Implemented MIMETypeForPathExtension for NSURL and NSString. refs #409

Refactored duplicated code for returning the MIME Type based on file path extension using
Core Services UTI.

Code/CoreData/RKManagedObjectSeeder.m

@@ -32,7 +32,6 @@
 #define RKLogComponent lcl_cRestKitCoreData
 
 @interface RKManagedObjectSeeder (Private)
-- (NSString *)mimeTypeForExtension:(NSString *)extension;
 - (id)initWithObjectManager:(RKObjectManager*)manager;
 - (void)seedObjectsFromFileNames:(NSArray*)fileNames;
 @end
@@ -122,7 +121,7 @@ NSString* const RKDefaultSeedDatabaseFileName = @"RKSeedDatabase.sqlite";
 	NSString* payload = [NSString stringWithContentsOfFile:filePath encoding:NSUTF8StringEncoding error:&error];
     
 	if (payload) {
-        NSString* MIMEType = [self mimeTypeForExtension:[fileName pathExtension]];
+        NSString* MIMEType = [fileName MIMETypeForPathExtension];
         if (MIMEType == nil) {
             // Default the MIME type to the value of the Accept header if we couldn't detect it...
             MIMEType = _manager.acceptMIMEType;
@@ -180,21 +179,4 @@ NSString* const RKDefaultSeedDatabaseFileName = @"RKSeedDatabase.sqlite";
 	exit(1);
 }
 
-- (NSString *)mimeTypeForExtension:(NSString *)extension {
-	if (NULL != UTTypeCreatePreferredIdentifierForTag) {
-		CFStringRef uti = UTTypeCreatePreferredIdentifierForTag(kUTTagClassFilenameExtension, (CFStringRef)extension, NULL);
-		if (uti != NULL) {
-			CFStringRef mime = UTTypeCopyPreferredTagWithClass(uti, kUTTagClassMIMEType);
-			CFRelease(uti);
-			if (mime != NULL) {
-				NSString *type = [NSString stringWithString:(NSString *)mime];
-				CFRelease(mime);
-				return type;
-			}
-		}
-	}
-	
-    return nil;
-}
-
 @end

Code/Network/RKParamsAttachment.m

@@ -18,13 +18,11 @@
 //  limitations under the License.
 //
 
-#if TARGET_OS_IPHONE
-#import <MobileCoreServices/UTType.h>
-#endif
 #import "RKParamsAttachment.h"
 #import "RKLog.h"
 #import "NSData+MD5.h"
 #import "FileMD5Hash.h"
+#import "../Support/NSString+RestKit.h"
 
 // Set Logging Component
 #undef RKLogComponent
@@ -35,10 +33,6 @@
  */
 extern NSString* const kRKStringBoundary;
 
-@interface RKParamsAttachment (Private)
-- (NSString *)mimeTypeForExtension:(NSString *)extension;
-@end
-
 @implementation RKParamsAttachment
 
 @synthesize filePath = _filePath;
@@ -88,7 +82,9 @@ extern NSString* const kRKStringBoundary;
 		NSAssert1([[NSFileManager defaultManager] fileExistsAtPath:filePath], @"Expected file to exist at path: %@", filePath);
         _filePath = [filePath retain];
         _fileName = [[filePath lastPathComponent] retain];
-		_MIMEType = [[self mimeTypeForExtension:[filePath pathExtension]] retain];
+        NSString *MIMEType = [filePath MIMETypeForPathExtension];
+        if (! MIMEType) MIMEType = @"application/octet-stream";        
+		_MIMEType = [MIMEType retain];
 		_bodyStream = [[NSInputStream alloc] initWithFileAtPath:filePath];
 		
 		NSError* error;
@@ -125,23 +121,6 @@ extern NSString* const kRKStringBoundary;
 	return kRKStringBoundary;
 }
 
-- (NSString *)mimeTypeForExtension:(NSString *)extension {
-	if (NULL != UTTypeCreatePreferredIdentifierForTag) {
-		CFStringRef uti = UTTypeCreatePreferredIdentifierForTag(kUTTagClassFilenameExtension, (CFStringRef)extension, NULL);
-		if (uti != NULL) {
-			CFStringRef mime = UTTypeCopyPreferredTagWithClass(uti, kUTTagClassMIMEType);
-			CFRelease(uti);
-			if (mime != NULL) {
-				NSString *type = [NSString stringWithString:(NSString *)mime];
-				CFRelease(mime);
-				return type;
-			}
-		}
-	}
-	
-    return @"application/octet-stream";
-}
-
 #pragma mark NSStream methods
 
 - (void)open {

Code/Support/NSString+RestKit.h

@@ -106,4 +106,15 @@
  */
 - (NSString *)stringByReplacingURLEncoding;
 
+/**
+ Interprets the receiver as a path and returns the MIME Type for the path extension 
+ using Core Services.
+ 
+ For example, given a string with the path /Users/blake/Documents/monkey.json we would get 
+ @"application/json" as the MIME Type.
+ 
+ @return The expected MIME Type of the resource identified by the path or nil if unknown
+ */
+- (NSString *)MIMETypeForPathExtension;
+
 @end

Code/Support/NSString+RestKit.m

@@ -18,6 +18,11 @@
 //  limitations under the License.
 //
 
+#if TARGET_OS_MAC
+#import <CoreServices/CoreServices.h>
+#elif TARGET_OS_IPHONE
+#import <MobileCoreServices/UTType.h>
+#endif
 #import "NSString+RestKit.h"
 #import "../Network/RKClient.h"
 #import "RKFixCategoryBug.h"
@@ -112,4 +117,19 @@ RK_FIX_CATEGORY_BUG(NSString_RestKit)
     return [self stringByReplacingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
 }
 
+- (NSString *)MIMETypeForPathExtension {
+    CFStringRef uti = UTTypeCreatePreferredIdentifierForTag(kUTTagClassFilenameExtension, (CFStringRef)[self pathExtension], NULL);
+    if (uti != NULL) {
+        CFStringRef mime = UTTypeCopyPreferredTagWithClass(uti, kUTTagClassMIMEType);
+        CFRelease(uti);
+        if (mime != NULL) {
+            NSString *type = [NSString stringWithString:(NSString *)mime];
+            CFRelease(mime);
+            return type;
+        }
+    }
+	
+    return nil;
+}
+
 @end

Code/Support/NSURL+RestKit.h

@@ -27,4 +27,15 @@
  */
 - (NSDictionary *)queryDictionary;
 
+/**
+ Returns the MIME Type for the resource identified by the URL by interpretting the
+ path extension using Core Services.
+ 
+ For example, given a URL to http://restkit.org/monkey.json we would get 
+ @"application/json" as the MIME Type.
+ 
+ @return The expected MIME Type of the resource identified by the URL or nil if unknown
+ */
+- (NSString *)MIMETypeForPathExtension;
+
 @end

Code/Support/NSURL+RestKit.m

@@ -21,6 +21,7 @@
 #import "NSURL+RestKit.h"
 #import "NSDictionary+RKAdditions.h"
 #import "RKFixCategoryBug.h"
+#import "NSString+RestKit.h"
 
 RK_FIX_CATEGORY_BUG(NSURL_RestKit)
 
@@ -30,4 +31,8 @@ RK_FIX_CATEGORY_BUG(NSURL_RestKit)
     return [NSDictionary dictionaryWithURLEncodedString:self.query];
 }
 
+- (NSString *)MIMETypeForPathExtension {
+    return [[self path] MIMETypeForPathExtension];
+}
+
 @end

Specs/Network/RKURLSpec.m

@@ -3,7 +3,7 @@
 //  RestKit
 //
 //  Created by Blake Watters on 6/29/11.
-//  Copyright 2011 Two Toasters
+//  Copyright 2011 RestKit
 //  
 //  Licensed under the Apache License, Version 2.0 (the "License");
 //  you may not use this file except in compliance with the License.
@@ -20,6 +20,7 @@
 
 #import "RKSpecEnvironment.h"
 #import "RKURL.h"
+#import "NSURL+RestKit.h"
 
 @interface RKURLSpec : RKSpec
 @end
@@ -80,5 +81,10 @@
     assertThat([URL absoluteString], is(equalTo(@"http://restkit.org/test/")));    
 }
 
+- (void)itShouldReturnTheMIMETypeForURL {
+    NSURL *URL = [NSURL URLWithString:@"http://restkit.org/path/to/resource.xml"];
+    assertThat([URL MIMETypeForPathExtension], is(equalTo(@"application/xml")));
+}
+
 @end
  

Specs/Support/NSStringRestKitSpec.m

@@ -70,4 +70,9 @@
     assertThat(queryParams, hasEntries(@"keyA", @"valA", @"keyB", @"valB", nil));
 }
 
+- (void)itShouldReturnTheMIMETypeForAPath {
+    NSString *MIMEType = [@"/path/to/file.xml" MIMETypeForPathExtension];
+    assertThat(MIMEType, is(equalTo(@"application/xml")));
+}
+
 @end