Add resources for images (Biocontainers, Bioconda)

[joelnitta]

In the Finding containers on dockerhub lesson, there is no mention of any source of images other than Docker Hub. In fact, learners might get the impression that Docker Hub is the only online source for images.

There are at least two additional sources that are worth mentioning: Bioconda and Biocontainers. Since all Bioconda packages have a corresponding Biocontainer image, they are largely overlapping, but they each have their own search interface. The good thing about these sources is that they are all vetted and versioned, so they are generally more reliable than any "random" image you might find on Docker Hub.

[vbagadia]

I wanted to highlight what @joelnitta stated about "vetted and versioned" images and question whether directions/warnings should be more bold about image selection? Included in hello-world example?

Episode Finding Containers Images on Docker Hub does a good job explaining what to look for and what not to look for when selecting an image. Perhaps worth adding to the key points?

[joelnitta]

Thanks for the comment! Can you explain a bit more what you mean by "Included in hello-world example?" ?

[vbagadia]

To clarify, the hello-world example given in Episode Exploring and Running Containers has a user pull an image from the docker hub early on in the lesson and promises a description of docker hub later on in the lesson. When teaching this lesson, and particularly when running docker pull commands, I am suggesting an emphasis be put on verifying images before use.

[joelnitta]

I see, thanks for clarifying.

IMHO the order is OK... of all images, the "hello world" image provided by Docker should be secure, and it would be a pretty big detour at that point to go into the details of Docker Hub. I think emphasis on using images from trusted sources is fine, but the actual lesson order doesn't need to change.