CDN Hosting at Google Cloud Storage

Note: these are preliminary notes about using Google Cloud Storage as a CDN service

Preliminaries

• The documentation home is https://developers.google.com/storage/index.
• The main tool is gsutil.
• Note: due to rapid development a lot of information on the web uses outdated syntax (but is still useful, e.g., https://gist.github.com/mhulse/4362104).

Copying

Notes:

• gsutil option: -m multithreaded (higher load+cost, faster)

• cp options: recursively (-R), compressed (-z), verbose (-v) https://developers.google.com/storage/docs/gsutil/commands/cp

    gsutil -m cp -Rzv mathjax gs://mathjax-cdn/
  

This also works within google storage, i.e., gsutil cp gs://bucket1/file1 gs://bucket2/

make bucket public

Notes:

• should only be needed once

• https://developers.google.com/storage/docs/gsutil/commands/acl#set

    gsutil -m setacl -R -a public-read gs://mathjax-cdn
  

set CORS

Notes:

• should only be needed once
• https://developers.google.com/storage/docs/cross-origin

create XML file with

<?xml version="1.0" encoding="UTF-8"?>
<CorsConfig>
  <Cors>
        <Origins>
            <Origin>*</Origin>
        </Origins>
        <Methods>
            <Method>GET</Method>
            <Method>POST</Method>
            <Method>HEAD</Method>
        </Methods>
        <ResponseHeaders>
            <ResponseHeader>*</ResponseHeader>
        </ResponseHeaders>
        <MaxAgeSec>86400</MaxAgeSec>
    </Cors>
</CorsConfig>

Save as cors.xml and run

gsutil cors set cors.xml gs://fonts.acmecompany.com/

mime-type headers

Notes:

• https://developers.google.com/storage/docs/gsutil/commands/setmeta
• the ** wildcard includes subdirectories, https://developers.google.com/storage/docs/gsutil/addlhelp/WildcardNames
• EOT and SVG content-type headers are detected correctly during upload.
• WOFF is set to the old mime type x-font/woff; that works but we decided to go with the future-proof * file bug report at Google?
• For otf: gsutil setmeta -r -h "Content-Type:font/opentype" -h "Cache-Control:public, max-age=3600" -h "Content-Disposition" gs://mathjax-cdn/mathjax/2.3-latest/fonts/HTML-CSS/**.otf
• For otf: gsutil setmeta -r -h "Content-Type:application/font-woff" -h "Cache-Control:public, max-age=3600" -h "Content-Disposition" gs://mathjax-cdn/mathjax/2.3-latest/fonts/HTML-CSS/**.woff

TODO

• tests -- we don't actually have any tests that check the functionality of the CDN.
  • CORS
  • mimetype