install.sh

#!/bin/sh
# PowDNS, a minimal DNS wildcard server based on Pow (pow.cx)


# Set up the environment. Respect $VERSION if it's set.

      set -e
      POW_ROOT="$HOME/Library/Application Support/Pow"
      NODE_BIN="$POW_ROOT/Current/bin/node"
      POW_BIN="$POW_ROOT/Current/bin/pow"
      [[ -z "$VERSION" ]] && VERSION=0.4.0


# Fail fast if we're not on OS X >= 10.6.0.

      if [ "$(uname -s)" != "Darwin" ]; then
        echo "Sorry, Pow requires Mac OS X to run." >&2
        exit 1
      elif [ "$(expr "$(sw_vers -productVersion | cut -f 2 -d .)" \>= 6)" = 0 ]; then
        echo "Pow requires Mac OS X 10.6 or later." >&2
        exit 1
      fi

      echo "*** Installing Pow $VERSION..."


# Create the Pow directory structure if it doesn't already exist.

      mkdir -p "$POW_ROOT/Versions"


# If the requested version of Pow is already installed, remove it first.

      cd "$POW_ROOT/Versions"
      rm -rf "$POW_ROOT/Versions/$VERSION"


# Download the requested version of Pow and unpack it.

      curl -s http://get.pow.cx/versions/$VERSION.tar.gz | tar xzf -


# Update the Current symlink to point to the new version.

      cd "$POW_ROOT"
      rm -f Current
      ln -s Versions/$VERSION Current


# Install local configuration files.

      echo "*** Installing local configuration files..."
      "$NODE_BIN" "$POW_BIN" --install-local


# Check to see whether we need root privileges.

      "$NODE_BIN" "$POW_BIN" --install-system --dry-run >/dev/null && NEEDS_ROOT=0 || NEEDS_ROOT=1


# Install system configuration files, if necessary. (Avoid sudo otherwise.)

      if [ $NEEDS_ROOT -eq 1 ]; then
        echo "*** Installing system configuration files as root..."
        sudo -E "$NODE_BIN" "$POW_BIN" --install-system
      fi


# Start (or restart) Pow.

      echo "*** Starting the PowDNS server..."
      launchctl unload "$HOME/Library/LaunchAgents/cx.pow.powd.plist" 2>/dev/null || true
      launchctl load -Fw "$HOME/Library/LaunchAgents/cx.pow.powd.plist" 2>/dev/null


# Show a message about where to go for help.

      function print_troubleshooting_instructions() {
        echo
        echo "For troubleshooting instructions, please see the Pow wiki:"
        echo "https://github.com/37signals/pow/wiki/Troubleshooting"
        echo
        echo "To uninstall PowDNS, \`curl get.pow.cx/uninstall.sh | sh\`"
      }


# Check to see if the server is running properly.

      # If this version of Pow supports the --print-config option,
      # source the configuration and use it to run a self-test.
      CONFIG=$("$NODE_BIN" "$POW_BIN" --print-config 2>/dev/null || true)

      if [[ -n "$CONFIG" ]]; then
        eval "$CONFIG"
        echo "*** Performing self-test..."

        # Attempt to connect to Pow via each configured domain. If a
        # domain is inaccessible, try to force a reload of OS X's
        # network configuration.
        function check_domains() {
          for domain in ${POW_DOMAINS//,/$IFS}; do
            echo | nc "${domain}." "80" 2>/dev/null || return 1
          done
        }

        # Use networksetup(8) to create a temporary network location,
        # switch to it, switch back to the original location, then
        # delete the temporary location. This forces reloading of the
        # system network configuration.
        function reload_network_configuration() {
          echo "*** Reloading system network configuration..."
          local location=$(networksetup -getcurrentlocation)
          sudo networksetup -createlocation "pow$$" >/dev/null 2>&1
          sudo networksetup -switchtolocation "pow$$" >/dev/null 2>&1
          sudo networksetup -switchtolocation "$location" >/dev/null 2>&1
          sudo networksetup -deletelocation "pow$$" >/dev/null 2>&1
        }

        # Try resolving and connecting to each configured domain. If
        # it doesn't work, reload the network configuration and try
        # again. Bail if it fails the second time.
        check_domains || {
          { reload_network_configuration && check_domains; } || {
            echo "!!! Couldn't resolve configured domains ($POW_DOMAINS)"
            print_troubleshooting_instructions
            exit 1
          }
        }
      fi


# All done!

      echo "*** Installed"
      print_troubleshooting_instructions