Cache-Control headers for S3 Static sites

s3-header-hack.sh

#!/bin/bash

### USAGE ###
## Sets $1's objects' Cache-control:max-age= header to $2.
## e.g. ./s3-header-hack.sh mybucket 60 // for 60 seconds.

s3Cmd() {
    cmd=$1;
    if type $cmd 2>/dev/null; then
        S3CMD=$cmd;
    else

        if [ ! -x /tmp/s3cmd/s3cmd ]; then
            echo "s3cmd is not installed.  Installing..." >&1

            cd /tmp/ >&1
            rm -rf s3cmd  >&1 ; # Remove existing temp install if required.
            mkdir s3cmd && cd s3cmd  >&1;

            ## I don't trust upstream repositories with my S3 keys
            ##   Instead, I checkout a pre-vetted version that I know works
            git clone https://github.com/s3tools/s3cmd.git .  >&1
            git reset --hard e7fad103ca2e485598f67a787c2789eb460dd9cb  >&1

            echo "Installed s3cmd to `pwd`" >&1
        fi
        S3CMD='python /tmp/s3cmd/s3cmd'
    fi
}

expires() {
    ## Here we get to hack around with date since OSX screws with the params
    offset=$1;
    # http://stackoverflow.com/questions/3466166/how-to-check-if-running-in-cygwin-mac-or-linux
    if [ "$(uname)" == "Darwin" ]; then
        date -u -v"+$(echo $offset)S" +"%a, %d %b %Y %H:%M:%S"
    elif [ "$(expr substr $(uname -s) 1 5)" = "Linux" ]; then
        date -u -d"+$(echo $offset) seconds" +"%a, %d %b %Y %H:%M:%S"
    elif [ "$(expr substr $(uname -s) 1 10)" == "MINGW32_NT" ]; then
        # I'm a lazy dev and officially don't support windows.
        # Perhaps a cider infused night of dev will fix this, or a kind OSS contributor instead?
        exit 1
    fi
}

s3Cmd 's3cmd' # set the S3CMD variable.
echo "Using s3cmd: $S3CMD";

offset=$2;
##expiresHeader=$(expires $offset);
##
##
##if [ $? == 1 ]; then
##    echo "Your OS is weird, fix me pl0x."
##    exit 1
##fi

## Note: env vars are set by Codeship's S3 deploy
## -s enforces HTTPS
## I'm lazy and just set everything to 60s expire.
## For historical purposes, this is fun to play with!
#### --add-header="Expires:$expiresHeader"
$S3CMD --recursive modify \
  --add-header="Cache-Control:max-age=$offset" \
  --access_key=$AWS_ACCESS_KEY_ID \
  --secret_key=$AWS_SECRET_ACCESS_KEY \
  --region=$AWS_DEFAULT_REGION \
  s3://$1/ \
  -s

echo "One day, Codeship might add meta-data control to their s3 deployments :) "