entur: Implement client for new API

4 files changed, 283 insertions, 0 deletions

diff --git a/.gitattributes b/.gitattributes
new file mode 100644
index 0000000..6767a69
--- /dev/null
+++ b/.gitattributes
@@ -0,0 +1 @@
+**/testdata/* linguist-vendored
diff --git a/entur/entur.go b/entur/entur.go
new file mode 100644
index 0000000..4dfc60b
--- /dev/null
+++ b/entur/entur.go
@@ -0,0 +1,131 @@
+package entur
+
+import (
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
+	"net/http"
+	"strings"
+	"time"
+)
+
+// DefaultURL is the default Entur Journey Planner API URL. Documentation at
+// https://developer.entur.org/pages-journeyplanner-journeyplanner-v2.
+const DefaultURL = "https://api.entur.io/journey-planner/v2/graphql"
+
+// Client implements a client for the Entur Journey Planner API.
+type Client struct{ URL string }
+
+// New creates a new client using the API found at url.
+func New(url string) *Client {
+	if url == "" {
+		url = DefaultURL
+	}
+	return &Client{URL: url}
+}
+
+// Departure represents a bus departure from a stop.
+type Departure struct {
+	Line                    string
+	RegisteredDepartureTime time.Time
+	ScheduledDepartureTime  time.Time
+	Destination             string
+	IsRealtime              bool
+	Inbound                 bool
+}
+
+type response struct {
+	Data data `json:"data"`
+}
+
+type data struct {
+	StopPlace stopPlace `json:"stopPlace"`
+}
+
+type stopPlace struct {
+	ID             string          `json:"id"`
+	Name           string          `json:"name"`
+	EstimatedCalls []estimatedCall `json:"estimatedCalls"`
+}
+
+type estimatedCall struct {
+	Realtime              bool               `json:"realtime"`
+	ExpectedDepartureTime string             `json:"expectedDepartureTime"`
+	ActualDepartureTime   string             `json:"actualDepartureTime"`
+	DestinationDisplay    destinationDisplay `json:"destinationDisplay"`
+	ServiceJourney        serviceJourney     `json:"serviceJourney"`
+}
+
+type destinationDisplay struct {
+	FrontText string `json:"frontText"`
+}
+
+type serviceJourney struct {
+	JourneyPattern journeyPattern `json:"journeyPattern"`
+}
+
+type journeyPattern struct {
+	DirectionType string `json:"directionType"`
+	Line          line   `json:"line"`
+}
+
+type line struct {
+	PublicCode string `json:"publicCode"`
+}
+
+// Departures returns departures from the given stop ID. Use https://stoppested.entur.org/ to determine stop IDs.
+func (c *Client) Departures(stopID int) ([]Departure, error) {
+	// https://api.entur.io/journey-planner/v2/ide/ for query testing
+	query := fmt.Sprintf(`{"query":"{stopPlace(id:\"NSR:StopPlace:%d\"){id name estimatedCalls{realtime expectedDepartureTime actualDepartureTime destinationDisplay{frontText}serviceJourney{journeyPattern{directionType line{publicCode}}}}}}"}`, stopID)
+	req, err := http.NewRequest("POST", c.URL, strings.NewReader(query))
+	if err != nil {
+		return nil, err
+	}
+	req.Header.Set("Content-Type", "application/json")
+	// Identify this client. See https://developer.entur.org/pages-journeyplanner-journeyplanner-v2
+	req.Header.Set("ET-Client-Name", "github_mpolden-atb")
+	resp, err := http.DefaultClient.Do(req)
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Body.Close()
+	json, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		return nil, err
+	}
+	return parseDepartures(json)
+}
+
+func parseDepartures(jsonData []byte) ([]Departure, error) {
+	var r response
+	if err := json.Unmarshal(jsonData, &r); err != nil {
+		return nil, err
+	}
+	const timeLayout = "2006-01-02T15:04:05-0700"
+	departures := make([]Departure, 0, len(r.Data.StopPlace.EstimatedCalls))
+	for _, ec := range r.Data.StopPlace.EstimatedCalls {
+		scheduledDepartureTime, err := time.Parse(timeLayout, ec.ExpectedDepartureTime)
+		if err != nil {
+			return nil, err
+		}
+		registeredDepartureTime := time.Time{}
+		if ec.ActualDepartureTime != "" {
+			t, err := time.Parse(timeLayout, ec.ActualDepartureTime)
+			if err != nil {
+				return nil, err
+			}
+			registeredDepartureTime = t
+		}
+		inbound := ec.ServiceJourney.JourneyPattern.DirectionType == "inbound"
+		d := Departure{
+			Line:                    ec.ServiceJourney.JourneyPattern.Line.PublicCode,
+			RegisteredDepartureTime: registeredDepartureTime,
+			ScheduledDepartureTime:  scheduledDepartureTime,
+			Destination:             ec.DestinationDisplay.FrontText,
+			IsRealtime:              ec.Realtime,
+			Inbound:                 inbound,
+		}
+		departures = append(departures, d)
+	}
+	return departures, nil
+}
diff --git a/entur/entur_test.go b/entur/entur_test.go
new file mode 100644
index 0000000..dd98ea1
--- /dev/null
+++ b/entur/entur_test.go
@@ -0,0 +1,61 @@
+package entur
+
+import (
+	"io/ioutil"
+	"path/filepath"
+	"testing"
+	"time"
+)
+
+func TestParseDepartures(t *testing.T) {
+	testFile := filepath.Join("testdata", "ilsvika.json")
+	json, err := ioutil.ReadFile(testFile)
+	if err != nil {
+		t.Fatal(err)
+	}
+	d, err := parseDepartures(json)
+	if err != nil {
+		t.Fatal(err)
+	}
+	cest := time.FixedZone("CEST", 7200)
+	expected := []Departure{
+		{
+			Line:                    "21",
+			RegisteredDepartureTime: time.Time{},
+			ScheduledDepartureTime:  time.Date(2021, 8, 11, 21, 19, 0, 0, cest),
+			Destination:             "Pirbadet via sentrum",
+			IsRealtime:              false,
+			Inbound:                 false,
+		},
+		{
+			Line:                    "21",
+			RegisteredDepartureTime: time.Time{},
+			ScheduledDepartureTime:  time.Date(2021, 8, 11, 22, 19, 0, 0, cest),
+			Destination:             "Pirbadet via sentrum",
+			IsRealtime:              true,
+			Inbound:                 false,
+		},
+	}
+	for i := 0; i < len(expected); i++ {
+		got := d[i]
+		want := expected[i]
+		if want.Line != got.Line {
+			t.Errorf("#%d: want Line = %q, got %q", i, want.Line, got.Line)
+		}
+		if !want.RegisteredDepartureTime.Equal(got.RegisteredDepartureTime) {
+			t.Errorf("#%d: want RegisteredDepartureTime = %q, got %q", i, want.RegisteredDepartureTime, got.RegisteredDepartureTime)
+		}
+		if !want.ScheduledDepartureTime.Equal(got.ScheduledDepartureTime) {
+			t.Errorf("#%d: want ScheduledDepartureTime = %q, got %q", i, want.ScheduledDepartureTime, got.ScheduledDepartureTime)
+		}
+		if want.Destination != got.Destination {
+			t.Errorf("#%d: want Destination = %q, got %q", i, want.Destination, got.Destination)
+		}
+		if want.IsRealtime != got.IsRealtime {
+			t.Errorf("#%d: want IsRealtime = %t, got %t", i, want.IsRealtime, got.IsRealtime)
+		}
+		if want.Inbound != got.Inbound {
+			t.Errorf("#%d: want Inbound = %t, got %t", i, want.Inbound, got.Inbound)
+		}
+	}
+}
diff --git a/entur/testdata/ilsvika.json b/entur/testdata/ilsvika.json
new file mode 100644
index 0000000..2d6c32f
--- /dev/null
+++ b/entur/testdata/ilsvika.json
@@ -0,0 +1,90 @@
+{
+  "data": {
+    "stopPlace": {
+      "id": "NSR:StopPlace:42098",
+      "name": "Ilsvika",
+      "estimatedCalls": [
+        {
+          "realtime": false,
+          "expectedDepartureTime": "2021-08-11T21:19:00+0200",
+          "actualDepartureTime": null,
+          "destinationDisplay": {
+            "frontText": "Pirbadet via sentrum"
+          },
+          "serviceJourney": {
+            "journeyPattern": {
+              "directionType": "outbound",
+              "line": {
+                "publicCode": "21"
+              }
+            }
+          }
+        },
+        {
+          "realtime": true,
+          "expectedDepartureTime": "2021-08-11T22:19:00+0200",
+          "actualDepartureTime": null,
+          "destinationDisplay": {
+            "frontText": "Pirbadet via sentrum"
+          },
+          "serviceJourney": {
+            "journeyPattern": {
+              "directionType": "outbound",
+              "line": {
+                "publicCode": "21"
+              }
+            }
+          }
+        },
+        {
+          "realtime": false,
+          "expectedDepartureTime": "2021-08-11T23:19:00+0200",
+          "actualDepartureTime": null,
+          "destinationDisplay": {
+            "frontText": "Pirbadet via sentrum"
+          },
+          "serviceJourney": {
+            "journeyPattern": {
+              "directionType": "outbound",
+              "line": {
+                "publicCode": "21"
+              }
+            }
+          }
+        },
+        {
+          "realtime": false,
+          "expectedDepartureTime": "2021-08-12T00:19:00+0200",
+          "actualDepartureTime": null,
+          "destinationDisplay": {
+            "frontText": "Pirbadet via sentrum"
+          },
+          "serviceJourney": {
+            "journeyPattern": {
+              "directionType": "outbound",
+              "line": {
+                "publicCode": "21"
+              }
+            }
+          }
+        },
+        {
+          "realtime": false,
+          "expectedDepartureTime": "2021-08-12T06:13:00+0200",
+          "actualDepartureTime": null,
+          "destinationDisplay": {
+            "frontText": "Pirbadet via sentrum"
+          },
+          "serviceJourney": {
+            "journeyPattern": {
+              "directionType": "outbound",
+              "line": {
+                "publicCode": "21"
+              }
+            }
+          }
+        }
+      ]
+    }
+  }
+}
\ No newline at end of file