@checkly/handlebars

Checkly's Handlebars wrapper. It exposes a Handlebars instance plus create(), with a curated set of helpers:

• Custom: $RANDOM_NUMBER, $UUID, split, tagValue, startsWith, replace
• Comparison: and, or, not, eq, ne, gt, gte, lt, lte, compare, contains, has, is, isnt, ifEq, ifEven, ifOdd, ifNth, unlessEq, … (the full comparison category)
• Date: year, date, moment

const Handlebars = require('@checkly/handlebars')
Handlebars.create().compile('Bearer {{TOKEN}}')({ TOKEN: 'secret' }) // 'Bearer secret'

Handlebars.create().compile('{{tagValue TAGS "applicationname" "UNKNOWN"}}')({
  TAGS: ['team:platform', 'applicationname:api'],
}) // 'api'

Date helpers

{{moment}} and {{date}} are the same helper, backed by dayjs (moment-compatible format tokens like YYYY-MM-DD, plus the X/x unix tokens):

• {{moment}} — now, default long format (June 22, 2026)
• {{moment "YYYY-MM-DD"}} — format now with the given pattern
• {{moment "<input>" "<fmt>"}} — parse the input, format it with the pattern

The input is an absolute date (anything dayjs parses, e.g. 2020-06-15) or one of these relative phrases:

now | today | yesterday | tomorrow
<count> <unit>[s] ago              e.g. "2 days ago", "an hour ago"
[in] <count> <unit>[s] [from now]  e.g. "in a month", "3 weeks", "1 year from now"
last|next <unit>                   e.g. "next month"
<count> := a number | a | an
<unit>  := second|minute|hour|day|week|month|year

Anything else throws an error naming the input, so templating fails loudly instead of silently rendering the literal Invalid Date.

Development

TypeScript, built with tsc to dist/ (CJS + .d.ts); Biome for lint/format; Vitest for tests. All runtime deps are pinned to exact versions.

pnpm build       # tsc -> dist
pnpm test        # vitest (locks in helper behaviour — comparison/date/custom)
pnpm lint        # biome
pnpm typecheck   # tsc --noEmit