feat: add a v1 and v2 handler to the proxy for different config cdn u…

…rls (#21) * add a v1 and v2 handler that uses different devcycle clients which fetch from v1 and v2 cdn endpoints respectively * store an override config that's per instance level * pass in v1 arg * path fix * path fix v2 * use released version of sdk --------- Co-authored-by: Jamie Sinn <[email protected]>
DevCycleHQ · Aug 23, 2024 · e5c3aab · e5c3aab
1 parent 508abab
commit e5c3aab
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Showing 5 changed files with 90 additions and 40 deletions.
diff --git a/go.mod b/go.mod
@@ -3,10 +3,11 @@ module github.com/devcyclehq/sdk-proxy
 go 1.20
 
 require (
-	github.com/devcyclehq/go-server-sdk/v2 v2.17.0
+	github.com/devcyclehq/go-server-sdk/v2 v2.18.1
 	github.com/gin-gonic/gin v1.10.0
 	github.com/kelseyhightower/envconfig v1.4.0
 	github.com/kr/pretty v0.3.1
+	github.com/launchdarkly/eventsource v1.7.1
 	github.com/stretchr/testify v1.9.0
 )
 
@@ -27,7 +28,6 @@ require (
 	github.com/json-iterator/go v1.1.12 // indirect
 	github.com/klauspost/cpuid/v2 v2.2.7 // indirect
 	github.com/kr/text v0.2.0 // indirect
-	github.com/launchdarkly/eventsource v1.7.1 // indirect
 	github.com/leodido/go-urn v1.4.0 // indirect
 	github.com/matryer/try v0.0.0-20161228173917-9ac251b645a2 // indirect
 	github.com/mattn/go-isatty v0.0.20 // indirect

diff --git a/go.sum b/go.sum
@@ -11,10 +11,14 @@ github.com/creack/pty v1.1.9/go.mod h1:oKZEueFk5CKHvIhNR5MUki03XCEU+Q6VDXinZuGJ3
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
-github.com/devcyclehq/go-server-sdk/v2 v2.16.1 h1:NZ0vHZhhrPOb2hbU/r5sIIDSG4tPc+TiO/ovJaP0Gk8=
-github.com/devcyclehq/go-server-sdk/v2 v2.16.1/go.mod h1:DzKrJ4s2apfphFwB/Aq8YDf7brB+NDr6IxX0TNi2c24=
-github.com/devcyclehq/go-server-sdk/v2 v2.17.0 h1:eBvoJesVPYvy7htJBjhIWRGbQq5fsmlcv4nvsrHqPDU=
-github.com/devcyclehq/go-server-sdk/v2 v2.17.0/go.mod h1:DzKrJ4s2apfphFwB/Aq8YDf7brB+NDr6IxX0TNi2c24=
+github.com/devcyclehq/go-server-sdk/v2 v2.18.0 h1:9STdu/bTnrjM1cFh3OJddO4nxAaAUqlOAO180x6SWpk=
+github.com/devcyclehq/go-server-sdk/v2 v2.18.0/go.mod h1:DzKrJ4s2apfphFwB/Aq8YDf7brB+NDr6IxX0TNi2c24=
+github.com/devcyclehq/go-server-sdk/v2 v2.18.1-0.20240822213335-a3201264237c h1:HABqfIWonwH731k8kd+yYLExjsuVH5S+xL9Ed3Kywhw=
+github.com/devcyclehq/go-server-sdk/v2 v2.18.1-0.20240822213335-a3201264237c/go.mod h1:DzKrJ4s2apfphFwB/Aq8YDf7brB+NDr6IxX0TNi2c24=
+github.com/devcyclehq/go-server-sdk/v2 v2.18.1-0.20240823134625-106c09774905 h1:tOTq2TbgeYtdFuaOl71Sups5p8setOA5VHan6DRGOnU=
+github.com/devcyclehq/go-server-sdk/v2 v2.18.1-0.20240823134625-106c09774905/go.mod h1:DzKrJ4s2apfphFwB/Aq8YDf7brB+NDr6IxX0TNi2c24=
+github.com/devcyclehq/go-server-sdk/v2 v2.18.1 h1:4Rwxr0Sx4S56zGgSqm0C06Xj88038iYVbWZinpPx8C4=
+github.com/devcyclehq/go-server-sdk/v2 v2.18.1/go.mod h1:DzKrJ4s2apfphFwB/Aq8YDf7brB+NDr6IxX0TNi2c24=
 github.com/gabriel-vasile/mimetype v1.4.3 h1:in2uUcidCuFcDKtdcBxlR0rJ1+fsokWf+uqxgUFjbI0=
 github.com/gabriel-vasile/mimetype v1.4.3/go.mod h1:d8uq/6HKRL6CGdk+aubisF/M5GcPfT7nKyLpA0lbSSk=
 github.com/gin-contrib/sse v0.1.0 h1:Y/yl/+YNO8GZSjAhjMsSuLt29uWRFHdHYUb5lYOV9qE=

diff --git a/http_endpoints.go b/http_endpoints.go
@@ -111,53 +111,58 @@ func BatchEvents() gin.HandlerFunc {
 	}
 }
 
-func GetConfig() gin.HandlerFunc {
+func GetConfig(client *devcycle.Client, version ...string) gin.HandlerFunc {
 	return func(c *gin.Context) {
 		instance := c.Value("instance").(*ProxyInstance)
-		client := c.Value("devcycle").(*devcycle.Client)
 
 		if c.Param("sdkKey") == "" || !strings.HasSuffix(c.Param("sdkKey"), ".json") {
 			c.AbortWithStatus(http.StatusForbidden)
 			return
 		}
-		var ret []byte
-		rawConfig, etag, err := client.GetRawConfig()
-		if err != nil {
-			c.JSON(http.StatusInternalServerError, gin.H{})
-			return
-		}
-		if instance.SSEEnabled {
-			config := map[string]interface{}{}
-			err = json.Unmarshal(rawConfig, &config)
+		var ret, rawConfig []byte
+		var etag, lm string
+		var err error
+		if client != nil {
+			rawConfig, etag, lm, err = client.GetRawConfig()
 			if err != nil {
 				c.JSON(http.StatusInternalServerError, gin.H{})
 				return
 			}
-			hostname := fmt.Sprintf("http://%s:%d", instance.SSEHostname, instance.HTTPPort)
-			// This is the only indicator that a unix socket request was made
-			if c.Request.RemoteAddr == "" {
-				hostname = fmt.Sprintf("unix:%s", instance.UnixSocketPath)
-			}
-			fmt.Println(c.Request)
-			if val, ok := config["sse"]; ok {
-				path := val.(map[string]interface{})["path"].(string)
-
-				config["sse"] = devcycle_api.SSEHost{
-					Hostname: hostname,
-					Path:     path,
+			if instance.SSEEnabled {
+				config := map[string]interface{}{}
+				err = json.Unmarshal(rawConfig, &config)
+				if err != nil {
+					c.JSON(http.StatusInternalServerError, gin.H{})
+					return
+				}
+				hostname := fmt.Sprintf("http://%s:%d", instance.SSEHostname, instance.HTTPPort)
+				// This is the only indicator that a unix socket request was made
+				if c.Request.RemoteAddr == "" {
+					hostname = fmt.Sprintf("unix:%s", instance.UnixSocketPath)
+				}
+				fmt.Println(c.Request)
+				if val, ok := config["sse"]; ok {
+					path := val.(map[string]interface{})["path"].(string)
+
+					config["sse"] = devcycle_api.SSEHost{
+						Hostname: hostname,
+						Path:     path,
+					}
 				}
-			}
-
-			ret, err = json.Marshal(config)
-		} else {
-			ret = rawConfig
-		}
 
-		if err != nil {
-			c.JSON(http.StatusInternalServerError, gin.H{})
-			return
+				ret, err = json.Marshal(config)
+			} else {
+				ret = rawConfig
+			}
+			if err != nil {
+				c.JSON(http.StatusInternalServerError, gin.H{})
+				return
+			}
+		} else if client == nil && len(version) > 0 {
+			ret, etag, lm = instance.BypassSDKConfig(version[0])
 		}
 		c.Header("ETag", etag)
+		c.Header("Last-Modified", lm)
 		c.Data(http.StatusOK, "application/json", ret)
 	}
 }

diff --git a/options.go b/options.go
@@ -5,7 +5,9 @@ import (
 	"fmt"
 	"github.com/devcyclehq/go-server-sdk/v2/api"
 	"github.com/launchdarkly/eventsource"
+	"io"
 	"log"
+	"net/http"
 	"os"
 	"runtime"
 	"time"
@@ -38,6 +40,7 @@ type ProxyInstance struct {
 	dvcClient             *devcycle.Client
 	sseServer             *eventsource.Server
 	sseEvents             chan api.ClientEvent
+	bypassConfig          []byte
 }
 
 type SDKConfig struct {
@@ -73,13 +76,45 @@ func (i *ProxyInstance) BuildDevCycleOptions() *devcycle.Options {
 		EnableBetaRealtimeUpdates:    i.SSEEnabled,
 		AdvancedOptions: devcycle.AdvancedOptions{
 			OverridePlatformData: &i.PlatformData,
+			OverrideConfigWithV1: false,
 		},
 		ClientEventHandler: i.sseEvents,
 	}
 	options.CheckDefaults()
 	return &options
 }
 
+func (i *ProxyInstance) BypassSDKConfig(version string) (config []byte, etag, lastModified string) {
+
+	request, err := http.NewRequest("GET", fmt.Sprintf("https://config-cdn.devcycle.com/config/%s/server/%s.json", version, i.SDKKey), nil)
+	if err != nil {
+		return i.bypassConfig, "", ""
+	}
+
+	resp, err := http.DefaultClient.Do(request)
+
+	if err != nil {
+		return i.bypassConfig, "", ""
+	}
+
+	if resp.StatusCode == http.StatusNotModified {
+		return i.bypassConfig, resp.Header.Get("ETag"), resp.Header.Get("Last-Modified")
+	}
+
+	if resp.StatusCode != http.StatusOK {
+		return i.bypassConfig, "", ""
+	}
+
+	body, err := io.ReadAll(resp.Body)
+	defer resp.Body.Close()
+	if err != nil {
+		return i.bypassConfig, "", ""
+	}
+
+	i.bypassConfig = body
+	return i.bypassConfig, resp.Header.Get("ETag"), resp.Header.Get("Last-Modified")
+}
+
 func (i *ProxyInstance) EventRebroadcaster() {
 	for event := range i.sseEvents {
 		if event.EventType == api.ClientEventType_RealtimeUpdates {

diff --git a/proxy.go b/proxy.go
@@ -35,6 +35,9 @@ func NewBucketingProxyInstance(instance *ProxyInstance) (*ProxyInstance, error)
 
 	options := instance.BuildDevCycleOptions()
 	client, err := devcycle.NewClient(instance.SDKKey, options)
+	if err != nil {
+		return nil, fmt.Errorf("error creating DevCycle client: %v", err)
+	}
 	instance.dvcClient = client
 
 	r := newRouter(client, instance)
@@ -116,9 +119,12 @@ func newRouter(client *devcycle.Client, instance *ProxyInstance) *gin.Engine {
 	}
 	configCDNv1 := r.Group("/config/v1")
 	{
-		configCDNv1.GET("/server/:sdkKey", GetConfig())
+		configCDNv1.GET("/server/:sdkKey", GetConfig(nil, "v1"))
+	}
+	configCDNv2 := r.Group("/config/v2")
+	{
+		configCDNv2.GET("/server/:sdkKey", GetConfig(client))
 	}
-
 	r.GET("/event-stream", SSE())
 
 	return r