commit adb363e8bc162d7e705054ea7108fa96af51858f
Author: Luke Childs <lukechilds123@gmail.com>
Date:   Thu Dec 22 18:53:40 2016 +0700

    Extract expired from onionoo-node-client

diff --git a/.gitignore b/.gitignore
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index 0000000..635b656
--- /dev/null
+++ b/.gitignore
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+## Node
+
+# Logs
+logs
+*.log
+npm-debug.log*
+
+# Runtime data
+pids
+*.pid
+*.seed
+*.pid.lock
+
+# Directory for instrumented libs generated by jscoverage/JSCover
+lib-cov
+
+# Coverage directory used by tools like istanbul
+coverage
+
+# nyc test coverage
+.nyc_output
+
+# Grunt intermediate storage (http://gruntjs.com/creating-plugins#storing-task-files)
+.grunt
+
+# node-waf configuration
+.lock-wscript
+
+# Compiled binary addons (http://nodejs.org/api/addons.html)
+build/Release
+
+# Dependency directories
+node_modules
+jspm_packages
+
+# Optional npm cache directory
+.npm
+
+# Optional eslint cache
+.eslintcache
+
+# Optional REPL history
+.node_repl_history
+
+## OS X
+
+*.DS_Store
+.AppleDouble
+.LSOverride
+
+# Icon must end with two \r
+Icon
+
+
+# Thumbnails
+._*
+
+# Files that might appear in the root of a volume
+.DocumentRevisions-V100
+.fseventsd
+.Spotlight-V100
+.TemporaryItems
+.Trashes
+.VolumeIcon.icns
+.com.apple.timemachine.donotpresent
+
+# Directories potentially created on remote AFP share
+.AppleDB
+.AppleDesktop
+Network Trash Folder
+Temporary Items
+.apdisk
diff --git a/.travis.yml b/.travis.yml
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index 0000000..d8b251d
--- /dev/null
+++ b/.travis.yml
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+language: node_js
+node_js: node
+script: npm run lint && npm test
+after_success: npm run coverage
+notifications:
+  email:
+    on_success: never
diff --git a/LICENSE b/LICENSE
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index 0000000..e2db8f2
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2016 Luke Childs
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
diff --git a/package.json b/package.json
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index 0000000..9913880
--- /dev/null
+++ b/package.json
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+{
+  "name": "expired",
+  "version": "0.0.1",
+  "description": "Calculate when HTTP cache headers expire",
+  "main": "src/index.js",
+  "scripts": {
+    "test": "nyc ava",
+    "lint": "snazzy",
+    "coverage": "nyc report --reporter=text-lcov | coveralls"
+  },
+  "repository": {
+    "type": "git",
+    "url": "git+https://github.com/lukechilds/expired.git"
+  },
+  "keywords": [
+    "HTTP",
+    "cache",
+    "headers",
+    "expire",
+    "expires",
+    "expirey"
+  ],
+  "author": "Luke Childs <lukechilds123@gmail.com> (http://lukechilds.co.uk)",
+  "license": "MIT",
+  "bugs": {
+    "url": "https://github.com/lukechilds/expired/issues"
+  },
+  "homepage": "https://github.com/lukechilds/expired",
+  "dependencies": {
+    "date-fns": "^1.21.1"
+  },
+  "devDependencies": {
+    "ava": "^0.17.0",
+    "coveralls": "^2.11.15",
+    "nyc": "^10.0.0",
+    "snazzy": "^5.0.0"
+  }
+}
diff --git a/src/index.js b/src/index.js
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index 0000000..6b51323
--- /dev/null
+++ b/src/index.js
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+const addSeconds = require('date-fns/add_seconds')
+
+function expired (headers) {
+  const originDate = new Date(headers.date)
+
+  // Get max age ms
+  let maxAge = headers['cache-control'] && headers['cache-control'].match(/max-age=(\d+)/)
+  maxAge = parseInt(maxAge ? maxAge[1] : 0)
+
+  // Take current age into account
+  if (headers.age) {
+    maxAge -= headers.age
+  }
+
+  // Calculate expirey date
+  return addSeconds(new Date(originDate), maxAge)
+}
+
+module.exports = expired
diff --git a/test/unit.js b/test/unit.js
new file mode 100644
index 0000000..f6a952f
--- /dev/null
+++ b/test/unit.js
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+import test from 'ava'
+import expired from '../'
+
+test('expired is a function', t => {
+  t.is(typeof expired, 'function')
+})