Add a new cloud provider

This section explains how to add a new cloud provider to KubeSkoop diagnose.

Implement InfraShim

InfraShim is used for checking configuration of the underlying infra network.

type InfraShim interface {
    NodeToNode(src *v1.Node, oif string, dst *v1.Node, packet *model.Packet) ([]model.Suspicion, error)
    NodeToExternal(src *v1.Node, oif string, packet *model.Packet) ([]model.Suspicion, error)
}

• NodeToNode(): Transmission between two nodes. Accepts kubernetes *v1.Node for source and destination, output interface name, and *model.Packet. Returns []model.Suspicions as result.

• NodeToExternal() : Transmission from node to external network (eg. internet). Accepts kubernetes *v1.Node for source, output interface name and *model.Packet. Returns []model.Suspicions as result.

InfraShim is responsible to check whether the packet can reach its destination in the underlying network, for example, an address in intranet but outside of the cluster should check routes and security groups rules, or an address in internet should check NAT entries.

InfraShim should be implemented in pkg/skoop/network/<provider name>.

Implement Network

Network are also located in pkg/skoop/network/<provider name>.They are both cloud provider specified and plugin specified, so you should implement your own Network for supported plugins.

type Network interface {
    Diagnose(ctx *ctx.Context, src model.Endpoint, dst model.Endpoint) ([]model.Suspicion, *model.PacketPath, error)
}

• Diagnose(): accepts *ctx.Context, source and destination as *model.Endpoint. Returns []model.Suspicion and *model.PacketPath.

A Network should configure all resources that a diagnosis progress needs, including Plugin, Diagnostor, InfraShim, etc.

Add new Provider

Provider are located in pkg/skoop/provider.

type Provider interface {
    CreateNetwork(ctx *ctx.Context) (network.Network, error)
}

• CreateNetwork(): accepts *ctx.Context and returns network.Network.

The implementation of Provider is simple: check the plugin type, and create corresponding Network.

type genericProvider struct {
}

func (g genericProvider) CreateNetwork(ctx *context.Context) (network.Network, error) {
    switch ctx.ClusterConfig().NetworkPlugin {
    case context.NetworkPluginFlannel:
        return generic.NewFlannelNetwork(ctx)
    case context.NetworkPluginCalico:
        return generic.NewCalicoNetwork(ctx)
    default:
        return nil, fmt.Errorf("not support cni type %q", ctx.ClusterConfig().NetworkPlugin)
    }
}

You should implement your Provider in pkg/skoop/provider/<provider name>.go.

Then, a new provider type constant need to be added in pkg/skoop/provider/provider.go.

const (
    providerNameGeneric = "generic"
    providerNameAliyun  = "aliyun"
    // add new provider name here
)

This constant value will be used in the command line arguments

At last, add your implementation to providers.

var providers = map[string]Provider{
    providerNameGeneric: genericProvider{},
    providerNameAliyun:  aliyunProvider{},
    // add new provider
}

Components used by cloud providers

Cloud provider related components are located in pkg/skoop/infra/<provider name>. Such as config, or cloud client.

If you want to add any flags for your plugin, you should implement ConfigBinder, and register it. For example in pkg/skoop/infra/aliyun/config.go.

type ProviderConfig struct {
    AccessKeyID     string
    AccessKeySecret string
    SecurityToken   string
}

var Config = &ProviderConfig{}

func init() {
    context.RegisterConfigBinder("Aliyun provider", Config)
}

func (pc *ProviderConfig) BindFlags(fs *pflag.FlagSet) {
    fs.StringVarP(&pc.AccessKeyID, "aliyun-access-key-id", "", "", "Aliyun access key.")
    fs.StringVarP(&pc.AccessKeySecret, "aliyun-access-key-secret", "", "", "Aliyun access secret.")
    fs.StringVarP(&pc.SecurityToken, "aliyun-security-token", "", "", "Aliyun security token (optional).")
}

func (pc *ProviderConfig) Validate() error {
    return nil
}