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You may have heard of JSON before.

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No, I'm not talking about my name.

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I'm talking about
the serialization format.

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JSON stands for
JavaScript Object Notation and

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is a way of serializing data so
that you can access it later.

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Why are we talking about this
in Ruby when it's JavaScript?

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I'm so glad you asked.

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JSON is a plain text serialization format,

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which means you don't really need any
special software to read or write it.

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You only need to be prepared for the
different formats of objects inside it.

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JSON may have started with JavaScript,
but it's in wide use now.

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And it's pretty much standard that
every programming language can read or

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write JSON.

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Let's take a look at reading, writing, and
working with JSON now using Workspaces.

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>> Okay, so let's go ahead and take a look
at how we can use JSON in our Ruby code.

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So first,
here is the JSON documentation and

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you can find that in notes
right below the video.

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Now, what we need to do is require it, and

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then we can send in a string
to the parse method.

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And that should return an object for us.

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So, let's go ahead and see how that works.

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I'm gonna load up IRB.

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And first, I need to require JSON.

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I'm gonna create a string, here.

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And we'll say that this string has a key

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with the name Jason, and
location of Treehouse,

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and the year, which is 2015.

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Okay, so we've got our case and
json_string.

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Now, if we wanted to turn that into a Ruby
object, we could use that parse method.

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So we could say JSON.parse,
and then send in the string.

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And we get back a Ruby object
with everything correctly parsed.

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It's got these hash keys for
name, location, and year.

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And we could assign this to
a variable if we wanted to.

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And this goes from string to a hash.

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Similarly, if we had another hash.

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Let's say my_hash is name Jason.

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Now this is a Ruby hash,
email jason@teamtreehouse.com.

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And we'll say favorite numbers the array

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with the numbers 1, 2, and 3.

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So we've got this hash and
if we want to turn that into

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a JSON object,
we can use JSON.dump(my_hash).

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And now we get back a JSON string
representation of our hash.

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And this could be converted back as well.

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So we could say,
json_output = JSON.dump(my_hash).

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Now we know that this is a string.

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By asking it what class it is,
okay, we know it's a string.

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Now we could parse this just
like other JSON, JSON.parse.

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That output,
would help if I spelled it correctly.

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And we get back a Ruby
hash based on that string.

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And it even has an array
as one of the members.

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There's one other useful method with JSON,
that we can use.

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And that is the load method.

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We can load JSON from a source,
which could either be a string or a file.

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So I've prepared
an example JSON file here.

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That just has that original JSON string
in a file, and we can do JSON.load.

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Now, remember we have to give this
a file so we'll just say file.new.

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And the path which is example.json.

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And this returns our Ruby hash.

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Now one thing to keep in mind
when you are parsing JSON.

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This is going directly into Ruby.

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So, if you're going to use the load
method, make sure that the data is trusted

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and clean, or
there could be security concerns.

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Try working with JSON or
your own now, using Workspaces.