manugarg

OAuth is a widely used HTTP authentication mechanism these days. It will be nice to add some OAuth support to Cloudprober.
This feature has also been requested by the users:
https://github.com/google/cloudprober/issues/27

Main complexity in adding OAuth support is in managing the token itself: How do we get it -- from config or retrieve from 
somewhere at the runtime, how often to refresh it, etc.

Since OAuth tokens usually expire, it's not very useful to specify tokens in the config or even environment variable 
(environment variables are passed at the process at the start time). In the config, we should specify the token source
and how often to access that token source. For example, a config could look like this:

manugarg

# Generate private key for RDS
openssl genrsa -out rds.key 4096 

# Create certificate signing request config (config for CSR: [1])
cat > /tmp/csr.cnf <<END
[ req ]
default_bits = 2048
prompt = no
default_md = sha256
distinguished_name = dn