markdown-folder-to-html | markdown documents to an HTML site

First of all, I think this is more of a Linux issue as the problem seems to be on a linux-flavoured Docker container, but I'm happy to accept that I can do something to the team city config to overcome this.

I'm also not very experienced with Linux, Docker or node/npm, though I do have a lot of development experience and am very comfortable with command line interfaces in general.

We currently have Team City set up as a build server, for building a variety of projects:

• .Net Framework,
• .Net Core
• Angular CLI
• A couple of simple websites which use node packages to generate HTML from Markdown.

The server is running as a Docker container using Docker for Windows on a Windows Server box, and this is working well.
We have one Windows 10 Build agent (a VM) which is also working fine, and builds all the .Net and .Net Core stuff fine.

The simple docs site stuff primarily uses the markdown-to-html node package, so its build steps simply get all the source .md files and compile to html with markdown-to-html, plus use some other npm packages for SASS compilation and minification of js etc. No actual node code as such, just some jQuery. In order to not tie up the other agent, and because this stuff can run happily on Linux, I want to have this running on a small docker image rather than a full VM build agent somewhere.

I previously successfully used a node.js team city agent docker image (either jacobpeddk/teamcity-agent-nodejs or omez/teamcity-agent-nodejs - can't recall) which did work for a time, though I had issues with being able to install some npm packages globally in build scripts, which meant I had to get a bash terminal into the container and run some manual npm commands. I also I think had to run apt-get install zip to get a zipping step to work. This worked fine for a while (weeks).

I added some extra JS stuff to one of these simple projects, and suddenly I was getting errors when trying to build. I (perhaps stupidly) decided that this was probably due to the container having older versions of node and/or npm etc, so I attempted to update this by getting a bash shell into the container, installing nvm and updating node.js & npm.

This ended up with a rather broken container (node errors), so I thought I'd instead start again, but actually start with the jetbrains/minimal-build-agent Docker image instead, with the aim of ending up with a nice bespoke image for our needs specifically (as I couldn't find a very up-to-date pre-existing one)

I've running a Bash shell directly on the build agent container by executing this on the host: