{"id":11650,"date":"2016-03-28T12:11:41","date_gmt":"2016-03-28T09:11:41","guid":{"rendered":"https:\/\/www.webcodegeeks.com\/?p=11650"},"modified":"2016-03-18T20:42:17","modified_gmt":"2016-03-18T18:42:17","slug":"json-ld-building-meaningful-data-apis","status":"publish","type":"post","link":"https:\/\/www.webcodegeeks.com\/javascript\/json-ld-building-meaningful-data-apis\/","title":{"rendered":"JSON-LD: Building Meaningful Data APIs"},"content":{"rendered":"

Everybody loves JSON<\/a>!<\/p>\n

However, JSON by itself is pretty meaningless. Well. It has meaning, but only to the original creator of that format. They can share that meaning via documentation, conversation, or usage, but those often exist in places far removed from the JSON document you\u2019re looking at.<\/p>\n

What if the meaning itself was encoded directly into the document? What if every key in a JSON document had its own unique identity which you could look up (because web!) and read about its meaning? Wouldn\u2019t that be slick?<\/p>\n

Well. It\u2019s quite possible, actually.<\/p>\n

Here\u2019s what I mean. Below is a pretty typical bit of \u201cperson\u201d information written in JSON with English key names (to match this article\u2019s content):<\/p>\n

{\r\n  \"first_name\": \"Benjamin\",\r\n  \"last_name\": \"Young\",\r\n  \"alias\": \"BigBlueHat\",\r\n  \"email\": \"byoung@bigbluehat.com\"\r\n}<\/pre>\n
You likely know what all that means (more or less). However, your software doesn\u2019t, unless you coded it exactly to those string names. While there\u2019s some possibility we picked the same keys (yay us!), there\u2019s a higher likelihood we didn\u2019t. We probably fix our :coffee:<\/code> differently too. Who knows.<\/p>\n
Currently, we\u2019d need to write some code that took my JSON and turned the first_name<\/code> key into your firstName<\/code> key (or into first<\/code> which is inside your name<\/code> object or into given<\/code> or\u2026 whatever). We\u2019d then need to do that again the next time we found someone else with information about a person that used different key names. Rinse. Repeat.<\/p>\n
What if we could match first_name<\/code>, name.first<\/code>, given<\/code>, and even an obfuscated sadfeqpoif<\/code> key into a meaningful Thing<\/em> which made each of these \u201cmean\u201d the same thing? It can be done!<\/p>\n
\"json-ld-button\"<\/a><\/p>\n
Meet JSON-LD<\/a>! JSON-LD stands for \u201cJSON for Linked Data.\u201d It\u2019s a specification for encoding contextualized meaning into otherwise meaningless JSON documents.<\/p>\n
Here\u2019s an example:<\/p>\n
{\r\n  \"@context\": {\r\n    \"@vocab\": \"http:\/\/schema.org\/\",\r\n    \"first_name\": \"givenName\",\r\n    \"last_name\": \"familyName\",\r\n    \"alias\": \"alternateName\",\r\n    \"email\": \"email\"\r\n  },\r\n  \"first_name\": \"Benjamin\",\r\n  \"last_name\": \"Young\",\r\n  \"alias\": \"BigBlueHat\",\r\n  \"email\": \"byoung@bigbluehat.com\"\r\n}<\/pre>\n
In this upgraded<\/em> version of the earlier JSON document, you\u2019ll see a new @context<\/code> object. This object handles the mapping from my ad hoc terminology to the Schema.org<\/a> vocabulary which is referenced via value of @vocab<\/code>.<\/p>\n
The key\/value pairs below the @vocab<\/code> key map directly to meaningful URLs at http:\/\/schema.org\/<\/code>. Now, my keys have meaning. Each key now has:<\/p>\n