Initial QSfera import

Server/services/proxy/pkg/proxy/option.go

@@ -0,0 +1,40 @@
+package proxy
+
+import (
+	"github.com/qsfera/server/pkg/log"
+	"github.com/qsfera/server/services/proxy/pkg/config"
+)
+
+// Option defines a single option function.
+type Option func(o *Options)
+
+// Options defines the available options for this package.
+type Options struct {
+	Logger log.Logger
+	Config *config.Config
+}
+
+// newOptions initializes the available default options.
+func newOptions(opts ...Option) Options {
+	opt := Options{}
+
+	for _, o := range opts {
+		o(&opt)
+	}
+
+	return opt
+}
+
+// Logger provides a function to set the logger option.
+func Logger(val log.Logger) Option {
+	return func(o *Options) {
+		o.Logger = val
+	}
+}
+
+// Config provides a function to set the config option.
+func Config(val *config.Config) Option {
+	return func(o *Options) {
+		o.Config = val
+	}
+}

Server/services/proxy/pkg/proxy/policy/selector.go

@@ -0,0 +1,223 @@
+package policy
+
+import (
+	"fmt"
+	"net/http"
+	"regexp"
+	"sort"
+
+	"github.com/qsfera/server/pkg/oidc"
+	"github.com/qsfera/server/services/proxy/pkg/config"
+	revactx "github.com/opencloud-eu/reva/v2/pkg/ctx"
+)
+
+var (
+	// ErrMultipleSelectors in case there is more then one selector configured.
+	ErrMultipleSelectors = fmt.Errorf("only one type of policy-selector (static, migration, claim or regex) can be configured")
+	// ErrSelectorConfigIncomplete if policy_selector conf is missing
+	ErrSelectorConfigIncomplete = fmt.Errorf("missing either \"static\", \"migration\", \"claim\" or \"regex\" configuration in policy_selector config ")
+	// ErrUnexpectedConfigError unexpected config error
+	ErrUnexpectedConfigError = fmt.Errorf("could not initialize policy-selector for given config")
+)
+
+const (
+	SelectorCookieName = "qsfera-selector"
+)
+
+// Selector is a function which selects a proxy-policy based on the request.
+//
+// A policy is a random name which identifies a set of proxy-routes:
+//
+//	{
+//	 "policies": [
+//	   {
+//	     "name": "us-east-1",
+//	     "routes": [
+//	       {
+//	         "endpoint": "/",
+//	         "backend": "https://backend.us.example.com:8080/app"
+//	       }
+//	     ]
+//	   },
+//	   {
+//	     "name": "eu-ams-1",
+//	     "routes": [
+//	       {
+//	         "endpoint": "/",
+//	         "backend": "https://backend.eu.example.com:8080/app"
+//	       }
+//	     ]
+//	   }
+//	 ]
+//	}
+type Selector func(r *http.Request) (string, error)
+
+// LoadSelector constructs a specific policy-selector from a given configuration
+func LoadSelector(cfg *config.PolicySelector) (Selector, error) {
+	selCount := 0
+
+	if cfg.Static != nil {
+		selCount++
+	}
+	if cfg.Claims != nil {
+		selCount++
+	}
+	if cfg.Regex != nil {
+		selCount++
+	}
+	if selCount > 1 {
+		return nil, ErrMultipleSelectors
+	}
+
+	if cfg.Static == nil && cfg.Claims == nil && cfg.Regex == nil {
+		return nil, ErrSelectorConfigIncomplete
+	}
+
+	if cfg.Static != nil {
+		return NewStaticSelector(cfg.Static), nil
+	}
+
+	if cfg.Claims != nil {
+		if cfg.Claims.SelectorCookieName == "" {
+			cfg.Claims.SelectorCookieName = SelectorCookieName
+		}
+		return NewClaimsSelector(cfg.Claims), nil
+	}
+
+	if cfg.Regex != nil {
+		if cfg.Regex.SelectorCookieName == "" {
+			cfg.Regex.SelectorCookieName = SelectorCookieName
+		}
+		return NewRegexSelector(cfg.Regex), nil
+	}
+
+	return nil, ErrUnexpectedConfigError
+}
+
+// NewStaticSelector returns a selector which uses a pre-configured policy.
+//
+// Configuration:
+//
+//	"policy_selector": {
+//	   "static": {"policy" : "qsfera"}
+//	 },
+func NewStaticSelector(cfg *config.StaticSelectorConf) Selector {
+	return func(r *http.Request) (s string, err error) {
+		return cfg.Policy, nil
+	}
+}
+
+// NewClaimsSelector selects the policy based on the "qsfera.routing.policy" claim
+// The policy for corner cases is configurable:
+//
+//	"policy_selector": {
+//	   "migration": {
+//	     "default_policy" : "qsfera",
+//	     "unauthenticated_policy": "oc10"
+//	   }
+//	 },
+//
+// This selector can be used in migration-scenarios or to set up sharded deployments
+func NewClaimsSelector(cfg *config.ClaimsSelectorConf) Selector {
+	return func(r *http.Request) (s string, err error) {
+
+		selectorCookie := func(r *http.Request) string {
+			selectorCookie, err := r.Cookie(cfg.SelectorCookieName)
+			if err == nil {
+				// TODO check we know the routing policy?
+				return selectorCookie.Value
+			}
+			return ""
+		}
+
+		// first, try to route by selector
+		if claims := oidc.FromContext(r.Context()); claims != nil {
+			if p, ok := claims[oidc.QsferaRoutingPolicy].(string); ok && p != "" {
+				// TODO check we know the routing policy?
+				return p, nil
+			}
+
+			// basic auth requests don't have a routing claim, so check for the cookie
+			if s := selectorCookie(r); s != "" {
+				return s, nil
+			}
+
+			return cfg.DefaultPolicy, nil
+		}
+
+		// use cookie if provided
+		if s := selectorCookie(r); s != "" {
+			return s, nil
+		}
+
+		return cfg.UnauthenticatedPolicy, nil
+	}
+}
+
+// NewRegexSelector selects the policy based on a user property
+// The policy for each case is configurable:
+//
+//	"policy_selector": {
+//	   "regex": {
+//	     "matches_policies": [
+//	       {"priority": 10, "property": "mail", "match": "mary@example.org", "policy": "qsfera"},
+//	       {"priority": 20, "property": "mail", "match": "[^@]+@example.org", "policy": "oc10"},
+//	       {"priority": 30, "property": "username", "match": "(dennis|feynman)", "policy": "qsfera"},
+//	       {"priority": 40, "property": "username", "match": ".+", "policy": "oc10"},
+//	       {"priority": 50, "property": "id", "match": "b1f74ec4-dd7e-11ef-a543-03775734d0f7", "policy": "qsfera"},
+//	       {"priority": 60, "property": "id", "match": "056fc874-dd7f-11ef-ba84-af6fca4b7289", "policy": "oc10"}
+//	     ],
+//	     "unauthenticated_policy": "oc10"
+//	   }
+//	 },
+//
+// This selector can be used in migration-scenarios or to set up sharded deployments
+func NewRegexSelector(cfg *config.RegexSelectorConf) Selector {
+	regexRules := []*regexRule{}
+	sort.Slice(cfg.MatchesPolicies, func(i, j int) bool {
+		return cfg.MatchesPolicies[i].Priority < cfg.MatchesPolicies[j].Priority
+	})
+	for i := range cfg.MatchesPolicies {
+		regexRules = append(regexRules, &regexRule{
+			property: cfg.MatchesPolicies[i].Property,
+			rule:     regexp.MustCompile(cfg.MatchesPolicies[i].Match),
+			policy:   cfg.MatchesPolicies[i].Policy,
+		})
+	}
+	return func(r *http.Request) (s string, err error) {
+		// use cookie first if provided
+		selectorCookie, err := r.Cookie(cfg.SelectorCookieName)
+		if err == nil {
+			return selectorCookie.Value, nil
+		}
+
+		// if no cookie is present, try to route by selector
+		if u, ok := revactx.ContextGetUser(r.Context()); ok {
+			for i := range regexRules {
+				switch regexRules[i].property {
+				case "mail":
+					if regexRules[i].rule.MatchString(u.Mail) {
+						return regexRules[i].policy, nil
+					}
+				case "username":
+					if regexRules[i].rule.MatchString(u.Username) {
+						return regexRules[i].policy, nil
+					}
+				case "id":
+					if u.Id != nil && regexRules[i].rule.MatchString(u.Id.OpaqueId) {
+						return regexRules[i].policy, nil
+					}
+				}
+			}
+			return cfg.DefaultPolicy, nil
+		}
+
+		return cfg.UnauthenticatedPolicy, nil
+	}
+}
+
+type regexRule struct {
+	property string
+	rule     *regexp.Regexp
+	policy   string
+}

Server/services/proxy/pkg/proxy/policy/selector_test.go

@@ -0,0 +1,145 @@
+package policy
+
+import (
+	"context"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	userv1beta1 "github.com/cs3org/go-cs3apis/cs3/identity/user/v1beta1"
+	"github.com/qsfera/server/pkg/oidc"
+	"github.com/qsfera/server/services/proxy/pkg/config"
+	revactx "github.com/opencloud-eu/reva/v2/pkg/ctx"
+)
+
+func TestLoadSelector(t *testing.T) {
+	type test struct {
+		cfg         *config.PolicySelector
+		expectedErr error
+	}
+	sCfg := &config.StaticSelectorConf{Policy: "reva"}
+	ccfg := &config.ClaimsSelectorConf{}
+	rcfg := &config.RegexSelectorConf{}
+
+	table := []test{
+		{cfg: &config.PolicySelector{Static: sCfg, Claims: ccfg, Regex: rcfg}, expectedErr: ErrMultipleSelectors},
+		{cfg: &config.PolicySelector{}, expectedErr: ErrSelectorConfigIncomplete},
+		{cfg: &config.PolicySelector{Static: sCfg}, expectedErr: nil},
+		{cfg: &config.PolicySelector{Claims: ccfg}, expectedErr: nil},
+		{cfg: &config.PolicySelector{Regex: rcfg}, expectedErr: nil},
+	}
+
+	for _, test := range table {
+		_, err := LoadSelector(test.cfg)
+		if err != test.expectedErr {
+			t.Errorf("Unexpected error %v", err)
+		}
+	}
+}
+
+func TestStaticSelector(t *testing.T) {
+	sel := NewStaticSelector(&config.StaticSelectorConf{Policy: "qsfera"})
+	req := httptest.NewRequest("GET", "https://example.org/foo", nil)
+	want := "qsfera"
+	got, err := sel(req)
+	if got != want {
+		t.Errorf("Expected policy %v got %v", want, got)
+	}
+
+	if err != nil {
+		t.Errorf("Unexpected error %v", err)
+	}
+
+	sel = NewStaticSelector(&config.StaticSelectorConf{Policy: "foo"})
+
+	want = "foo"
+	got, err = sel(req)
+	if got != want {
+		t.Errorf("Expected policy %v got %v", want, got)
+	}
+
+	if err != nil {
+		t.Errorf("Unexpected error %v", err)
+	}
+}
+
+type testCase struct {
+	Name     string
+	Context  context.Context
+	Cookie   *http.Cookie
+	Expected string
+}
+
+func TestClaimsSelector(t *testing.T) {
+	sel := NewClaimsSelector(&config.ClaimsSelectorConf{
+		DefaultPolicy:         "default",
+		UnauthenticatedPolicy: "unauthenticated",
+		SelectorCookieName:    SelectorCookieName,
+	})
+
+	var tests = []testCase{
+		{"unauthenticated", context.Background(), nil, "unauthenticated"},
+		{"default", oidc.NewContext(context.Background(), map[string]any{oidc.QsferaRoutingPolicy: ""}), nil, "default"},
+		{"claim-value", oidc.NewContext(context.Background(), map[string]any{oidc.QsferaRoutingPolicy: "qsfera.routing.policy-value"}), nil, "qsfera.routing.policy-value"},
+		{"cookie-only", context.Background(), &http.Cookie{Name: SelectorCookieName, Value: "cookie"}, "cookie"},
+		{"claim-can-override-cookie", oidc.NewContext(context.Background(), map[string]any{oidc.QsferaRoutingPolicy: "qsfera.routing.policy-value"}), &http.Cookie{Name: SelectorCookieName, Value: "cookie"}, "qsfera.routing.policy-value"},
+	}
+	for _, tc := range tests {
+		r := httptest.NewRequest("GET", "https://example.com", nil)
+		if tc.Cookie != nil {
+			r.AddCookie(tc.Cookie)
+		}
+		nr := r.WithContext(tc.Context)
+		got, err := sel(nr)
+		if err != nil {
+			t.Errorf("Unexpected error: %v", err)
+		}
+
+		if got != tc.Expected {
+			t.Errorf("Expected Policy %v got %v", tc.Expected, got)
+		}
+	}
+}
+
+func TestRegexSelector(t *testing.T) {
+	sel := NewRegexSelector(&config.RegexSelectorConf{
+		DefaultPolicy: "default",
+		MatchesPolicies: []config.RegexRuleConf{
+			{Priority: 10, Property: "mail", Match: "mary@example.org", Policy: "qsfera"},
+			{Priority: 20, Property: "mail", Match: "[^@]+@example.org", Policy: "oc10"},
+			{Priority: 30, Property: "username", Match: "(alan|feynman)", Policy: "qsfera"},
+			{Priority: 40, Property: "username", Match: ".+", Policy: "oc10"},
+			{Priority: 50, Property: "id", Match: "b1f74ec4-dd7e-11ef-a543-03775734d0f7", Policy: "qsfera"},
+			{Priority: 60, Property: "id", Match: "056fc874-dd7f-11ef-ba84-af6fca4b7289", Policy: "oc10"},
+		},
+		UnauthenticatedPolicy: "unauthenticated",
+	})
+
+	var tests = []testCase{
+		{"unauthenticated", context.Background(), nil, "unauthenticated"},
+		{"default", revactx.ContextSetUser(context.Background(), &userv1beta1.User{}), nil, "default"},
+		{"mail-qsfera", revactx.ContextSetUser(context.Background(), &userv1beta1.User{Mail: "mary@example.org"}), nil, "qsfera"},
+		{"mail-oc10", revactx.ContextSetUser(context.Background(), &userv1beta1.User{Mail: "alan@example.org"}), nil, "oc10"},
+		{"username-alan", revactx.ContextSetUser(context.Background(), &userv1beta1.User{Username: "alan"}), nil, "qsfera"},
+		{"username-feynman", revactx.ContextSetUser(context.Background(), &userv1beta1.User{Username: "feynman"}), nil, "qsfera"},
+		{"username-mary", revactx.ContextSetUser(context.Background(), &userv1beta1.User{Username: "mary"}), nil, "oc10"},
+		{"id-nil", revactx.ContextSetUser(context.Background(), &userv1beta1.User{Id: &userv1beta1.UserId{}}), nil, "default"},
+		{"id-1", revactx.ContextSetUser(context.Background(), &userv1beta1.User{Id: &userv1beta1.UserId{OpaqueId: "b1f74ec4-dd7e-11ef-a543-03775734d0f7"}}), nil, "qsfera"},
+		{"id-2", revactx.ContextSetUser(context.Background(), &userv1beta1.User{Id: &userv1beta1.UserId{OpaqueId: "056fc874-dd7f-11ef-ba84-af6fca4b7289"}}), nil, "oc10"},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.Name, func(t *testing.T) {
+			r := httptest.NewRequest("GET", "https://example.com", nil)
+			nr := r.WithContext(tc.Context)
+			got, err := sel(nr)
+			if err != nil {
+				t.Errorf("Unexpected error: %v", err)
+			}
+
+			if got != tc.Expected {
+				t.Errorf("Expected Policy %v got %v", tc.Expected, got)
+			}
+		})
+	}
+}

Server/services/proxy/pkg/proxy/proxy.go

@@ -0,0 +1,94 @@
+package proxy
+
+import (
+	"crypto/tls"
+	"crypto/x509"
+	"errors"
+	stdlog "log"
+	"net"
+	"net/http"
+	"net/http/httputil"
+	"os"
+	"time"
+
+	"github.com/qsfera/server/pkg/log"
+	"github.com/qsfera/server/services/proxy/pkg/config"
+	"github.com/qsfera/server/services/proxy/pkg/proxy/policy"
+	"github.com/qsfera/server/services/proxy/pkg/router"
+	"github.com/rs/zerolog"
+)
+
+// MultiHostReverseProxy extends "httputil" to support multiple hosts with different policies
+type MultiHostReverseProxy struct {
+	httputil.ReverseProxy
+	// Directors holds policy        route type        method    endpoint         Director
+	Directors      map[string]map[config.RouteType]map[string]map[string]func(req *http.Request)
+	PolicySelector policy.Selector
+	logger         log.Logger
+	config         *config.Config
+}
+
+// NewMultiHostReverseProxy creates a new MultiHostReverseProxy
+func NewMultiHostReverseProxy(opts ...Option) (*MultiHostReverseProxy, error) {
+	options := newOptions(opts...)
+
+	rp := &MultiHostReverseProxy{
+		ReverseProxy: httputil.ReverseProxy{
+			ErrorLog: stdlog.New(options.Logger, "", 0),
+		},
+		Directors: make(map[string]map[config.RouteType]map[string]map[string]func(req *http.Request)),
+		logger:    options.Logger,
+		config:    options.Config,
+	}
+
+	rp.Rewrite = func(r *httputil.ProxyRequest) {
+		ri := router.ContextRoutingInfo(r.In.Context())
+		ri.Rewrite()(r)
+	}
+
+	rp.ErrorHandler = func(rw http.ResponseWriter, req *http.Request, err error) {
+		reqLogger := zerolog.Ctx(req.Context())
+		if ev := reqLogger.Error(); ev.Enabled() {
+			ev.Err(err).Msg("error happened in MultiHostReverseProxy")
+		} else {
+			rp.logger.Err(err).Msg("error happened in MultiHostReverseProxy")
+		}
+		rw.WriteHeader(http.StatusBadGateway)
+	}
+
+	tlsConf := &tls.Config{
+		MinVersion:         tls.VersionTLS12,
+		InsecureSkipVerify: options.Config.InsecureBackends, //nolint:gosec
+	}
+	if options.Config.BackendHTTPSCACert != "" {
+		certs := x509.NewCertPool()
+		pemData, err := os.ReadFile(options.Config.BackendHTTPSCACert)
+		if err != nil {
+			return nil, err
+		}
+		if !certs.AppendCertsFromPEM(pemData) {
+			return nil, errors.New("Error initializing LDAP Backend. Adding CA cert failed")
+		}
+		tlsConf.RootCAs = certs
+	}
+	// equals http.DefaultTransport except TLSClientConfig
+	rp.Transport = &http.Transport{
+		Proxy: http.ProxyFromEnvironment,
+		DialContext: (&net.Dialer{
+			Timeout:   30 * time.Second,
+			KeepAlive: 30 * time.Second,
+			DualStack: true,
+		}).DialContext,
+		ForceAttemptHTTP2:     true,
+		MaxIdleConns:          100,
+		IdleConnTimeout:       90 * time.Second,
+		TLSHandshakeTimeout:   10 * time.Second,
+		ExpectContinueTimeout: 1 * time.Second,
+		TLSClientConfig:       tlsConf,
+	}
+	return rp, nil
+}
+
+func (p *MultiHostReverseProxy) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	p.ReverseProxy.ServeHTTP(w, r)
+}

Server/services/proxy/pkg/proxy/proxy_integration_test.go

@@ -0,0 +1,230 @@
+package proxy
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"net/http"
+	"net/http/httptest"
+	"net/url"
+	"testing"
+
+	"github.com/qsfera/server/pkg/log"
+	"github.com/qsfera/server/pkg/registry"
+	"github.com/qsfera/server/services/proxy/pkg/config"
+	"github.com/qsfera/server/services/proxy/pkg/router"
+	"go-micro.dev/v4/selector"
+)
+
+func TestProxyIntegration(t *testing.T) {
+	var tests = []testCase{
+		// Simple prefix route
+		test("simple_prefix", withPolicy("qsfera", withRoutes{{
+			Type:     config.PrefixRoute,
+			Endpoint: "/api",
+			Backend:  "http://api.example.com"},
+		})).withRequest("GET", "https://example.com/api", nil).
+			expectProxyTo("http://api.example.com/api"),
+
+		// Complex prefix route, different method
+		test("complex_prefix_post", withPolicy("qsfera", withRoutes{{
+			Type:     config.PrefixRoute,
+			Endpoint: "/api",
+			Backend:  "http://api.example.com/service1/"},
+		})).withRequest("POST", "https://example.com/api", nil).
+			expectProxyTo("http://api.example.com/service1/api"),
+
+		// Query route
+		test("query_route", withPolicy("qsfera", withRoutes{{
+			Type:     config.QueryRoute,
+			Endpoint: "/api?format=json",
+			Backend:  "http://backend/"},
+		})).withRequest("GET", "https://example.com/api?format=json", nil).
+			expectProxyTo("http://backend/api?format=json"),
+
+		// Regex route
+		test("regex_route", withPolicy("qsfera", withRoutes{{
+			Type:     config.RegexRoute,
+			Endpoint: `\/user\/(\d+)`,
+			Backend:  "http://backend/"},
+		})).withRequest("POST", "https://example.com/user/1234", nil).
+			expectProxyTo("http://backend/user/1234"),
+
+		// Multiple prefix routes 1
+		test("multiple_prefix", withPolicy("qsfera", withRoutes{
+			{
+				Type:     config.PrefixRoute,
+				Endpoint: "/api",
+				Backend:  "http://api.example.com",
+			},
+			{
+				Type:     config.PrefixRoute,
+				Endpoint: "/payment",
+				Backend:  "http://payment.example.com",
+			},
+		})).withRequest("GET", "https://example.com/payment", nil).
+			expectProxyTo("http://payment.example.com/payment"),
+
+		// Multiple prefix routes 2
+		test("multiple_prefix", withPolicy("qsfera", withRoutes{
+			{
+				Type:     config.PrefixRoute,
+				Endpoint: "/api",
+				Backend:  "http://api.example.com",
+			},
+			{
+				Type:     config.PrefixRoute,
+				Endpoint: "/payment",
+				Backend:  "http://payment.example.com",
+			},
+		})).withRequest("GET", "https://example.com/api", nil).
+			expectProxyTo("http://api.example.com/api"),
+
+		// Mixed route types
+		test("mixed_types", withPolicy("qsfera", withRoutes{
+			{
+				Type:     config.PrefixRoute,
+				Endpoint: "/api",
+				Backend:  "http://api.example.com",
+			},
+			{
+				Type:        config.RegexRoute,
+				Endpoint:    `\/user\/(\d+)`,
+				Backend:     "http://users.example.com",
+				ApacheVHost: false,
+			},
+		})).withRequest("GET", "https://example.com/api", nil).
+			expectProxyTo("http://api.example.com/api"),
+
+		// Mixed route types
+		test("mixed_types", withPolicy("qsfera", withRoutes{
+			{
+				Type:     config.PrefixRoute,
+				Endpoint: "/api",
+				Backend:  "http://api.example.com",
+			},
+			{
+				Type:        config.RegexRoute,
+				Endpoint:    `\/user\/(\d+)`,
+				Backend:     "http://users.example.com",
+				ApacheVHost: false,
+			},
+		})).withRequest("GET", "https://example.com/user/1234", nil).
+			expectProxyTo("http://users.example.com/user/1234"),
+	}
+
+	reg := registry.GetRegistry()
+	sel := selector.NewSelector(selector.Registry(reg))
+
+	for k := range tests {
+		t.Run(tests[k].id, func(t *testing.T) {
+			t.Parallel()
+			tc := tests[k]
+
+			rt := router.Middleware(sel, nil, tc.conf, log.NewLogger())
+			rp := newTestProxy(testConfig(tc.conf), func(req *http.Request) *http.Response {
+				if got, want := req.URL.String(), tc.expect.String(); got != want {
+					t.Errorf("Proxied url should be %v got %v", want, got)
+				}
+
+				if got, want := req.Method, tc.input.Method; got != want {
+					t.Errorf("Proxied request method should be %v got %v", want, got)
+				}
+
+				if got, want := req.Proto, tc.input.Proto; got != want {
+					t.Errorf("Proxied request proto should be %v got %v", want, got)
+				}
+
+				return &http.Response{
+					StatusCode: 200,
+					Body:       io.NopCloser(bytes.NewBufferString(`OK`)),
+					Header:     make(http.Header),
+				}
+			})
+
+			rr := httptest.NewRecorder()
+			rt(rp).ServeHTTP(rr, tc.input)
+			rsp := rr.Result()
+
+			if rsp.StatusCode != 200 {
+				t.Errorf("Expected status 200 from proxy-response got %v", rsp.StatusCode)
+			}
+
+			resultBody, err := io.ReadAll(rsp.Body)
+			if err != nil {
+				t.Fatal("Error reading result body")
+			}
+			if err = rsp.Body.Close(); err != nil {
+				t.Fatal("Error closing result body")
+			}
+
+			bodyString := string(resultBody)
+			if bodyString != `OK` {
+				t.Errorf("Result body of proxied response should be OK, got %v", bodyString)
+			}
+
+		})
+	}
+}
+
+func newTestProxy(cfg *config.Config, fn RoundTripFunc) *MultiHostReverseProxy {
+	rp, _ := NewMultiHostReverseProxy(Config(cfg))
+	rp.Transport = fn
+	return rp
+}
+
+type RoundTripFunc func(req *http.Request) *http.Response
+
+// RoundTrip .
+func (f RoundTripFunc) RoundTrip(req *http.Request) (*http.Response, error) {
+	return f(req), nil
+}
+
+type withRoutes []config.Route
+
+type testCase struct {
+	id     string
+	input  *http.Request
+	expect *url.URL
+	conf   []config.Policy
+}
+
+func test(id string, policies ...config.Policy) *testCase {
+	tc := &testCase{
+		id: id,
+	}
+	for k := range policies {
+		tc.conf = append(tc.conf, policies[k])
+	}
+
+	return tc
+}
+
+func withPolicy(name string, r withRoutes) config.Policy {
+	return config.Policy{Name: name, Routes: r}
+}
+
+func (tc *testCase) withRequest(method string, target string, body io.Reader) *testCase {
+	tc.input = httptest.NewRequest(method, target, body)
+	return tc
+}
+
+func (tc *testCase) expectProxyTo(strURL string) testCase {
+	pu, err := url.Parse(strURL)
+	if err != nil {
+		panic(fmt.Sprintf("Error parsing %v", strURL))
+	}
+
+	tc.expect = pu
+	return *tc
+}
+
+func testConfig(policy []config.Policy) *config.Config {
+	return &config.Config{
+		Debug:          config.Debug{},
+		HTTP:           config.HTTP{},
+		Policies:       policy,
+		OIDC:           config.OIDC{},
+		PolicySelector: nil,
+	}
+}