From 9e726028c31865560b85a5ac38e4d673253c125d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ferdinand=20M=C3=BCtsch?= <mail@ferdinand-muetsch.de>
Date: Thu, 7 Nov 2019 12:56:05 +0100
Subject: [PATCH] Introduce flag to recompute summaries from raw events instead
 of using aggregations.

---
 main.go                 |  7 +------
 routes/summary.go       | 13 ++++++++++---
 services/aggregation.go |  2 +-
 services/summary.go     | 14 ++++++++++----
 4 files changed, 22 insertions(+), 14 deletions(-)

diff --git a/main.go b/main.go
index f2d9e44..477a505 100644
--- a/main.go
+++ b/main.go
@@ -170,12 +170,7 @@ func migrateLanguages(db *gorm.DB, cfg *models.Config) {
 func addDefaultUser(db *gorm.DB, cfg *models.Config) {
 	pw := md5.Sum([]byte(models.DefaultPassword))
 	pwString := hex.EncodeToString(pw[:])
-	var err error
-	apiKey := uuid.Must(uuid.NewV4(), err).String()
-	if err != nil {
-		log.Println("Unable to create api key.")
-		log.Fatal(err)
-	}
+	apiKey := uuid.NewV4().String()
 	u := &models.User{ID: models.DefaultUser, Password: pwString, ApiKey: apiKey}
 	result := db.FirstOrCreate(u, &models.User{ID: u.ID})
 	if result.Error != nil {
diff --git a/routes/summary.go b/routes/summary.go
index 651236d..b120d41 100644
--- a/routes/summary.go
+++ b/routes/summary.go
@@ -10,6 +10,7 @@ import (
 	"github.com/n1try/wakapi/services"
 	"github.com/n1try/wakapi/utils"
 	cache "github.com/patrickmn/go-cache"
+	uuid "github.com/satori/go.uuid"
 )
 
 const (
@@ -67,21 +68,27 @@ func (h *SummaryHandler) Get(w http.ResponseWriter, r *http.Request) {
 	}
 
 	live := (params.Get("live") != "" && params.Get("live") != "false") || interval == IntervalToday
+	recompute := (params.Get("recompute") != "" && params.Get("recompute") != "false")
 	to := utils.StartOfDay()
 	if live {
 		to = time.Now()
 	}
 
 	var summary *models.Summary
-	cacheKey := getHash([]time.Time{from, to}, user)
+	var cacheKey string
+	if !recompute {
+		cacheKey = getHash([]time.Time{from, to}, user)
+	} else {
+		cacheKey = uuid.NewV4().String()
+	}
 	if cachedSummary, ok := h.Cache.Get(cacheKey); !ok {
 		// Cache Miss
-		summary, err = h.SummarySrvc.Construct(from, to, user) // 'to' is always constant
+		summary, err = h.SummarySrvc.Construct(from, to, user, recompute) // 'to' is always constant
 		if err != nil {
 			w.WriteHeader(http.StatusInternalServerError)
 			return
 		}
-		if !live {
+		if !live && !recompute {
 			h.Cache.Set(cacheKey, summary, cache.DefaultExpiration)
 		}
 	} else {
diff --git a/services/aggregation.go b/services/aggregation.go
index 9158127..e834507 100644
--- a/services/aggregation.go
+++ b/services/aggregation.go
@@ -53,7 +53,7 @@ func (srv *AggregationService) Schedule() {
 
 func (srv *AggregationService) summaryWorker(jobs <-chan *AggregationJob, summaries chan<- *models.Summary) {
 	for job := range jobs {
-		if summary, err := srv.SummaryService.Construct(job.From, job.To, &models.User{ID: job.UserID}); err != nil {
+		if summary, err := srv.SummaryService.Construct(job.From, job.To, &models.User{ID: job.UserID}, true); err != nil {
 			log.Printf("Failed to generate summary (%v, %v, %s) – %v.\n", job.From, job.To, job.UserID, err)
 		} else {
 			log.Printf("Successfully generated summary (%v, %v, %s).\n", job.From, job.To, job.UserID)
diff --git a/services/summary.go b/services/summary.go
index 91c8db4..ca809f8 100644
--- a/services/summary.go
+++ b/services/summary.go
@@ -22,10 +22,16 @@ type Interval struct {
 	End   time.Time
 }
 
-func (srv *SummaryService) Construct(from, to time.Time, user *models.User) (*models.Summary, error) {
-	existingSummaries, err := srv.GetByUserWithin(user, from, to)
-	if err != nil {
-		return nil, err
+func (srv *SummaryService) Construct(from, to time.Time, user *models.User, recompute bool) (*models.Summary, error) {
+	var existingSummaries []*models.Summary
+	if recompute {
+		existingSummaries = make([]*models.Summary, 0)
+	} else {
+		summaries, err := srv.GetByUserWithin(user, from, to)
+		if err != nil {
+			return nil, err
+		}
+		existingSummaries = summaries
 	}
 
 	missingIntervals := getMissingIntervals(from, to, existingSummaries)