cmd/pkgserver: search endpoint

cmd/pkgserver/api.go

@@ -4,6 +4,7 @@ import (
 	"encoding/json"
 	"log"
 	"net/http"
+	"net/url"
 	"path"
 	"strconv"
 	"sync"
@@ -104,9 +105,46 @@ func (index *packageIndex) handleGet(w http.ResponseWriter, r *http.Request) {
 	values := index.sorts[sort][i:min(i+limit, len(index.sorts[sort]))]
 	// TODO(mae): remove count field
 	writeAPIPayload(w, &struct {
-		Count  int         `json:"count"`
 		Values []*metadata `json:"values"`
-	}{len(values), values})
+	}{values})
+}
+
+func (index *packageIndex) handleSearch(w http.ResponseWriter, r *http.Request) {
+	q := r.URL.Query()
+	limit, err := strconv.Atoi(q.Get("limit"))
+	if err != nil || limit > 100 || limit < 1 {
+		http.Error(
+			w, "limit must be an integer between 1 and 100",
+			http.StatusBadRequest,
+		)
+		return
+	}
+	i, err := strconv.Atoi(q.Get("index"))
+	if err != nil || i >= len(index.sorts[0]) || i < 0 {
+		http.Error(
+			w, "index must be an integer between 0 and "+
+				strconv.Itoa(int(rosa.PresetUnexportedStart-1)),
+			http.StatusBadRequest,
+		)
+		return
+	}
+	search, err := url.PathUnescape(q.Get("search"))
+	if len(search) > 100 || err != nil {
+		http.Error(
+			w, "search must be a string between 0 and 100 characters long",
+			http.StatusBadRequest,
+		)
+		return
+	}
+	desc := q.Get("desc") == "true"
+	n, res, err := index.performSearchQuery(limit, i, search, desc)
+	if err != nil {
+		http.Error(w, err.Error(), http.StatusInternalServerError)
+	}
+	writeAPIPayload(w, &struct {
+		Count   int            `json:"count"`
+		Results []searchResult `json:"results"`
+	}{n, res})
 }
 
 // apiVersion is the name of the current API revision, as part of the pattern.
@@ -116,6 +154,7 @@ const apiVersion = "v1"
 func (index *packageIndex) registerAPI(mux *http.ServeMux) {
 	mux.HandleFunc("GET /api/"+apiVersion+"/info", handleInfo)
 	mux.HandleFunc("GET /api/"+apiVersion+"/get", index.handleGet)
+	mux.HandleFunc("GET /api/"+apiVersion+"/search", index.handleSearch)
 	mux.HandleFunc("GET /api/"+apiVersion+"/status/", index.newStatusHandler(false))
 	mux.HandleFunc("GET /status/", index.newStatusHandler(true))
 }

cmd/pkgserver/index.go

@@ -23,9 +23,9 @@ const (
 
 // packageIndex refers to metadata by name and various sort orders.
 type packageIndex struct {
-	sorts [sortOrderEnd + 1][rosa.PresetUnexportedStart]*metadata
-	names map[string]*metadata
-
+	sorts  [sortOrderEnd + 1][rosa.PresetUnexportedStart]*metadata
+	names  map[string]*metadata
+	search searchCache
 	// Taken from [rosa.Report] if available.
 	handleAccess func(*error) func()
 }

cmd/pkgserver/main.go

@@ -64,10 +64,22 @@ func main() {
 		}
 
 		var index packageIndex
+		index.search = make(searchCache)
 		if err := index.populate(cache, report); err != nil {
 			return err
 		}
-
+		ticker := time.NewTicker(1 * time.Minute)
+		go func() {
+			for {
+				select {
+				case <-ctx.Done():
+					ticker.Stop()
+					return
+				case <-ticker.C:
+					index.search.clean()
+				}
+			}
+		}()
 		var mux http.ServeMux
 		uiRoutes(&mux)
 		index.registerAPI(&mux)

cmd/pkgserver/search.go

@@ -0,0 +1,77 @@
+package main
+
+import (
+	"cmp"
+	"maps"
+	"regexp"
+	"slices"
+	"time"
+)
+
+type searchCache map[string]searchCacheEntry
+type searchResult struct {
+	NameIndices [][]int `json:"name_matches"`
+	DescIndices [][]int `json:"desc_matches,omitempty"`
+	Score       float64 `json:"score"`
+	*metadata
+}
+type searchCacheEntry struct {
+	query   string
+	results []searchResult
+	expiry  time.Time
+}
+
+func (index *packageIndex) performSearchQuery(limit int, i int, search string, desc bool) (int, []searchResult, error) {
+	entry, ok := index.search[search]
+	if ok {
+		return len(entry.results), entry.results[i:min(i+limit, len(entry.results))], nil
+	}
+
+	regex, err := regexp.Compile(search)
+	if err != nil {
+		return 0, make([]searchResult, 0), err
+	}
+	res := make([]searchResult, 0)
+	for p := range maps.Values(index.names) {
+		nameIndices := regex.FindAllIndex([]byte(p.Name), -1)
+		var descIndices [][]int = nil
+		if desc {
+			descIndices = regex.FindAllIndex([]byte(p.Description), -1)
+		}
+		if nameIndices == nil && descIndices == nil {
+			continue
+		}
+		score := float64(indexsum(nameIndices)) / (float64(len(nameIndices)) + 1)
+		if desc {
+			score += float64(indexsum(descIndices)) / (float64(len(descIndices)) + 1) / 10.0
+		}
+		res = append(res, searchResult{
+			NameIndices: nameIndices,
+			DescIndices: descIndices,
+			Score:       score,
+			metadata:    p,
+		})
+	}
+	slices.SortFunc(res[:], func(a, b searchResult) int { return -cmp.Compare(a.Score, b.Score) })
+	expiry := time.Now().Add(1 * time.Minute)
+	entry = searchCacheEntry{
+		query:   search,
+		results: res,
+		expiry:  expiry,
+	}
+	index.search[search] = entry
+
+	return len(res), res[i:min(i+limit, len(entry.results))], nil
+}
+func (s *searchCache) clean() {
+	maps.DeleteFunc(*s, func(_ string, v searchCacheEntry) bool {
+		return v.expiry.Before(time.Now())
+	})
+}
+func indexsum(in [][]int) int {
+	sum := 0
+	for i := 0; i < len(in); i++ {
+		sum += in[i][1] - in[i][0]
+	}
+	return sum
+}

cmd/pkgserver/ui.go

@@ -21,13 +21,10 @@ func serveStaticContent(w http.ResponseWriter, r *http.Request) {
 		} else {
 			http.ServeFileFS(w, r, content, "ui/static/light.css")
 		}
-		break
 	case "/favicon.ico":
 		http.ServeFileFS(w, r, content, "ui/static/favicon.ico")
-		break
 	case "/static/index.js":
 		http.ServeFileFS(w, r, content, "ui/static/index.js")
-		break
 	default:
 		http.NotFound(w, r)