Using Cypher (Neo4j) within a REST API request (Objective C)

Question

I am trying to query my Neo4j database, using the REST API.

I have this working so far without using the Cypher query language to retrieve data, however, now I need to get nodes which are sorted by 'newest' i.e. unix timestamp DESC.

I have tried to add the query within the HTTP body of the NSMutableURLRequest but I am just getting the HTTP error 405.

Here is my code:

NSURL *url = [NSURL URLWithString:[NSString stringWithFormat:@"%@node/%i", EventsManagerDataURL, creatorID]];

NSLog(@"Connecting to URL: %@", url);

NSMutableURLRequest *request = [[NSMutableURLRequest alloc] initWithURL:url];

NSString *jsonMap = @"{'query' : 'start x  = node(4,6,7) return x order by x.datestart,'params' : {}}";
NSData *jsonData = [jsonMap dataUsingEncoding:NSUTF8StringEncoding];

[request setHTTPMethod:@"POST"];

[request setValue:@"application/json" forHTTPHeaderField:@"Accept"];
[request setValue:@"application/json" forHTTPHeaderField:@"Content-Type"];
[request setValue:[NSString stringWithFormat:@"%d", jsonData.length] forHTTPHeaderField:@"Content-Length"];

[request setHTTPBody:jsonData];

[NSURLConnection sendAsynchronousRequest:request queue:[[NSOperationQueue alloc] init] completionHandler:^(NSURLResponse *response, NSData *data, NSError *error){

    if (data){
        NSLog(@"%s. Data: %@", _cmd, [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding]);
    } else {
        NSLog(@"Error: %@", error.localizedDescription);
    }
}];

Eve Freeman · Accepted Answer · 2013-01-23T17:14:03.727

3

You're missing a single quote here:

NSString *jsonMap = @"{'query' : 'start x  = node(4,6,7) return x order by x.datestart***'***,'params' : {}}";

And actually, it needs to have double quotes:

NSString *jsonMap = @"{\"query\" : \"start x  = node(4,6,7) return x order by x.datestart\", \"params\" : {}}";

Test with cURL:

curl -H Accept:application/json -H Content-Type:application/json -X POST -d '{"query" : "start x  = node(4,6,7) return x order by x.datestart", "params" : {}}' localhost:7474/db/data/cypher

edited Jan 23 '13 at 17:14

answered Jan 23 '13 at 17:08

Eve Freeman

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Thanks for your reply, the cURL seems to work, however, I still get the 405 error in my `NSLog` :/ – Adam Carter Jan 23 '13 at 17:26
Make sure your URL is right, too. I've had issues with that before. – Eve Freeman Jan 23 '13 at 17:30
Yeah, the URL was pointing to a node, not the `cypher` path. Thanks! – Adam Carter Jan 23 '13 at 17:37
1

I'm trying to get my coworker to write an Objective-C REST wrapper for Cypher. Hopefully that will make some of this syntax prettier. :) – Eve Freeman Jan 23 '13 at 17:41
Yeah! I've made/making a basic Objective-C class, which I am using, but one made by someone with a lot more experience than me would be great! Please link me to it if you ever convince him! – Adam Carter Jan 23 '13 at 17:55
Thank you for the help with the curl example. In my case I was missing the POST part. – Sridhar Sarnobat Sep 02 '13 at 02:33

Using Cypher (Neo4j) within a REST API request (Objective C)

1 Answers1