Using Apache as a proxy for backend JavaScript (Strapi) server

I am trying to get a Strapi.io installation set up so that it works on an existing Apache site running on Port 80.

Details:

• The Strapi server is running on Port 1337.
• The Strapi server has both a front page at / and an admin panel /admin
• My Apache site is running at http://example.com on port 80

I have edited my apache configuration file and added the following lines:

ProxyPass /admin http://localhost:1337/admin
ProxyPassReverse /admin http://localhost:1337/admin

ProxyPass /api http://localhost:1337/
ProxyPassReverse /api http://localhost:1337/

Currently that works fine for the /api page, but not the admin page. On the Admin page I get the following console errors:

main.js:40 Uncaught (in promise) SyntaxError: Unexpected token < in JSON at position 0 at r (main.js:40) r @ main.js:40 Promise.then (async) u @ main.js:1 ./node_modules/strapi-helper-plugin/lib/src/app.js @ main.js:40 t @ main.js:1 (anonymous) @ main.js:1 (anonymous) @ main.js:1

main.js:45 Uncaught (in promise) SyntaxError: Unexpected token < in JSON at position 0 at t (main.js:45) t @ main.js:45 Promise.then (async) u @ main.js:1 ./node_modules/strapi-helper-plugin/lib/src/app.js @ main.js:45 a @ main.js:1 (anonymous) @ main.js:1 (anonymous) @

main.js:1 main.js:40 Uncaught (in promise) SyntaxError: Unexpected token < in JSON at position 0 at n (main.js:40)

If I refresh the page, some or all of the main.js show as admin.js. Not sure if it makes a difference:

main.js:40 Uncaught (in promise) SyntaxError: Unexpected token < in JSON at position 0 at r (main.js:40) r @ main.js:40 Promise.then (async) u @ main.js:1 ./node_modules/strapi-helper-plugin/lib/src/app.js @ main.js:40 t @ main.js:1 (anonymous) @ main.js:1 (anonymous) @ main.js:1

admin:1 Uncaught (in promise) SyntaxError: Unexpected token < in JSON at position 0 Promise.then (async) u @ main.js:1 ./node_modules/strapi-helper-plugin/lib/src/app.js @ main.js:40 t @ main.js:1 (anonymous) @ main.js:1 (anonymous) @ main.js:1

admin:1 Uncaught (in promise) SyntaxError: Unexpected token < in JSON at position 0

Why am I experiencing this problem. What do I have to do to get this working correctly with my Apache server?

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