portainer/api/http/handler/stacks/stack_file.go

package stacks

import (
	"net/http"
	"path"

	httperror "github.com/portainer/libhttp/error"
	"github.com/portainer/libhttp/request"
	"github.com/portainer/libhttp/response"
	"github.com/portainer/portainer/api"
	"github.com/portainer/portainer/api/http/security"
)

type stackFileResponse struct {
	StackFileContent string `json:"StackFileContent"`
}

// GET request on /api/stacks/:id/file
func (handler *Handler) stackFile(w http.ResponseWriter, r *http.Request) *httperror.HandlerError {
	stackID, err := request.RetrieveNumericRouteVariableValue(r, "id")
	if err != nil {
		return &httperror.HandlerError{http.StatusBadRequest, "Invalid stack identifier route variable", err}
	}

	stack, err := handler.StackService.Stack(portainer.StackID(stackID))
	if err == portainer.ErrObjectNotFound {
		return &httperror.HandlerError{http.StatusNotFound, "Unable to find a stack with the specified identifier inside the database", err}
	} else if err != nil {
		return &httperror.HandlerError{http.StatusInternalServerError, "Unable to find a stack with the specified identifier inside the database", err}
	}

	endpoint, err := handler.EndpointService.Endpoint(stack.EndpointID)
	if err == portainer.ErrObjectNotFound {
		return &httperror.HandlerError{http.StatusNotFound, "Unable to find an endpoint with the specified identifier inside the database", err}
	} else if err != nil {
		return &httperror.HandlerError{http.StatusInternalServerError, "Unable to find an endpoint with the specified identifier inside the database", err}
	}

	err = handler.requestBouncer.AuthorizedEndpointOperation(r, endpoint, true)
	if err != nil {
		return &httperror.HandlerError{http.StatusForbidden, "Permission denied to access endpoint", err}
	}

	resourceControl, err := handler.ResourceControlService.ResourceControlByResourceIDAndType(stack.Name, portainer.StackResourceControl)
	if err != nil {
		return &httperror.HandlerError{http.StatusInternalServerError, "Unable to retrieve a resource control associated to the stack", err}
	}

	securityContext, err := security.RetrieveRestrictedRequestContext(r)
	if err != nil {
		return &httperror.HandlerError{http.StatusInternalServerError, "Unable to retrieve info from request context", err}
	}

	access, err := handler.userCanAccessStack(securityContext, endpoint.ID, resourceControl)
	if err != nil {
		return &httperror.HandlerError{http.StatusInternalServerError, "Unable to verify user authorizations to validate stack access", err}
	}
	if !access {
		return &httperror.HandlerError{http.StatusForbidden, "Access denied to resource", portainer.ErrResourceAccessDenied}
	}

	stackFileContent, err := handler.FileService.GetFileContent(path.Join(stack.ProjectPath, stack.EntryPoint))
	if err != nil {
		return &httperror.HandlerError{http.StatusInternalServerError, "Unable to retrieve Compose file from disk", err}
	}

	return response.JSON(w, &stackFileResponse{StackFileContent: string(stackFileContent)})
}