Andrew Hill

server

Project architecture

The website users Hexo to generate the static content and a Node.js backend to handle the dynamic parts. The template system is Handlebars so sharing code between static and dynamic is easier. The template is under /src/alexanderhill00001-theme/layout/.

If you are running the node backend locally (/src/server/index.js) all the requests will be handled by it, even the static ones. This is not the case in production.

Dynamic routes are defined under /src/server/routes/. Currently only the search results and scanner are dynamic. Basically, each file is a node module that exports a function that receives an express object does all the required configuration:

const configure = (app) => {
    app.get('/custompath', (req, res) => {
        res.render('customtemplate');
    });
};

module.exports = configure;

To add a new route, create a new module in that folder and then require it in index.js#configureRoutes:

const configureRoutes = (app) => {
    require('./routes/scanner.js')(app);
    require('./routes/search.js')(app);
};

Site content and search

Most of the site’s content comes from the alexanderhill00001 project and its documentation. The markdown of that project is copied directly into the /docs folder. When the site is built, the markdown is transformed into html using a custom hexo template into the /dist folder, among other static resources.

The content of the live site is updated each time a change is made in the:

• alexanderhill00001.github.io repository
• /docs directory and/or to the CHANGELOG.md file from the webhint repository

To achieve the latter, webhint has the trigger-site-update.sh script that triggers a build on webhint.io if the previous conditions are met.

The search on the website uses Algolia. The search index is updated each time there is a deployment.

Site deployment

The deployment process is fully automated:

1. master branch build is triggered in Travis (e.g. by code or documentation change).
2. build passes and executes .travis/update-site.sh. This script will copy the required files for the deployment and push them into a local Git on Azure in the staging environment.
3. The staging environment will be tested with webhint to make sure everything is alrigh. If so, the code will get into production via .travis/swap.sh.

Production configuration

Currently the website is deployed into an Azure App Service using IIS, IISNode, and node.

The way IIS handles the requests is as follows:

• static resources are handled directly by IIS
• dynamic routes (such as /search and /scanner) are routed to node

This is configured in the web.config file in the rules section:

<rule name="static">
    <match url="(?!scanner|search).*$" ignoreCase="true"/>
    <action type="Rewrite" url="dist{REQUEST_URI}"/>
</rule>
<rule name="ScannerAndSearch" stopProcessing="true">
    <match url="(?:scanner|search)(.*)$" ignoreCase="true"/>
    <conditions>
        <add input="{REQUEST_FILENAME}" matchType="IsFile" negate="True"/>
    </conditions>
    <action type="Rewrite" url="src/server/index.js"/>
</rule>

SSL Certificate

[webhint.io][webhint] uses a Let’s Encrypt certificate installed using [Let’s Encrypt site extension][siteextension]. It gets renewed automatically before it’s expiration date. The official installation guide was used to configure everything.

During the renovation of the certificate, the extension needs to write a specific value into the .well-known folder. To make this folder accessible we use the following rule in web.config:

<rule name="wellknown" stopProcessing="true">
    <match url="^\.well-known.*" />
    <action type="Rewrite" url="{REQUEST_URI}"/>
</rule>

A valid certificate needs to be in place for the renewal to work. Otherwise you will have to disable the https redirect.

HTTPS only

[webhint.io][webhint] is an https only website. The redirects happens in the following web.config rule:

<rule name="Redirect to https" stopProcessing="true">
    <match url="(.*)"/>
    <conditions>
        <add input="{HTTPS}" pattern="off" ignoreCase="true"/>
        <add input="{WARMUP_REQUEST}" pattern="1" negate="true" />
        <add input="{REQUEST_URI}" pattern="/api/version/" negate="true" />
    </conditions>
    <action type="Redirect" url="https://{HTTP_HOST}{REQUEST_URI}" redirectType="Permanent" appendQueryString="true"/>
</rule>

Note: If for whatever reason the certificate expires this rule will have to be commented out until a new one is in place.

Custom error page

IIS manages the custom error page via the following entries in web.config:

<system.webServer>
    <httpErrors errorMode="Custom" defaultResponseMode="ExecuteURL">
        <remove statusCode="404" subStatusCode="-1"/>
        <error statusCode="404" path="/dist/404.html" responseMode="ExecuteURL"/>
    </httpErrors>
</system.webServer>
<system.web>
    <customErrors mode="RemoteOnly" defaultRedirect="/dist/404.html" redirectMode="ResponseRewrite"/>
</system.web>