Fns now annotated with invoke urls, as per triggers (#1172)

Clone of the trigger work to inject invoke urls into the annotations
on a fn when it is returned from the server.

Small changes to trigges code following code review of the fn code.

api/server/fn_annotator.go

@@ -0,0 +1,63 @@
+package server
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/fnproject/fn/api/models"
+	"github.com/gin-gonic/gin"
+)
+
+//FnAnnotator Is used to inject trigger context (such as request URLs) into outbound trigger resources
+type FnAnnotator interface {
+	// Annotates a trigger on read
+	AnnotateFn(ctx *gin.Context, a *models.App, fn *models.Fn) (*models.Fn, error)
+}
+
+type requestBasedFnAnnotator struct{}
+
+func annotateFnWithBaseURL(baseURL string, app *models.App, fn *models.Fn) (*models.Fn, error) {
+
+	baseURL = strings.TrimSuffix(baseURL, "/")
+	src := strings.TrimPrefix(fn.ID, "/")
+	triggerPath := fmt.Sprintf("%s/invoke/%s", baseURL, src)
+
+	newT := fn.Clone()
+	newAnnotations, err := newT.Annotations.With(models.FnInvokeEndpointAnnotation, triggerPath)
+	if err != nil {
+		return nil, err
+	}
+	newT.Annotations = newAnnotations
+	return newT, nil
+}
+
+func (tp *requestBasedFnAnnotator) AnnotateFn(ctx *gin.Context, app *models.App, t *models.Fn) (*models.Fn, error) {
+
+	//No, I don't feel good about myself either
+	scheme := "http"
+	if ctx.Request.TLS != nil {
+		scheme = "https"
+	}
+
+	return annotateFnWithBaseURL(fmt.Sprintf("%s://%s", scheme, ctx.Request.Host), app, t)
+}
+
+//NewRequestBasedFnAnnotator creates a FnAnnotator that inspects the incoming request host and port, and uses this to generate fn invoke endpoint URLs based on those
+func NewRequestBasedFnAnnotator() FnAnnotator {
+	return &requestBasedFnAnnotator{}
+}
+
+type staticURLFnAnnotator struct {
+	baseURL string
+}
+
+//NewStaticURLFnAnnotator annotates triggers bases on a given, specified URL base - e.g. "https://my.domain" --->  "https://my.domain/t/app/source"
+func NewStaticURLFnAnnotator(baseURL string) FnAnnotator {
+
+	return &staticURLFnAnnotator{baseURL: baseURL}
+}
+
+func (s *staticURLFnAnnotator) AnnotateFn(ctx *gin.Context, app *models.App, trigger *models.Fn) (*models.Fn, error) {
+	return annotateFnWithBaseURL(s.baseURL, app, trigger)
+
+}

api/server/fn_annotator_test.go

@@ -0,0 +1,133 @@
+package server
+
+import (
+	bytes2 "bytes"
+	"crypto/tls"
+	"encoding/json"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/fnproject/fn/api/models"
+	"github.com/gin-gonic/gin"
+)
+
+func TestAnnotateFnDefaultProvider(t *testing.T) {
+
+	app := &models.App{
+		ID:   "app_id",
+		Name: "myApp",
+	}
+
+	tr := &models.Fn{
+		ID:    "fnID",
+		Name:  "myFn",
+		AppID: app.ID,
+	}
+
+	// defaults the fn endpoint to the base URL if it's not already set
+	tep := NewRequestBasedFnAnnotator()
+
+	c, _ := gin.CreateTestContext(httptest.NewRecorder())
+	c.Request = httptest.NewRequest("GET", "/v2/foo/bar", bytes2.NewBuffer([]byte{}))
+	c.Request.Host = "my-server.com:8192"
+	newT, err := tep.AnnotateFn(c, app, tr)
+
+	if err != nil {
+		t.Fatalf("expected no error, got %s", err)
+	}
+
+	bytes, got := newT.Annotations.Get(models.FnInvokeEndpointAnnotation)
+	if !got {
+		t.Fatalf("Expecting annotation to be present but got %v", newT.Annotations)
+	}
+
+	var annot string
+	err = json.Unmarshal(bytes, &annot)
+	if err != nil {
+		t.Fatalf("Couldn't get annotation")
+	}
+
+	expected := "http://my-server.com:8192/invoke/fnID"
+	if annot != expected {
+		t.Errorf("expected annotation to be %s but was %s", expected, annot)
+	}
+}
+
+func TestHttpsFn(t *testing.T) {
+
+	app := &models.App{
+		ID:   "app_id",
+		Name: "myApp",
+	}
+
+	tr := &models.Fn{
+		ID:    "fnID",
+		Name:  "myFn",
+		AppID: app.ID,
+	}
+
+	// defaults the Fn endpoint to the base URL if it's not already set
+	tep := NewRequestBasedFnAnnotator()
+
+	c, _ := gin.CreateTestContext(httptest.NewRecorder())
+	c.Request = httptest.NewRequest("GET", "/v2/foo/bar", bytes2.NewBuffer([]byte{}))
+	c.Request.Host = "my-server.com:8192"
+	c.Request.TLS = &tls.ConnectionState{}
+
+	newT, err := tep.AnnotateFn(c, app, tr)
+
+	if err != nil {
+		t.Fatalf("expected no error, got %s", err)
+	}
+
+	bytes, got := newT.Annotations.Get(models.FnInvokeEndpointAnnotation)
+	if !got {
+		t.Fatalf("Expecting annotation  to be present but got %v", newT.Annotations)
+	}
+	var annot string
+	err = json.Unmarshal(bytes, &annot)
+	if err != nil {
+		t.Fatalf("Couldn't get annotation")
+	}
+
+	expected := "https://my-server.com:8192/invoke/fnID"
+	if annot != expected {
+		t.Errorf("expected annotation to be %s but was %s", expected, annot)
+	}
+}
+
+func TestStaticUrlFnAnnotator(t *testing.T) {
+	a := NewStaticURLFnAnnotator("http://foo.bar.com/somewhere")
+
+	app := &models.App{
+		ID:   "app_id",
+		Name: "myApp",
+	}
+
+	tr := &models.Fn{
+		ID:    "fnID",
+		Name:  "myFn",
+		AppID: app.ID,
+	}
+
+	newT, err := a.AnnotateFn(nil, app, tr)
+	if err != nil {
+		t.Fatalf("failed when should have succeeded: %s", err)
+	}
+
+	bytes, got := newT.Annotations.Get(models.FnInvokeEndpointAnnotation)
+	if !got {
+		t.Fatalf("Expecting annotation to be present but got %v", newT.Annotations)
+	}
+	var annot string
+	err = json.Unmarshal(bytes, &annot)
+	if err != nil {
+		t.Fatalf("Couldn't get annotation")
+	}
+
+	expected := "http://foo.bar.com/somewhere/invoke/fnID"
+	if annot != expected {
+		t.Errorf("expected annotation to be %s but was %s", expected, annot)
+	}
+
+}

api/server/fns_get.go

@@ -1,6 +1,7 @@
 package server
 
 import (
+	"fmt"
 	"net/http"
 
 	"github.com/fnproject/fn/api"
@@ -9,11 +10,24 @@ import (
 
 func (s *Server) handleFnGet(c *gin.Context) {
 	ctx := c.Request.Context()
+
 	f, err := s.datastore.GetFnByID(ctx, c.Param(api.ParamFnID))
 	if err != nil {
 		handleErrorResponse(c, err)
 		return
 	}
 
+	app, err := s.datastore.GetAppByID(ctx, f.AppID)
+	if err != nil {
+		handleErrorResponse(c, fmt.Errorf("unexpected error - fn app not available: %s", err))
+		return
+	}
+
+	f, err = s.fnAnnotator.AnnotateFn(c, app, f)
+	if err != nil {
+		handleErrorResponse(c, err)
+		return
+	}
+
 	c.JSON(http.StatusOK, f)
 }

api/server/fns_list.go

@@ -1,6 +1,7 @@
 package server
 
 import (
+	"fmt"
 	"net/http"
 
 	"github.com/fnproject/fn/api/models"
@@ -21,5 +22,30 @@ func (s *Server) handleFnList(c *gin.Context) {
 		return
 	}
 
+	// Annotate the outbound fns
+
+	// this is fairly cludgy bit hard to do in datastore middleware confidently
+	appCache := make(map[string]*models.App)
+
+	for idx, f := range fns.Items {
+		app, ok := appCache[f.AppID]
+		if !ok {
+			gotApp, err := s.Datastore().GetAppByID(ctx, f.AppID)
+			if err != nil {
+				handleErrorResponse(c, fmt.Errorf("failed to get app for fn %s", err))
+				return
+			}
+			app = gotApp
+			appCache[app.ID] = gotApp
+		}
+
+		newF, err := s.fnAnnotator.AnnotateFn(c, app, f)
+		if err != nil {
+			handleErrorResponse(c, err)
+			return
+		}
+		fns.Items[idx] = newF
+	}
+
 	c.JSON(http.StatusOK, fns)
 }

api/server/fns_test.go

@@ -358,3 +358,53 @@ func TestFnGet(t *testing.T) {
 		}
 	}
 }
+
+func TestFnInvokeEndpointAnnotations(t *testing.T) {
+	a := &models.App{ID: "app_id", Name: "myapp"}
+	fn := &models.Fn{ID: "fnid", AppID: a.ID, Name: "fnname"}
+
+	commonDS := datastore.NewMockInit([]*models.App{a}, []*models.Fn{fn})
+
+	srv := testServer(commonDS, &mqs.Mock{}, logs.NewMock(), nil, ServerTypeAPI)
+
+	_, rec := routerRequest(t, srv.Router, "GET", "/v2/fns/fnid", bytes.NewBuffer([]byte("")))
+
+	if rec.Code != http.StatusOK {
+		t.Fatalf("expected code %d != 200", rec.Code)
+	}
+	var fnGet models.Fn
+	err := json.NewDecoder(rec.Body).Decode(&fnGet)
+	if err != nil {
+		t.Fatalf("Invalid json from server %s", err)
+	}
+
+	const fnEndpoint = "fnproject.io/fn/invokeEndpoint"
+	v, err := fnGet.Annotations.GetString(fnEndpoint)
+	if err != nil {
+		t.Fatalf("failed to get fn %s", err)
+	}
+	if v != "http://127.0.0.1:8080/invoke/fnid" {
+		t.Errorf("unexpected fn val %s", v)
+	}
+
+	_, rec = routerRequest(t, srv.Router, "GET", fmt.Sprintf("/v2/fns?app_id=%s", a.ID), nil)
+
+	if rec.Code != http.StatusOK {
+		t.Fatalf("expected code %d != 200", rec.Code)
+	}
+
+	var resp models.FnList
+	err = json.NewDecoder(rec.Body).Decode(&resp)
+	if err != nil {
+		t.Fatalf("Invalid json from server %s : %s", err, string(rec.Body.Bytes()))
+	}
+
+	if len(resp.Items) != 1 {
+		t.Fatalf("Unexpected fn list result, %v", resp)
+	}
+
+	v, err = resp.Items[0].Annotations.GetString(fnEndpoint)
+	if v != "http://127.0.0.1:8080/invoke/fnid" {
+		t.Errorf("unexpected fn val %s", v)
+	}
+}

api/server/server.go

@@ -205,6 +205,7 @@ type Server struct {
 	apiMiddlewares         []fnext.Middleware
 	promExporter           *prometheus.Exporter
 	triggerAnnotator       TriggerAnnotator
+	fnAnnotator            FnAnnotator
 	// Extensions can append to this list of contexts so that cancellations are properly handled.
 	extraCtxs []context.Context
 }
@@ -257,8 +258,10 @@ func NewFromEnv(ctx context.Context, opts ...Option) *Server {
 	if publicLBURL != "" {
 		logrus.Infof("using LB Base URL: '%s'", publicLBURL)
 		opts = append(opts, WithTriggerAnnotator(NewStaticURLTriggerAnnotator(publicLBURL)))
+		opts = append(opts, WithFnAnnotator(NewStaticURLFnAnnotator(publicLBURL)))
 	} else {
 		opts = append(opts, WithTriggerAnnotator(NewRequestBasedTriggerAnnotator()))
+		opts = append(opts, WithFnAnnotator(NewRequestBasedFnAnnotator()))
 	}
 
 	// Agent handling depends on node type and several other options so it must be the last processed option.
@@ -580,6 +583,14 @@ func WithTriggerAnnotator(provider TriggerAnnotator) Option {
 	}
 }
 
+//WithFnAnnotator adds a fnEndpoint provider to the server
+func WithFnAnnotator(provider FnAnnotator) Option {
+	return func(ctx context.Context, s *Server) error {
+		s.fnAnnotator = provider
+		return nil
+	}
+}
+
 // WithAdminServer starts the admin server on the specified port.
 func WithAdminServer(port int) Option {
 	return func(ctx context.Context, s *Server) error {

api/server/server_test.go

@@ -38,6 +38,7 @@ func testServer(ds models.Datastore, mq models.MessageQueue, logDB models.LogSto
 		WithAgent(rnr),
 		WithType(nodeType),
 		WithTriggerAnnotator(NewRequestBasedTriggerAnnotator()),
+		WithFnAnnotator(NewRequestBasedFnAnnotator()),
 	)...)
 }
 

api/server/trigger_get.go

@@ -2,9 +2,10 @@ package server
 
 import (
 	"fmt"
+	"net/http"
+
 	"github.com/fnproject/fn/api"
 	"github.com/gin-gonic/gin"
-	"net/http"
 )
 
 func (s *Server) handleTriggerGet(c *gin.Context) {
@@ -20,6 +21,7 @@ func (s *Server) handleTriggerGet(c *gin.Context) {
 
 	if err != nil {
 		handleErrorResponse(c, fmt.Errorf("unexpected error - trigger app not available: %s", err))
+		return
 	}
 
 	trigger, err = s.triggerAnnotator.AnnotateTrigger(c, app, trigger)

api/server/trigger_list.go

@@ -4,6 +4,7 @@ import (
 	"net/http"
 
 	"fmt"
+
 	"github.com/fnproject/fn/api/models"
 	"github.com/gin-gonic/gin"
 )
@@ -30,10 +31,8 @@ func (s *Server) handleTriggerList(c *gin.Context) {
 	}
 
 	// Annotate the outbound triggers
-
 	// this is fairly cludgy bit hard to do in datastore middleware confidently
 	appCache := make(map[string]*models.App)
-	newTriggers := make([]*models.Trigger, len(triggers.Items))
 
 	for idx, t := range triggers.Items {
 		app, ok := appCache[t.AppID]
@@ -52,9 +51,8 @@ func (s *Server) handleTriggerList(c *gin.Context) {
 			handleErrorResponse(c, err)
 			return
 		}
-		newTriggers[idx] = newT
+		triggers.Items[idx] = newT
 	}
 
-	triggers.Items = newTriggers
 	c.JSON(http.StatusOK, triggers)
 }