Add GetAccountsBalance()

README.md

@@ -97,6 +97,7 @@ If you want to execute the Private API, you need to create a client with the API
 | API | Method Name |Description |
 | :--- | :--- | :--- |
 | GET /api/bank_accounts | [GetBankAccounts()](https://pkg.go.dev/github.com/nao1215/coincheck#Client.GetBankAccounts) | Display list of bank account you registered (withdrawal).|
+| GET /api/accounts/balance | [GetAccountsBalance()](https://pkg.go.dev/github.com/nao1215/coincheck#Client.GetAccountsBalance) | Get the balance of your account. |
 
 ## License
 

balance.go

@@ -0,0 +1,57 @@
+package coincheck
+
+import (
+	"context"
+	"net/http"
+)
+
+// GetAccountsBalanceResponse represents the response from the GetAccountsBalance method.
+type GetAccountsBalanceResponse struct {
+	// Success is true if the request was successful.
+	Success bool `json:"success"`
+	// JPY is the balance of JPY.
+	JPY string `json:"jpy"`
+	// BTC is the balance of BTC.
+	BTC string `json:"btc"`
+	// JPYReserved is amount of JPY for unsettled buying order
+	JPYReserved string `json:"jpy_reserved"`
+	// BTCReserved is amount of BTC for unsettled selling order
+	BTCReserved string `json:"btc_reserved"`
+	// JPYLendInUse is JPY amount you are applying for lending (We don't allow you to loan JPY.)
+	JPYLendInUse string `json:"jpy_lend_in_use"`
+	// BTCLendInUse is BTC Amount you are applying for lending (We don't allow you to loan BTC.)
+	BTCLendInUse string `json:"btc_lend_in_use"`
+	// JPYLent is JPY lending amount (Currently, we don't allow you to loan JPY.)
+	JPYLent string `json:"jpy_lent"`
+	// BTCLent is BTC lending amount (Currently, we don't allow you to loan BTC.)
+	BTCLent string `json:"btc_lent"`
+	// JPYDebt is JPY borrowing amount
+	JPYDebt string `json:"jpy_debt"`
+	// BTCDebt is BTC borrowing amount
+	BTCDebt string `json:"btc_debt"`
+	// JPYTsumitate is JPY reserving amount
+	JPYTsumitate string `json:"jpy_tsumitate"`
+	// BTCTsumitate is BTC reserving amount
+	BTCTsumitate string `json:"btc_tsumitate"`
+}
+
+// GetAccountsBalance returns the balance of the account.
+// API: GET /api/accounts/balance
+// Visibility: Private
+// It doesn't include jpy_reserved use unsettled orders (it's GET /api/exchange/orders/opens) in jpy btc.
+func (c *Client) GetAccountsBalance(ctx context.Context) (*GetAccountsBalanceResponse, error) {
+	req, err := c.createRequest(ctx, createRequestInput{
+		method:  http.MethodGet,
+		path:    "/api/accounts/balance",
+		private: true,
+	})
+	if err != nil {
+		return nil, err
+	}
+
+	var output GetAccountsBalanceResponse
+	if err := c.do(req, &output); err != nil {
+		return nil, err
+	}
+	return &output, nil
+}

balance_test.go

@@ -0,0 +1,111 @@
+package coincheck
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/google/go-cmp/cmp"
+)
+
+func TestClient_GetBalance(t *testing.T) {
+	t.Run("GetBalance returns the balance", func(t *testing.T) {
+		testServer := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			wantMethod := http.MethodGet
+			if diff := cmp.Diff(wantMethod, r.Method); diff != "" {
+				printDiff(t, diff)
+			}
+
+			wantEndpoint := "/api/accounts/balance"
+			if diff := cmp.Diff(wantEndpoint, r.URL.Path); diff != "" {
+				printDiff(t, diff)
+			}
+
+			result := GetAccountsBalanceResponse{
+				Success:      true,
+				JPY:          "0.8401",
+				BTC:          "7.75052654",
+				JPYReserved:  "3000.0",
+				BTCReserved:  "3.5002",
+				JPYLendInUse: "1.1",
+				BTCLendInUse: "0.3",
+				JPYLent:      "0",
+				BTCLent:      "1.2",
+				JPYDebt:      "0",
+				BTCDebt:      "0",
+				JPYTsumitate: "10000.0",
+				BTCTsumitate: "0.43034",
+			}
+			if err := json.NewEncoder(w).Encode(result); err != nil {
+				t.Fatal(err)
+			}
+		}))
+
+		client, err := NewClient(
+			WithBaseURL(testServer.URL),
+			WithCredentials("api_key", "api_secret"),
+		)
+		if err != nil {
+			t.Fatal(err)
+		}
+
+		got, err := client.GetAccountsBalance(context.Background())
+		if err != nil {
+			t.Fatal(err)
+		}
+
+		want := &GetAccountsBalanceResponse{
+			Success:      true,
+			JPY:          "0.8401",
+			BTC:          "7.75052654",
+			JPYReserved:  "3000.0",
+			BTCReserved:  "3.5002",
+			JPYLendInUse: "1.1",
+			BTCLendInUse: "0.3",
+			JPYLent:      "0",
+			BTCLent:      "1.2",
+			JPYDebt:      "0",
+			BTCDebt:      "0",
+			JPYTsumitate: "10000.0",
+			BTCTsumitate: "0.43034",
+		}
+		if diff := cmp.Diff(want, got); diff != "" {
+			printDiff(t, diff)
+		}
+	})
+
+	t.Run("GetBalance returns an error if the server returns an error", func(t *testing.T) {
+		testServer := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, _ *http.Request) {
+			w.WriteHeader(http.StatusInternalServerError)
+		}))
+
+		client, err := NewClient(
+			WithBaseURL(testServer.URL),
+			WithCredentials("api_key", "api_secret"),
+		)
+		if err != nil {
+			t.Fatal(err)
+		}
+
+		_, err = client.GetAccountsBalance(context.Background())
+		if err == nil {
+			t.Fatal("GetBalance did not return an error")
+		}
+	})
+	t.Run("GetBankAccounts returns an error if client does not set credentials", func(t *testing.T) {
+		// Create a new client
+		client, err := NewClient(WithBaseURL("https://example.com"))
+		if err != nil {
+			t.Fatal(err)
+		}
+
+		// Start testing
+		_, err = client.GetAccountsBalance(context.Background())
+		if !errors.Is(err, ErrNoCredentials) {
+			t.Errorf("error is not ErrNoCredentials: %v", err)
+		}
+	})
+}

coincheck.go

@@ -79,6 +79,7 @@ type createRequestInput struct {
 	path       string            // API path (e.g. /api/orders)
 	body       io.Reader         // Request body. If you don't need it, set nil.
 	queryParam map[string]string // Query parameters (e.g. {"pair": "btc_jpy"}) If you don't need it, set nil.
+	private    bool              // If true, it's a private API.
 }
 
 // createRequest creates a new HTTP request.
@@ -108,6 +109,12 @@ func (c *Client) createRequest(ctx context.Context, input createRequestInput) (*
 
 	req.Header.Add("content-type", "application/json")
 	req.Header.Add("cache-control", "no-cache")
+	if input.private {
+		if err := c.setAuthHeaders(req, ""); err != nil {
+			return nil, err
+		}
+	}
+
 	return req, nil
 }
 

withdraw.go

@@ -34,15 +34,13 @@ type BankAccount struct {
 // Visibility: Private
 func (c *Client) GetBankAccounts(ctx context.Context) (*GetBankAccountsResponse, error) {
 	req, err := c.createRequest(ctx, createRequestInput{
-		method: http.MethodGet,
-		path:   "/api/bank_accounts",
+		method:  http.MethodGet,
+		path:    "/api/bank_accounts",
+		private: true,
 	})
 	if err != nil {
 		return nil, err
 	}
-	if err := c.setAuthHeaders(req, ""); err != nil {
-		return nil, err
-	}
 
 	var output GetBankAccountsResponse
 	if err := c.do(req, &output); err != nil {