Set up default currency accounts automatically (#72)

2026-10-23 12:43:55 +02:00
1 parent 62df9eac5f
commit 5c255296d3
@@ -0,0 +1,87 @@
+package sendico
+
+import (
+	"context"
+	"net/http"
+
+	"git.sendico.io/tech/sxchnge/product/payments"
+	merrors "git.sendico.io/tech/sxchnge/shared/errors"
+)
+
+func (c *Client) validCustomerAccount(a accountDTO, subject string) bool {
+	return validRef(a.ID) && a.ScopeRef == c.config.OrganizationID && a.Owner == "" &&
+		a.Type == "ACCOUNT_TYPE_ASSET" && a.LedgerRole == "ACCOUNT_ROLE_OPERATING" &&
+		a.Status == "ACCOUNT_STATUS_ACTIVE" && !a.AllowNegative && a.Metadata["sxchnge_subject_ref"] == subject &&
+		(a.Metadata["external_subject_ref"] == "" || a.Metadata["external_subject_ref"] == subject)
+}
+
+// EnsureAccounts also repairs older customers, using provider-enforced
+// organization/subject/currency uniqueness for safe retries after lost responses.
+func (c *Client) EnsureAccounts(ctx context.Context, subject string) error {
+	if !validRef(subject) {
+		return payments.Unavailable
+	}
+	root := "/ledger_accounts/" + c.config.OrganizationID
+	var data accountListDTO
+	if err := c.paymentRequest(ctx, http.MethodGet, root, nil, &data); err != nil {
+		return err
+	}
+	existing := map[string]bool{}
+	reconcile := map[string]bool{}
+	for _, a := range data.Accounts {
+		if a.Metadata["sxchnge_subject_ref"] != subject && a.Metadata["external_subject_ref"] != subject {
+			continue
+		}
+		if !c.validCustomerAccount(a, subject) || existing[a.Currency] {
+			return payments.Unavailable
+		}
+		existing[a.Currency] = true
+		reconcile[a.Currency] = a.Metadata["external_subject_ref"] == subject
+	}
+	missing := []string{}
+	for _, code := range []string{"RUB", "USDT", "USDC"} {
+		if !existing[code] || reconcile[code] {
+			missing = append(missing, code)
+		}
+	}
+	if len(missing) == 0 {
+		return nil
+	}
+	// Older providers can accept the metadata but cannot prevent duplicates.
+	// Require the explicit capability before issuing the first create.
+	if !data.ExternalSubjectAccounts {
+		return payments.Unavailable
+	}
+	var catalog struct {
+		Rows []currencyDTO `json:"currencies"`
+	}
+	if err := c.paymentRequest(ctx, http.MethodGet, "/payments/fx/currencies/"+c.config.OrganizationID, nil, &catalog); err != nil {
+		return err
+	}
+	for _, code := range missing {
+		found := false
+		for _, currency := range catalog.Rows {
+			if currency.Code == code && currency.Scale != nil && *currency.Scale >= 0 && *currency.Scale <= 8 {
+				found = true
+			}
+		}
+		if !found {
+			return merrors.OpaqueWrap(payments.Unavailable, payments.Unsupported, "default currency missing from provider catalog")
+		}
+	}
+	// Replaying a bound create also resumes Sendico's durable wallet/route setup
+	// if a previous response failed after the ledger itself had been committed.
+	for _, code := range missing {
+		var response struct {
+			Account accountDTO `json:"account"`
+		}
+		request := createAccountDTO{Currency: code, Type: "asset", LedgerRole: "operating", Metadata: map[string]string{"external_subject_ref": subject, "sxchnge_subject_ref": subject}}
+		if err := c.paymentRequest(ctx, http.MethodPost, root, request, &response, http.StatusCreated); err != nil {
+			return err
+		}
+		if !c.validCustomerAccount(response.Account, subject) || response.Account.Currency != code || response.Account.Metadata["external_subject_ref"] != subject {
+			return payments.Unavailable
+		}
+	}
+	return nil
+}
@@ -0,0 +1,200 @@
+package sendico
+
+import (
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"sync"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+	"go.mongodb.org/mongo-driver/v2/bson"
+)
+
+type accountServer struct {
+	mu              sync.Mutex
+	rows            []accountDTO
+	posts           []string
+	capable         bool
+	missingCurrency bool
+	failCurrency    string
+	loseResponse    bool
+	wrongResponse   bool
+}
+
+func customerLedger(code string) accountDTO {
+	return accountDTO{ID: bson.NewObjectID().Hex(), ScopeRef: org, Currency: code, Type: "ACCOUNT_TYPE_ASSET", LedgerRole: "ACCOUNT_ROLE_OPERATING", Status: "ACCOUNT_STATUS_ACTIVE", Metadata: map[string]string{"sxchnge_subject_ref": subject, "external_subject_ref": subject}}
+}
+
+func (s *accountServer) serve(t *testing.T) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		s.mu.Lock()
+		defer s.mu.Unlock()
+		require.NotEmpty(t, r.Header.Get("Authorization"))
+		var data any
+		switch {
+		case strings.Contains(r.URL.Path, "/currencies/"):
+			rows := []map[string]any{{"code": "RUB", "accountingScale": 2}, {"code": "USDT", "accountingScale": 6}, {"code": "USDC", "accountingScale": 6}}
+			if s.missingCurrency {
+				rows = rows[:2]
+			}
+			data = map[string]any{"currencies": rows}
+		case r.Method == http.MethodPost:
+			var request createAccountDTO
+			require.NoError(t, json.NewDecoder(r.Body).Decode(&request))
+			require.Equal(t, "asset", request.Type)
+			require.Equal(t, "operating", request.LedgerRole)
+			require.False(t, request.AllowNegative)
+			require.Equal(t, subject, request.Metadata["external_subject_ref"])
+			require.Equal(t, subject, request.Metadata["sxchnge_subject_ref"])
+			s.posts = append(s.posts, request.Currency)
+			if s.failCurrency == request.Currency {
+				s.failCurrency = ""
+				w.WriteHeader(503)
+				return
+			}
+			var row accountDTO
+			for _, a := range s.rows {
+				if a.Currency == request.Currency && a.Metadata["external_subject_ref"] == subject {
+					row = a
+				}
+			}
+			if row.ID == "" {
+				row = customerLedger(request.Currency)
+				s.rows = append(s.rows, row)
+			}
+			if s.loseResponse {
+				s.loseResponse = false
+				w.WriteHeader(503)
+				return
+			}
+			if s.wrongResponse {
+				row.Currency = "EUR"
+			}
+			w.WriteHeader(http.StatusCreated)
+			data = map[string]any{"account": row}
+		case strings.HasSuffix(r.URL.Path, "/balance"):
+			parts := strings.Split(r.URL.Path, "/")
+			data = map[string]any{"balance": balanceDTO{ID: parts[len(parts)-2], Money: moneyDTO{Amount: "45.00", Currency: "RUB"}}}
+		default:
+			data = map[string]any{"accounts": s.rows, "externalSubjectAccounts": s.capable}
+		}
+		require.NoError(t, json.NewEncoder(w).Encode(map[string]any{"status": "success", "data": data}))
+	}
+}
+
+func TestEnsureCurrencyAccountsPreservesExistingAndRecoversPartialFailure(t *testing.T) {
+	for _, lost := range []bool{false, true} {
+		t.Run(map[bool]string{false: "partial failure", true: "lost response"}[lost], func(t *testing.T) {
+			s := &accountServer{capable: true, failCurrency: "USDT", loseResponse: lost}
+			if lost {
+				s.failCurrency = ""
+			}
+			server := httptest.NewServer(s.serve(t))
+			defer server.Close()
+			c, err := Open(config(t, server.URL))
+			require.NoError(t, err)
+			require.Error(t, c.EnsureAccounts(t.Context(), subject))
+			require.Len(t, s.rows, 1)
+			firstID := s.rows[0].ID
+			require.NoError(t, c.EnsureAccounts(t.Context(), subject))
+			require.NoError(t, c.EnsureAccounts(t.Context(), subject))
+			require.Len(t, s.rows, 3)
+			require.Equal(t, firstID, s.rows[0].ID)
+			// Bound creates are replayed to finish interrupted wallet/route setup;
+			// the provider must return the original ledger each time.
+			require.Equal(t, 3, countCurrency(s.posts, "RUB"))
+		})
+	}
+}
+
+func countCurrency(rows []string, code string) int {
+	n := 0
+	for _, r := range rows {
+		if r == code {
+			n++
+		}
+	}
+	return n
+}
+
+func TestEnsureAccountsConcurrentRequestsUseStableSubjectBinding(t *testing.T) {
+	s := &accountServer{capable: true}
+	server := httptest.NewServer(s.serve(t))
+	defer server.Close()
+	c, err := Open(config(t, server.URL))
+	require.NoError(t, err)
+	errors := make(chan error, 12)
+	for range 12 {
+		go func() { errors <- c.EnsureAccounts(t.Context(), subject) }()
+	}
+	for range 12 {
+		require.NoError(t, <-errors)
+	}
+	require.Len(t, s.rows, 3)
+}
+
+func TestEnsureAccountsRejectsUnsafeProviderStateBeforeCreating(t *testing.T) {
+	for _, kind := range []string{"old provider", "missing currency", "frozen", "owned", "negative", "duplicate", "wrong subject"} {
+		t.Run(kind, func(t *testing.T) {
+			s := &accountServer{capable: true}
+			a := customerLedger("RUB")
+			switch kind {
+			case "old provider":
+				s.capable = false
+			case "missing currency":
+				s.missingCurrency = true
+			case "frozen":
+				a.Status = "ACCOUNT_STATUS_FROZEN"
+				s.rows = []accountDTO{a}
+			case "owned":
+				a.Owner = source
+				s.rows = []accountDTO{a}
+			case "negative":
+				a.AllowNegative = true
+				s.rows = []accountDTO{a}
+			case "duplicate":
+				s.rows = []accountDTO{a, customerLedger("RUB")}
+			case "wrong subject":
+				a.Metadata["sxchnge_subject_ref"] = source
+				s.rows = []accountDTO{a}
+			}
+			server := httptest.NewServer(s.serve(t))
+			defer server.Close()
+			c, err := Open(config(t, server.URL))
+			require.NoError(t, err)
+			require.Error(t, c.EnsureAccounts(t.Context(), subject))
+			require.Empty(t, s.posts)
+		})
+	}
+}
+
+func TestEnsureAccountsValidatesCreateReceipt(t *testing.T) {
+	s := &accountServer{capable: true, wrongResponse: true}
+	server := httptest.NewServer(s.serve(t))
+	defer server.Close()
+	c, err := Open(config(t, server.URL))
+	require.NoError(t, err)
+	require.Error(t, c.EnsureAccounts(t.Context(), subject))
+	require.Len(t, s.posts, 1)
+}
+
+func TestEnsureAccountsKeepsExistingBindingsAndBalances(t *testing.T) {
+	a := customerLedger("RUB")
+	delete(a.Metadata, "external_subject_ref")
+	s := &accountServer{capable: true, rows: []accountDTO{a}}
+	server := httptest.NewServer(s.serve(t))
+	defer server.Close()
+	c, err := Open(config(t, server.URL))
+	require.NoError(t, err)
+	require.NoError(t, c.EnsureAccounts(t.Context(), subject))
+	require.Equal(t, []string{"USDT", "USDC"}, s.posts)
+	// A subsequent read uses the original RUB ledger and its authoritative funds.
+	s.rows = s.rows[:1]
+	accounts, err := c.Accounts(t.Context(), subject)
+	require.NoError(t, err)
+	require.Len(t, accounts, 1)
+	require.Equal(t, a.ID, accounts[0].ID)
+	require.EqualValues(t, 4500, accounts[0].Available)
+}
@@ -0,0 +1,14 @@
+package sendico
+
+type accountListDTO struct {
+	Accounts                []accountDTO `json:"accounts"`
+	ExternalSubjectAccounts bool         `json:"externalSubjectAccounts"`
+}
+
+type createAccountDTO struct {
+	Currency      string            `json:"currency"`
+	Type          string            `json:"accountType"`
+	LedgerRole    string            `json:"role"`
+	AllowNegative bool              `json:"allowNegative"`
+	Metadata      map[string]string `json:"metadata"`
+}
@@ -27,9 +27,7 @@ func (c *Client) Accounts(ctx context.Context, subject string) ([]payments.Accou
 			scales[row.Code] = *row.Scale
 		}
 	}
-	var data struct {
-		Accounts []accountDTO `json:"accounts"`
-	}
+	var data accountListDTO
 	root := "/ledger_accounts/" + c.config.OrganizationID
 	if err := c.paymentRequest(ctx, http.MethodGet, root, nil, &data); err != nil {
 		return nil, err
@@ -39,7 +37,7 @@ func (c *Client) Accounts(ctx context.Context, subject string) ([]payments.Accou
 		if row.Metadata["sxchnge_subject_ref"] != subject {
 			continue
 		}
-		if !validRef(row.ID) || row.ScopeRef != c.config.OrganizationID || row.Owner != "" || row.Status != "ACCOUNT_STATUS_ACTIVE" || row.Type != "ACCOUNT_TYPE_ASSET" || row.LedgerRole != "ACCOUNT_ROLE_OPERATING" {
+		if !c.validCustomerAccount(row, subject) {
 			return nil, payments.Unavailable
 		}
 		scale, ok := scales[row.Currency]
@@ -54,14 +54,15 @@ type paymentDTO struct {
 	Created time.Time       `json:"createdAt"`
 }
 type accountDTO struct {
-	ID         string            `json:"ledgerAccountRef"`
-	ScopeRef   string            `json:"organizationRef"`
-	Owner      string            `json:"ownerRef"`
-	Currency   string            `json:"currency"`
-	Type       string            `json:"accountType"`
-	LedgerRole string            `json:"role"`
-	Status     string            `json:"status"`
-	Metadata   map[string]string `json:"metadata"`
+	ID            string            `json:"ledgerAccountRef"`
+	ScopeRef      string            `json:"organizationRef"`
+	Owner         string            `json:"ownerRef"`
+	Currency      string            `json:"currency"`
+	Type          string            `json:"accountType"`
+	LedgerRole    string            `json:"role"`
+	Status        string            `json:"status"`
+	AllowNegative bool              `json:"allowNegative"`
+	Metadata      map[string]string `json:"metadata"`
 }
 type currencyDTO struct {
 	Code  string `json:"code"`
@@ -72,7 +73,7 @@ type balanceDTO struct {
 	Money moneyDTO `json:"balance"`
 }

-func (c *Client) paymentRequest(ctx context.Context, method, path string, payload, dst any) error {
+func (c *Client) paymentRequest(ctx context.Context, method, path string, payload, dst any, accepted ...int) error {
 	token, err := c.token()
 	if err != nil {
 		return err
@@ -98,7 +99,11 @@ func (c *Client) paymentRequest(ctx context.Context, method, path string, payloa
 	}
 	defer func() { _ = res.Body.Close() }()
 	// Never forward upstream errors, credentials, or arbitrary error bodies.
-	if res.StatusCode != http.StatusOK {
+	expected := http.StatusOK
+	if len(accepted) != 0 {
+		expected = accepted[0]
+	}
+	if res.StatusCode != expected {
 		return payments.Unavailable
 	}
 	var envelope struct {