APSmartStorage: An Objective-C repository from Alty

APSmartStorage helps to get data from network and automatically caches data on disk or in memory in a smart configurable way. Here is how the APSmartStorage flow diagram looks like:

Features

Load cached object from memory by URL
Load cached object from file by URL
Load object from network by URL
Store loaded object to file
Store loaded object to memory
Parse loaded data from network (for instance, NSData to UIImage)
Track loading progress
Automatically purge memory cache on memory warning
Set max object count to keep in memory to prevent memory overflow
Set custom NSURLSessionConfiguration

Installation

Add APSmartStorage pod to Podfile

Using

Load object

Here is example how to use APSmartStorage to store images

// setup data parsing block
APSmartStorage.sharedInstance.parsingBlock = ^(NSData *data, NSURL *url)
{
    return [UIImage imageWithData:data scale:UIScreen.mainScreen.scale];
};
...
// show some progress/activity
...
// load object with URL
[APSmartStorage.sharedInstance loadObjectWithURL:imageURL completion:^(id object, NSError *error)
{
    // hide progress/activity
    if (error)
    {
        // show error
    }
    else
    {
        // do something with object
    }
}];

Very often you don't need to store downloaded object in memory. For instance, you perform some background download for future, and you don't want to keep this objects in memory right now.

[APSmartStorage.sharedInstance loadObjectWithURL:someURL storeInMemory:NO completion:^(id object, NSError *error)
{
    // do something
}];

But if any method call sets storeInMemory:YES object will be stored in memory

Track load progress

[APSmartStorage.sharedInstance loadObjectWithURL:someURL storeInMemory:NO progress:^(NSUInteger percents)
{
    // show progress percents value is between 0 and 100
}                                     completion:^(id object, NSError *error)
{
    // do something
}];

Update stored object

Objects stored at files could become outdated after some time, and application should reload it from network

[APSmartStorage.sharedInstance reloadObjectWithURL:objectURL completion:(id object, NSError *error)
{
    if (error)
    {
        // show error and do something like use outdated version of object
    }
    else
    {
        // do something with object
    }
}];

Remove objects from memory

// remove object from memory
[APSmartStorage.sharedInstance removeObjectWithURLFromMemory:objectURL];
// remove all objects form memory
[APSmartStorage.sharedInstance removeAllFromMemory];

Remove object from memory and delete file storage

// remove object from memory and remove it file
[APSmartStorage.sharedInstance removeObjectWithURLFromStorage:objectURL];
// remove all objects from memory and all storage files
[APSmartStorage.sharedInstance removeAllFromStorage];

This methods also cancel network requests. And if request has been cancelled, callbacks will run with nil as object and with error with code 701.

Parse network and file data

If parsingBlock doesn't set you will receive raw NSData downloaded from network or read from file. So you should set one in most cases. If you need to parse data of different formats it will be a bit more complicated:

APSmartStorage.sharedInstance.parsingBlock = ^(NSData *data, NSURL *url)
{
    // is URL of image
    if ([url isImageURL])
    {
        return [UIImage imageWithData:data scale:UIScreen.mainScreen.scale];
    }
    // this is URL of something else
    else
    {
        return [SomeObject objectWithData:data];
    }
};

Set max objects count to keep in memory

If max object count reached random object will be removed from memory before add next one

APSmartStorage.sharedInstance.maxObjectCount = 10;

Setup custom `NSURLSessionConfiguration`

APSmartStorage.sharedInstance.sessionConfiguration = sessionConfiguration;

History

Releases

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Alterplay/APSmartStorage