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# decapitated
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Headless ‘Chrome’ Orchestration
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## Description
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The ‘Chrome’ browser <https://www.google.com/chrome/> has a headless
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mode which can be instrumented programmatically. Tools are provided to
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perform headless ‘Chrome’ instrumentation on the command-line, including
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retrieving the javascript-executed web page, PDF output or screen shot
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of a URL.
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### IMPORTANT
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You’ll need to set an envrionment variable `HEADLESS_CHROME` to one of
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these two values:
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- Windows(32bit): `C:/Program
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Files/Google/Chrome/Application/chrome.exe`
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- Windows(64bit): `C:/Program Files
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(x86)/Google/Chrome/Application/chrome.exe`
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- macOS: `/Applications/Google\ Chrome.app/Contents/MacOS/Google\
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Chrome`
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- Linux: `/usr/bin/google-chrome`
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A guess is made (but not verified yet) if `HEADLESS_CHROME` is
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non-existent.
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It’s best to use `~/.Renviron` to store this value for the time being.
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## What’s in the tin?
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The following functions are implemented:
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- `chrome_dump_pdf`: “Print” to PDF
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- `chrome_read_html`: Read a URL via headless Chrome and return the
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raw or rendered ’
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<body>
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‘’innerHTML’ DOM elements
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- `chrome_shot`: Capture a screenshot
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- `chrome_version`: Get Chrome version
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- `get_chrome_env`: get an envrionment variable ‘HEADLESS\_CHROME’
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- `set_chrome_env`: set an envrionment variable ‘HEADLESS\_CHROME’
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## Installation
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``` r
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devtools::install_github("hrbrmstr/decapitated")
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```
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## Usage
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``` r
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library(decapitated)
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# current verison
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packageVersion("decapitated")
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```
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## [1] '0.1.0'
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``` r
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chrome_version()
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chrome_read_html("http://httpbin.org/")
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```
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## {xml_document}
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## <html>
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## [1] <head>\n<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">\n<meta http-equiv="content-type" valu ...
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## [2] <body id="manpage">\n<a href="http://github.com/kennethreitz/httpbin"><img style="position: absolute; top: 0; rig ...
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``` r
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chrome_dump_pdf("http://httpbin.org/")
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```
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``` r
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chrome_shot("http://httpbin.org/")
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## format width height colorspace filesize
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## 1 PNG 1600 1200 sRGB 215680
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```
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