Astro

AstroAstro

Generate a unique OG image for every page, or any on-demand graphic, from a single Imejis template. The pattern below uses an Astro API endpoint as a thin proxy: your API key stays on the server, and the browser (and social crawlers) only ever see your own URL.

Set two environment variables first: IMEJIS_API_KEY (from your dashboard) and IMEJIS_DESIGN_ID (any design's ID).

.env

IMEJIS_API_KEY=your_api_key
IMEJIS_DESIGN_ID=your_design_id

1 an endpoint that renders the image1. An endpoint that renders the image

This endpoint takes a title query param, POSTs it to Imejis as a component.property override, and returns the finished image. Because the key is sent server-side, it never reaches the client.

src/pages/og.ts

import type { APIRoute } from "astro"
 
export const GET: APIRoute = async ({ url }) => {
  const title = url.searchParams.get("title") ?? "Untitled"
 
  const res = await fetch(
    `https://render.imejis.io/v1/${import.meta.env.IMEJIS_DESIGN_ID}`,
    {
      method: "POST",
      headers: {
        "dma-api-key": import.meta.env.IMEJIS_API_KEY,
        "Content-Type": "application/json",
      },
      body: JSON.stringify({ "headline.text": title }),
    }
  )
 
  return new Response(res.body, {
    headers: {
      "Content-Type": "image/jpeg",
      // Renders are deterministic, so cache aggressively at the edge/CDN.
      "Cache-Control": "public, immutable, no-transform, max-age=31536000",
    },
  })
}

2 point your metadata at it2. Point your metadata at it

Reference the endpoint from your layout's <head>, passing each page's real data. Social platforms fetch /og?title=… from your own domain, no key exposed.

src/layouts/Layout.astro

---
const { title } = Astro.props
const ogImage = `https://your-site.com/og?title=${encodeURIComponent(title)}`
---
<head>
  <title>{title}</title>
  <meta property="og:image" content={ogImage} />
  <meta name="twitter:card" content="summary_large_image" />
  <meta name="twitter:image" content={ogImage} />
</head>

Override any field. Each dynamic component exposes keys like headline.text, title.color, or image.image. Send only the ones you want to change. A design's overridable fields are listed in its Share / API panel.