Files
grafana/pkg/services/apiserver/builder/request_handler.go
T

309 lines
9.5 KiB
Go

package builder
import (
"fmt"
"net/http"
"strings"
"github.com/emicklei/go-restful/v3"
"github.com/gorilla/mux"
"github.com/prometheus/client_golang/prometheus"
serverstorage "k8s.io/apiserver/pkg/server/storage"
klog "k8s.io/klog/v2"
"k8s.io/kube-openapi/pkg/spec3"
)
// convertHandlerToRouteFunction converts an http.HandlerFunc to a restful.RouteFunction
// It extracts path parameters from restful.Request and populates them in the request context
// so that mux.Vars can read them (for backward compatibility with handlers that use mux.Vars)
func convertHandlerToRouteFunction(handler http.HandlerFunc) restful.RouteFunction {
return func(req *restful.Request, resp *restful.Response) {
// Extract path parameters from restful.Request and populate mux.Vars
// This is needed for backward compatibility with handlers that use mux.Vars(r)
vars := make(map[string]string)
// Get all path parameters from the restful.Request
// The restful.Request has PathParameters() method that returns a map
pathParams := req.PathParameters()
for key, value := range pathParams {
vars[key] = value
}
// Set the vars in the request context using mux.SetURLVars
// This makes mux.Vars(r) work correctly
if len(vars) > 0 {
req.Request = mux.SetURLVars(req.Request, vars)
}
handler(resp.ResponseWriter, req.Request)
}
}
// AugmentWebServicesWithCustomRoutes adds custom routes from builders to existing WebServices
// in the container.
func AugmentWebServicesWithCustomRoutes(
container *restful.Container,
builders []APIGroupBuilder,
metricsRegistry prometheus.Registerer,
apiResourceConfig *serverstorage.ResourceConfig,
) error {
if container == nil {
return fmt.Errorf("container cannot be nil")
}
metrics := NewCustomRouteMetrics(metricsRegistry)
// Build a map of existing WebServices by root path
existingWebServices := make(map[string]*restful.WebService)
for _, ws := range container.RegisteredWebServices() {
existingWebServices[ws.RootPath()] = ws
}
for _, b := range builders {
provider, ok := b.(APIGroupRouteProvider)
if !ok || provider == nil {
continue
}
for _, gv := range GetGroupVersions(b) {
// Filter out disabled API groups
gvr := gv.WithResource("")
if apiResourceConfig != nil && !apiResourceConfig.ResourceEnabled(gvr) {
klog.InfoS("Skipping custom routes for disabled group version", "gv", gv.String())
continue
}
routes := provider.GetAPIRoutes(gv)
if routes == nil {
continue
}
// Find or create WebService for this group version
rootPath := "/apis/" + gv.String()
ws, exists := existingWebServices[rootPath]
if !exists {
// Create a new WebService if one doesn't exist
ws = new(restful.WebService)
ws.Path(rootPath)
container.Add(ws)
existingWebServices[rootPath] = ws
}
// Add root handlers using OpenAPI specs
for _, route := range routes.Root {
instrumentedHandler := metrics.InstrumentHandler(
gv.Group,
gv.Version,
route.Path,
route.Handler,
)
routeFunction := convertHandlerToRouteFunction(instrumentedHandler)
// Use OpenAPI spec to configure routes properly
if err := addRouteFromSpec(ws, route.Path, route.Spec, routeFunction, false); err != nil {
return fmt.Errorf("failed to add root route %s: %w", route.Path, err)
}
}
// Add namespace handlers using OpenAPI specs
for _, route := range routes.Namespace {
instrumentedHandler := metrics.InstrumentHandler(
gv.Group,
gv.Version,
route.Path,
route.Handler,
)
routeFunction := convertHandlerToRouteFunction(instrumentedHandler)
// Use OpenAPI spec to configure routes properly
if err := addRouteFromSpec(ws, route.Path, route.Spec, routeFunction, true); err != nil {
return fmt.Errorf("failed to add namespace route %s: %w", route.Path, err)
}
}
}
}
return nil
}
// addRouteFromSpec adds routes to a WebService using OpenAPI specs
func addRouteFromSpec(ws *restful.WebService, routePath string, pathProps *spec3.PathProps, handler restful.RouteFunction, isNamespaced bool) error {
if pathProps == nil {
return fmt.Errorf("pathProps cannot be nil for route %s", routePath)
}
// Build the full path (relative to WebService root)
var fullPath string
if isNamespaced {
fullPath = "/namespaces/{namespace}/" + routePath
} else {
fullPath = "/" + routePath
}
// Add routes for each HTTP method defined in the OpenAPI spec
operations := map[string]*spec3.Operation{
"GET": pathProps.Get,
"POST": pathProps.Post,
"PUT": pathProps.Put,
"PATCH": pathProps.Patch,
"DELETE": pathProps.Delete,
}
for method, operation := range operations {
if operation == nil {
continue
}
// Create route builder for this method
var routeBuilder *restful.RouteBuilder
switch method {
case "GET":
routeBuilder = ws.GET(fullPath)
case "POST":
routeBuilder = ws.POST(fullPath)
case "PUT":
routeBuilder = ws.PUT(fullPath)
case "PATCH":
routeBuilder = ws.PATCH(fullPath)
case "DELETE":
routeBuilder = ws.DELETE(fullPath)
}
// Set operation ID from OpenAPI spec (with K8s verb prefix if needed)
operationID := operation.OperationId
if operationID == "" {
// Generate from path if not specified
operationID = generateOperationNameFromPath(routePath)
}
operationID = prefixRouteIDWithK8sVerbIfNotPresent(operationID, method)
routeBuilder = routeBuilder.Operation(operationID)
// Add description from OpenAPI spec
if operation.Description != "" {
routeBuilder = routeBuilder.Doc(operation.Description)
}
// Check if namespace parameter is already in the OpenAPI spec
hasNamespaceParam := false
if operation.Parameters != nil {
for _, param := range operation.Parameters {
if param.Name == "namespace" && param.In == "path" {
hasNamespaceParam = true
break
}
}
}
// Add namespace parameter for namespaced routes if not already in spec
if isNamespaced && !hasNamespaceParam {
routeBuilder = routeBuilder.Param(restful.PathParameter("namespace", "object name and auth scope, such as for teams and projects"))
}
// Add parameters from OpenAPI spec
if operation.Parameters != nil {
for _, param := range operation.Parameters {
switch param.In {
case "path":
routeBuilder = routeBuilder.Param(restful.PathParameter(param.Name, param.Description))
case "query":
routeBuilder = routeBuilder.Param(restful.QueryParameter(param.Name, param.Description))
case "header":
routeBuilder = routeBuilder.Param(restful.HeaderParameter(param.Name, param.Description))
}
}
}
// Note: Request/response schemas are already defined in the OpenAPI spec from builders
// and will be added to the OpenAPI document via addBuilderRoutes in openapi.go.
// We don't duplicate that information here since restful uses the route metadata
// for OpenAPI generation, which is handled separately in this codebase.
// Register the route with handler
ws.Route(routeBuilder.To(handler))
}
return nil
}
func prefixRouteIDWithK8sVerbIfNotPresent(operationID string, method string) string {
for _, verb := range allowedK8sVerbs {
if len(operationID) > len(verb) && operationID[:len(verb)] == verb {
return operationID
}
}
return fmt.Sprintf("%s%s", httpMethodToK8sVerb[strings.ToUpper(method)], operationID)
}
var allowedK8sVerbs = []string{
"get", "log", "read", "replace", "patch", "delete", "deletecollection", "watch", "connect", "proxy", "list", "create", "patch",
}
var httpMethodToK8sVerb = map[string]string{
http.MethodGet: "get",
http.MethodPost: "create",
http.MethodPut: "replace",
http.MethodPatch: "patch",
http.MethodDelete: "delete",
http.MethodConnect: "connect",
http.MethodOptions: "connect", // No real equivalent to options and head
http.MethodHead: "connect",
}
// generateOperationNameFromPath creates an operation name from a route path.
// The operation name is used by the OpenAPI generator and should be descriptive.
// It uses meaningful path segments to create readable yet unique operation names.
// Examples:
// - "/search" -> "Search"
// - "/snapshots/create" -> "SnapshotsCreate"
// - "ofrep/v1/evaluate/flags" -> "OfrepEvaluateFlags"
// - "ofrep/v1/evaluate/flags/{flagKey}" -> "OfrepEvaluateFlagsFlagKey"
func generateOperationNameFromPath(routePath string) string {
// Remove leading slash and split by path segments
parts := strings.Split(strings.TrimPrefix(routePath, "/"), "/")
// Filter to keep meaningful segments and path parameters
var nameParts []string
skipPrefixes := map[string]bool{
"namespaces": true,
"apis": true,
}
for _, part := range parts {
if part == "" {
continue
}
// Extract parameter name from {paramName} format
if strings.HasPrefix(part, "{") && strings.HasSuffix(part, "}") {
paramName := part[1 : len(part)-1]
// Skip generic parameters like {namespace}, but keep specific ones like {flagKey}
if paramName != "namespace" && paramName != "name" {
nameParts = append(nameParts, strings.ToUpper(paramName[:1])+paramName[1:])
}
continue
}
// Skip common prefixes
if skipPrefixes[strings.ToLower(part)] {
continue
}
// Skip version segments like v1, v0alpha1, v2beta1, etc.
if strings.HasPrefix(strings.ToLower(part), "v") &&
(len(part) <= 3 || strings.Contains(strings.ToLower(part), "alpha") || strings.Contains(strings.ToLower(part), "beta")) {
continue
}
// Capitalize first letter and add to parts
if len(part) > 0 {
nameParts = append(nameParts, strings.ToUpper(part[:1])+part[1:])
}
}
if len(nameParts) == 0 {
return "Route"
}
return strings.Join(nameParts, "")
}