How to process response from Instapaper API? - ios

I make a request to the Instapaper API, and it's supposed to return JSON. It returns something close to JSON, but not completely, like follows:
2013-05-30 19:54:20.155 --[53078:c07] (
{
type = meta;
},
{
"subscription_is_active" = 1;
type = user;
"user_id" = --;
username = "--#gmail.com";
},
{
"bookmark_id" = 387838931;
description = "";
hash = YHwQuwhW;
"private_source" = "";
progress = 0;
"progress_timestamp" = 0;
starred = 0;
time = 1369954406;
title = "Adobe Finally Releases Kuler Color-Picking App for iPhone - Mac Rumors";
type = bookmark;
url = "http://www.macrumors.com/2013/05/30/adobe-finally-releases-kuler-color-picking-app-for-iphone/";
},
How do I then process this? Can I take it and turn it into an NSDictionary even though it doesn't seem to be valid JSON?

From Instapaper API Docs:
Instapaper strings are always encoded in UTF-8, and Instapaper expects all input to be in UTF-8.
Unless otherwise noted, output from every method is an array. The output array is returned as JSON by default.
You can specify a jsonp parameter with a callback function name, e.g. jsonp=myCallback, to use JSONP and wrap the output in a call to the specified function.
So there is no way you will get not valid JSON!
Try following code:
NSData *jsonData = [[NSString stringWithContentsOfURL:[NSURL urlWithString:#"http://your-instapeper-API-link"] encoding:NSUTF8StringEncoding error:nil] dataUsingEncoding:NSUTF8StringEncoding];
NSError *error;
id serializationJSON = [NSJSONSerialization JSONObjectWithData:jsonData options:NSJSONReadingMutableContainers error:&error];
And then you can log what is wrong or if result is what you expect:
NSLog(#"class of JSON input: %# \n and possible error: %#",[serializationJSON class],error);
Of course you should expect Array and no error.
EDIT ... based on coment code:
Based on docs you should get Array or Dictionary. Please add this core instead your line #23 (numer from here):
if([JSON isKindOfClass:[NSDictionary class]]) {
NSDictionary *jsonDictionary = JSON;
NSLog(#"%#",[jsonDictionary allKeys]);
} else {
NSLog(#"JSON object class: %#",[JSON class]);
}
and please show us output.
One more thing:
You get array from request. Great! This is a valid JSON. So you need to debug it. As i said it's a shame is not a unlimited acccess public API, so i can look into it. But now you have to debug your result. I see in your code that you are trying to access bookmarks. So i look into Bookmarks section in docs and this is some kind of list (NSArray). So if you don't know what result you want. You should print them into log (or set a breakpoint). Replace code from my earlier update with this simple log:
NSDictionary *resultDictionary;
if([JSON isKindOfClass:[NSArray class]]) {
NSArray *jsonArray = JSON;
NSLog(#"so json is an array with %i objects",[jsonArray count]);
for(id objectInsideArr in jsonArray) {
NSLog(#"object in array [class]: %# [value]: %#",[objectInsideArr class],objectInsideArr); //if here you find NSDictionary maybe is this dictionary you are looking for. I'm not sure what it is.
if([objectInsideArr isKindOfClass:[NSDictionary class]]) {
resultDictionary = [[NSDictionary alloc] initWithDictionary:objectInsideArr];
}
}
}

If it were me I would write a custom formatter to get it into JSON format and then use NSJSONSerialization once I know it is valid. What you posted is so far from valid there is no way it would work. I'm surprised they are returning it in that format, do they provide some kind of library for consuming their services?

If you want something even simpler, I can give you my CGIJSONObject library that will handle JSON using reflection - you just need to mirror the keys in APIs with your classes andit is good to go.

Related

iOS JSON Parsing, Format Issues

So I was working on a project that required me to work with some JSON, I was running into a few issues regarding the best way of representing things. First of, this is how the JSON looks:
"phoneList": [
{
"phoneReason": "End of Contract",
"phoneType": [
{
"id": 5,
"phoneType": "Android Smartphone"
}
]
}
]
I want to know the most appropriate way of representing this.
For example, I do know that that my phoneReason will just be a simple NSString while my phoneType is actually a NSArray. However,I wasn't sure how to represent a)the id, I know this is an integer, but should this be an NSInteger or an NSNumber and b)could someone point me in the direction of some sample code where I can understand how to model a dictionary object containing an integer and a string and also where I can understand how to model an array of dictionaries.
My other question is also similar in that say I'm actually posting something, how do I model this, specifically say for like dictionary type (JSON Curly Brace)objects that contain a number/integer and a string.
For example, this is the JSON I'm trying to model and then do something like this:
"phoneReason": "Upgrade",
"phoneInfo": {
"id": "2"
},
//And then I want to pass ID
-(void) createOurRequest:(NSNumber *)id {
NSDictionary *myDictionary = #{
#"phoneReason" : [NSString stringWithFormat:#"%i", s elf.dat.reason],
//How do I then represent the phoneInfo element exactly?
};
Sorry, for the clumsy question, would really appreciate any guidance on modeling JSON in iOS or just generally.
I'm assuming you're asking questions a) and b), and also how to model a JSON.
a) The unfortunate thing with Obj-C is that all collection elements have to be objects. Integers are value types, so they will need to be converted to NSNumbers to work. However, if you're parsing a JSON string, the builtin JSON parser does it for you. I'll describe it below.
b) The model is based on the JSON. You describe the object collection and the parser will determine the model for you. In your example, you would have a NSDictionary<NSString *: NSArray<NSDictionary<NSString *: id>*>*>. The innermost element has value of id because you can either have an NSString ("End of Contract") or an NSArray ("phoneType": [ { "id": 5, "phoneType": "Android Smartphone" } ])
Of course, the model is defined by your JSON, so if you run it through a parser, you get a structured object. You can access each element based on your model (object[#"phoneList"][#"phoneReason"]).
The class method to use is:
+ (id)JSONObjectWithData:(NSData *)data
options:(NSJSONReadingOptions)opt
error:(NSError **)error
Where you pass it a NSData representation of your string, options (or 0), and a NSError pointer (error*). You get back a parsed JSON with the proper structure you defined.
NSDictionary *parsedJSONObject = [NSJSONSerialization JSONObjectWithData:jsonData options:0 error:NULL
I have no options to use and I know there will be no error, so I pass nothing for those parameters. The resulting object will be in whatever structure your JSON is.
Using the objects and the json layout you provided in your first example, this is how I would go about creating the dictionaries and arrays to get the json in the format you specified. Hopefully this helps make it a little clearer for you.
// example constructor method
-(void) jsonStringWithPhoneReason:(NSString*)reason phoneId:(NSInteger)phoneId phoneType:(NSString*)phoneType
{
// create device detail dictionary
NSDictionary *deviceOneDetail = #{
#"id" : #(phoneId), // <- set phone id as NSNumber
#"phoneType" : phoneType // <- set your string phone type
};
// create device dictionary
NSDictionary *deviceOne = #{
#"phoneReason" : reason, // <- set your phone reason string
#"phoneType" : #[deviceOneDetail] // <- set your phone type dictionary within an array
};
// create phone list dictionary with any device dictionaries you want to add
NSDictionary *phoneListDict = #{
#"phoneList" : #[
deviceOne, // <- add your device to the phone list array of dictionaries
// deviceTwo...
]
};
NSString *jsonString = [self convertToJsonString:phoneListDict]; // <- convert the dictionary into a json string and use however you wish
// your json string should now look like this assuming you pass 'End of Contract', 5 & 'Android Smartphone' as arguments to this method
// {"phoneList":[{"phoneReason":"End of Contract","phoneType":[{"id":5,"phoneType":"Android Smartphone"}]}]}
}
-(NSString*) convertToJsonString:(NSDictionary*)dictionary
{
NSError *error;
NSData *jsonData = [NSJSONSerialization dataWithJSONObject:dictionary
options:0 // Pass 0 if you don't care about the readability of the generated string
error:&error];
if (error)
{
NSString *errorDesc = [NSString stringWithFormat:#"Error creating json data from dictionary: %#", error.localizedDescription];
NSLog(#"ERROR: %#", errorDesc);
jsonData = nil;
return nil;
}
NSString *returnString = nil;
if(jsonData != nil)
{
returnString = [[NSString alloc] initWithData:jsonData encoding:NSUTF8StringEncoding];
}
return returnString;
}

Getting data from API, need to filter results

I'm working with data from a Foursquare API.
I want to get a list of coffee shops, and am getting that back correctly (I'm using RestKit)... but once I get that list, on my end I need to filter out any coffee shop that is a "Starbucks".
So right now I only know how to pull in all coffee shops, but I don't know how to parse that data once I have it before I serve it into the app table view so that there will be no Starbucks coffee shops listed.
Any ideas how I could do that? Let me know if you need any of my code snippets posted that might help. Thanks!
EDIT
Normal response type from the API would be:
"venue": [{
"name": "ABC Coffee Shop", {
So I would need to take "name" and filter out any name that was "Starbucks".
If FourSquare doesn't let you apply a filter to the request, to filter on the name "Starbucks" then what I would do with this is the following.
I would start by deserializing the response into a JSON Object, which in this case will be a dictionary.
NSError *error = nil;
NSDictionary *responseDict = [[NSJSONSerialization JSONObjectWithData:foursquareResponse options:0 error: &error];
NSArray *starbucks = nil;
if (!error) {
NSArray *coffeeShops = responseDict[#"venue"];
starbucks = [coffeeShops filteredArrayUsingPredicate:[NSPredicate predicateWithFormat:#"name = 'Starbucks'"]];
} else {
// handle the error
}
NSLog(#"Starbucks: %#", starbucks");
I didn't test this code but I think it should get you on your way.
Looks like JSON to me, you could just use the built in JSON parser, the NSJSONSerialization class. Here is a method I built that takes an NSData JSON parameter, deserializes it and returns a dictionary.
- (NSMutableDictionary *)deserialize: (NSData *)data {
return [[NSJSONSerialization JSONObjectWithData:data options:kNilOptions error: nil] mutableCopy];
}
I don't know the structure of Foursquare's response inside out, so you might want to NSLog() the returned dictionary to see how you can now reference to it.

Parse double quotes and single quotes in Json Parsing

I am parsing a JSON url. I am getting \u00e2\u20ac\u0153 instead of single quotes and \u00e2\u20ac\u009d instead of double quotes. On my end i am doing NSUTF8StringEncoding but still not getting single and double quotes.
Here is the response in the web browser:
{"status":"1","data":[{"id":"1345","title_en":"","content_en":"Mom
said, \u00e2\u20ac\u0153I love this one.\u00e2\u20ac\u009d\n\nJake
said, \u00e2\u20ac\u0153I don\u00e2\u20ac\u2122t get
it.\u00e2\u20ac\u009d\n","image":"1396","pos":"2","video_type":"0","video":"0","video_alt":"","sound_type":"1","sound":"1123","sound_alt":"","author":"","type":"0","book_id":"148","user_id":"24","title":"The
Art
Museum","author_url":"maureen-d-1","book_url":"the-art-museum","video_filename":"","sound_filename":"atmuseum2.m4a"}]}
Is it possible to parse above response using NSUTF8StringEncoding or something else. Or i need to get it done from php side.
Do you use NSJSONSerialization? In my app i do this:
NSError* localError;
id jsonObjects = [NSJSONSerialization JSONObjectWithData:data
options:NSJSONReadingMutableContainers
error:&localError];
In "data" variable i have response from server. I receiving UTF-encoded text from server too (like \u00e2\u20ac) but finally i get normal string. "jsonObjects" will contain data in native types:
if ([jsonObjects isKindOfClass:[NSDictionary class]])
{
NSNumber* age = [jsonObjects objectForKey:#"age"];
//...etc
}

JSONKit parsing issue

I am receiving a JSON object like this:
{"data":null,
"error":1,
"error_code":"InvalidSID",
"sid":"",
"num_rows_total":0,
"last_insert_id":0,
"error_info":"Comment...",
"error_data":[]}
and JSONKit using this code:
NSString *responseString = [request responseString];
NSDictionary *requestDictionary = [responseString objectFromJSONString];
if([[requestDictionary objectForKey:#"error"] intValue]) {
if([#"InvalidSID" isEqualToString:[requestDictionary objectForKey:#"error_code"]]) {
[self.navigationController popViewControllerAnimated:YES];
}
}
produces such output:
{
data = "<null>";
error = 1;
"error_code" = InvalidSID;
"error_data" = ();
"error_info" = "Comment...";
"last_insert_id" = 0;
"num_rows_total" = 0;
sid = "";
}
The problem is, that this if statement is never called because of missing quotation marks around InvalidSID. Is there any known problem with JSONKit that makes those quotation marks disappear?
You are confusing the "description" output from NSDictionary with the value of a key. You also could have saved yourself a lot of time (that is the time you posted this to the time you get some response) by using some simple detective work.
I assume that what you call "output" above is the result of
NSLog(#"%#", requestDictionary);
So after that line try this:
// Just to be complete
id ee = [requestDictionary objectForKey:#"error"];
NSLog(#"error=%# intValueOfError=%d classOfErrorCode=%#",
ee, [ee intValue], NSStringFromClass([ee class]) );
// Where I suspect you may discover something
id ec = [requestDictionary objectForKey:#"error_code"];
NSLog(#"errorCode=%# classOfErrorCode=%#",
ec, NSStringFromClass([ec class]) );
We do that since something is obviously wrong here, we want to find out more about the objects we have in hand. I am going to guess if you do the above you will discover something you did not expect.

Parsing JSON response with multiple objects

I've got a question regarding parsing a JSON response within iOS5.
Currently, I'm following this guide here to help me parse the JSON response returned from a third-party mapping service.
Everything works, except that the JSON response returned by the third-party server is somewhat different from the one shown in the guide itself.
In a nutshell, the overall structure of the entire JSON response looks something like this:
{
"directions": [....],
"messages": [....],
"routes":
{
"features": [
{
"attributes": {....},
"geometry":
{
"paths": [....]
}
}
]
}
}
This is the actual JSON query URL.
By using this line of code,
NSDictionary * jsonResponse = [NSJSONSerialization JSONObjectWithData:responseData options:kNilOptions error:&error];
I am able to sucessfully get the jsonResponse dictionary to report that it has 3 key/value pairs, but my ultimate goal is to retrieve the array stored in 'routes.features.geometry.paths'.
This is my current code block that gets the final set of array values:
NSDictionary * jsonResponse = [NSJSONSerialization JSONObjectWithData:responseData options:kNilOptions error:&error];
NSArray * jsonArray = [jsonResponse valueForKeyPath:#"routes.features.geometry.paths"];
jsonArray = [jsonArray objectAtIndex:0];
jsonArray = [jsonArray objectAtIndex:0];
I was wondering if anyone might have a better idea of how I should go about doing this in a more elegant fashion?
Thanks a lot in advance!
You can't just use it as JSON object because it will be working as JSON (Plain String) and you need to parse it so for your problem you can do like this to directly go to paths
NSArray *arr = [[[[jsonResponse objectForKey:#"routes"] objectForKey:#"features"] objectForKey:#"geometry"] objectForKey:#"paths"];
Now you can access your paths data from "arr" array
UPDATE:
NSArray *arr = [[[[[jsonResponse objectForKey:#"routes"] objectForKey:#"features"] objectAtIndex:0] objectForKey:#"geometry"] objectForKey:#"paths"];
as features element is an Array so traverse array first then goto its elements

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