These are instructions for pulling in the latest changes from the upstream version of this library.
The `UPSTREAM_COMMIT` file tracks the upstream version that we last synced with.

_Notes:_
- Update `/path/to/your/monorepo` below to your fleet repo location
- These instructions have not been fully tested.

```bash
export FLEET_REPO=/path/to/your/monorepo
# Clone upstream
git clone https://github.com/remitly-oss/httpsig-go.git ~/httpsig-go-merge
cd ~/httpsig-go-merge

# Check out the last upstream commit we vendored
git checkout $(cat "$FLEET_REPO"/third_party/httpsig-go/UPSTREAM_COMMIT)

# Create a branch for our downstream changes
git checkout -b internal-changes

# Copy current vendored version into this working repo
rsync -a --delete "$FLEET_REPO"/third_party/httpsig-go/ ./ --exclude .git
git add .
git commit -m "Apply downstream changes"

# Fetch upstream updates and merge them
git fetch origin
git checkout main
git merge origin/main
git checkout internal-changes
git merge main   # resolve conflicts

# Copy merged result back into monorepo
rsync -a --delete ./ "$FLEET_REPO"/third_party/httpsig-go/ --exclude .git

# Record the new upstream commit. Manually double check that it matches the upstream commit.
git rev-parse origin/main > "$FLEET_REPO"/third_party/httpsig-go/UPSTREAM_COMMIT

# Commit to monorepo
cd "$FLEET_REPO"
git add third_party/httpsig-go
git commit -m "Update httpsig-go with latest upstream changes"
```