ASIHTTPRequest and ASIWebPageRequest loading local html file error - iphone

Question

I'm trying to use the ASIWebPageRequest to load a local html file so that I can use the built-in caching in ASIWebPageRequest. I know this might sound a bit pointless however I want to use remote images in my local files that only get updated once a week or so. If that makes sense.
Here is what I'm doing in code:
//OUTPUT: file:///Users/ledixonuk/Library/Application%20Support/iPhone%20Simulator/4.3.2/Applications/FDF21331-CC80-4ECB-9A33-16AEC073D117/Documents/ItemOne.html
NSURL *fileUrl = [[NSURL alloc] initFileURLWithPath:[FileSystemHelper dataFilePathInDocuments:#"ItemOne.html"]];
// Assume request is a property of our controller
// First, we'll cancel any in-progress page load
[[self webRequest] setDelegate:nil];
[[self webRequest] cancel];
[self setWebRequest:[ASIWebPageRequest requestWithURL:fileUrl]];
[[self webRequest] setDelegate:self];
[[self webRequest] setDidFailSelector:#selector(webPageFailed:)];
[[self webRequest] setDidFinishSelector:#selector(webPageFinished:)];
// Tell the request to replace urls in this page with local urls
//[[self webRequest] setUrlReplacementMode:ASIReplaceExternalResourcesWithLocalURLs];
// Tell the request to embed external resources directly in the page
[[self webRequest] setUrlReplacementMode:ASIReplaceExternalResourcesWithData];
// It is strongly recommended you use a download cache with ASIWebPageRequest
// When using a cache, external resources are automatically stored in the cache
// and can be pulled from the cache on subsequent page loads
[[self webRequest] setDownloadCache:[ASIDownloadCache sharedCache]];
// Ask the download cache for a place to store the cached data
// This is the most efficient way for an ASIWebPageRequest to store a web page
[[self webRequest] setDownloadDestinationPath:[[ASIDownloadCache sharedCache] pathToStoreCachedResponseDataForRequest:[self webRequest]]];
[[self webRequest] startAsynchronous];
And here is the error I'm getting:
404 Not Found
Not Found
The requested URL /Users/ledixonuk/Library/Application Support/iPhone Simulator/4.3.2/Applications/FDF21331-CC80-4ECB-9A33-16AEC073D117/Documents/ItemOne.html was > not found on this server.
Obviously the ASIWebPageRequest can not find the ItemOne.html file in the application document folder, however I've double checked and the file is definitely there.
Has anyone else had a similar issue to this? It's driving me mad trying to sort it out!

Answer 1

ASIWebPageRequest is a subclass of ASIHTTPRequest, and unfortunately ASIHTTPRequest doesn't support fetching file: URLs - only http and https ones.
Basically you have all the code you need, you just need to find a way to plumb it together. You could create a subclass of ASIHTTPRequest that can load file: URLs (essentially provide your own implement of startAsyncronous that instead just calls back the delegates after setting up the right data files), or create a subclass of ASIWebPageRequest that does it. I've not yet thought about it in detail so I have no idea which way would be best.
(I think you're seeing the 404 page as ASIHTTPRequest is managing to contact a web server somewhere - perhaps it's trying to fetch from http://127.0.0.1/Users/ledixonuk/Library/....)

Answer 2

See below the simple implementation I have added to my subclass of ASIHTTPRequest in order to support file:// based URLs. It's by no means complete and possibly missing some properties that should be set and it will not invoke all the delegates but for my own purposes this was enough.
- (void)startRequest
{
if ([url isFileURL])
{
// ASIHTTPRequest does not support handling file:// URLs, this is my own simple implementation here
if ([self isCancelled]) {
return;
}
[self performSelectorOnMainThread:#selector(requestStarted) withObject:nil waitUntilDone:[NSThread isMainThread]];
NSFileManager *fileManager = [[[NSFileManager alloc] init] autorelease];
NSString *filePath = [url path];
BOOL isDirectory = NO;
if ([fileManager fileExistsAtPath:filePath isDirectory:&isDirectory] && !isDirectory)
{
responseStatusCode = 200;
[self setRawResponseData:[NSData dataWithContentsOfFile:filePath]];
[self setContentLength:rawResponseData.length];
[self setTotalBytesRead:[self contentLength]];
}
else
{
responseStatusCode = 404;
[self setContentLength:0];
[self setError:[NSError errorWithDomain:NetworkRequestErrorDomain code:ASIFileManagementError userInfo:[NSDictionary dictionaryWithObjectsAndKeys:[NSString stringWithFormat:#"Cannot open file at path '%#'",filePath],NSLocalizedDescriptionKey,error,NSUnderlyingErrorKey,nil]]];
}
complete = YES;
downloadComplete = YES;
[self requestFinished];
[self markAsFinished];
}
else
{
// let the original implementation deal with all the other URLs
[super startRequest];
}
}