--- /dev/null
+/*
+ * Copyright 2017 Google
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#import "NSDictionary+FIRMessaging.h"
+
+@implementation NSDictionary (FIRMessaging)
+
+- (NSString *)fcm_string {
+ NSMutableString *dictAsString = [NSMutableString string];
+ NSString *separator = @"|";
+ for (id key in self) {
+ id value = self[key];
+ if ([key isKindOfClass:[NSString class]] && [value isKindOfClass:[NSString class]]) {
+ [dictAsString appendFormat:@"%@:%@%@", key, value, separator];
+ }
+ }
+ // remove the last separator
+ if ([dictAsString length]) {
+ [dictAsString deleteCharactersInRange:NSMakeRange(dictAsString.length - 1, 1)];
+ }
+ return [dictAsString copy];
+}
+
+- (BOOL)fcm_hasNonStringKeysOrValues {
+ for (id key in self) {
+ id value = self[key];
+ if (![key isKindOfClass:[NSString class]] || ![value isKindOfClass:[NSString class]]) {
+ return YES;
+ }
+ }
+ return NO;
+}
+
+- (NSDictionary *)fcm_trimNonStringValues {
+ NSMutableDictionary *trimDictionary =
+ [NSMutableDictionary dictionaryWithCapacity:self.count];
+ for (id key in self) {
+ id value = self[key];
+ if ([key isKindOfClass:[NSString class]] && [value isKindOfClass:[NSString class]]) {
+ trimDictionary[(NSString *)key] = value;
+ }
+ }
+ return trimDictionary;
+}
+
+@end