peridot/vendor/github.com/go-openapi/runtime/middleware/router.go
2022-07-07 22:13:21 +02:00

489 lines
14 KiB
Go

// Copyright 2015 go-swagger maintainers
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package middleware
import (
"fmt"
"net/http"
fpath "path"
"regexp"
"strings"
"github.com/go-openapi/runtime/security"
"github.com/go-openapi/swag"
"github.com/go-openapi/analysis"
"github.com/go-openapi/errors"
"github.com/go-openapi/loads"
"github.com/go-openapi/spec"
"github.com/go-openapi/strfmt"
"github.com/go-openapi/runtime"
"github.com/go-openapi/runtime/middleware/denco"
)
// RouteParam is a object to capture route params in a framework agnostic way.
// implementations of the muxer should use these route params to communicate with the
// swagger framework
type RouteParam struct {
Name string
Value string
}
// RouteParams the collection of route params
type RouteParams []RouteParam
// Get gets the value for the route param for the specified key
func (r RouteParams) Get(name string) string {
vv, _, _ := r.GetOK(name)
if len(vv) > 0 {
return vv[len(vv)-1]
}
return ""
}
// GetOK gets the value but also returns booleans to indicate if a key or value
// is present. This aids in validation and satisfies an interface in use there
//
// The returned values are: data, has key, has value
func (r RouteParams) GetOK(name string) ([]string, bool, bool) {
for _, p := range r {
if p.Name == name {
return []string{p.Value}, true, p.Value != ""
}
}
return nil, false, false
}
// NewRouter creates a new context aware router middleware
func NewRouter(ctx *Context, next http.Handler) http.Handler {
if ctx.router == nil {
ctx.router = DefaultRouter(ctx.spec, ctx.api)
}
return http.HandlerFunc(func(rw http.ResponseWriter, r *http.Request) {
if _, rCtx, ok := ctx.RouteInfo(r); ok {
next.ServeHTTP(rw, rCtx)
return
}
// Not found, check if it exists in the other methods first
if others := ctx.AllowedMethods(r); len(others) > 0 {
ctx.Respond(rw, r, ctx.analyzer.RequiredProduces(), nil, errors.MethodNotAllowed(r.Method, others))
return
}
ctx.Respond(rw, r, ctx.analyzer.RequiredProduces(), nil, errors.NotFound("path %s was not found", r.URL.EscapedPath()))
})
}
// RoutableAPI represents an interface for things that can serve
// as a provider of implementations for the swagger router
type RoutableAPI interface {
HandlerFor(string, string) (http.Handler, bool)
ServeErrorFor(string) func(http.ResponseWriter, *http.Request, error)
ConsumersFor([]string) map[string]runtime.Consumer
ProducersFor([]string) map[string]runtime.Producer
AuthenticatorsFor(map[string]spec.SecurityScheme) map[string]runtime.Authenticator
Authorizer() runtime.Authorizer
Formats() strfmt.Registry
DefaultProduces() string
DefaultConsumes() string
}
// Router represents a swagger aware router
type Router interface {
Lookup(method, path string) (*MatchedRoute, bool)
OtherMethods(method, path string) []string
}
type defaultRouteBuilder struct {
spec *loads.Document
analyzer *analysis.Spec
api RoutableAPI
records map[string][]denco.Record
}
type defaultRouter struct {
spec *loads.Document
routers map[string]*denco.Router
}
func newDefaultRouteBuilder(spec *loads.Document, api RoutableAPI) *defaultRouteBuilder {
return &defaultRouteBuilder{
spec: spec,
analyzer: analysis.New(spec.Spec()),
api: api,
records: make(map[string][]denco.Record),
}
}
// DefaultRouter creates a default implemenation of the router
func DefaultRouter(spec *loads.Document, api RoutableAPI) Router {
builder := newDefaultRouteBuilder(spec, api)
if spec != nil {
for method, paths := range builder.analyzer.Operations() {
for path, operation := range paths {
fp := fpath.Join(spec.BasePath(), path)
debugLog("adding route %s %s %q", method, fp, operation.ID)
builder.AddRoute(method, fp, operation)
}
}
}
return builder.Build()
}
// RouteAuthenticator is an authenticator that can compose several authenticators together.
// It also knows when it contains an authenticator that allows for anonymous pass through.
// Contains a group of 1 or more authenticators that have a logical AND relationship
type RouteAuthenticator struct {
Authenticator map[string]runtime.Authenticator
Schemes []string
Scopes map[string][]string
allScopes []string
commonScopes []string
allowAnonymous bool
}
func (ra *RouteAuthenticator) AllowsAnonymous() bool {
return ra.allowAnonymous
}
// AllScopes returns a list of unique scopes that is the combination
// of all the scopes in the requirements
func (ra *RouteAuthenticator) AllScopes() []string {
return ra.allScopes
}
// CommonScopes returns a list of unique scopes that are common in all the
// scopes in the requirements
func (ra *RouteAuthenticator) CommonScopes() []string {
return ra.commonScopes
}
// Authenticate Authenticator interface implementation
func (ra *RouteAuthenticator) Authenticate(req *http.Request, route *MatchedRoute) (bool, interface{}, error) {
if ra.allowAnonymous {
route.Authenticator = ra
return true, nil, nil
}
// iterate in proper order
var lastResult interface{}
for _, scheme := range ra.Schemes {
if authenticator, ok := ra.Authenticator[scheme]; ok {
applies, princ, err := authenticator.Authenticate(&security.ScopedAuthRequest{
Request: req,
RequiredScopes: ra.Scopes[scheme],
})
if !applies {
return false, nil, nil
}
if err != nil {
route.Authenticator = ra
return true, nil, err
}
lastResult = princ
}
}
route.Authenticator = ra
return true, lastResult, nil
}
func stringSliceUnion(slices ...[]string) []string {
unique := make(map[string]struct{})
var result []string
for _, slice := range slices {
for _, entry := range slice {
if _, ok := unique[entry]; ok {
continue
}
unique[entry] = struct{}{}
result = append(result, entry)
}
}
return result
}
func stringSliceIntersection(slices ...[]string) []string {
unique := make(map[string]int)
var intersection []string
total := len(slices)
var emptyCnt int
for _, slice := range slices {
if len(slice) == 0 {
emptyCnt++
continue
}
for _, entry := range slice {
unique[entry]++
if unique[entry] == total-emptyCnt { // this entry appeared in all the non-empty slices
intersection = append(intersection, entry)
}
}
}
return intersection
}
// RouteAuthenticators represents a group of authenticators that represent a logical OR
type RouteAuthenticators []RouteAuthenticator
// AllowsAnonymous returns true when there is an authenticator that means optional auth
func (ras RouteAuthenticators) AllowsAnonymous() bool {
for _, ra := range ras {
if ra.AllowsAnonymous() {
return true
}
}
return false
}
// Authenticate method implemention so this collection can be used as authenticator
func (ras RouteAuthenticators) Authenticate(req *http.Request, route *MatchedRoute) (bool, interface{}, error) {
var lastError error
var allowsAnon bool
var anonAuth RouteAuthenticator
for _, ra := range ras {
if ra.AllowsAnonymous() {
anonAuth = ra
allowsAnon = true
continue
}
applies, usr, err := ra.Authenticate(req, route)
if !applies || err != nil || usr == nil {
if err != nil {
lastError = err
}
continue
}
return applies, usr, nil
}
if allowsAnon && lastError == nil {
route.Authenticator = &anonAuth
return true, nil, lastError
}
return lastError != nil, nil, lastError
}
type routeEntry struct {
PathPattern string
BasePath string
Operation *spec.Operation
Consumes []string
Consumers map[string]runtime.Consumer
Produces []string
Producers map[string]runtime.Producer
Parameters map[string]spec.Parameter
Handler http.Handler
Formats strfmt.Registry
Binder *UntypedRequestBinder
Authenticators RouteAuthenticators
Authorizer runtime.Authorizer
}
// MatchedRoute represents the route that was matched in this request
type MatchedRoute struct {
routeEntry
Params RouteParams
Consumer runtime.Consumer
Producer runtime.Producer
Authenticator *RouteAuthenticator
}
// HasAuth returns true when the route has a security requirement defined
func (m *MatchedRoute) HasAuth() bool {
return len(m.Authenticators) > 0
}
// NeedsAuth returns true when the request still
// needs to perform authentication
func (m *MatchedRoute) NeedsAuth() bool {
return m.HasAuth() && m.Authenticator == nil
}
func (d *defaultRouter) Lookup(method, path string) (*MatchedRoute, bool) {
mth := strings.ToUpper(method)
debugLog("looking up route for %s %s", method, path)
if Debug {
if len(d.routers) == 0 {
debugLog("there are no known routers")
}
for meth := range d.routers {
debugLog("got a router for %s", meth)
}
}
if router, ok := d.routers[mth]; ok {
if m, rp, ok := router.Lookup(fpath.Clean(path)); ok && m != nil {
if entry, ok := m.(*routeEntry); ok {
debugLog("found a route for %s %s with %d parameters", method, path, len(entry.Parameters))
var params RouteParams
for _, p := range rp {
v, err := pathUnescape(p.Value)
if err != nil {
debugLog("failed to escape %q: %v", p.Value, err)
v = p.Value
}
// a workaround to handle fragment/composing parameters until they are supported in denco router
// check if this parameter is a fragment within a path segment
if xpos := strings.Index(entry.PathPattern, fmt.Sprintf("{%s}", p.Name)) + len(p.Name) + 2; xpos < len(entry.PathPattern) && entry.PathPattern[xpos] != '/' {
// extract fragment parameters
ep := strings.Split(entry.PathPattern[xpos:], "/")[0]
pnames, pvalues := decodeCompositParams(p.Name, v, ep, nil, nil)
for i, pname := range pnames {
params = append(params, RouteParam{Name: pname, Value: pvalues[i]})
}
} else {
// use the parameter directly
params = append(params, RouteParam{Name: p.Name, Value: v})
}
}
return &MatchedRoute{routeEntry: *entry, Params: params}, true
}
} else {
debugLog("couldn't find a route by path for %s %s", method, path)
}
} else {
debugLog("couldn't find a route by method for %s %s", method, path)
}
return nil, false
}
func (d *defaultRouter) OtherMethods(method, path string) []string {
mn := strings.ToUpper(method)
var methods []string
for k, v := range d.routers {
if k != mn {
if _, _, ok := v.Lookup(fpath.Clean(path)); ok {
methods = append(methods, k)
continue
}
}
}
return methods
}
// convert swagger parameters per path segment into a denco parameter as multiple parameters per segment are not supported in denco
var pathConverter = regexp.MustCompile(`{(.+?)}([^/]*)`)
func decodeCompositParams(name string, value string, pattern string, names []string, values []string) ([]string, []string) {
pleft := strings.Index(pattern, "{")
names = append(names, name)
if pleft < 0 {
if strings.HasSuffix(value, pattern) {
values = append(values, value[:len(value)-len(pattern)])
} else {
values = append(values, "")
}
} else {
toskip := pattern[:pleft]
pright := strings.Index(pattern, "}")
vright := strings.Index(value, toskip)
if vright >= 0 {
values = append(values, value[:vright])
} else {
values = append(values, "")
value = ""
}
return decodeCompositParams(pattern[pleft+1:pright], value[vright+len(toskip):], pattern[pright+1:], names, values)
}
return names, values
}
func (d *defaultRouteBuilder) AddRoute(method, path string, operation *spec.Operation) {
mn := strings.ToUpper(method)
bp := fpath.Clean(d.spec.BasePath())
if len(bp) > 0 && bp[len(bp)-1] == '/' {
bp = bp[:len(bp)-1]
}
debugLog("operation: %#v", *operation)
if handler, ok := d.api.HandlerFor(method, strings.TrimPrefix(path, bp)); ok {
consumes := d.analyzer.ConsumesFor(operation)
produces := d.analyzer.ProducesFor(operation)
parameters := d.analyzer.ParamsFor(method, strings.TrimPrefix(path, bp))
// add API defaults if not part of the spec
if defConsumes := d.api.DefaultConsumes(); defConsumes != "" && !swag.ContainsStringsCI(consumes, defConsumes) {
consumes = append(consumes, defConsumes)
}
if defProduces := d.api.DefaultProduces(); defProduces != "" && !swag.ContainsStringsCI(produces, defProduces) {
produces = append(produces, defProduces)
}
record := denco.NewRecord(pathConverter.ReplaceAllString(path, ":$1"), &routeEntry{
BasePath: bp,
PathPattern: path,
Operation: operation,
Handler: handler,
Consumes: consumes,
Produces: produces,
Consumers: d.api.ConsumersFor(normalizeOffers(consumes)),
Producers: d.api.ProducersFor(normalizeOffers(produces)),
Parameters: parameters,
Formats: d.api.Formats(),
Binder: NewUntypedRequestBinder(parameters, d.spec.Spec(), d.api.Formats()),
Authenticators: d.buildAuthenticators(operation),
Authorizer: d.api.Authorizer(),
})
d.records[mn] = append(d.records[mn], record)
}
}
func (d *defaultRouteBuilder) buildAuthenticators(operation *spec.Operation) RouteAuthenticators {
requirements := d.analyzer.SecurityRequirementsFor(operation)
var auths []RouteAuthenticator
for _, reqs := range requirements {
var schemes []string
scopes := make(map[string][]string, len(reqs))
var scopeSlices [][]string
for _, req := range reqs {
schemes = append(schemes, req.Name)
scopes[req.Name] = req.Scopes
scopeSlices = append(scopeSlices, req.Scopes)
}
definitions := d.analyzer.SecurityDefinitionsForRequirements(reqs)
authenticators := d.api.AuthenticatorsFor(definitions)
auths = append(auths, RouteAuthenticator{
Authenticator: authenticators,
Schemes: schemes,
Scopes: scopes,
allScopes: stringSliceUnion(scopeSlices...),
commonScopes: stringSliceIntersection(scopeSlices...),
allowAnonymous: len(reqs) == 1 && reqs[0].Name == "",
})
}
return auths
}
func (d *defaultRouteBuilder) Build() *defaultRouter {
routers := make(map[string]*denco.Router)
for method, records := range d.records {
router := denco.New()
_ = router.Build(records)
routers[method] = router
}
return &defaultRouter{
spec: d.spec,
routers: routers,
}
}