Don't ignore the (hidden) ignore files

Don’t forget to add appropriate ignore files…

  • .dockerignore when using Docker
  • .gitignore when using git
  • .gcloudignore when using Google Cloud Platform

This week, I’ve been bitten twice in not using these.

They’re hidden files and so they’re more easy to forget unfortunately.

.dockerignore

docker build ...

Without .dockerignore

Sending build context to Docker daemon  229.9MB

Because, even though Rust’s cargo creates a useful .gitignore, it doesn’t create .dockerignore and, as you as you create ./target, you’re going to take up (likely uncessary) build context space:

With .dockerignore (matching the cargo-created .gitignore):

target/

Reduces this to:

Sending build context to Docker daemon  110.1kB

It’s useful even if you’re building locally (as it’s faster) but it’s particularly useful when you’re using cloud-based build services.

.gcloudignore

In truth, I’ve not used this before but I will from hereon.

I developed a Golang Cloud Function and use the following structure:

.
├── cmd
├── firestore.png
├── function.go
├── .gcloudignore
├── .git
├── .gitignore
├── go.mod
├── go.sum
├── LICENSE
├── README.md
├── tester.json
└── .vscode

The ./cmd directory is not needed for the deployment as it’s used only for locally testing but, I also didn’t need to keep shipping the entire hidden (!) .git tree, .vscode, the PNG, README.md, LICENSE and very much not the secret (./tester.json).

So:

With ./gcloudignore:

.git/
.vscode/

cmd/

firestore.png
README.md
tester.json

That’s all!