How to include images from the epub template with pandoc?

Question

I've altered the epub template to display more information. It works fine, except when I specify images that refer to a local file. e.g. <img src = "my_file.png">. The code is there in the epub, but the image file isn't.

Answer 1

Pandoc does not parse the template as HTML, so it misses the <img> element when collecting media elements for inclusion in the EPUB. A quick and simple work-around is to list the missing images in some unused metadata field. E.g.,

---
missing-images: |
  ![](my_file.png)
---

Store the above in a file and pass it to pandoc via --metadata-file. This makes pandoc aware of the file, forcing its inclusion.

One could automate it by letting pandoc parse the template and extract the image information, e.g. with a pandoc Lua filter, but that's likely to be more trouble than it's worth.