From d6cfc58950c990297f4bd148cb40482f46ec1d13 Mon Sep 17 00:00:00 2001
From: Katrina Rogan <krogan@lyft.com>
Date: Thu, 19 Dec 2019 17:05:39 -0800
Subject: [PATCH] Add flyte_client config endpoint handler (#44)

---
 cmd/entrypoints/serve.go            |  4 +++
 pkg/rpc/config/flyte_client.go      | 36 +++++++++++++++++++++++
 pkg/rpc/config/flyte_client_test.go | 44 +++++++++++++++++++++++++++++
 3 files changed, 84 insertions(+)
 create mode 100644 pkg/rpc/config/flyte_client.go
 create mode 100644 pkg/rpc/config/flyte_client_test.go

diff --git a/cmd/entrypoints/serve.go b/cmd/entrypoints/serve.go
index d0abe1ab11..6322b1935f 100644
--- a/cmd/entrypoints/serve.go
+++ b/cmd/entrypoints/serve.go
@@ -28,6 +28,7 @@ import (
 
 	"github.com/lyft/flyteadmin/pkg/config"
 	"github.com/lyft/flyteadmin/pkg/rpc/adminservice"
+	rpcConfig "github.com/lyft/flyteadmin/pkg/rpc/config"
 
 	"github.com/spf13/cobra"
 
@@ -128,6 +129,9 @@ func newHTTPServer(ctx context.Context, cfg *config.ServerConfig, authContext in
 	// This endpoint will serve the OpenAPI2 spec generated by the swagger protoc plugin, and bundled by go-bindata
 	mux.HandleFunc("/api/v1/openapi", GetHandleOpenapiSpec(ctx))
 
+	// Handles serving config values required to initialize a flyte-client config
+	mux.HandleFunc("/config/v1/flyte_client", rpcConfig.HandleFlyteCliConfigFunc(ctx, cfg))
+
 	var gwmuxOptions = make([]runtime.ServeMuxOption, 0)
 	// This option means that http requests are served with protobufs, instead of json. We always want this.
 	gwmuxOptions = append(gwmuxOptions, runtime.WithMarshalerOption("application/octet-stream", &runtime.ProtoMarshaller{}))
diff --git a/pkg/rpc/config/flyte_client.go b/pkg/rpc/config/flyte_client.go
new file mode 100644
index 0000000000..6216cc9029
--- /dev/null
+++ b/pkg/rpc/config/flyte_client.go
@@ -0,0 +1,36 @@
+package config
+
+import (
+	"context"
+	"encoding/json"
+	"net/http"
+
+	"github.com/lyft/flyteadmin/pkg/config"
+	"github.com/lyft/flytestdlib/logger"
+)
+
+const (
+	clientID        = "client_id"
+	redirectURI     = "redirect_uri"
+	authMetadataKey = "authorization_metadata_key"
+)
+
+func HandleFlyteCliConfigFunc(ctx context.Context, cfg *config.ServerConfig) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		configValues := map[string]string{
+			clientID:        cfg.Security.Oauth.ClientID,
+			redirectURI:     cfg.Security.Oauth.CallbackURL,
+			authMetadataKey: cfg.Security.Oauth.GrpcAuthorizationHeader,
+		}
+		configJSON, err := json.Marshal(configValues)
+		if err != nil {
+			logger.Infof(ctx, "Failed to marshal flyte_client config to JSON with err: %v", err)
+			w.WriteHeader(http.StatusInternalServerError)
+			return
+		}
+		_, err = w.Write(configJSON)
+		if err != nil {
+			logger.Warningf(ctx, "Failed to write config json [%+v] with err: %v", string(configJSON), err)
+		}
+	}
+}
diff --git a/pkg/rpc/config/flyte_client_test.go b/pkg/rpc/config/flyte_client_test.go
new file mode 100644
index 0000000000..d0e06116a8
--- /dev/null
+++ b/pkg/rpc/config/flyte_client_test.go
@@ -0,0 +1,44 @@
+package config
+
+import (
+	"context"
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	authConfig "github.com/lyft/flyteadmin/pkg/auth/config"
+	"github.com/lyft/flyteadmin/pkg/config"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestHandleFlyteCliConfigFunc(t *testing.T) {
+	testClientID := "12345"
+	testRedirectURI := "localhost:12345/callback"
+	testAuthMetadataKey := "flyte-authorization"
+
+	handleFlyteCliConfigFunc := HandleFlyteCliConfigFunc(context.Background(), &config.ServerConfig{
+		Security: config.ServerSecurityOptions{
+			Oauth: authConfig.OAuthOptions{
+				ClientID:                testClientID,
+				CallbackURL:             testRedirectURI,
+				GrpcAuthorizationHeader: testAuthMetadataKey,
+			},
+		},
+	})
+
+	responseRecorder := httptest.NewRecorder()
+	handleFlyteCliConfigFunc(responseRecorder, nil)
+	assert.Equal(t, http.StatusOK, responseRecorder.Code)
+	responseBody := responseRecorder.Body
+	var responseBodyMap map[string]string
+	err := json.Unmarshal(responseBody.Bytes(), &responseBodyMap)
+	if err != nil {
+		t.Fatalf("Failed to unmarshal response body with err: %v", err)
+	}
+	assert.EqualValues(t, map[string]string{
+		clientID:        testClientID,
+		redirectURI:     testRedirectURI,
+		authMetadataKey: testAuthMetadataKey,
+	}, responseBodyMap)
+}