dashboard/app: add handler to wipe a builder's results column

Change-Id: Idc3284ff8564a8863d8352890e285babded362cf
Reviewed-on: https://go-review.googlesource.com/1539
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

dashboard/app/app.yaml

@@ -13,7 +13,7 @@ handlers:
   static_dir: static
 - url: /(|gccgo/|hg/)log/.+
   script: _go_app
-- url: /(|gccgo/|hg/)(|commit|packages|result|perf-result|tag|todo|perf|perfdetail|perfgraph|updatebenchmark)
+- url: /(|gccgo/|hg/)(|clear-results|commit|packages|result|perf-result|tag|todo|perf|perfdetail|perfgraph|updatebenchmark)
   script: _go_app
 - url: /(|gccgo/|hg/)(init|buildtest|key|perflearn|_ah/queue/go/delay)
   script: _go_app

dashboard/app/build/build.go

@@ -145,7 +145,7 @@ func putCommit(c appengine.Context, com *Commit) error {
 // build history and the AppEngine datastore limit of 1mb.
 const maxResults = 1000
 
-// AddResult adds the denormalized Result data to the Commit's Result field.
+// AddResult adds the denormalized Result data to the Commit's ResultData field.
 // It must be called from inside a datastore transaction.
 func (com *Commit) AddResult(c appengine.Context, r *Result) error {
 	if err := datastore.Get(c, com.Key(c), com); err != nil {
@@ -167,6 +167,21 @@ func (com *Commit) AddResult(c appengine.Context, r *Result) error {
 	return putCommit(c, com)
 }
 
+// removeResult removes the denormalized Result data from the ResultData field
+// for the given builder and go hash.
+// It must be called from within the datastore transaction that gets and puts
+// the Commit. Note this is slightly different to AddResult, above.
+func (com *Commit) RemoveResult(r *Result) {
+	var rd []string
+	for _, s := range com.ResultData {
+		if strings.HasPrefix(s, r.Builder+"|") && strings.HasSuffix(s, "|"+r.GoHash) {
+			continue
+		}
+		rd = append(rd, s)
+	}
+	com.ResultData = rd
+}
+
 // AddPerfResult remembers that the builder has run the benchmark on the commit.
 // It must be called from inside a datastore transaction.
 func (com *Commit) AddPerfResult(c appengine.Context, builder, benchmark string) error {
@@ -205,7 +220,7 @@ func (c *Commit) Result(builder, goHash string) *Result {
 		if len(p) != 4 || p[0] != builder || p[3] != goHash {
 			continue
 		}
-		return partsToHash(c, p)
+		return partsToResult(c, p)
 	}
 	return nil
 }
@@ -217,7 +232,7 @@ func (c *Commit) Results() (results []*Result) {
 		if len(p) != 4 {
 			continue
 		}
-		results = append(results, partsToHash(c, p))
+		results = append(results, partsToResult(c, p))
 	}
 	return
 }
@@ -371,8 +386,8 @@ func GetCommits(c appengine.Context, startCommitNum, n int) ([]*Commit, error) {
 	return res, nil
 }
 
-// partsToHash converts a Commit and ResultData substrings to a Result.
-func partsToHash(c *Commit, p []string) *Result {
+// partsToResult converts a Commit and ResultData substrings to a Result.
+func partsToResult(c *Commit, p []string) *Result {
 	return &Result{
 		Builder:     p[0],
 		Hash:        c.Hash,

dashboard/app/build/handler.go

@@ -793,6 +793,53 @@ func logHandler(w http.ResponseWriter, r *http.Request) {
 	w.Write(b)
 }
 
+// clearResultsHandler purges the last commitsPerPage results for the given builder.
+// It optionally takes a comma-separated list of specific hashes to clear.
+func clearResultsHandler(r *http.Request) (interface{}, error) {
+	if r.Method != "POST" {
+		return nil, errBadMethod(r.Method)
+	}
+	builder := r.FormValue("builder")
+	if builder == "" {
+		return nil, errors.New("must specify a builder")
+	}
+	clearAll := r.FormValue("hash") == ""
+	hash := strings.Split(r.FormValue("hash"), ",")
+
+	c := contextForRequest(r)
+	defer cache.Tick(c)
+	pkg := (&Package{}).Key(c) // TODO(adg): support clearing sub-repos
+	err := datastore.RunInTransaction(c, func(c appengine.Context) error {
+		var coms []*Commit
+		keys, err := datastore.NewQuery("Commit").
+			Ancestor(pkg).
+			Order("-Num").
+			Limit(commitsPerPage).
+			GetAll(c, &coms)
+		if err != nil {
+			return err
+		}
+		var rKeys []*datastore.Key
+		for _, com := range coms {
+			if !(clearAll || contains(hash, com.Hash)) {
+				continue
+			}
+			r := com.Result(builder, "")
+			if r == nil {
+				continue
+			}
+			com.RemoveResult(r)
+			rKeys = append(rKeys, r.Key(c))
+		}
+		_, err = datastore.PutMulti(c, keys, coms)
+		if err != nil {
+			return err
+		}
+		return datastore.DeleteMulti(c, rKeys)
+	}, nil)
+	return nil, err
+}
+
 type dashHandler func(*http.Request) (interface{}, error)
 
 type dashResponse struct {
@@ -862,10 +909,11 @@ func init() {
 	handleFunc("/key", keyHandler)
 
 	// authenticated handlers
+	handleFunc("/clear-results", AuthHandler(clearResultsHandler))
 	handleFunc("/commit", AuthHandler(commitHandler))
 	handleFunc("/packages", AuthHandler(packagesHandler))
-	handleFunc("/result", AuthHandler(resultHandler))
 	handleFunc("/perf-result", AuthHandler(perfResultHandler))
+	handleFunc("/result", AuthHandler(resultHandler))
 	handleFunc("/tag", AuthHandler(tagHandler))
 	handleFunc("/todo", AuthHandler(todoHandler))