// Handles POST for /verify
func (validator accountValidator) AccountValidatorPost(w http.ResponseWriter, req *http.Request) {
var transformedRequest bankAccountRequest
// Decode the JSON payload
if err := json.NewDecoder(req.Body).Decode(&transformedRequest); err != nil {
responses.WriteUnprocessableEntity(w)
return
}
// Check that we got an expected format
if !transformedRequest.isValid() {
message := "Expected a 6 digits sort code and an account number between 6 and 10 digits."
responses.WriteMessage(http.StatusBadRequest, "invalid_bank_account", message, w)
return
}
// Create the required bank account
b := models.CreateBankAccount(transformedRequest.SortCode, transformedRequest.AccountNumber)
// Check if the bank account is valid
isValid := validator.resolver.IsValid(b)
// Construct and render the final response
response := ValidityResponse{
Valid: isValid,
SortCode: b.SortCode,
AccountNumber: b.AccountNumber,
}
render.JSON(w, http.StatusOK, response)
}
// The middleware handler
func (l *Limiter) ServeHTTP(w http.ResponseWriter, req *http.Request, next http.HandlerFunc) {
apiKey := req.Header.Get("Api-Key")
// Here, in real life, we would typically create a limiter
// based on information from the given API key
hasher := speedbump.PerMinuteHasher{}
limiter := speedbump.NewLimiter(l.redisConnexion, hasher, 5)
canAccess, err := limiter.Attempt(apiKey)
// Trouble with Redis?
if err != nil {
respondRedisError(w)
return
}
// Over the rate limit?
if !canAccess {
responses.WriteMessage(429, "rate_exceeded", "API rate exceeded. Too many requests.", w)
return
}
requestsLeft, err := limiter.Left(apiKey)
// Trouble with Redis?
if err != nil {
respondRedisError(w)
return
}
// Add the number of remaining request as a header
w.Header().Set("Api-Remaining", strconv.Itoa(int(requestsLeft)))
// Call the next middleware handler
next(w, req)
}
// Say that we got an error contacting Redis
func respondRedisError(w http.ResponseWriter) {
responses.WriteMessage(http.StatusInternalServerError, "server_error", "Trouble contacting Redis. Aborting.", w)
return
}