PHP - 将新的JSON数据附加到现有的多维JSON

Question

I have a JSON file like this

[
  {
    "channel": "RSS Channel",
    "description": "RSS Description",
    "publish_date": "Wed, 17 Feb 2016 16:21:30 +0000",
    "last_build_date": "Wed, 17 Feb 2016 16:21:30 +0000",
    "generator": "A Human",
    "link": "mysite.com",
    "atom_link": "http://example.com/index.rss",
    "feed": [
      {
        "post_id": "3",
        "title": "Some RSS feed 3...",
        "publish_date": "Wed, 17 Feb 2016 16:30:55 +0000",
        "link": "http://example.com/#post3",
        "guid": "http://example.com/#post3",
        "author": "WhoAmI?",
        "content": "More!"
      },
      {
        "post_id": "2",
        "title": "Some RSS feed 2...",
        "publish_date": "Wed, 17 Feb 2016 16:30:55 +0000",
        "link": "http://example.com/#post3",
        "guid": "http://example.com/#post3",
        "author": "WhoAmI?",
        "content": "More!"
      },
      {
        "post_id": "1",
        "title": "Some RSS feed 1...",
        "publish_date": "Wed, 17 Feb 2016 16:30:55 +0000",
        "link": "http://example.com/#post3",
        "guid": "http://example.com/#post3",
        "author": "WhoAmI?",
        "content": "More!"
      }
    ]
  }
]

I want PHP to be able to append another post to the feed section but I'm not sure how. Here is what I have by far:

$data = json_decode($json, true);

$channel_no = 0;
$channel_name = $data[$channel_no]['channel'];
$channel_description = $data[$channel_no]['description'];
$channel_lastbuilddate = $data[$channel_no]['last_build_date'];
$channel_publishdate = $data[$channel_no]['publish_date'];
$channel_generator = $data[$channel_no]['generator'];
$channel_link = $data[$channel_no]['link'];
$channel_atomlink = $data[$channel_no]['atom_link'];
$channel_feed = $data[$channel_no]['feed'];
$channel_feedlen = count($data[$channel_no]['feed']);

// ############ Get the post feed and generate a new one with the new content first ############
$post_title = "Post test";
$post_content = "Yay, it worked! :D";
$post_id = $channel_feedlen + 1;
$post_link = $domain . "/#" . $post_id;
$post_guid = $domain . "/#" . $post_id;
$post_author = "Someone";


$new_postArray = array('post_id' => $post_id, 'title' => $post_title, 'publish_date' => $today, 'link' => $post_link, 'guid' => $post_guid, 'author' => $post_author, 'content' => $post_content); // Array of new post content.

for($x = 0; $x < $channel_feedlen; $x++) { // Read through existing posts that are currently in the .JSON
  $feed_id = $channel_feed[$x]['post_id'];
  $feed_title = $channel_feed[$x]['title'];
  $feed_publishdate = $channel_feed[$x]['publish_date'];
  $feed_link = $channel_feed[$x]['link'];
  $feed_guid = $channel_feed[$x]['guid'];
  $feed_author = $channel_feed[$x]['author'];
  $feed_content = $channel_feed[$x]['content'];

  $post_array = array('post_id' => $feed_id, 'title' => $feed_title, 'publish_date' => $feed_publishdate, 'link' => $feed_link, 'guid' => $feed_guid, 'author' => $feed_author, 'content' => $feed_content);


}

$feed = json_encode($post_array);

$new_json = array('channel' => $channel_name, 'description' => $channel_description, 'last_build_date' => $channel_lastbuilddate, 'publish_date' => $channel_publishdate, 'generator' => $channel_generator, 'link' => $channel_link, 'atom_link' => $channel_atomlink, 'feed' => array($feed));
$encoded_json = json_encode($new_json, JSON_PRETTY_PRINT);
exit($encoded_json);

The aim of this code is to be able to make new posts and append the content to the top of the existing data of the feed tag, then write a new JSON file.

I've looked around for examples ( How to create an array for JSON using PHP? ) of arrays inside of an array in PHP but non of which I was able to get working as I'm not sure how to implement them in my "for" loop.

I want the new JSON output to look like this: https://gist.github.com/lavanoid/4bee9531f7bc6e3165f9

Any help would be appreciated! :D

Answer 1

This should help you out. If you have more than one channel you'll need the index of the channel so you can add the new post to it's feed.

$json = '[
  {
    "channel": "RSS Channel",
    "description": "RSS Description",
    "publish_date": "Wed, 17 Feb 2016 16:21:30 +0000",
    "last_build_date": "Wed, 17 Feb 2016 16:21:30 +0000",
    "generator": "A Human",
    "link": "mysite.com",
    "atom_link": "http://example.com/index.rss",
    "feed": [
      {
        "post_id": "3",
        "title": "Some RSS feed 3...",
        "publish_date": "Wed, 17 Feb 2016 16:30:55 +0000",
        "link": "http://example.com/#post3",
        "guid": "http://example.com/#post3",
        "author": "WhoAmI?",
        "content": "More!"
      },
      {
        "post_id": "2",
        "title": "Some RSS feed 2...",
        "publish_date": "Wed, 17 Feb 2016 16:30:55 +0000",
        "link": "http://example.com/#post3",
        "guid": "http://example.com/#post3",
        "author": "WhoAmI?",
        "content": "More!"
      },
      {
        "post_id": "1",
        "title": "Some RSS feed 1...",
        "publish_date": "Wed, 17 Feb 2016 16:30:55 +0000",
        "link": "http://example.com/#post3",
        "guid": "http://example.com/#post3",
        "author": "WhoAmI?",
        "content": "More!"
      }
    ]
  }
]';

$data = json_decode($json); // converts json to php array of channel objects

$post_title = "Post test";
$post_content = "Yay, it worked! :D";
$post_id = count($data[0]->feed) + 1;
$post_link = $domain . "/#" . $post_id;
$post_guid = $domain . "/#" . $post_id;
$post_author = "Someone";

$new_postArray = array('post_id' => $post_id, 'title' => $post_title, 'publish_date' => $today, 'link' => $post_link, 'guid' => $post_guid, 'author' => $post_author, 'content' => $post_content); // Array of new post content.

// Add new post to BEGINNING of feed
$data[0]->feed = $new_postArray + $data[0]->feed;

$encoded_json = json_encode($data, JSON_PRETTY_PRINT);
exit($encoded_json);
?>