twitch: add Get Streams

twitch/streams.go

@@ -0,0 +1,60 @@
+package twitch
+
+import (
+	"context"
+	"fmt"
+	"net/url"
+	"time"
+)
+
+// Stream is the response type from https://dev.twitch.tv/docs/api/reference/#get-streams.
+type Stream struct {
+	ID           string    `json:"id"`
+	UserID       string    `json:"user_id"`
+	UserLogin    string    `json:"user_login"`
+	UserName     string    `json:"user_name"`
+	GameID       string    `json:"game_id"`
+	GameName     string    `json:"game_name"`
+	Type         string    `json:"type"`
+	Title        string    `json:"title"`
+	Tags         []string  `json:"tags"`
+	ViewerCount  int       `json:"viewer_count"`
+	StartedAt    time.Time `json:"started_at"`
+	Language     string    `json:"language"`
+	ThumbnailURL string    `json:"thumbnail_url"`
+	IsMature     bool      `json:"is_mature"`
+	// tag_ids is deprecated and always empty
+}
+
+// UserStreams gets stream information for a list of up to 100 users.
+// For each stream in the given list, if the user ID is provided, then the
+// query is made by user ID, and otherwise it is made by user login.
+// (NOTE: the ID field is not used as input; only UserID.)
+// Logins used to search are normalized to lower case.
+// The result reuses the memory in streams, but may be of different length and
+// in any order.
+//
+// If a given stream has both an ID and a login, the ID is used and the login
+// is replaced with the result from the API.
+// If a stream has neither, it is ignored.
+func UserStreams(ctx context.Context, client Client, streams []Stream) ([]Stream, error) {
+	v := url.Values{
+		"user_id":    nil,
+		"user_login": nil,
+	}
+	for _, s := range streams {
+		if s.UserID != "" {
+			v["user_id"] = append(v["user_id"], s.UserID)
+			continue
+		}
+		if s.UserLogin != "" {
+			v["user_login"] = append(v["user_login"], s.UserLogin)
+		}
+	}
+	url := apiurl("/helix/streams", v)
+	err := reqjson(ctx, client, "GET", url, nil, &streams)
+	if err != nil {
+		return nil, fmt.Errorf("couldn't get streams info: %w", err)
+	}
+	return streams, nil
+}

twitch/streams_test.go

@@ -0,0 +1,57 @@
+package twitch
+
+import (
+	"context"
+	"net/http"
+	"testing"
+	"time"
+
+	"github.com/google/go-cmp/cmp"
+	"golang.org/x/oauth2"
+)
+
+func TestUserStreams(t *testing.T) {
+	// Test that we successfully interpret the example response in the API doc.
+	t.Run("decode", func(t *testing.T) {
+		spy := apiresp(200, "streams.json")
+		cl := Client{
+			HTTP: &http.Client{
+				Transport: spy,
+			},
+			Token: &oauth2.Token{
+				AccessToken: "bocchi",
+			},
+		}
+		s := []Stream{
+			{UserID: "98765"},
+			{UserLogin: "sandysanderman"},
+		}
+		s, err := UserStreams(context.Background(), cl, s)
+		if err != nil {
+			t.Error(err)
+		}
+		if len(s) != 1 {
+			t.Fatalf("wrong number of results: want 1, got %d", len(s))
+		}
+		want := Stream{
+			ID:           "40952121085",
+			UserID:       "101051819",
+			UserLogin:    "afro",
+			UserName:     "Afro",
+			GameID:       "32982",
+			GameName:     "Grand Theft Auto V",
+			Type:         "live",
+			Title:        "Jacob: Digital Den Laptops & Routers | NoPixel | !MAINGEAR !FCF",
+			Tags:         []string{"English"},
+			ViewerCount:  1490,
+			StartedAt:    time.Date(2021, 3, 10, 3, 18, 11, 0, time.UTC),
+			Language:     "en",
+			ThumbnailURL: "https://static-cdn.jtvnw.net/previews-ttv/live_user_afro-{width}x{height}.jpg",
+			IsMature:     false,
+		}
+		got := s[0]
+		if diff := cmp.Diff(got, want); diff != "" {
+			t.Errorf("wrong result (+got/-want):\n%s", diff)
+		}
+	})
+}

twitch/testdata/streams.json

@@ -0,0 +1,24 @@
+{
+	"data": [
+		{
+			"id": "40952121085",
+			"user_id": "101051819",
+			"user_login": "afro",
+			"user_name": "Afro",
+			"game_id": "32982",
+			"game_name": "Grand Theft Auto V",
+			"type": "live",
+			"title": "Jacob: Digital Den Laptops & Routers | NoPixel | !MAINGEAR !FCF",
+			"tags": [
+				"English"
+			],
+			"viewer_count": 1490,
+			"started_at": "2021-03-10T03:18:11Z",
+			"language": "en",
+			"thumbnail_url": "https://static-cdn.jtvnw.net/previews-ttv/live_user_afro-{width}x{height}.jpg",
+			"tag_ids": [],
+			"is_mature": false
+		}
+	],
+	"pagination": {}
+}

twitch/twitch_test.go

@@ -2,10 +2,11 @@ package twitch
 
 import (
 	"context"
-	_ "embed"
+	"embed"
 	"errors"
 	"io"
 	"net/http"
+	"path"
 	"strings"
 	"testing"
 
@@ -27,6 +28,23 @@ func (r *reqspy) RoundTrip(req *http.Request) (*http.Response, error) {
 	return r.respond, nil
 }
 
+//go:embed testdata/*.json
+var jsonFiles embed.FS
+
+// apiresp creates a reqspy responding with the given testdata document.
+func apiresp(status int, file string) *reqspy {
+	f, err := jsonFiles.Open(path.Join("testdata/", file))
+	if err != nil {
+		panic(err)
+	}
+	return &reqspy{
+		respond: &http.Response{
+			StatusCode: status,
+			Body:       f,
+		},
+	}
+}
+
 func TestReqJSON(t *testing.T) {
 	t.Run("ok", func(t *testing.T) {
 		spy := &reqspy{