portainer/portainer

package endpointproxy

import (
    "errors"
    "fmt"
    "net/http"
    "strings"

    portainer "github.com/portainer/portainer/api"
    httperror "github.com/portainer/portainer/pkg/libhttp/error"
    "github.com/portainer/portainer/pkg/libhttp/request"
)

func (handler *Handler) proxyRequestsToKubernetesAPI(w http.ResponseWriter, r *http.Request) *httperror.HandlerError {
    endpointID, err := request.RetrieveNumericRouteVariableValue(r, "id")
    if err != nil {
        return httperror.BadRequest("Invalid environment identifier route variable", err)
    }

    endpoint, err := handler.DataStore.Endpoint().Endpoint(portainer.EndpointID(endpointID))
    if handler.DataStore.IsErrObjectNotFound(err) {
        return httperror.NotFound("Unable to find an environment with the specified identifier inside the database", err)
    } else if err != nil {
        return httperror.InternalServerError("Unable to find an environment with the specified identifier inside the database", err)
    }

    err = handler.requestBouncer.AuthorizedEndpointOperation(r, endpoint)
    if err != nil {
        return httperror.Forbidden("Permission denied to access environment", err)
    }

    if endpoint.Type == portainer.EdgeAgentOnKubernetesEnvironment {
        if endpoint.EdgeID == "" {
            return httperror.InternalServerError("No Edge agent registered with the environment", errors.New("No agent available"))
        }

        _, err := handler.ReverseTunnelService.GetActiveTunnel(endpoint)
        if err != nil {
            return httperror.InternalServerError("Unable to get the active tunnel", err)
        }
    }

    var proxy http.Handler
    proxy = handler.ProxyManager.GetEndpointProxy(endpoint)
    if proxy == nil {
        proxy, err = handler.ProxyManager.CreateAndRegisterEndpointProxy(endpoint)
        if err != nil {
            return httperror.InternalServerError("Unable to create proxy", err)
        }
    }

    //  For KubernetesLocalEnvironment
    requestPrefix := fmt.Sprintf("/%d/kubernetes", endpointID)

    if endpoint.Type == portainer.AgentOnKubernetesEnvironment || endpoint.Type == portainer.EdgeAgentOnKubernetesEnvironment {
        requestPrefix = fmt.Sprintf("/%d", endpointID)

        agentPrefix := fmt.Sprintf("/%d/agent/kubernetes", endpointID)
        if strings.HasPrefix(r.URL.Path, agentPrefix) {
            requestPrefix = agentPrefix
        }
    }

    http.StripPrefix(requestPrefix, proxy).ServeHTTP(w, r)
    return nil
}