Add a function to build the Query Params

Author: fagossa

Diff for: Makefile

@@ -11,5 +11,8 @@ build:
 		-X ${PROJECT}/internal/version.BuildTime=${BUILD_TIME}" \
 		-o bin/server ${PROJECT}/cmd/api
 
+test:
+	GO111MODULE=on go test ./... -v
+
 run:
 		PORT=8080 DIAG_PORT=8081 ./bin/server

Diff for: internal/controllers/utils.go

@@ -2,7 +2,9 @@ package controllers
 
 import (
 	"encoding/json"
+	"fmt"
 	"net/http"
+	"strings"
 )
 
 func getJson(url string, target interface{}) error {
@@ -14,3 +16,16 @@ func getJson(url string, target interface{}) error {
 
 	return json.NewDecoder(r.Body).Decode(target)
 }
+
+func buildQueryParams(prefix string, params map[string][]string) string {
+	var b strings.Builder
+	b.WriteString(prefix)
+
+	for k, v := range params {
+		for _, element := range v {
+			b.WriteString(fmt.Sprintf("%s=%s&", k, element))
+		}
+	}
+
+	return strings.TrimSuffix(b.String(), "&")
+}

Diff for: internal/controllers/utils_test.go

@@ -0,0 +1,21 @@
+package controllers
+
+import (
+	"testing"
+)
+
+func TestBuildQueryUrl(t *testing.T) {
+	queryParams := map[string][]string{
+		"dataset":            []string{"velib-disponibilite-en-temps-reel"},
+		"facet":              []string{"overflowactivation", "creditcard", "kioskstate", "station_state"},
+		"geofilter.distance": []string{"1,2,3"},
+	}
+
+	response := buildQueryParams("?", queryParams)
+
+	expected := "?dataset=velib-disponibilite-en-temps-reel&facet=overflowactivation&facet=creditcard&facet=kioskstate&facet=station_state&geofilter.distance=1,2,3"
+
+	if response != expected {
+		t.Errorf("Query build was incorrect, got: %s, want: %s.", response, expected)
+	}
+}

Diff for: internal/controllers/velibs.go

@@ -15,17 +15,23 @@ func ReadVelib() http.HandlerFunc {
 	long := "2.402782"
 	radius := "100"
 
+	queryParams := map[string][]string{
+		"dataset":            []string{"velib-disponibilite-en-temps-reel"},
+		"facet":              []string{"overflowactivation", "creditcard", "kioskstate", "station_state"},
+		"geofilter.distance": []string{fmt.Sprintf("%s,%s,%s", lat, long, radius)},
+	}
+
 	return func(w http.ResponseWriter, r *http.Request) {
 		route := "https://opendata.paris.fr/api/records/1.0/search"
 
-		// Assemblage route + query string avec encodage des caractères spéciaux
-		params := fmt.Sprintf("?dataset=velib-disponibilite-en-temps-reel&facet=overflowactivation&facet=creditcard&facet=kioskstate&facet=station_state&geofilter.distance=%s,%s,%s",
-			lat, long, radius)
-		url := fmt.Sprintf("%s/%s", route, html.EscapeString(params))
+		queryParams := buildQueryParams("?", queryParams)
+
+		url := fmt.Sprintf("%s/%s", route, html.EscapeString(queryParams))
 
 		payload := models.VelibStatus{}
 		err := getJson(url, &payload)
 		if err != nil {
+			log.Warn("Error reading velib status")
 			http.Error(w, err.Error(), http.StatusBadRequest)
 			return
 		}