: None,
        cluster: None,
        user: None,
    };
    let config = kube::Config::from_custom_kubeconfig(kube_config, &kube_config_options)
        .await
        .unwrap();
    let client = Client::try_from(config).unwrap();

Hope it helps!
Cheers.

Feel free to improve my code.

Thanks a lot @teozkr 🎉

[vCassius]

very nice!