stuartlynn/index.html

## index.html
<html>
  <head>
    <title>S3 POST Form</title>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
  </head>

  <body>
    <form action="https://zooniverse-data.s3.amazonaws.com/" method="post" enctype="multipart/form-data">
      <input type="hidden" name="key" value="cruk_upload/${filename}">
      <input type="hidden" name="AWSAccessKeyId" value={AWSAccessKeyId}>
      <input type="hidden" name="acl" value="private">
      <input type="hidden" name="success_action_redirect" value="http://zooniverse-data.s3.amazonaws.com/cruk_upload/success.html">
      <input type="hidden" name="policy" value={insert_base64_policy_here}>
      <input type="hidden" name="signature" value={insert_signature_here>
      <!-- Include any additional input fields here -->

      File to upload to S3:
      <input name="file" type="file">
      <br>
      <input type="submit" value="Upload File to S3">
    </form>
  </body>
</html>

## policy_doc
{"expiration": "2016-01-01T00:00:00Z",
  "conditions": [
    {"bucket": "zooniverse-data"},
    ["starts-with", "$key", "cruk_upload/"],
    {"acl": "private"},
    {"success_action_redirect": "http://zooniverse-data.s3.amazonaws.com/cruk_upload/success.html"}
  ]
}

## process_policy.rb
require 'base64'
require 'openssl'
require 'digest/sha1'

policy = Base64.encode64(IO.read("policy_doc")).gsub("\n","")

signature = Base64.encode64(
    OpenSSL::HMAC.digest(
        OpenSSL::Digest::Digest.new('sha1'),
        ENV["AWS_SECRET_ACCESS_KEY"], policy)
    ).gsub("\n","")

File.open("b64_policy", "w"){ |f| f.puts policy}
File.open("signature", "w"){ |f| f.puts signature}

puts "policy #{policy}"
puts "signature #{signature}"

## success.html
<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="utf-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <title></title>

    <!-- Bootstrap -->
    <link href="//netdna.bootstrapcdn.com/bootstrap/3.1.1/css/bootstrap.min.css" rel="stylesheet">
    <link href="//netdna.bootstrapcdn.com/font-awesome/4.0.3/css/font-awesome.min.css" rel="stylesheet">

    <!-- HTML5 Shim and Respond.js IE8 support of HTML5 elements and media queries -->
    <!-- WARNING: Respond.js doesn't work if you view the page via file:// -->
    <!--[if lt IE 9]>
      <script src="https://oss.maxcdn.com/libs/html5shiv/3.7.0/html5shiv.js"></script>
      <script src="https://oss.maxcdn.com/libs/respond.js/1.4.2/respond.min.js"></script>
    <![endif]-->
  </head>
  <body>

    <h1>That worked thanks</h1>
    <!-- jQuery (necessary for Bootstrap's JavaScript plugins) -->
    <script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.0/jquery.min.js"></script>
    <!-- Include all compiled plugins (below), or include individual files as needed -->
    <script src="//netdna.bootstrapcdn.com/bootstrap/3.1.1/js/bootstrap.min.js"></script>
  </body>
</html>
	<html>
	<head>
	<title>S3 POST Form</title>
	<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
	</head>

	<body>
	<form action="https://zooniverse-data.s3.amazonaws.com/" method="post" enctype="multipart/form-data">
	<input type="hidden" name="key" value="cruk_upload/${filename}">
	<input type="hidden" name="AWSAccessKeyId" value={AWSAccessKeyId}>
	<input type="hidden" name="acl" value="private">
	<input type="hidden" name="success_action_redirect" value="http://zooniverse-data.s3.amazonaws.com/cruk_upload/success.html">
	<input type="hidden" name="policy" value={insert_base64_policy_here}>
	<input type="hidden" name="signature" value={insert_signature_here>
	<!-- Include any additional input fields here -->

	File to upload to S3:
	<input name="file" type="file">
	<br>
	<input type="submit" value="Upload File to S3">
	</form>
	</body>
	</html>
	{"expiration": "2016-01-01T00:00:00Z",
	"conditions": [
	{"bucket": "zooniverse-data"},
	["starts-with", "$key", "cruk_upload/"],
	{"acl": "private"},
	{"success_action_redirect": "http://zooniverse-data.s3.amazonaws.com/cruk_upload/success.html"}
	]
	}
	require 'base64'
	require 'openssl'
	require 'digest/sha1'

	policy = Base64.encode64(IO.read("policy_doc")).gsub("\n","")

	signature = Base64.encode64(
	OpenSSL::HMAC.digest(
	OpenSSL::Digest::Digest.new('sha1'),
	ENV["AWS_SECRET_ACCESS_KEY"], policy)
	).gsub("\n","")

	File.open("b64_policy", "w"){ \|f\| f.puts policy}
	File.open("signature", "w"){ \|f\| f.puts signature}

	puts "policy #{policy}"
	puts "signature #{signature}"
	<!DOCTYPE html>
	<html lang="en">
	<head>
	<meta charset="utf-8">
	<meta http-equiv="X-UA-Compatible" content="IE=edge">
	<meta name="viewport" content="width=device-width, initial-scale=1">
	<title></title>

	<!-- Bootstrap -->
	<link href="//netdna.bootstrapcdn.com/bootstrap/3.1.1/css/bootstrap.min.css" rel="stylesheet">
	<link href="//netdna.bootstrapcdn.com/font-awesome/4.0.3/css/font-awesome.min.css" rel="stylesheet">

	<!-- HTML5 Shim and Respond.js IE8 support of HTML5 elements and media queries -->
	<!-- WARNING: Respond.js doesn't work if you view the page via file:// -->
	<!--[if lt IE 9]>
	<script src="https://oss.maxcdn.com/libs/html5shiv/3.7.0/html5shiv.js"></script>
	<script src="https://oss.maxcdn.com/libs/respond.js/1.4.2/respond.min.js"></script>
	<![endif]-->
	</head>
	<body>

	<h1>That worked thanks</h1>
	<!-- jQuery (necessary for Bootstrap's JavaScript plugins) -->
	<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.0/jquery.min.js"></script>
	<!-- Include all compiled plugins (below), or include individual files as needed -->
	<script src="//netdna.bootstrapcdn.com/bootstrap/3.1.1/js/bootstrap.min.js"></script>
	</body>
	</html>