User collection API additions (#42)

User collection endpoint

README.md

@@ -6,7 +6,7 @@ go-discogs is a Go client library for the [Discogs API](https://www.discogs.com/
 
 The lib is under MIT but be sure you are familiar with [Discogs API Terms of Use](https://support.discogs.com/hc/en-us/articles/360009334593-API-Terms-of-Use).
 
-### Feauteres
+### Features
  * Database
     * [Releases](#releases)
     * Release Rating
@@ -17,6 +17,11 @@ The lib is under MIT but be sure you are familiar with [Discogs API Terms of Use
     * Label
     * All Label Releases
  * [Search](#search)
+ * [User Collection](#user-collection)
+    * Collection Folders
+    * Folder
+    * Collection Items by Folder
+    * Collection Items by Release
  
 Install
 --------
@@ -30,7 +35,7 @@ First of all import library and init client variable. According to discogs api d
 import "github.com/irlndts/go-discogs"
 ```
 
-Some requests require authentification (as any user). According to [Discogs](https://www.discogs.com/developers/#page:authentication,header:authentication-discogs-auth-flow), to send requests with Discogs Auth, you have two options: sending your credentials in the query string with key and secret parameters or a [token parameter](https://www.discogs.com/settings/developers).
+Some requests require authentication (as any user). According to [Discogs](https://www.discogs.com/developers/#page:authentication,header:authentication-discogs-auth-flow), to send requests with Discogs Auth, you have two options: sending your credentials in the query string with key and secret parameters or a [token parameter](https://www.discogs.com/settings/developers).
 
 ```go
 client, err := discogs.New(&discogs.Options{
@@ -88,3 +93,28 @@ Example
     fmt.Println(r.Title)
   }
 ```
+
+#### User Collection
+
+Query a users [collection](https://www.discogs.com/developers#page:user-collection).
+
+##### Collection Folders
+Example
+```go
+  collection, err := client.CollectionFolders("my_user")
+```
+##### Folder
+Example
+```go
+  folder, err := client.Folder("my_user", 0)
+```
+##### Collection Items by Folder
+Example
+```go
+  items, err := client.CollectionItemsByFolder("my_user", 0, &Pagination{Sort: "artist", SortOrder: "desc", PerPage: 2})
+```
+##### Collection Items by Release
+Example
+```go
+  items, err := client.CollectionItemsByRelease("my_user", 12934893)
+```

discogs.go

@@ -26,11 +26,13 @@ type Options struct {
 
 // Discogs is an interface for making Discogs API requests.
 type Discogs interface {
+	CollectionService
 	DatabaseService
 	SearchService
 }
 
 type discogs struct {
+	CollectionService
 	DatabaseService
 	SearchService
 }
@@ -62,6 +64,7 @@ func New(o *Options) (Discogs, error) {
 	}
 
 	return discogs{
+		newCollectionService(o.URL + "/users"),
 		newDatabaseService(o.URL, cur),
 		newSearchService(o.URL + "/database/search"),
 	}, nil

discogs_test.go

@@ -6,6 +6,7 @@ import (
 
 const (
 	testUserAgent = "UnitTestClient/0.0.2"
+	testUsername  = "test_user"
 	testToken     = ""
 )
 

errors.go

@@ -19,4 +19,7 @@ var (
 	ErrUnauthorized         = &Error{"authentication required"}
 	ErrCurrencyNotSupported = &Error{"currency does not supported"}
 	ErrUserAgentInvalid     = &Error{"invalid user-agent"}
+	ErrInvalidReleaseID     = &Error{"invalid release id"}
+	ErrInvalidSortKey       = &Error{"invalid sort key"}
+	ErrInvalidUsername      = &Error{"invalid username"}
 )

models.go

@@ -78,6 +78,7 @@ type Format struct {
 	Descriptions []string `json:"descriptions"`
 	Name         string   `json:"name"`
 	Qty          string   `json:"qty"`
+	Text         string   `json:"text,omitempty"`
 }
 
 // Company ...
@@ -130,8 +131,8 @@ type Page struct {
 
 // URLsList ...
 type URLsList struct {
-	Last string `json:"last"`
+	Last string `json:"last,omitempty"`
-	Next string `json:"next"`
+	Next string `json:"next,omitempty"`
 }
 
 // Version ...
@@ -188,7 +189,9 @@ type ReleaseSource struct {
 
 // Pagination ...
 type Pagination struct {
-	Sort      string // year, title, format
+	// TODO(irlndts): validate requested Sort
+	Sort string // year, title, format etc
+	// TODO(irlndts): validate requested SortOrder
 	SortOrder string // asc, desc
 	Page      int
 	PerPage   int

user_collection.go

@@ -0,0 +1,135 @@
+package discogs
+
+import (
+	"strconv"
+)
+
+// CollectionService is an interface to work with collection.
+type CollectionService interface {
+	// Retrieve a list of folders in a user’s collection.
+	// If folder_id is not 0, authentication as the collection owner is required.
+	CollectionFolders(username string) (*CollectionFolders, error)
+	// Retrieve a list of items in a folder in a user’s collection.
+	// If folderID is not 0, authentication with token is required.
+	CollectionItemsByFolder(username string, folderID int, pagination *Pagination) (*CollectionItems, error)
+	// Retrieve the user’s collection folders which contain a specified release.
+	// The releaseID must be non-zero.
+	CollectionItemsByRelease(username string, releaseID int) (*CollectionItems, error)
+	// Retrieve metadata about a folder in a user’s collection.
+	Folder(username string, folderID int) (*Folder, error)
+}
+
+type collectionService struct {
+	url string
+}
+
+func newCollectionService(url string) CollectionService {
+	return &collectionService{
+		url: url,
+	}
+}
+
+// Folder serves folder response from discogs.
+type Folder struct {
+	ID          int    `json:"id"`
+	Count       int    `json:"count"`
+	Name        string `json:"name"`
+	ResourceURL string `json:"resource_url"`
+}
+
+func (s *collectionService) Folder(username string, folderID int) (*Folder, error) {
+	if username == "" {
+		return nil, ErrInvalidUsername
+	}
+	var folder *Folder
+	err := request(s.url+"/"+username+"/collection/folders/"+strconv.Itoa(folderID), nil, &folder)
+	return folder, err
+}
+
+// CollectionFolders serves collection response from discogs.
+type CollectionFolders struct {
+	Folders []Folder `json:"folders"`
+}
+
+func (s *collectionService) CollectionFolders(username string) (*CollectionFolders, error) {
+	if username == "" {
+		return nil, ErrInvalidUsername
+	}
+	var collection *CollectionFolders
+	err := request(s.url+"/"+username+"/collection/folders", nil, &collection)
+	return collection, err
+}
+
+// CollectionItemSource ...
+type CollectionItemSource struct {
+	ID               int              `json:"id"`
+	BasicInformation BasicInformation `json:"basic_information"`
+	DateAdded        string           `json:"date_added"`
+	FolderID         int              `json:"folder_id,omitempty"`
+	InstanceID       int              `json:"instance_id"`
+	Notes            string           `json:"notes,omitempty"`
+	Rating           int              `json:"rating"`
+}
+
+// BasicInformation ...
+type BasicInformation struct {
+	ID          int            `json:"id"`
+	Artists     []ArtistSource `json:"artists"`
+	CoverImage  string         `json:"cover_image"`
+	Formats     []Format       `json:"formats"`
+	Labels      []LabelSource  `json:"labels"`
+	Genres      []string       `json:"genres"`
+	MasterID    int            `json:"master_id"`
+	MasterURL   *string        `json:"master_url"`
+	ResourceURL string         `json:"resource_url"`
+	Styles      []string       `json:"styles"`
+	Thumb       string         `json:"thumb"`
+	Title       string         `json:"title"`
+	Year        int            `json:"year"`
+}
+
+// CollectionItems list of items in a user’s collection
+type CollectionItems struct {
+	Pagination Page                   `json:"pagination"`
+	Items      []CollectionItemSource `json:"releases"`
+}
+
+// valid sort keys
+// https://www.discogs.com/developers#page:user-collection,header:user-collection-collection-items-by-folder
+var validItemsByFolderSort = map[string]struct{}{
+	"":       struct{}{},
+	"label":  struct{}{},
+	"artist": struct{}{},
+	"title":  struct{}{},
+	"catno":  struct{}{},
+	"format": struct{}{},
+	"rating": struct{}{},
+	"added":  struct{}{},
+	"year":   struct{}{},
+}
+
+func (s *collectionService) CollectionItemsByFolder(username string, folderID int, pagination *Pagination) (*CollectionItems, error) {
+	if username == "" {
+		return nil, ErrInvalidUsername
+	}
+	if pagination != nil {
+		if _, ok := validItemsByFolderSort[pagination.Sort]; !ok {
+			return nil, ErrInvalidSortKey
+		}
+	}
+	var items *CollectionItems
+	err := request(s.url+"/"+username+"/collection/folders/"+strconv.Itoa(folderID)+"/releases", pagination.params(), &items)
+	return items, err
+}
+
+func (s *collectionService) CollectionItemsByRelease(username string, releaseID int) (*CollectionItems, error) {
+	if username == "" {
+		return nil, ErrInvalidUsername
+	}
+	if releaseID == 0 {
+		return nil, ErrInvalidReleaseID
+	}
+	var items *CollectionItems
+	err := request(s.url+"/"+username+"/collection/releases/"+strconv.Itoa(releaseID), nil, &items)
+	return items, err
+}

user_collection_test.go

@@ -0,0 +1,174 @@
+package discogs
+
+import (
+	"encoding/json"
+	"io"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+)
+
+func CollectionServer(w http.ResponseWriter, r *http.Request) {
+	if r.Method != "GET" {
+		w.WriteHeader(http.StatusMethodNotAllowed)
+		return
+	}
+
+	switch r.URL.Path {
+	case "/users/" + testUsername + "/collection/folders":
+		w.WriteHeader(http.StatusOK)
+		if _, err := io.WriteString(w, collectionJson); err != nil {
+			w.WriteHeader(http.StatusInternalServerError)
+			return
+		}
+
+	case "/users/" + testUsername + "/collection/folders/0":
+		w.WriteHeader(http.StatusOK)
+		if _, err := io.WriteString(w, folderJson); err != nil {
+			w.WriteHeader(http.StatusInternalServerError)
+			return
+		}
+
+	case "/users/" + testUsername + "/collection/folders/0/releases":
+		w.WriteHeader(http.StatusOK)
+		if _, err := io.WriteString(w, collectionItemsByFolderJson); err != nil {
+			w.WriteHeader(http.StatusInternalServerError)
+			return
+		}
+
+	case "/users/" + testUsername + "/collection/releases/12934893":
+		w.WriteHeader(http.StatusOK)
+		if _, err := io.WriteString(w, collectionItemsByRelease); err != nil {
+			w.WriteHeader(http.StatusInternalServerError)
+			return
+		}
+
+	default:
+		w.WriteHeader(http.StatusMethodNotAllowed)
+	}
+}
+
+func TestCollectionServiceFolder(t *testing.T) {
+	ts := httptest.NewServer(http.HandlerFunc(CollectionServer))
+	defer ts.Close()
+
+	d := initDiscogsClient(t, &Options{URL: ts.URL})
+
+	folder, err := d.Folder(testUsername, 0)
+	if err != nil {
+		t.Fatalf("failed to get folder: %s", err)
+	}
+
+	json, err := json.Marshal(folder)
+	if err != nil {
+		t.Fatalf("failed to marshal folder: %s", err)
+	}
+
+	compareJson(t, string(json), folderJson)
+}
+
+func TestCollectionServiceCollectionFolders(t *testing.T) {
+	ts := httptest.NewServer(http.HandlerFunc(CollectionServer))
+	defer ts.Close()
+
+	d := initDiscogsClient(t, &Options{URL: ts.URL})
+
+	collection, err := d.CollectionFolders(testUsername)
+	if err != nil {
+		t.Fatalf("failed to get collection: %s", err)
+	}
+
+	json, err := json.Marshal(collection)
+	if err != nil {
+		t.Fatalf("failed to marshal collection: %s", err)
+	}
+
+	compareJson(t, string(json), collectionJson)
+}
+
+func TestCollectionServiceCollectionItemsByFolder(t *testing.T) {
+	ts := httptest.NewServer(http.HandlerFunc(CollectionServer))
+	defer ts.Close()
+
+	d := initDiscogsClient(t, &Options{URL: ts.URL})
+
+	items, err := d.CollectionItemsByFolder(testUsername, 0, &Pagination{Sort: "artist", SortOrder: "desc", PerPage: 2})
+
+	if err != nil {
+		t.Fatalf("failed to get collection items: %s", err)
+	}
+
+	json, err := json.Marshal(items)
+	if err != nil {
+		t.Fatalf("failed to marshal collection items: %s", err)
+	}
+
+	compareJson(t, string(json), collectionItemsByFolderJson)
+}
+
+func TestCollectionServiceCollectionItemsByFolderError(t *testing.T) {
+	ts := httptest.NewServer(http.HandlerFunc(CollectionServer))
+	defer ts.Close()
+
+	d := initDiscogsClient(t, &Options{URL: ts.URL})
+
+	_, err := d.CollectionItemsByFolder(testUsername, 0, &Pagination{Sort: "invalid"})
+	if err != ErrInvalidSortKey {
+		t.Fatalf("err got=%s; want=%s", err, ErrInvalidSortKey)
+	}
+}
+
+func TestCollectionServiceCollectionItemsByRelease(t *testing.T) {
+	ts := httptest.NewServer(http.HandlerFunc(CollectionServer))
+	defer ts.Close()
+
+	d := initDiscogsClient(t, &Options{URL: ts.URL})
+
+	items, err := d.CollectionItemsByRelease(testUsername, 12934893)
+
+	if err != nil {
+		t.Fatalf("failed to get collection items: %s", err)
+	}
+
+	json, err := json.Marshal(items)
+	if err != nil {
+		t.Fatalf("failed to marshal collection items: %s", err)
+	}
+
+	compareJson(t, string(json), collectionItemsByRelease)
+}
+
+func TestCollectionServiceCollectionItemsByReleaseErrors(t *testing.T) {
+	ts := httptest.NewServer(http.HandlerFunc(CollectionServer))
+	defer ts.Close()
+	d := initDiscogsClient(t, &Options{URL: ts.URL})
+
+	type testCase struct {
+		username  string
+		releaseID int
+		err       error
+	}
+
+	testCases := map[string]testCase{
+		"invalid username": testCase{
+			username:  "",
+			releaseID: 1,
+			err:       ErrInvalidUsername,
+		},
+		"invalid release id": testCase{
+			username:  "test-username",
+			releaseID: 0,
+			err:       ErrInvalidReleaseID,
+		},
+	}
+
+	for name, tc := range testCases {
+		tc := tc
+		t.Run(name, func(t *testing.T) {
+			_, err := d.CollectionItemsByRelease(tc.username, tc.releaseID)
+			if err != tc.err {
+				t.Fatalf("err got=%s; want=%s", err, tc.err)
+			}
+		})
+	}
+}