Added 60 seconds caching to navitia api departures requests

4 files changed, 35 insertions, 1 deletions

diff --git a/navitia_api_client/client.go b/navitia_api_client/client.go
index d08ca19..aef8d0e 100644
--- a/navitia_api_client/client.go
+++ b/navitia_api_client/client.go
@@ -3,12 +3,21 @@ package navitia_api_client
 import (
 	"fmt"
 	"net/http"
+	"sync"
 	"time"
 )
 
 type Client struct {
 	baseURL    string
 	httpClient *http.Client
+
+	mutex sync.Mutex
+	cache map[string]cachedResult
+}
+
+type cachedResult struct {
+	ts     time.Time
+	result interface{}
 }
 
 func NewClient(token string) *Client {
@@ -17,5 +26,6 @@ func NewClient(token string) *Client {
 		httpClient: &http.Client{
 			Timeout: time.Minute,
 		},
+		cache: make(map[string]cachedResult),
 	}
 }
diff --git a/navitia_api_client/client_test.go b/navitia_api_client/client_test.go
index ec51a06..332b222 100644
--- a/navitia_api_client/client_test.go
+++ b/navitia_api_client/client_test.go
@@ -13,6 +13,7 @@ func NewTestClient(ts *httptest.Server) *Client {
 	return &Client{
 		baseURL:    fmt.Sprintf(ts.URL),
 		httpClient: ts.Client(),
+		cache:      make(map[string]cachedResult),
 	}
 }
 
diff --git a/navitia_api_client/departures.go b/navitia_api_client/departures.go
index a6dcf53..7738940 100644
--- a/navitia_api_client/departures.go
+++ b/navitia_api_client/departures.go
@@ -4,6 +4,7 @@ import (
 	"encoding/json"
 	"fmt"
 	"net/http"
+	"time"
 )
 
 type DeparturesResponse struct {
@@ -43,7 +44,16 @@ type DeparturesResponse struct {
 }
 
 func (c *Client) GetDepartures() (departures *DeparturesResponse, err error) {
-	req, err := http.NewRequest("GET", fmt.Sprintf("%s/coverage/sncf/stop_areas/stop_area:SNCF:87723502/departures", c.baseURL), nil)
+	request := fmt.Sprintf("%s/coverage/sncf/stop_areas/stop_area:SNCF:87723502/departures", c.baseURL)
+	start := time.Now()
+	c.mutex.Lock()
+	defer c.mutex.Unlock()
+	if cachedResult, ok := c.cache[request]; ok {
+		if start.Sub(cachedResult.ts) < 60*1000*1000*1000 {
+			return cachedResult.result.(*DeparturesResponse), nil
+		}
+	}
+	req, err := http.NewRequest("GET", request, nil)
 	if err != nil {
 		return nil, err
 	}
@@ -55,5 +65,9 @@ func (c *Client) GetDepartures() (departures *DeparturesResponse, err error) {
 	if err = json.NewDecoder(resp.Body).Decode(&departures); err != nil {
 		return nil, err
 	}
+	c.cache[request] = cachedResult{
+		ts:     start,
+		result: departures,
+	}
 	return
 }
diff --git a/navitia_api_client/departures_test.go b/navitia_api_client/departures_test.go
index 2c87429..a1658d2 100644
--- a/navitia_api_client/departures_test.go
+++ b/navitia_api_client/departures_test.go
@@ -45,4 +45,13 @@ func TestGetDepartures(t *testing.T) {
 	if len(departures.Departures) != 10 {
 		t.Fatalf("did not decode normal-crepieux departures properly, got %d departures when expected 10", len(departures.Departures))
 	}
+	// test the cache (assuming the test takes less than 60 seconds (and it really should) it will be accurate)
+	ts.Close()
+	departures, err = client.GetDepartures()
+	if err != nil {
+		t.Fatalf("could not get normal-crepieux departures : %s", err)
+	}
+	if len(departures.Departures) != 10 {
+		t.Fatalf("did not decode normal-crepieux departures properly, got %d departures when expected 10", len(departures.Departures))
+	}
 }