Merge pull request #869 from stripe/bg-better-decoding

Decoding improvements

Stripe/NSDictionary+Stripe.h

@@ -12,12 +12,28 @@ NS_ASSUME_NONNULL_BEGIN
 
 @interface NSDictionary (Stripe)
 
-- (nullable NSDictionary *)stp_dictionaryByRemovingNullsValidatingRequiredFields:(NSArray *)requiredFields;
-
 - (NSDictionary *)stp_dictionaryByRemovingNulls;
 
 - (NSDictionary<NSString *, NSString *> *)stp_dictionaryByRemovingNonStrings;
 
+// Getters
+
+- (nullable NSArray *)stp_arrayForKey:(NSString *)key;
+
+- (BOOL)stp_boolForKey:(NSString *)key or:(BOOL)defaultValue;
+
+- (nullable NSDate *)stp_dateForKey:(NSString *)key;
+
+- (nullable NSDictionary *)stp_dictionaryForKey:(NSString *)key;
+
+- (NSInteger)stp_intForKey:(NSString *)key or:(NSInteger)defaultValue;
+
+- (nullable NSNumber *)stp_numberForKey:(NSString *)key;
+
+- (nullable NSString *)stp_stringForKey:(NSString *)key;
+
+- (nullable NSURL *)stp_urlForKey:(NSString *)key;
+
 @end
 
 NS_ASSUME_NONNULL_END

Stripe/NSDictionary+Stripe.m

@@ -14,19 +14,6 @@
 
 @implementation NSDictionary (Stripe)
 
-- (nullable NSDictionary *)stp_dictionaryByRemovingNullsValidatingRequiredFields:(NSArray *)requiredFields {
-    NSDictionary *result = [self stp_dictionaryByRemovingNulls];
-
-    for (NSString *key in requiredFields) {
-        if (![[result allKeys] containsObject:key]) {
-            // Result missing required field
-            return nil;
-        }
-    }
-
-    return result;
-}
-
 - (NSDictionary *)stp_dictionaryByRemovingNulls {
     NSMutableDictionary *result = [[NSMutableDictionary alloc] init];
 
@@ -66,8 +53,88 @@ - (NSDictionary *)stp_dictionaryByRemovingNulls {
     return [result copy];
 }
 
-@end
+#pragma mark - Getters
+
+- (nullable NSArray *)stp_arrayForKey:(NSString *)key {
+    id value = self[key];
+    if (value && [value isKindOfClass:[NSArray class]]) {
+        return value;
+    }
+    return nil;
+}
+
+- (BOOL)stp_boolForKey:(NSString *)key or:(BOOL)defaultValue {
+    id value = self[key];
+    if (value) {
+        if ([value isKindOfClass:[NSNumber class]]) {
+            return [value boolValue];
+        }
+        if ([value isKindOfClass:[NSString class]]) {
+            NSString *string = [(NSString *)value lowercaseString];
+            // boolValue on NSString is true for "Y", "y", "T", "t", or 1-9
+            if ([string isEqualToString:@"true"] || [string boolValue]) {
+                return YES;
+            }
+            else {
+                return NO;
+            }
+        }
+    }
+    return defaultValue;
+}
+
+- (nullable NSDate *)stp_dateForKey:(NSString *)key {
+    id value = self[key];
+    if (value &&
+        ([value isKindOfClass:[NSNumber class]] || [value isKindOfClass:[NSString class]])) {
+        double timeInterval = [value doubleValue];
+        return [NSDate dateWithTimeIntervalSince1970:timeInterval];
+    }
+    return nil;
+}
 
+- (nullable NSDictionary *)stp_dictionaryForKey:(NSString *)key {
+    id value = self[key];
+    if (value && [value isKindOfClass:[NSDictionary class]]) {
+        return value;
+    }
+    return nil;
+}
+
+- (NSInteger)stp_intForKey:(NSString *)key or:(NSInteger)defaultValue {
+    id value = self[key];
+    if (value &&
+        ([value isKindOfClass:[NSNumber class]] || [value isKindOfClass:[NSString class]])) {
+        return [value integerValue];
+    }
+    return defaultValue;
+}
+
+- (nullable NSDictionary *)stp_numberForKey:(NSString *)key {
+    id value = self[key];
+    if (value && [value isKindOfClass:[NSNumber class]]) {
+        return value;
+    }
+    return nil;
+}
+
+- (nullable NSString *)stp_stringForKey:(NSString *)key {
+    id value = self[key];
+    if (value && [value isKindOfClass:[NSString class]]) {
+        return value;
+    }
+    return nil;
+}
+
+- (nullable NSURL *)stp_urlForKey:(NSString *)key {
+    id value = self[key];
+    if (value && [value isKindOfClass:[NSString class]]) {
+        return [NSURL URLWithString:value];
+    }
+    return nil;
+}
+
+@end
 void linkNSDictionaryCategory(void){}
 
 NS_ASSUME_NONNULL_END

Stripe/PublicHeaders/STPAPIResponseDecodable.h

@@ -14,12 +14,6 @@
  */
 @protocol STPAPIResponseDecodable <NSObject>
 
-/**
- These fields are required to be present in the API response. If any of them are 
- nil, `decodedObjectFromAPIResponse` should also return nil.
- */
-+ (nonnull NSArray *)requiredFields;
-
 /**
  Parses an response from the Stripe API (in JSON format; represented as 
  an `NSDictionary`) into an instance of the class.

Stripe/STPAddress.m

@@ -293,24 +293,21 @@ + (PKAddressField)pkAddressFieldsFromStripeContactFields:(NSSet<STPContactField>
 
 #pragma mark STPAPIResponseDecodable
 
-+ (NSArray *)requiredFields {
-    return @[];
-}
-
 + (instancetype)decodedObjectFromAPIResponse:(NSDictionary *)response {
-    NSDictionary *dict = [response stp_dictionaryByRemovingNullsValidatingRequiredFields:[self requiredFields]];
+    NSDictionary *dict = [response stp_dictionaryByRemovingNulls];
     if (!dict) {
         return nil;
     }
 
     STPAddress *address = [self new];
     address.allResponseFields = dict;
-    address.city = dict[@"city"];
-    address.country = dict[@"country"];
-    address.line1 = dict[@"line1"];
-    address.line2 = dict[@"line2"];
-    address.postalCode = dict[@"postal_code"];
-    address.state = dict[@"state"];
+    /// all properties are nullable
+    address.city = [dict stp_stringForKey:@"city"];
+    address.country = [dict stp_stringForKey:@"country"];
+    address.line1 = [dict stp_stringForKey:@"line1"];
+    address.line2 = [dict stp_stringForKey:@"line2"];
+    address.postalCode = [dict stp_stringForKey:@"postal_code"];
+    address.state = [dict stp_stringForKey:@"state"];
     return address;
 }
 

Stripe/STPBankAccount.m

@@ -115,43 +115,44 @@ - (NSString *)description {
 
 #pragma mark - STPAPIResponseDecodable
 
-+ (NSArray *)requiredFields {
-    return @[
-             @"id",
-             @"last4",
-             @"bank_name",
-             @"country",
-             @"currency",
-             @"status",
-             ];
-}
-
 + (nullable instancetype)decodedObjectFromAPIResponse:(nullable NSDictionary *)response {
-    NSDictionary *dict = [response stp_dictionaryByRemovingNullsValidatingRequiredFields:[self requiredFields]];
+    NSDictionary *dict = [response stp_dictionaryByRemovingNulls];
     if (!dict) {
         return nil;
     }
 
+    // required fields
+    NSString *stripeId = [dict stp_stringForKey:@"id"];
+    NSString *last4 = [dict stp_stringForKey:@"last4"];
+    NSString *bankName = [dict stp_stringForKey:@"bank_name"];
+    NSString *country = [dict stp_stringForKey:@"country"];
+    NSString *currency = [dict stp_stringForKey:@"currency"];
+    NSString *rawStatus = [dict stp_stringForKey:@"status"];
+    if (!stripeId || !last4 || !bankName || !country || !currency || !rawStatus) {
+        return nil;
+    }
+
     STPBankAccount *bankAccount = [self new];
 
     // Identifier
-    bankAccount.stripeID = dict[@"id"];
+    bankAccount.stripeID = stripeId;
 
     // Basic account details
-    bankAccount.routingNumber = dict[@"routing_number"];
-    bankAccount.last4 = dict[@"last4"];
+    bankAccount.routingNumber = [dict stp_stringForKey:@"routing_number"];
+    bankAccount.last4 = last4;
 
     // Additional account details (alphabetical)
-    bankAccount.bankName = dict[@"bank_name"];
-    bankAccount.country = dict[@"country"];
-    bankAccount.currency = dict[@"currency"];
-    bankAccount.fingerprint = dict[@"fingerprint"];
-    bankAccount.metadata = [dict[@"metadata"] stp_dictionaryByRemovingNonStrings];
-    bankAccount.status = [self statusFromString:dict[@"status"]];
+    bankAccount.bankName = bankName;
+    bankAccount.country = country;
+    bankAccount.currency = currency;
+    bankAccount.fingerprint = [dict stp_stringForKey:@"fingerprint"];
+    bankAccount.metadata = [[dict stp_dictionaryForKey:@"metadata"] stp_dictionaryByRemovingNonStrings];
+    bankAccount.status = [self statusFromString:rawStatus];
 
     // Owner details
-    bankAccount.accountHolderName = dict[@"account_holder_name"];
-    bankAccount.accountHolderType = [STPBankAccountParams accountHolderTypeFromString:dict[@"account_holder_type"]];
+    bankAccount.accountHolderName = [dict stp_stringForKey:@"account_holder_name"];
+    NSString *rawAccountHolderType = [dict stp_stringForKey:@"account_holder_type"];
+    bankAccount.accountHolderType = [STPBankAccountParams accountHolderTypeFromString:rawAccountHolderType];
 
     bankAccount.allResponseFields = dict;
 

Stripe/STPCard.m

@@ -169,44 +169,51 @@ - (NSString *)stripeObject {
     return @"card";
 }
 
-+ (NSArray *)requiredFields {
-    return @[@"id", @"last4", @"brand", @"exp_month", @"exp_year"];
-}
-
 + (nullable instancetype)decodedObjectFromAPIResponse:(nullable NSDictionary *)response {
-    NSDictionary *dict = [response stp_dictionaryByRemovingNullsValidatingRequiredFields:[self requiredFields]];
+    NSDictionary *dict = [response stp_dictionaryByRemovingNulls];
     if (!dict) {
         return nil;
     }
 
+    // required fields
+    NSString *stripeId = [dict stp_stringForKey:@"id"];
+    NSString *last4 = [dict stp_stringForKey:@"last4"];
+    NSString *rawBrand = [dict stp_stringForKey:@"brand"];
+    NSNumber *rawExpMonth = [dict stp_numberForKey:@"exp_month"];
+    NSNumber *rawExpYear = [dict stp_numberForKey:@"exp_year"];
+    if (!stripeId || !last4 || !rawBrand || !rawExpMonth || !rawExpYear) {
+        return nil;
+    }
+
     STPCard *card = [self new];
     card.address = [STPAddress new];
 
-    card.stripeID = dict[@"id"];
-    card.name = dict[@"name"];
-    card.last4 = dict[@"last4"];
-    card.dynamicLast4 = dict[@"dynamic_last4"];
-    card.brand = [self.class brandFromString:dict[@"brand"]];
+    card.stripeID = stripeId;
+    card.name = [dict stp_stringForKey:@"name"];
+    card.last4 = last4;
+    card.dynamicLast4 = [dict stp_stringForKey:@"dynamic_last4"];
+    card.brand = [self.class brandFromString:rawBrand];
 #pragma clang diagnostic push
 #pragma clang diagnostic ignored "-Wdeprecated"
     // This is only intended to be deprecated publicly.
     // When removed from public header, can remove these pragmas
-    card.funding = [self.class fundingFromString:dict[@"funding"]];
+    NSString *rawFunding = [dict stp_stringForKey:@"funding"];
+    card.funding = [self.class fundingFromString:rawFunding];
 #pragma clang diagnostic pop
 
-    card.country = dict[@"country"];
-    card.currency = dict[@"currency"];
-    card.expMonth = [dict[@"exp_month"] intValue];
-    card.expYear = [dict[@"exp_year"] intValue];
-    card.metadata = [dict[@"metadata"] stp_dictionaryByRemovingNonStrings];
+    card.country = [dict stp_stringForKey:@"country"];
+    card.currency = [dict stp_stringForKey:@"currency"];
+    card.expMonth = [dict stp_intForKey:@"exp_month" or:0];
+    card.expYear = [dict stp_intForKey:@"exp_year" or:0];
+    card.metadata = [[dict stp_dictionaryForKey:@"metadata"] stp_dictionaryByRemovingNonStrings];
 
     card.address.name = card.name;
-    card.address.line1 = dict[@"address_line1"];
-    card.address.line2 = dict[@"address_line2"];
-    card.address.city = dict[@"address_city"];
-    card.address.state = dict[@"address_state"];
-    card.address.postalCode = dict[@"address_zip"];
-    card.address.country = dict[@"address_country"];
+    card.address.line1 = [dict stp_stringForKey:@"address_line1"];
+    card.address.line2 = [dict stp_stringForKey:@"address_line2"];
+    card.address.city = [dict stp_stringForKey:@"address_city"];
+    card.address.state = [dict stp_stringForKey:@"address_state"];
+    card.address.postalCode = [dict stp_stringForKey:@"address_zip"];
+    card.address.country = [dict stp_stringForKey:@"address_country"];
 
     card.allResponseFields = dict;
     return card;