hof-middleware

A collection of commonly used HOF middleware, exports cookies, notFound, and errors on middleware

Arranging the middleware in your app

Cookies middleware should be placed before any other routes, this guarantees that any data gathered in the form will be saved to the session. The Not Found middleware should be placed after all routes and before the Error handler middleware. This arrangement ensures that if an error is thrown it will be caught.

Cookies

Usage

app.use(require('hof-middleware').cookies({
  'cookie-name': 'my-application-cookie',
  'param-name': 'my-query-param'
}));

This middleware must be declared before your other routes.

Options

The cookie-name can be the same as your session cookie. (The middleware will not overwrite it.) Defaults to hof-cookie-check.

The param-name should be chosen so that it does not clash with names you are using elsewhere. In almost all cases the default value of hof-cookie-check will suffice.

The error raised when cookies are not supported by the client can then be handled in you error handler by identifying it using its code property which will be set to NO_COOKIES.

You can also provide an array of healthcheck URLs with healthcheckUrls, should you not want to throw a Cookies required error when requesting the app with specific URLs. Kubernetes healthcheck URLs are provided as defaults if no overrides are supplied.

Not found (404)

Expects there to be a view called 404 in your configured /views directory

Usage

app.use(require('hof-middleware').notFound({
  logger: require('/logger'),
  translate: require('hof').i18n({path: path_to_translations/__lng__/__ns__.json}).translate
}));

This middleware should be declared after your other routes but before your errorhandler.

Options

logger can be any object with a warn method.

translate can be the HOF i18n translate function

Errors

Usage

app.use(require('hof-middleware').errors({
  logger: require('/logger'),
  translate: require('hof').i18n({path: path_to_translations/__lng__/__ns__.json}).translate,
  debug: true
}));

This middleware must be declared after your other routes.

Options

logger can be any object with an error method.

translate can be the HOF i18n translate function

debug set to true will present the stack trace in the form and return the err as the content of the template.

Note If debug === true translations will not be served, but the error handler default messages

Deep translate

deepTranslate middleware supports nested conditional translations in order to show different content in different scenarios. The middleware adds a translate function to req which is used in various points throughout the architecture. This middleware must be applied before any other middleware which rely on the req.translate function. Also when initializing the form wizard, or template mixins, if a translate function is provided, this will be used rather than the deepTranslate middleware.

Usage

const i18nFuture = require('hof').i18n;
const i18n = i18nFuture({
  path: path.resolve(__dirname, './path/to/translations')
})
app.use(require('hof-middleware').deepTranslate({
  translate: i18n.translate.bind(i18n)
}));

locales

"fields": {
    "field-name": {
        "label": {
            "dependent-field": {
                "value-1": {
                    "dependent-field-2": {
                        "value-1": "Label 1",
                        "value-2": "Label 2"
                    }
                },
                "value-2": "Label 3"
            },
            "default": "Fallback label"
        }
    }
}

Using the translation key fields.field-name.label will return different values in different situations depending on the values of named fields. In the above example the following are true:

• If both dependent-field and dependent-field-2 have the value "value-1", the label returned will be "Label 1".
• If the value of dependent-field is "value-1" and the value of dependent-field-2 is "value-2", the label returned will be "Label 2".
• If the value of dependent-field is "value-2" the label returned will be "Label 3" regardless of the value of dependent-field-2
• The default label "Fallback label" will be used if value of dependent-field is neither of the given options, or it is undefined. It will also be used if the value of dependent-field is "value-1" and the value of dependent-field-2 is neither of the given options or it is undefined.