changes to fetch flags from S3 - UL-916

unlaunchio/client/factory.go

@@ -2,12 +2,15 @@ package client
 
 import (
 	"errors"
+	"fmt"
+	"strings"
+	"sync/atomic"
+
 	"github.com/unlaunch/go-sdk/unlaunchio/engine"
 	"github.com/unlaunch/go-sdk/unlaunchio/service"
 	"github.com/unlaunch/go-sdk/unlaunchio/service/api"
 	"github.com/unlaunch/go-sdk/unlaunchio/util"
 	"github.com/unlaunch/go-sdk/unlaunchio/util/logger"
-	"strings"
 )
 
 // UnlaunchFactory ...
@@ -17,6 +20,8 @@ type UnlaunchFactory struct {
 	logger logger.Interface
 }
 
+var sync0Complete atomic.Value
+
 // NewUnlaunchClientFactory is a factory
 func NewUnlaunchClientFactory(SDKKey string, cfg *UnlaunchClientConfig) (*UnlaunchFactory, error) {
 
@@ -49,33 +54,80 @@ func (f *UnlaunchFactory) Client() Client {
 		}
 	}
 
+	if sync0Complete.Load() == nil {
+		sync0Complete.Store(true) // we preemptively marked it as done
+		client := f.sync0()
+		if client == nil { // regular server sync
+			return f.regularServerSync()
+		} else {
+			return client
+		}
+
+	} else {
+		return f.regularServerSync()
+	}
+}
+
+func (f *UnlaunchFactory) regularServerSync() Client {
+
 	eventsRecorder := api.NewHTTPEventsRecorder(
 		false,
-		util.NewHTTPClient(f.sdkKey, f.cfg.Host, f.cfg.HTTPTimeout, f.logger),
+		util.NewHTTPClient(f.sdkKey, f.cfg.Host, f.cfg.HTTPTimeout, f.logger, false),
 		"/api/v1/impressions",
 		f.cfg.MetricsFlushInterval,
 		f.cfg.MetricsQueueSize,
 		"impressions",
 		f.logger)
 
 	eventsCounts := api.NewEventsCountAggregator(
-		util.NewHTTPClient(f.sdkKey, f.cfg.Host, f.cfg.HTTPTimeout, f.logger),
+		util.NewHTTPClient(f.sdkKey, f.cfg.Host, f.cfg.HTTPTimeout, f.logger, false),
 		"/api/v1/events",
 		f.cfg.MetricsFlushInterval,
 		f.cfg.MetricsQueueSize,
 		f.logger)
 
-	hc := util.NewHTTPClient(f.sdkKey, f.cfg.Host, f.cfg.HTTPTimeout, f.logger)
+	hc := util.NewHTTPClient(f.sdkKey, f.cfg.Host, f.cfg.HTTPTimeout, f.logger, false)
 
 	return &SimpleClient{
 		FeatureStore: service.NewHTTPFeatureStore(
 			hc,
 			f.cfg.PollingInterval,
-			f.logger),
+			f.logger,
+			false,
+			nil),
 		eventsRecorder:        eventsRecorder,
 		eventsCountAggregator: eventsCounts,
 		logger:                f.logger,
 		evaluator:             engine.NewEvaluator(f.logger),
 	}
+}
+
+func (f *UnlaunchFactory) sync0() Client {
+	hc := util.NewHTTPClient(f.sdkKey, f.cfg.Host, f.cfg.HTTPTimeout, f.logger, true)
+
+	res, err := hc.Get("https://app-qa-unlaunch-io-master-flags.s3-us-west-1.amazonaws.com")
+
+	if res == nil {
+		return nil
+	}
+
+	if err != nil {
+		f.logger.Error("[HTTP GET] error reading body", err)
+		return nil
+	}
+
+	f.logger.Debug(fmt.Sprintf("[HTTP GET] data: %d", res))
+
+	return &SimpleClient{
+		FeatureStore: service.NewHTTPFeatureStore(
+			hc,
+			f.cfg.PollingInterval,
+			f.logger,
+			true,
+			res),
+		logger:    f.logger,
+		evaluator: engine.NewEvaluator(f.logger),
+	}
 
+	// return res
 }

unlaunchio/service/httpfeaturestore.go

@@ -4,11 +4,12 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
+	"sort"
+	"time"
+
 	"github.com/unlaunch/go-sdk/unlaunchio/dtos"
 	"github.com/unlaunch/go-sdk/unlaunchio/util"
 	"github.com/unlaunch/go-sdk/unlaunchio/util/logger"
-	"sort"
-	"time"
 )
 
 type HTTPFeatureStore struct {
@@ -17,6 +18,8 @@ type HTTPFeatureStore struct {
 	features            map[string]dtos.Feature
 	initialSyncComplete bool
 	shutdownCh          chan bool
+	sync0Complete       bool
+	res                 []byte
 }
 
 func (h *HTTPFeatureStore) Shutdown() {
@@ -25,30 +28,42 @@ func (h *HTTPFeatureStore) Shutdown() {
 }
 
 func (h *HTTPFeatureStore) fetchFlags() error {
-	res, err := h.httpClient.Get("/api/v1/flags")
-
-	if err != nil {
-		if httpError, ok := err.(*dtos.HTTPError); ok {
-			if httpError.Code == 403 {
-				h.logger.Error(
-					fmt.Sprintf("The API key you provided was rejected by the server. %s", util.SDKKeyHelpMessage))
+	var res []byte
+	var err error
+	if !h.sync0Complete {
+		res, err = h.httpClient.Get("/api/v1/flags")
+
+		if err != nil {
+			if httpError, ok := err.(*dtos.HTTPError); ok {
+				if httpError.Code == 403 {
+					h.logger.Error(
+						fmt.Sprintf("The API key you provided was rejected by the server. %s", util.SDKKeyHelpMessage))
+				}
+			} else {
+				h.logger.Error("error fetching flags ", err)
+				return err
 			}
-		} else {
-			h.logger.Error("error fetching flags ", err)
-			return err
 		}
-	}
 
-	if res == nil {
-		// No error and empty response means nothing changed
-		// most like due to 304; not modified
-		return nil
+		if res == nil {
+			// No error and empty response means nothing changed
+			// most like due to 304; not modified
+			return nil
+		}
+
+		h.logger.Trace("responseDto ", string(res))
+
+	} else {
+		res = h.res
 	}
 
-	h.logger.Trace("responseDto ", string(res))
+	return h.initFeatureMap(res)
 
+}
+
+func (h *HTTPFeatureStore) initFeatureMap(res []byte) error {
 	var responseDto dtos.TopLevelEnvelope
-	err = json.Unmarshal(res, &responseDto)
+	err := json.Unmarshal(res, &responseDto)
 
 	if err != nil {
 		h.logger.Error("error parsing feature flag JSON response ", err)
@@ -77,6 +92,7 @@ func (h *HTTPFeatureStore) fetchFlags() error {
 	h.features = temp
 
 	h.logger.Debug("Downloaded: ", len(h.features))
+
 	return nil
 }
 
@@ -115,12 +131,16 @@ func (h *HTTPFeatureStore) Ready(timeout time.Duration) {
 func NewHTTPFeatureStore(
 	httpClient util.HTTPClient,
 	pollingInterval time.Duration,
-	logger logger.Interface) FeatureStore {
+	logger logger.Interface,
+	sync0Complete bool,
+	res []byte) FeatureStore {
 	httpStore := &HTTPFeatureStore{
 		httpClient:          httpClient,
 		logger:              logger,
 		initialSyncComplete: false,
 		features:            nil,
+		sync0Complete:       sync0Complete,
+		res:                 res,
 	}
 
 	httpStore.shutdownCh = util.RunImmediatelyAndSchedule(httpStore.fetchFlags, pollingInterval)

unlaunchio/service/httpfeaturestore_test.go

@@ -75,7 +75,7 @@ func TestWhen_DataIsReturned_Then_FeatureStoreIsReady(t *testing.T) {
 	h := &mockHTTPClient{}
 	h.returnValidJSON = true
 
-	fs := NewHTTPFeatureStore(h, 100000000, logger.NewLogger(nil))
+	fs := NewHTTPFeatureStore(h, 100000000, logger.NewLogger(nil), false, nil)
 
 	time.Sleep(100 * time.Millisecond)
 
@@ -89,7 +89,7 @@ func getHTTPFeatureStore() FeatureStore {
 	h := NewHTTPFeatureStore(
 		&mockHTTPClient{},
 		900,
-		logger.NewLogger(nil))
+		logger.NewLogger(nil), false, nil)
 	return h
 }
 

unlaunchio/util/httpclient.go

@@ -3,11 +3,12 @@ package util
 import (
 	"bytes"
 	"fmt"
-	"github.com/unlaunch/go-sdk/unlaunchio/dtos"
-	"github.com/unlaunch/go-sdk/unlaunchio/util/logger"
 	"io/ioutil"
 	"net/http"
 	"time"
+
+	"github.com/unlaunch/go-sdk/unlaunchio/dtos"
+	"github.com/unlaunch/go-sdk/unlaunchio/util/logger"
 )
 
 type HTTPClient interface {
@@ -24,23 +25,45 @@ type simpleHTTPClient struct {
 	lastModifiedAt string
 }
 
+type GenericHTTPClient struct {
+	host       string
+	httpClient *http.Client
+	logger     logger.Interface
+	sdkKey     string
+}
+
 // NewHTTPClient returns a new http client
 func NewHTTPClient(
 	sdkKey string,
 	host string,
 	timeout time.Duration,
 	logger logger.Interface,
+	sync0 bool,
 ) HTTPClient {
 
-	client := &http.Client{
-		Timeout: timeout,
-	}
+	if sync0 {
+		client := &http.Client{
+			Timeout: timeout,
+		}
+
+		return &GenericHTTPClient{
+			host:       host,
+			httpClient: client,
+			logger:     logger,
+			sdkKey:     sdkKey,
+		}
+
+	} else {
+		client := &http.Client{
+			Timeout: timeout,
+		}
 
-	return &simpleHTTPClient{
-		host:       host,
-		httpClient: client,
-		logger:     logger,
-		sdkKey:     sdkKey,
+		return &simpleHTTPClient{
+			host:       host,
+			httpClient: client,
+			logger:     logger,
+			sdkKey:     sdkKey,
+		}
 	}
 }
 
@@ -126,3 +149,44 @@ func (c *simpleHTTPClient) Post(path string, body []byte) error {
 		Msg:  resp.Status,
 	}
 }
+
+func (c *GenericHTTPClient) Get(path string) ([]byte, error) {
+	apiEndpoint := path
+	c.logger.Debug("[HTTP GET] ", apiEndpoint)
+
+	req, _ := http.NewRequest("GET", apiEndpoint, nil)
+
+	resp, err := c.httpClient.Do(req)
+
+	if err != nil {
+		c.logger.Error("[HTTP GET] HTTP error ", err)
+		return nil, err
+	}
+
+	defer resp.Body.Close()
+
+	reader := resp.Body
+	defer reader.Close()
+
+	body, err := ioutil.ReadAll(reader)
+
+	if err != nil {
+		c.logger.Error("[HTTP GET] error reading body", err)
+		return nil, err
+	}
+
+	c.logger.Debug(fmt.Sprintf("[HTTP GET] status code: %d", resp.StatusCode))
+
+	if resp.StatusCode >= 200 && resp.StatusCode < 300 {
+		return body, nil
+	} else {
+		return nil, &dtos.HTTPError{
+			Code: resp.StatusCode,
+			Msg:  resp.Status,
+		}
+	}
+}
+
+func (c *GenericHTTPClient) Post(path string, body []byte) error {
+	return nil
+}