containerd-add-mirror.sh

#! /bin/bash

# File to replace
CONFIG_FILE="/etc/containerd/config.toml"

# Ensure MIRROR_EP is set
if [ -z "$MIRROR_EP" ]; then
    echo "MIRROR_EP is not set. Exiting."
    exit 1
fi

# Backup the file
cp "$CONFIG_FILE" "$CONFIG_FILE.bak"

orig_line=$(grep "sandbox_image" "$CONFIG_FILE")
spaces=$(echo "$orig_line" | sed 's/[^ ].*//' | awk '{print length}')

# Read the entire content of the file into a variable, with newline characters preserved
content=$(<"$CONFIG_FILE")

mirror_ep_line="  endpoint = [\"$MIRROR_EP\"]"

echo "Setting the registry mirror to $MIRROR_EP."

# Function to check if any mirror settings exist
check_mirror_existence() {
    grep -q ".registry.mirrors." "$CONFIG_FILE"
}

# Only proceed if the mirror settings do not exist
if ! check_mirror_existence; then
    echo "Adding new registry mirror settings."
    new_content=$(echo "$content" | awk -v orig_line="$orig_line" -v mirror_ep_line="$mirror_ep_line" -v spaces="$spaces" -v ORS="" '{
      if (index($0, "sandbox_image") > 0) {
          indent = sprintf("%*s", spaces, "");
          print orig_line "\n";
          print indent "# Add registry mirror\n";
          print indent "[plugins.\"io.containerd.grpc.v1.cri\".registry.mirrors.\"docker.io\"]\n";
          print indent mirror_ep_line "\n";
      } else {
          print $0 "\n";
      }
    }')

    # Write the new content back to the file
    echo "$new_content" > "$CONFIG_FILE"
else
    echo "Updating existing registry mirror URL."
    # Replace existing mirror host with the new host if different
    sed -i.bak -E "s|endpoint = \[\"http(s)?://[^\"]+\"\]|endpoint = [\"$MIRROR_EP\"]|" "$CONFIG_FILE"
fi

# Restart containerd to apply changes
# Find the PID of containerd
pid=$(ps aux | grep '/usr/bin/containerd' | grep -v 'grep' | grep -v 'shim' | awk '{print $2}')

# Check if the PID was found
if [ -z "$pid" ]; then
    echo "containerd process not found."
else
    # Send SIGHUP to containerd
    kill -s HUP $pid
    echo "Sent SIGHUP to containerd with PID $pid."
fi

# After the main task is completed
if [ $? -eq 0 ]; then
    echo "Script completed successfully."
else
    echo "Script encountered an error."
fi
tail -f /dev/null