jwhitehorn

var CampgroundPhoto = db.define("campground_photos", {
  photo_url: String,
  campground_id: Number,
  updated_at: Date
}, {
  hooks: {
    beforeSave: function(next){
      this.updated_at = new Date();
      next();
    }

jwhitehorn

app.get('/api/updates/:model', function (req, res) {

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dispatch_async(syncQueue, ^{

jwhitehorn

@interface Sync()

@property (nonatomic) dispatch_queue_t syncQueue;

@end

@implementation Sync

@synthesize syncQueue;

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dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{

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- (IBAction)doApplyUpdate:(id)sender {
    [[Sync defaultWorker] applyOutstandingUpdates];
}

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#import "Sync.h"
#import "NSData+MD5Digest.h"

@implementation Sync

+ (Sync *) defaultWorker {
    //GCD singleton pattern: http://www.galloway.me.uk/tutorials/singleton-classes/
    static Sync *defaultWorker = nil;
    static dispatch_once_t onceToken;
    dispatch_once(&onceToken, ^{

jwhitehorn

NSArray *documentPaths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectoryPath = [documentPaths objectAtIndex:0];

NSString *checksum = nil;
BOOL initialSync = YES;
if([this isUpdatePending]){
    NSString *filePath = [documentsDirectoryPath stringByAppendingPathComponent:@"updated.db"];
    NSData *contents = [NSData dataWithContentsOfFile:filePath];
    checksum = [contents MD5HexDigest];
    initialSync = NO;

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- (void) applyOutstandingUpdates {
    __weak id this = self;
    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
        if(![this isUpdatePending]){
            return; //no update pending
        }
        
        NSArray *documentPaths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
        NSString *documentsDirectoryPath = [documentPaths objectAtIndex:0];
        

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- (BOOL) isUpdatePending {
    NSArray *documentPaths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    NSString *documentsDirectoryPath = [documentPaths objectAtIndex:0];
    
    NSString *filePath = [documentsDirectoryPath stringByAppendingPathComponent:@"updated.db"];
    
    NSFileManager *fileManager = [NSFileManager defaultManager];
    return [fileManager fileExistsAtPath:filePath];
}