When I load my app I download around 10-15 JSON files and store them into my apps documents directory-- some range from a few KBs to 30MB.
Once that is finished, I need to grab each of them from the documents dir, convert to a NSDictionary, and parse into NSManagedObjects.
But, when I do that with the code below, as it goes though each JSON it seems to keep them in memory, until the app ends up crashing. Instruments shows nothing in the 'Leaks' tool, but my app is keeping a ton in memory.
Heres the code that grabs the JSON files:
UPDATED
- (void)parseDownloadedFiles
{
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *docDir = [paths objectAtIndex:0];
docDir = [docDir stringByAppendingString:#"/jsons"];
NSFileManager *fileManager = [NSFileManager defaultManager];
NSError *error;
NSArray *files = [fileManager contentsOfDirectoryAtPath:docDir error:&error];
if (files == nil) {
// error...
}
for (NSString *file in files)
{
NSString *fileName = [NSString stringWithFormat:#"%#/jsons/%#",
docDir, file];
NSString *content = [[NSString alloc] initWithContentsOfFile:fileName
usedEncoding:nil
error:nil];
NSDictionary *JSON =
[NSJSONSerialization JSONObjectWithData: [content dataUsingEncoding:NSUTF8StringEncoding]
options: NSJSONReadingMutableContainers
error: &error];
...create my NSManagedObjects & store
JSON = nil;
}
}
--
Heres a look at my allocations:
--
Drilling into that first Malloc 44.79 brings shows me these problem lines:
--
This is within the for loop in the code above
Would that NSLog really cause such an issue?
You should put #autoreleasepool {} inside that loop where you read the file. The objects are not being released until the method returns, so the memory will build up inside the loop.
ARC will help you by autoreleasing the objects but you need them to release faster.
https://developer.apple.com/library/mac/#documentation/Cocoa/Conceptual/MemoryMgmt/Articles/mmAutoreleasePools.html
Yep, your getContentFromFile... method is returning a retained string. And you never release it on the receiving end.
You need to either autorelease the string when you return it or explicitly release if after you've parsed it into JSON.
(I'd think Analyzer would have found this.)
Related
I am creating an application. I am storing the files in Document directory. And after my work completed, delete the files from document directory as like below:
NSMutableDictionary * Dictionary = [NSMutableDictionary alloc]init];
// Next every file storing into this dictionary like below
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *baseDir = [paths objectAtIndex:0];
NSString *pathComp = [baseDir stringByAppendingPathComponent:[NSString stringWithFormat:#"IMG%d.PNG",presentCount];
fileURL = [NSURL fileURLWithPath:pathComp];
[Dictionary setObject:fileURL forKey:fileURL];
while ([[Dictionary allKeys]count]!=0) {
NSURL *deleteFileURL = [[Dictionary allKeys] lastObject];
NSLog(#"Path %#",deleteFileURL.path);
[[NSFileManager defaultManager] removeItemAtPath:deleteFileURL.path error:nil];
[Dictionary removeObjectForKey:deleteFileURL];
}
Here my problem is, after delete the files from document directory, memory is not reduced, still it's occupying as like files exist. Due to this issue, my is crashing. So please help me how to clear the memory.
Actually i am getting the files(Photos ) from the server and first placing in documents directory,and trying to save using photo library.Once i give input from dictionary to photo library, after completion handler, i am trying to delete the file.Its removed and photo saved, but memory is not reduced.
1、Remove the file after checking for the existence of a file on the path, and check the return value of removeItemAtPath: to determine if the deletion succeeded.
NSString *path = #"a/b";
if ([[NSFileManager defaultManager] fileExistsAtPath:path]) {
BOOL success = [[NSFileManager defaultManager] removeItemAtPath:path error:nil];
// Check the success's value
}
I have created a custom property list file. The file is stored in the application document.
While user login is successful the login information is stored in the plist, and it is working fine.
The plist content are cleared while log out, this also works fine.
When i am still login i killed the application. When the app opens the plist data i cleared.
code used to save to file:
NSArray *paths = NSSearchPathForDirectoriesInDomains (NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsPath = [paths objectAtIndex:0];
NSString *plistPath = [documentsPath stringByAppendingPathComponent:#"xxxxPlist.plist"];
if (![[NSFileManager defaultManager] fileExistsAtPath:plistPath])
{
plistPath = [[NSBundle mainBundle] pathForResource:#"xxxxPlist" ofType:#"plist"];
}
dict=[[self cleanDictionary:[dict mutableCopy]] mutableCopy];
NSDictionary *plistDict=[[NSDictionary alloc] initWithObjectsAndKeys:dict,#"login_data", nil];
NSError *error = nil;
NSData *plistData = [NSPropertyListSerialization dataWithPropertyList:plistDict format:NSPropertyListXMLFormat_v1_0 options:NSPropertyListImmutable error:&error];
if(plistData)
{
[plistData writeToFile:plistPath atomically:YES];
}
else
{
//error here
NSLog(#"%# ",error);
}
code used to fetch data
NSArray *paths = NSSearchPathForDirectoriesInDomains (NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsPath = [paths objectAtIndex:0];
NSString *plistPath = [documentsPath stringByAppendingPathComponent:#"xxxx.plist"];
if (![[NSFileManager defaultManager] fileExistsAtPath:plistPath])
{
plistPath = [[NSBundle mainBundle] pathForResource:#"xxxxPlist" ofType:#"plist"];
}
NSDictionary *dict = [[NSDictionary alloc] initWithContentsOfFile:plistPath];
return [dict objectForKey:#"login_data"];
I there any way out to persist the data?
There are several things that may be causing problems
When saving to file
1) My understanding is that you specifically want to save to /Documents folder specifically to ensure your file persists
2) So you correctly build following path
"/Documents/xxxxPlist.plist"
3) But then why do you check if a file already exists at that location?
if (![[NSFileManager defaultManager] fileExistsAtPath:plistPath])
{
plistPath = [[NSBundle mainBundle] pathForResource:#"xxxxPlist" ofType:#"plist"];
}
You just have to write to the path when you are ready.
If there is an old file at this location it will be overwritten.
And my understanding is this is the wanted behaviour, because you've already read that file and the data is in that dictionary "dict".
4) Also, by asking NSBundle to give you path for your file name
"xxxxPlist.plist"
there is a risk that it will just give you back some other path with file named the same (not in /Documents) if such file happens to exist. For example if you happened to write to say, /Cache folder earlier (with different code), your app will keep getting the /Cache path and keep reading/writong there (not in /Documents). And with the existing code you would have gotten nil here for path on the very first run, so not sure how he file got created in the first place.
5) Then I am not sure what exactly does this line
dict=[[self cleanDictionary:[dict mutableCopy]] mutableCopy];
Why first make a mutable copy, then presumably get immutable copy back and get a mutable one of it. Can't -cleanDictionary: just return the same mutable copy it was passed?
When reading from file
1) Not sure why you're searching for a different file first?
"/Documents/xxxx.plist" not "/Documents/xxxxPlist.plist"
Also what happens if "xxxx.plist" exists, then you'll never get to "xxxxPlist.plist" that you are writing in the other section.
2) Then, yes, you have to check if a file exists at certain path before you try to read it. But, in your case, if it does not exist, you don't ask NSBundle for another location, because you need your specific file in /Documents, and you don't know what you'll get from NSBundle, if your file is not where it should be.
So if there is no "xxxxPlist.plist" file, it's just your first run of the app and you will be creating your initial dict.
I'm loading a file to a NSMutableArray. I'm doing it like this:
if(!self.dataArray){
self.dataArray = [[NSMutableArray alloc] init];
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory,
NSUserDomainMask, YES);
NSString *arrayPath = [[paths objectAtIndex:0]
stringByAppendingPathComponent:#"array.out"];
self.dataArray = [NSMutableArray arrayWithContentsOfFile:arrayPath];
}
The array that is loaded into the file consists of multiple NSDictionaries.
However, this somehow deallocates the array in the memory because when I log dataArray after doing this, it logs nil. How come?
Update
I've figured out that [NSMutableArray arrayWithContentsOfFile:arrayPath] is logging nil because the code in which I'm uploading the content to the file, doesn't create the file:
// write data to disk
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *arrayPath = [[paths objectAtIndex:0]stringByAppendingPathComponent:#"array.out"];
[self.dataArray writeToFile:arrayPath atomically:YES];
NSLog(#"uploaded file: %#", arrayPath); // logs an arrayPath, but one that doesn't exists.
Check the following,
Check the dataArray is a weak property ? If so, change to strong.
Check the file exists at path, using
[[NSFileManager defaultManager] fileExistsAtPath:arrayPath];
Verify the file have expected content, by logging it.
Confirm the File content is organized as a property list (plist). Verify it in plist editor/Xcode.
If you dynamically creating it, check the path you are writing to.
Confirm the method of writing NSArray to plist. Use
[array writeToFile:path atomically:YES];
Note:
If you are dynamically creating the file and you are testing on Simulator; you can
find the file by logging file path and following it on Finder.
Property List Reference
Apple documentation
Per Apple documentation, the array returns nil if the file can’t be opened or if the contents of the file can’t be parsed into an array.
Did you use the [writeToFile:atomically:] method to write the array to a file?
Also, make sure that the filePath string matches exactly on both write and read ends. I've wasted a lot of time trying to hunt down a bug when it turned out I had misspelled the name of the file or used the wrong file extension.
Another possibility: have you confirmed that this code is being executed? Sometimes I've had to change (!self.someProperty) to (self.someProperty != nil) in my if condition to get code like this to run.
Peter Segerblom and wildBillMunson are right: the array returns nil if the file can't be opened or if its content can't be parsed into an array.
You said "array.out" is an array of NSDictionaries. Whenever I have that set of data, I use the plist type of file and read it this way:
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSApplicationSupportDirectory, NSUserDomainMask, YES);
NSString *directory = [paths objectAtIndex:0];
NSString *fullPath = [directory stringByAppendingPathComponent:#"data.plist"];
NSString *errorDesc = nil;
NSPropertyListFormat format;
NSData *plistXML = [[NSFileManager defaultManager] contentsAtPath:fullPath];
NSArray *data = (NSArray *)[NSPropertyListSerialization propertyListFromData:plistXML mutabilityOption:NSPropertyListMutableContainersAndLeaves format:&format errorDescription:&errorDesc];
Be sure to check if fullPath is not returning nil.
Hope this helps!
I have a web server, running locally, which serves JSON-formatted data from a number of endpoints. I currently include the data from each endpoint in separate .json files, which I manually add to the app bundle for use within the app. Is it possible to automate this process whenever the project is built, perhaps using an Xcode build script?
Below is an example of what I am trying to achieve.
Fetch the JSON-formatted data from localhost:3000/example.
Stop here if the endpoint cannot be reached.
Save the data in a file called example.json.
Add example.json to the app bundle for use within the app.
Any help with this would be greatly appreciated.
Edit
I have fetched the JSON-formatted data, however I am now looking to see how this data can be copied into the app bundle.
curl -o example.json http://localhost:3000/example
Here's how I did the same thing in my project.
I went to my target -> Build Phases -> + -> 'New Run Script Phase' and added the following script:
curl -o ${BUILT_PRODUCTS_DIR}/${PRODUCT_NAME}.app/your_file.json http://localhost:3000/your_file.json
echo "Your file downloaded to ${BUILT_PRODUCTS_DIR}/${PRODUCT_NAME}.app/your_file.json"
I am currently working on adding some validation to the process, but as a starting point this is working for me.
Hope that helps!
UPDATE
Here is the same code with some added JSON validation:
YOUR_DATA=$(curl -s "http://localhost:3000/your_file.json" | python -m json.tool);
if [ -n "$YOUR_DATA" ];
then
echo "$YOUR_DATA" > ${BUILT_PRODUCTS_DIR}/${PRODUCT_NAME}.app/your_file.json;
fi
Not sure if I'm getting your specifications right here but this is what I have implemented as well as some help from this solution: How can I save a JSON response to a file that would be accessible from within a local HTML file loaded inside UIWebWiew
(1) Here is the function that will grab the json file. This function is basically assigning
the url you are targeting to a string. Then formatting it to a NSURL. This is then
formatted as NSData which will grab the contents of the url. The data will be serialised and
then ready to target the appropriate elements.
- (void)fetchJson
{
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *urlString = #"localhost:3000/example";
NSURL *url = [NSURL URLWithString:urlString];
NSData *jsonData = [NSData dataWithContentsOfURL:url];
NSError *error = nil;
if(jsonData != nil)
{
NSError *error = nil;
id result = [NSJSONSerialization JSONObjectWithData:jsonData options:NSJSONReadingMutableContainers error:&error];
if (error == nil)
NSLog(#"%#", result);
// (2) This part is dependent on how your json data is arranged (Target the
// right elements).
_endpoint = [result objectForKey:#"endpoint"];
if(_endpoint == null){
NSLog(#"%#", result);
}
else{
//(3) This will save your data into the specified file name under the application documents directory.
NSString *filePath = [NSString stringWithFormat:#"%#/%#", documentsDirectory,#"example.json"];
[result writeToFile:filePath atomically:YES];
}
}
else {
NSLog(#"%#", error);
}
}
(4) To refer to the file in the application documents directory
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSError *jsonError = nil;
NSString *jsonFilePath = [NSString stringWithFormat:#"%#/%#", documentsDirectory,#"data.json"];
NSData *jsonData = [NSData dataWithContentsOfFile:jsonFilePath options:kNilOptions error:&jsonError ];
Right now I have an app that successfully parses JSON from my website. So whenever there is no internet connection, my app crashes. Now I am trying to make it so that when the app is loaded with no internet connection, it will show the data that was shown previously. What would be the best way to do this?
I read this article but I don't know how to embed a JSON file into my app bundle. Could someone explain how to do this?
Thanks in advance!
The best way is:
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *path = [documentsDirectory stringByAppendingPathComponent:#"YourParsedJSON.plist"];
NSFileManager *fileManager = [NSFileManager defaultManager];
if (noInternet){
if ([fileManager fileExistsAtPath: path]){
// if this is true, you have a saved version of your JSON
YourArray = [[NSMutableArray alloc] initWithContentsOfFile: path];
// or
YourDict = [[NSMutableArray alloc] initWithContentsOfFile: path];
}
else{
// first time the app is running, and no internet, no json, inform user about this
}
}
else{
// make an array or dictionary ( what is your JSON )
// response can be a NSDictionary or NSArray
// YourArray = parsedJSON or YourDict = parsedJSON
[YourArray writeToFile:path atomically:YES];
//or
[YourDictionary writeToFile:path atomically:YES];
}
I hope it helps !
Use Apple Reachability sample code to check if your app is able to establish connection to your server.
On first successful request-response, parse the JSON and cache it to disk as a .plist file. This will save you parsing the stored response again. A parsed JSON response can be a NSDictionary or NSArray. Use the writeToFile:atomically: API to write it to disk.
On subsequent request, if reachability fails, i.e. no network connectivity, read the cached response from disk. You need to decide the cache duration and update the plist when a fresh response is fetched.
Hope that helps!
EDIT:
I think I did not understand the question completely. Thanks Xman, for pointing it out. What I would have done in this case is - save the last loaded JSON file to my bundle and use it for displaying information while querying the server and loading updates in the background.
The flow should be like this:
Parse and display data using local JSON file. (Assuming there is local copy of JSON file)
Query the server for latest data.
Upon receiving response, update the bundle with the latest JSON file.
Then, do step 1. In case there is no JSON file, just start from step 2. If there is a Network error display the appropriate information.
This SO question answers how to handle Network connections in iOS: How to check for an active Internet connection on iOS or OSX?
Saving file locally:
Assuming you have the unparsed JSON data in a NSString (responseString) do the following:
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *filePath = [NSString stringWithFormat:#"%#/%#", documentsDirectory, #"latest_json.json"];
NSError *error;
[jsonString_ writeToFile:filePath atomically:YES encoding:NSUTF8StringEncoding error:&error];
NSLog(#"%#", error)
Reading file
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *filePath = [NSString stringWithFormat:#"%#/%#", documentsDirectory, #"latest_json.json"];
NSString *jsonString_ = [NSString stringWithContentsOfFile:filePath encoding:NSUTF8StringEncoding error:&error];
Previous Answer
Embedding JSON file is similar to embedding any resource into your project. The following method shows you how I added an XML file and accessed it in my app.
Drag and drop your JSON/XML file to your resources group/folder in your XCode window. If you don't have the Resouces folder, it is better you create it. Then in your code do this:
NSString* filePath_ = [[NSBundle mainBundle] pathForResource:#"fileName" ofType:#"json"];
NSString *jsonString = [[NSString alloc] initWithContentsOfFile:filePath encoding:NSUTF8StringEncoding error: NULL];
the variable jsonstring contails the JSON information. It is upto you how you would like to parse it.