Lars Nolden
a8722d58c3
Manual history imports failed opaquely once a bank capped lookback on an established consent (N26 rejects date_from beyond ~90 days with WRONG_TRANSACTIONS_PERIOD). Backfill now requests the documented longest fetching strategy, reports the coverage the bank actually provided, and non-2xx responses surface allowlisted documented error codes instead of a generic fallback. Dead-session codes map to reconnection. Failed syncs retry hourly so a stale sync banner no longer persists for a day.
749 lines
31 KiB
Go
749 lines
31 KiB
Go
package banking
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import (
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"bytes"
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"context"
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"crypto"
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"crypto/rand"
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"crypto/rsa"
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"crypto/sha256"
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"crypto/x509"
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"encoding/base64"
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"encoding/json"
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"encoding/pem"
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"errors"
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"fmt"
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"io"
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"net/http"
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"net/http/httptest"
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"reflect"
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"strings"
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"sync/atomic"
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"testing"
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"time"
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"finance-duck/internal/ratelimit"
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)
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func testProvider(t *testing.T, handler http.HandlerFunc) (*EnableBanking, *rsa.PrivateKey) {
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t.Helper()
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key, err := rsa.GenerateKey(rand.Reader, 2048)
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if err != nil {
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t.Fatal(err)
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}
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keyPEM := pem.EncodeToMemory(&pem.Block{Type: "RSA PRIVATE KEY", Bytes: x509.MarshalPKCS1PrivateKey(key)})
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p, err := NewEnableBanking("test-app", keyPEM, "http://localhost:8080/api/banking/callback")
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if err != nil {
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t.Fatal(err)
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}
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server := httptest.NewServer(handler)
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t.Cleanup(server.Close)
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p.BaseURL = server.URL
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p.HTTPClient = server.Client()
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p.requests = ratelimit.Controller{}
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return p, key
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}
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func assertJWT(t *testing.T, r *http.Request, key *rsa.PrivateKey) {
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t.Helper()
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if !strings.HasPrefix(r.Header.Get("Authorization"), "Bearer ") {
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t.Error("missing Bearer authentication")
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return
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}
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parts := strings.Split(strings.TrimPrefix(r.Header.Get("Authorization"), "Bearer "), ".")
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if len(parts) != 3 {
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t.Error("invalid JWT structure")
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return
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}
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signature, err := base64.RawURLEncoding.DecodeString(parts[2])
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if err != nil {
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t.Error(err)
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return
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}
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hash := sha256.Sum256([]byte(parts[0] + "." + parts[1]))
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if err := rsa.VerifyPKCS1v15(&key.PublicKey, crypto.SHA256, hash[:], signature); err != nil {
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t.Errorf("invalid JWT signature: %v", err)
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}
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var header map[string]string
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b, err := base64.RawURLEncoding.DecodeString(parts[0])
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if err != nil {
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t.Error(err)
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return
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}
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if err := json.Unmarshal(b, &header); err != nil {
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t.Error(err)
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return
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}
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if header["alg"] != "RS256" || header["kid"] != "test-app" || header["typ"] != "JWT" {
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t.Errorf("wrong JWT header: %v", header)
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}
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var claims struct {
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Issuer string `json:"iss"`
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Audience string `json:"aud"`
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Issued int64 `json:"iat"`
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Expires int64 `json:"exp"`
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}
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b, err = base64.RawURLEncoding.DecodeString(parts[1])
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if err != nil {
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t.Error(err)
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return
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}
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if err := json.Unmarshal(b, &claims); err != nil {
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t.Error(err)
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return
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}
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now := time.Now().Unix()
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if claims.Issuer != "enablebanking.com" || claims.Audience != "api.enablebanking.com" || claims.Issued > now+1 || claims.Expires <= now || claims.Expires-claims.Issued > 86400 {
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t.Errorf("invalid JWT claims: %+v", claims)
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}
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}
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func TestEnableBankingDocumentedFlowAndPagination(t *testing.T) {
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var key *rsa.PrivateKey
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expiry := time.Now().Add(24 * time.Hour).UTC().Format(time.RFC3339)
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pages := 0
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handler := func(w http.ResponseWriter, r *http.Request) {
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assertJWT(t, r, key)
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w.Header().Set("Content-Type", "application/json")
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switch r.URL.Path {
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case "/aspsps":
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if r.URL.Query().Get("country") != "DE" || r.URL.Query().Get("psu_type") != "personal" {
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t.Error("institution filter missing")
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}
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fmt.Fprint(w, `{"aspsps":[{"name":"N26","country":"DE","maximum_consent_validity":3600}]}`)
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case "/auth":
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if r.Method != "POST" {
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t.Error("wrong auth method")
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}
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var request struct {
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Access struct {
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ValidUntil string `json:"valid_until"`
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Balances bool `json:"balances"`
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Transactions bool `json:"transactions"`
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} `json:"access"`
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State string `json:"state"`
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Redirect string `json:"redirect_url"`
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PSUType string `json:"psu_type"`
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ASPSP institutionDTO `json:"aspsp"`
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}
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if err := json.NewDecoder(r.Body).Decode(&request); err != nil {
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t.Error(err)
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}
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valid, err := time.Parse(time.RFC3339, request.Access.ValidUntil)
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if err != nil || valid.After(time.Now().Add(time.Hour)) || !valid.After(time.Now()) || !request.Access.Balances || !request.Access.Transactions || request.State != "csrf-state" || request.Redirect != "http://localhost:8080/api/banking/callback" || request.PSUType != "personal" || request.ASPSP.Name != "N26" {
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t.Errorf("invalid authorization request: %+v", request)
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}
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fmt.Fprint(w, `{"url":"https://enablebanking.com/auth/consent"}`)
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case "/sessions":
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if r.Method != "POST" {
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t.Error("wrong exchange method")
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}
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var request map[string]string
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if err := json.NewDecoder(r.Body).Decode(&request); err != nil || request["code"] != "secret-code" {
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t.Error("missing exchange code")
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}
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fmt.Fprintf(w, `{"session_id":"session-1","access":{"valid_until":%q},"aspsp":{"name":"N26","country":"DE"},"accounts":[{"uid":"uid-one","identification_hash":"stable-hash","account_id":{"iban":"DE02120300000000202051"},"details":"Main account","currency":"EUR"}]}`, expiry)
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case "/sessions/session-1":
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fmt.Fprintf(w, `{"status":"AUTHORIZED","access":{"valid_until":%q},"aspsp":{"name":"N26","country":"DE"},"accounts":["uid-one"],"accounts_data":[{"uid":"uid-one","identification_hash":"stable-hash"}]}`, expiry)
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case "/accounts/uid-one/details":
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t.Error("session membership must not require account details")
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http.Error(w, "account details unavailable", http.StatusServiceUnavailable)
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case "/accounts/uid-one/balances":
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fmt.Fprint(w, `{"balances":[{"name":"Booked","balance_amount":{"currency":"EUR","amount":"1234.5678"},"balance_type":"CLBD","reference_date":"2026-09-01"}]}`)
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case "/accounts/uid-one/transactions":
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pages++
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q := r.URL.Query()
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if q.Get("transaction_status") != "BOOK" || q.Get("date_from") != "2026-09-01" || q.Get("date_to") != "2026-09-30" {
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t.Error("missing booked/date filters")
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}
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if pages == 1 {
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if q.Get("continuation_key") != "" {
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t.Error("unexpected initial continuation")
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}
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fmt.Fprint(w, `{"transactions":[{"entry_reference":"entry-one","transaction_id":"unstable","transaction_amount":{"amount":"12.3456","currency":"EUR"},"credit_debit_indicator":"DBIT","status":"BOOK","booking_date":"2026-09-01","value_date":"2026-09-02","creditor":{"name":"Cafe"},"creditor_account":{"iban":"DE89370400440532013000"},"remittance_information":["first","second"]},{"transaction_amount":{"amount":"99.00","currency":"EUR"},"credit_debit_indicator":"DBIT","status":"PDNG","booking_date":"2026-09-01"}],"continuation_key":"opaque +/=?token"}`)
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} else {
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if q.Get("continuation_key") != "opaque +/=?token" {
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t.Error("pagination key was not encoded correctly")
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}
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fmt.Fprint(w, `{"transactions":[{"transaction_id":"not-a-stable-id","transaction_amount":{"amount":"20.00","currency":"EUR"},"credit_debit_indicator":"CRDT","status":"BOOK","booking_date":"2026-09-03","debtor":{"name":"Employer"},"debtor_account":{"iban":"DE02120300000000202051"},"remittance_information":["Income"]}],"continuation_key":null}`)
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}
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default:
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t.Errorf("unexpected request %s", r.URL.Path)
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http.NotFound(w, r)
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}
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}
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p, k := testProvider(t, handler)
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key = k
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authorization, err := p.Authorize(context.Background(), "N26", "de", "csrf-state")
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if err != nil || authorization != "https://enablebanking.com/auth/consent" {
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t.Fatalf("authorize: %s %v", authorization, err)
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}
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session, err := p.Exchange(context.Background(), "secret-code")
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if err != nil {
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t.Fatal(err)
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}
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if session.ID != "session-1" || len(session.Accounts) != 1 || session.Accounts[0].IBAN != "DE02120300000000202051" {
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t.Fatalf("incorrect session: %+v", session)
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}
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status, err := p.Status(context.Background(), session.ID)
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if err != nil {
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t.Fatal(err)
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}
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if len(status.AccountIDs) != 1 || status.AccountIDs[0] != session.Accounts[0].ExternalAccountID || status.ValidUntil != expiry {
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t.Fatalf("incorrect consent membership or expiry: %+v", status)
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}
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balances, err := p.Balances(context.Background(), "uid-one")
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if err != nil || len(balances) != 1 || balances[0].Amount.String() != "1234.5678" || balances[0].Type != "CLBD" {
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t.Fatalf("balance precision lost: %+v %v", balances, err)
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}
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transactions, err := p.Transactions(context.Background(), session.Accounts[0], "2026-09-01", "2026-09-30", false)
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if err != nil {
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t.Fatal(err)
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}
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if pages != 2 || len(transactions) != 2 {
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t.Fatalf("booked pagination: pages=%d rows=%d", pages, len(transactions))
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}
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if transactions[0].Amount.String() != "-12.3456" || transactions[0].ExternalID != "entry-one" || transactions[0].Counterparty != "Cafe" || transactions[0].RawDescription != "first\nsecond" || transactions[1].Amount.String() != "20.00" || transactions[1].ExternalID != "" || transactions[1].Counterparty != "Employer" {
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t.Fatalf("wrong booking facts: %+v", transactions)
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}
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}
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func TestEnableBankingFailsClosed(t *testing.T) {
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p, _ := testProvider(t, func(w http.ResponseWriter, r *http.Request) {
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http.Error(w, "secret-account-IBAN private upstream failure", http.StatusUnauthorized)
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})
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_, err := p.Balances(context.Background(), "sensitive-account-identifier")
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if err == nil || strings.Contains(err.Error(), "secret") || strings.Contains(err.Error(), "sensitive") || !strings.Contains(err.Error(), "401") {
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t.Fatalf("unsafe error: %v", err)
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}
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if _, err := p.Status(context.Background(), "session"); err == nil || errors.Is(err, ErrReconnect) {
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t.Fatalf("application HTTP401 conflated with bank consent: %v", err)
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}
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ctx, cancel := context.WithCancel(context.Background())
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cancel()
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if _, err := p.Balances(ctx, "uid"); err == nil {
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t.Fatal("ignored cancellation")
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}
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}
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func TestEnableBankingRejectsPaginationCyclesAndPartialResults(t *testing.T) {
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p, _ := testProvider(t, func(w http.ResponseWriter, r *http.Request) {
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fmt.Fprint(w, `{"transactions":[{"transaction_amount":{"amount":"1.00","currency":"EUR"},"credit_debit_indicator":"CRDT","status":"BOOK","booking_date":"2026-09-01"}],"continuation_key":"same"}`)
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})
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account := fixtureDataset().Accounts[0]
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account.ExternalAccountID = "uid"
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rows, err := p.Transactions(context.Background(), account, "", "", false)
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if err == nil || rows != nil {
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t.Fatal("pagination cycle returned partial import")
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}
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}
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func TestEnableBankingLongestStrategyIsOnlySentWhenRequested(t *testing.T) {
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var strategies []string
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p, _ := testProvider(t, func(w http.ResponseWriter, r *http.Request) {
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strategies = append(strategies, r.URL.Query().Get("strategy"))
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fmt.Fprint(w, `{"transactions":[]}`)
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})
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account := fixtureDataset().Accounts[0]
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account.ExternalAccountID = "uid"
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if _, err := p.Transactions(context.Background(), account, "2020-01-01", "", true); err != nil {
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t.Fatal(err)
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}
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if _, err := p.Transactions(context.Background(), account, "2026-09-01", "2026-09-30", false); err != nil {
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t.Fatal(err)
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}
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if !reflect.DeepEqual(strategies, []string{"longest", ""}) {
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t.Fatalf("wrong fetching strategies requested: %q", strategies)
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}
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}
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func TestEnableBankingSurfacesOnlyDocumentedErrorCodes(t *testing.T) {
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body := ""
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p, _ := testProvider(t, func(w http.ResponseWriter, r *http.Request) {
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w.WriteHeader(http.StatusUnprocessableEntity)
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fmt.Fprint(w, body)
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})
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account := fixtureDataset().Accounts[0]
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account.ExternalAccountID = "uid"
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fetch := func() error {
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_, err := p.Transactions(context.Background(), account, "2020-01-01", "", true)
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return err
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}
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body = `{"code":422,"error":"WRONG_TRANSACTIONS_PERIOD","message":"private-bank-text","detail":"private-account-detail"}`
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err := fetch()
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if err == nil || !strings.Contains(err.Error(), "WRONG_TRANSACTIONS_PERIOD") || !strings.Contains(err.Error(), "422") {
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t.Fatalf("documented period error was hidden: %v", err)
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}
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if strings.Contains(err.Error(), "private") || errors.Is(err, ErrReconnect) {
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t.Fatalf("unsafe or misclassified period error: %v", err)
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}
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body = `{"code":422,"error":"UNDOCUMENTED_PRIVATE_CODE","detail":"secret"}`
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if err = fetch(); err == nil || strings.Contains(err.Error(), "UNDOCUMENTED") || strings.Contains(err.Error(), "secret") || !strings.Contains(err.Error(), "422") {
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t.Fatalf("undocumented provider code leaked: %v", err)
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}
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body = `{"code":404,"error":"SESSION_DOES_NOT_EXIST"}`
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if err = fetch(); !errors.Is(err, ErrReconnect) {
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t.Fatalf("dead session did not request reconnection: %v", err)
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}
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}
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func TestEnableBankingSessionRevocationAndInvalidBookedDates(t *testing.T) {
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p, _ := testProvider(t, func(w http.ResponseWriter, r *http.Request) {
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if strings.HasPrefix(r.URL.Path, "/sessions/") {
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fmt.Fprint(w, `{"status":"REVOKED","accounts":[],"access":{"valid_until":"2099-01-01T00:00:00Z"}}`)
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return
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}
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fmt.Fprint(w, `{"transactions":[{"transaction_amount":{"amount":"1.00","currency":"EUR"},"credit_debit_indicator":"CRDT","status":"BOOK","value_date":"2026-09-01"}]}`)
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})
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if _, err := p.Status(context.Background(), "revoked"); !errors.Is(err, ErrReconnect) {
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t.Fatalf("revoked consent must request reconnection: %v", err)
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}
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account := fixtureDataset().Accounts[0]
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account.ExternalAccountID = "uid"
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rows, err := p.Transactions(context.Background(), account, "", "", false)
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if err == nil || rows != nil {
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t.Fatal("invented booking date for missing bank fact")
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}
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}
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func TestEnableBankingDoesNotFollowRedirects(t *testing.T) {
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leaked := false
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target := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { leaked = true }))
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defer target.Close()
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p, _ := testProvider(t, func(w http.ResponseWriter, r *http.Request) {
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http.Redirect(w, r, target.URL, http.StatusTemporaryRedirect)
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})
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if _, err := p.Balances(context.Background(), "uid"); err == nil || leaked {
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t.Fatalf("followed sensitive banking redirect: leaked=%v error=%v", leaked, err)
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}
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}
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|
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func TestEnableBankingExpiredConsentRequiresReconnect(t *testing.T) {
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p, _ := testProvider(t, func(w http.ResponseWriter, r *http.Request) {
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fmt.Fprint(w, `{"status":"AUTHORIZED","accounts":[],"access":{"valid_until":"2000-01-01T00:00:00Z"}}`)
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})
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if _, err := p.Status(context.Background(), "expired"); !errors.Is(err, ErrReconnect) {
|
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t.Fatalf("expired consent must request reconnection: %v", err)
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}
|
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}
|
|
|
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func TestEnableBankingRejectsInvalidSessionMembership(t *testing.T) {
|
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for name, payload := range map[string]string{
|
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"empty UID": `{"status":"AUTHORIZED","accounts":[""],"access":{"valid_until":"2099-01-01T00:00:00Z"}}`,
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"non-string UID": `{"status":"AUTHORIZED","accounts":[{}],"access":{"valid_until":"2099-01-01T00:00:00Z"}}`,
|
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"invalid expiry": `{"status":"AUTHORIZED","accounts":["uid"],"access":{"valid_until":"not-a-date"}}`,
|
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} {
|
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t.Run(name, func(t *testing.T) {
|
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p, _ := testProvider(t, func(w http.ResponseWriter, r *http.Request) {
|
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fmt.Fprint(w, payload)
|
|
})
|
|
status, err := p.Status(context.Background(), "session")
|
|
if err == nil || status.ValidUntil != "" || status.AccountIDs != nil || errors.Is(err, ErrReconnect) {
|
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t.Fatalf("invalid response returned usable membership or claimed revoked consent: %+v %v", status, err)
|
|
}
|
|
})
|
|
}
|
|
}
|
|
|
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type bankingRoundTripFunc func(*http.Request) (*http.Response, error)
|
|
|
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func (f bankingRoundTripFunc) RoundTrip(r *http.Request) (*http.Response, error) {
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return f(r)
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|
}
|
|
|
|
type bankingClosedBody struct {
|
|
io.ReadCloser
|
|
closed *atomic.Int32
|
|
onClose func()
|
|
}
|
|
|
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func (b *bankingClosedBody) Close() error {
|
|
b.closed.Add(1)
|
|
err := b.ReadCloser.Close()
|
|
if b.onClose != nil {
|
|
b.onClose()
|
|
}
|
|
return err
|
|
}
|
|
|
|
func TestEnableBankingGETRecoversAfterRateLimit(t *testing.T) {
|
|
for _, endpoint := range []string{"status", "transactions"} {
|
|
t.Run(endpoint, func(t *testing.T) {
|
|
t.Parallel()
|
|
var calls, closed atomic.Int32
|
|
var first atomic.Int64
|
|
p, _ := testProvider(t, func(w http.ResponseWriter, r *http.Request) {
|
|
if calls.Add(1) == 1 {
|
|
first.Store(time.Now().UnixNano())
|
|
w.Header().Set("Retry-After", "1")
|
|
http.Error(w, "private provider response", http.StatusTooManyRequests)
|
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return
|
|
}
|
|
if time.Since(time.Unix(0, first.Load())) < time.Second {
|
|
t.Error("retried before provider cooldown elapsed")
|
|
}
|
|
if closed.Load() != 1 {
|
|
t.Error("retried without closing the rate-limit response")
|
|
}
|
|
if endpoint == "status" {
|
|
fmt.Fprint(w, `{"status":"AUTHORIZED","accounts":["uid"],"access":{"valid_until":"2099-01-01T00:00:00Z"}}`)
|
|
} else {
|
|
fmt.Fprint(w, `{"transactions":[{"entry_reference":"entry","transaction_amount":{"amount":"1.00","currency":"EUR"},"credit_debit_indicator":"CRDT","status":"BOOK","booking_date":"2026-09-01"}]}`)
|
|
}
|
|
})
|
|
transport := p.HTTPClient.Transport
|
|
p.HTTPClient.Timeout = 500 * time.Millisecond
|
|
p.HTTPClient.Transport = bankingRoundTripFunc(func(r *http.Request) (*http.Response, error) {
|
|
response, err := transport.RoundTrip(r)
|
|
if err == nil && response.StatusCode == http.StatusTooManyRequests {
|
|
response.Body = &bankingClosedBody{ReadCloser: response.Body, closed: &closed}
|
|
}
|
|
return response, err
|
|
})
|
|
if endpoint == "status" {
|
|
status, err := p.Status(context.Background(), "session")
|
|
if err != nil || len(status.AccountIDs) != 1 || status.AccountIDs[0] != "uid" {
|
|
t.Fatalf("session membership did not recover: %+v %v", status, err)
|
|
}
|
|
} else {
|
|
account := fixtureDataset().Accounts[0]
|
|
account.ExternalAccountID = "uid"
|
|
rows, err := p.Transactions(context.Background(), account, "", "", false)
|
|
if err != nil || len(rows) != 1 || rows[0].ExternalID != "entry" || rows[0].Amount.String() != "1.00" {
|
|
t.Fatalf("transaction retrieval did not recover: %+v %v", rows, err)
|
|
}
|
|
}
|
|
if calls.Load() != 2 || closed.Load() != 1 {
|
|
t.Fatalf("unexpected retry requests or response leaks: calls=%d closed=%d", calls.Load(), closed.Load())
|
|
}
|
|
})
|
|
}
|
|
}
|
|
|
|
func TestEnableBankingCooldownCoversAllEndpoints(t *testing.T) {
|
|
var calls atomic.Int32
|
|
p, _ := testProvider(t, func(w http.ResponseWriter, r *http.Request) {
|
|
calls.Add(1)
|
|
w.Header().Set("Retry-After", "300")
|
|
http.Error(w, "private provider response", http.StatusTooManyRequests)
|
|
})
|
|
_, err := p.Status(context.Background(), "session")
|
|
var initial *ratelimit.RateLimitError
|
|
if !errors.As(err, &initial) || !initial.RetryAt().After(time.Now()) || errors.Is(err, ErrReconnect) || strings.Contains(err.Error(), "private") {
|
|
t.Fatalf("unsafe or missing rate-limit error: %v", err)
|
|
}
|
|
account := fixtureDataset().Accounts[0]
|
|
account.ExternalAccountID = "uid"
|
|
for name, request := range map[string]func() error{
|
|
"status": func() error { _, err := p.Status(context.Background(), "other-session"); return err },
|
|
"balances": func() error { _, err := p.Balances(context.Background(), "uid"); return err },
|
|
"transactions": func() error { _, err := p.Transactions(context.Background(), account, "", "", false); return err },
|
|
"exchange": func() error { _, err := p.Exchange(context.Background(), "once-only-code"); return err },
|
|
"authorize": func() error { _, err := p.Authorize(context.Background(), "N26", "DE", "state"); return err },
|
|
} {
|
|
t.Run(name, func(t *testing.T) {
|
|
err := request()
|
|
var limit *ratelimit.RateLimitError
|
|
if !errors.As(err, &limit) || !limit.RetryAt().Equal(initial.RetryAt()) || errors.Is(err, ErrReconnect) || strings.Contains(err.Error(), "private") {
|
|
t.Fatalf("cooldown was lost or unsafe: %v", err)
|
|
}
|
|
if calls.Load() != 1 {
|
|
t.Fatalf("provider contacted during cooldown: %d requests", calls.Load())
|
|
}
|
|
})
|
|
}
|
|
}
|
|
|
|
func TestEnableBankingNeverReplaysMutationAfterRateLimit(t *testing.T) {
|
|
for _, endpoint := range []string{"exchange", "authorize"} {
|
|
t.Run(endpoint, func(t *testing.T) {
|
|
var posts atomic.Int32
|
|
p, _ := testProvider(t, func(w http.ResponseWriter, r *http.Request) {
|
|
if r.URL.Path == "/aspsps" {
|
|
fmt.Fprint(w, `{"aspsps":[{"name":"N26","country":"DE","maximum_consent_validity":3600}]}`)
|
|
return
|
|
}
|
|
if r.Method != http.MethodPost {
|
|
t.Error("unexpected non-mutation request")
|
|
}
|
|
posts.Add(1)
|
|
w.Header().Set("Retry-After", "1")
|
|
http.Error(w, "private once-only exchange failure", http.StatusTooManyRequests)
|
|
})
|
|
var err error
|
|
if endpoint == "exchange" {
|
|
_, err = p.Exchange(context.Background(), "once-only-code")
|
|
} else {
|
|
_, err = p.Authorize(context.Background(), "N26", "DE", "state")
|
|
}
|
|
var limit *ratelimit.RateLimitError
|
|
if !errors.As(err, &limit) || strings.Contains(err.Error(), "private") || errors.Is(err, ErrReconnect) {
|
|
t.Fatalf("mutation rate limit was lost or unsafe: %v", err)
|
|
}
|
|
if posts.Load() != 1 {
|
|
t.Fatalf("mutation replayed %d times", posts.Load())
|
|
}
|
|
})
|
|
}
|
|
}
|
|
|
|
func TestEnableBankingCanceledRetryRetainsCooldown(t *testing.T) {
|
|
var calls, closed atomic.Int32
|
|
p, _ := testProvider(t, func(w http.ResponseWriter, r *http.Request) {
|
|
calls.Add(1)
|
|
w.Header().Set("Retry-After", "60")
|
|
http.Error(w, "private provider response", http.StatusTooManyRequests)
|
|
})
|
|
ctx, cancel := context.WithCancel(context.Background())
|
|
defer cancel()
|
|
transport := p.HTTPClient.Transport
|
|
p.HTTPClient.Transport = bankingRoundTripFunc(func(r *http.Request) (*http.Response, error) {
|
|
response, err := transport.RoundTrip(r)
|
|
if err == nil && response.StatusCode == http.StatusTooManyRequests {
|
|
response.Body = &bankingClosedBody{ReadCloser: response.Body, closed: &closed, onClose: cancel}
|
|
}
|
|
return response, err
|
|
})
|
|
_, err := p.Status(ctx, "session")
|
|
var original *ratelimit.RateLimitError
|
|
if !errors.Is(err, context.Canceled) || !errors.As(err, &original) || strings.Contains(err.Error(), "private") {
|
|
t.Fatalf("cancellation lost safe rate-limit evidence: %v", err)
|
|
}
|
|
_, err = p.Balances(context.Background(), "uid")
|
|
var retained *ratelimit.RateLimitError
|
|
if !errors.As(err, &retained) || !retained.RetryAt().Equal(original.RetryAt()) {
|
|
t.Fatalf("cancellation discarded provider cooldown: %v", err)
|
|
}
|
|
if calls.Load() != 1 || closed.Load() != 1 {
|
|
t.Fatalf("cancellation retried or leaked a response: calls=%d closed=%d", calls.Load(), closed.Load())
|
|
}
|
|
}
|
|
|
|
func TestEnableBankingPSUSurvivesRetryAndPaginationWithoutLeakingToBackground(t *testing.T) {
|
|
var manualCalls, backgroundCalls atomic.Int32
|
|
psu := PSU{IPAddress: "203.0.113.42", UserAgent: "test-browser", Accept: "application/json", AcceptCharset: "utf-8", AcceptEncoding: "gzip", AcceptLanguage: "de"}
|
|
p, _ := testProvider(t, func(w http.ResponseWriter, r *http.Request) {
|
|
if r.URL.Path == "/accounts/uid/transactions" {
|
|
for name, want := range map[string]string{
|
|
"Psu-Ip-Address": psu.IPAddress, "Psu-User-Agent": psu.UserAgent,
|
|
"Psu-Accept": psu.Accept, "Psu-Accept-Charset": psu.AcceptCharset,
|
|
"Psu-Accept-Encoding": psu.AcceptEncoding, "Psu-Accept-Language": psu.AcceptLanguage,
|
|
} {
|
|
if got := r.Header.Get(name); got != want {
|
|
t.Errorf("%s = %q, want %q", name, got, want)
|
|
}
|
|
}
|
|
switch manualCalls.Add(1) {
|
|
case 1:
|
|
w.WriteHeader(http.StatusTooManyRequests)
|
|
fmt.Fprint(w, `{"error":"ASPSP_RATE_LIMIT_EXCEEDED","detail":"private"}`)
|
|
case 2:
|
|
fmt.Fprint(w, `{"transactions":[],"continuation_key":"next-private-page"}`)
|
|
case 3:
|
|
if r.URL.Query().Get("continuation_key") != "next-private-page" || r.URL.Query().Get("date_from") != "2026-01-01" {
|
|
t.Error("pagination lost original filters or continuation")
|
|
}
|
|
fmt.Fprint(w, `{"transactions":[{"entry_reference":"entry","transaction_amount":{"amount":"1.00","currency":"EUR"},"credit_debit_indicator":"CRDT","status":"BOOK","booking_date":"2026-09-01"}]}`)
|
|
default:
|
|
t.Error("unexpected manual replay")
|
|
}
|
|
return
|
|
}
|
|
backgroundCalls.Add(1)
|
|
for name := range r.Header {
|
|
if strings.HasPrefix(strings.ToLower(name), "psu-") {
|
|
t.Errorf("PSU metadata escaped manual account request: %s", name)
|
|
}
|
|
}
|
|
if r.URL.Path == "/sessions/session" {
|
|
fmt.Fprint(w, `{"status":"AUTHORIZED","accounts":["uid"],"access":{"valid_until":"2099-01-01T00:00:00Z"}}`)
|
|
} else {
|
|
fmt.Fprint(w, `{"balances":[]}`)
|
|
}
|
|
})
|
|
p.requests = ratelimit.Controller{InitialBackoff: time.Millisecond}
|
|
ctx := WithPSU(context.Background(), psu)
|
|
account := fixtureDataset().Accounts[0]
|
|
account.ExternalAccountID = "uid"
|
|
rows, err := p.Transactions(ctx, account, "2026-01-01", "", false)
|
|
if err != nil || len(rows) != 1 || rows[0].ExternalID != "entry" {
|
|
t.Fatalf("manual history failed: %+v %v", rows, err)
|
|
}
|
|
if _, err := p.Balances(context.Background(), "uid"); err != nil {
|
|
t.Fatal(err)
|
|
}
|
|
if _, err := p.Status(ctx, "session"); err != nil {
|
|
t.Fatal(err)
|
|
}
|
|
if manualCalls.Load() != 3 || backgroundCalls.Load() != 2 {
|
|
t.Fatalf("unexpected request counts: manual=%d other=%d", manualCalls.Load(), backgroundCalls.Load())
|
|
}
|
|
}
|
|
|
|
func TestEnableBankingBackgroundQuotaIsScopedAndExpires(t *testing.T) {
|
|
var calls atomic.Int32
|
|
p, _ := testProvider(t, func(w http.ResponseWriter, r *http.Request) {
|
|
if calls.Add(1) == 1 {
|
|
w.WriteHeader(http.StatusTooManyRequests)
|
|
fmt.Fprint(w, `{"error":"ASPSP_RATE_LIMIT_EXCEEDED","message":"private-bank-message"}`)
|
|
return
|
|
}
|
|
if strings.HasSuffix(r.URL.Path, "/transactions") {
|
|
fmt.Fprint(w, `{"transactions":[]}`)
|
|
} else {
|
|
fmt.Fprint(w, `{"balances":[]}`)
|
|
}
|
|
})
|
|
before := time.Now()
|
|
_, err := p.Balances(context.Background(), "uid")
|
|
var first *ratelimit.RateLimitError
|
|
if !errors.As(err, &first) || first.RetryAt().Before(before.Add(6*time.Hour)) || first.RetryAt().After(time.Now().Add(6*time.Hour)) || strings.Contains(err.Error(), "private") || errors.Is(err, ErrReconnect) {
|
|
t.Fatalf("missing safe six-hour bank quota: %v", err)
|
|
}
|
|
var quota *BackgroundQuotaError
|
|
if !errors.As(err, "a) || !quota.RetryAt().Equal(first.RetryAt()) {
|
|
t.Fatalf("background quota identity was lost: %v", err)
|
|
}
|
|
_, err = p.Balances(context.Background(), "uid")
|
|
var retained *ratelimit.RateLimitError
|
|
if !errors.As(err, &retained) || !retained.RetryAt().Equal(first.RetryAt()) || calls.Load() != 1 {
|
|
t.Fatalf("background quota was replayed: calls=%d err=%v", calls.Load(), err)
|
|
}
|
|
if _, err := p.Balances(WithPSU(context.Background(), PSU{IPAddress: "203.0.113.42", UserAgent: "test-browser"}), "uid"); err != nil {
|
|
t.Fatalf("background quota blocked real user: %v", err)
|
|
}
|
|
_, err = p.Balances(context.Background(), "uid")
|
|
if !errors.As(err, "a) || !quota.RetryAt().Equal(first.RetryAt()) || calls.Load() != 2 {
|
|
t.Fatalf("foreground success erased background quota: calls=%d err=%v", calls.Load(), err)
|
|
}
|
|
if _, err := p.Balances(context.Background(), "other-uid"); err != nil {
|
|
t.Fatalf("background quota blocked another account: %v", err)
|
|
}
|
|
account := fixtureDataset().Accounts[0]
|
|
account.ExternalAccountID = "uid"
|
|
if _, err := p.Transactions(context.Background(), account, "", "", false); err != nil {
|
|
t.Fatalf("balance quota blocked transaction endpoint: %v", err)
|
|
}
|
|
// Simulate the stored deadline passing without a six-hour wall-clock wait.
|
|
p.backgroundQuotas["/accounts/uid/balances"] = time.Now().Add(-time.Second)
|
|
if _, err := p.Balances(context.Background(), "uid"); err != nil {
|
|
t.Fatalf("expired quota blocked retrieval: %v", err)
|
|
}
|
|
if calls.Load() != 5 {
|
|
t.Fatalf("unexpected bank replays: %d", calls.Load())
|
|
}
|
|
}
|
|
|
|
func TestEnableBankingBackgroundQuotaPreservesLongerHints(t *testing.T) {
|
|
for _, hint := range []string{"43200", time.Now().Add(24 * time.Hour).UTC().Format(http.TimeFormat), "999999999999999999999999999999999"} {
|
|
t.Run(hint, func(t *testing.T) {
|
|
var calls atomic.Int32
|
|
p, _ := testProvider(t, func(w http.ResponseWriter, r *http.Request) {
|
|
calls.Add(1)
|
|
w.Header().Set("Retry-After", hint)
|
|
w.WriteHeader(http.StatusTooManyRequests)
|
|
fmt.Fprint(w, `{"error":"ASPSP_RATE_LIMIT_EXCEEDED"}`)
|
|
})
|
|
before := time.Now()
|
|
_, err := p.Balances(context.Background(), "uid")
|
|
var limit *ratelimit.RateLimitError
|
|
if !errors.As(err, &limit) || calls.Load() != 1 {
|
|
t.Fatalf("quota replayed or lost: calls=%d err=%v", calls.Load(), err)
|
|
}
|
|
switch hint {
|
|
case "43200":
|
|
if limit.RetryAt().Before(before.Add(12 * time.Hour)) {
|
|
t.Fatal("shortened numeric provider hint")
|
|
}
|
|
case "999999999999999999999999999999999":
|
|
if !limit.RetryAt().IsZero() {
|
|
t.Fatal("overflow became a finite short retry")
|
|
}
|
|
default:
|
|
date, _ := http.ParseTime(hint)
|
|
if !limit.RetryAt().Equal(date) {
|
|
t.Fatal("shortened absolute provider hint")
|
|
}
|
|
}
|
|
})
|
|
}
|
|
}
|
|
|
|
func TestEnableBankingOnlyExactBoundedBankErrorUsesBackgroundQuota(t *testing.T) {
|
|
for name, payload := range map[string]string{
|
|
"message only": `{"error":"OTHER","message":"ASPSP_RATE_LIMIT_EXCEEDED"}`,
|
|
"prefix": `{"error":"ASPSP_RATE_LIMIT_EXCEEDED_OTHER"}`,
|
|
"nested": `{"error":{"code":"ASPSP_RATE_LIMIT_EXCEEDED"}}`,
|
|
"oversized": `{"error":"ASPSP_RATE_LIMIT_EXCEEDED","detail":"` + strings.Repeat("x", 16<<10) + `"}`,
|
|
} {
|
|
t.Run(name, func(t *testing.T) {
|
|
var calls atomic.Int32
|
|
p, _ := testProvider(t, func(w http.ResponseWriter, r *http.Request) {
|
|
calls.Add(1)
|
|
w.Header().Set("Retry-After", "300")
|
|
w.WriteHeader(http.StatusTooManyRequests)
|
|
fmt.Fprint(w, payload)
|
|
})
|
|
_, err := p.Balances(context.Background(), "uid")
|
|
var first *ratelimit.RateLimitError
|
|
if !errors.As(err, &first) || first.RetryAt().After(time.Now().Add(6*time.Minute)) {
|
|
t.Fatalf("unrecognized error used bank quota: %v", err)
|
|
}
|
|
_, err = p.Balances(WithPSU(context.Background(), PSU{IPAddress: "203.0.113.42"}), "other")
|
|
var common *ratelimit.RateLimitError
|
|
if !errors.As(err, &common) || !common.RetryAt().Equal(first.RetryAt()) || calls.Load() != 1 {
|
|
t.Fatalf("generic platform cooldown not shared: calls=%d err=%v", calls.Load(), err)
|
|
}
|
|
})
|
|
}
|
|
}
|
|
|
|
func TestEnableBankingValidatesUploadedCredentials(t *testing.T) {
|
|
_, key := testProvider(t, func(w http.ResponseWriter, r *http.Request) {
|
|
t.Error("credential validation must not call provider")
|
|
})
|
|
pkcs1 := pem.EncodeToMemory(&pem.Block{Type: "RSA PRIVATE KEY", Bytes: x509.MarshalPKCS1PrivateKey(key)})
|
|
der, err := x509.MarshalPKCS8PrivateKey(key)
|
|
if err != nil {
|
|
t.Fatal(err)
|
|
}
|
|
pkcs8 := pem.EncodeToMemory(&pem.Block{Type: "PRIVATE KEY", Bytes: der})
|
|
for _, content := range [][]byte{pkcs1, pkcs8} {
|
|
p, err := NewEnableBanking("test-app", content, "https://finance.example/api/banking/callback")
|
|
if err != nil {
|
|
t.Fatal(err)
|
|
}
|
|
token, err := p.jwt()
|
|
if err != nil {
|
|
t.Fatal(err)
|
|
}
|
|
r := httptest.NewRequest(http.MethodGet, "/", nil)
|
|
r.Header.Set("Authorization", "Bearer "+token)
|
|
assertJWT(t, r, key)
|
|
}
|
|
weak, err := rsa.GenerateKey(rand.Reader, 1024)
|
|
if err != nil {
|
|
t.Fatal(err)
|
|
}
|
|
for name, content := range map[string][]byte{
|
|
"invalid": []byte("secret-invalid-key"),
|
|
"oversized": bytes.Repeat([]byte("k"), MaxPrivateKeyPEM+1),
|
|
"multiple": append(append([]byte{}, pkcs1...), pkcs8...),
|
|
"prefix": append([]byte("secret-prefix\n"), pkcs1...),
|
|
"weak": pem.EncodeToMemory(&pem.Block{Type: "RSA PRIVATE KEY", Bytes: x509.MarshalPKCS1PrivateKey(weak)}),
|
|
} {
|
|
t.Run(name, func(t *testing.T) {
|
|
if _, err := NewEnableBanking("test-app", content, "https://finance.example/api/banking/callback"); err == nil || strings.Contains(err.Error(), "secret") {
|
|
t.Fatal("invalid PEM accepted or leaked")
|
|
}
|
|
})
|
|
}
|
|
for _, appID := range []string{"", "app one", "app\none", "app\u007fone", strings.Repeat("a", 257)} {
|
|
if _, err := NewEnableBanking(appID, pkcs1, "https://finance.example/api/banking/callback"); err == nil {
|
|
t.Fatal("invalid app ID accepted")
|
|
}
|
|
}
|
|
for _, redirect := range []string{
|
|
"https://finance.example/", "https://finance.example/api/banking/callback?secret=value",
|
|
"https://finance.example/api/banking/callback#", "https://finance.example/api/banking/callback?",
|
|
"https://user:secret@finance.example/api/banking/callback", "ftp://finance.example/api/banking/callback",
|
|
"https://finance.example/api/banking/%63allback", "https:///api/banking/callback",
|
|
} {
|
|
if _, err := NewEnableBanking("test-app", pkcs1, redirect); err == nil || strings.Contains(err.Error(), "secret") {
|
|
t.Fatal("invalid callback accepted or leaked")
|
|
}
|
|
}
|
|
}
|