kvs3

kvs3 is a tool for managing environment configuration values. It is intended for use with aws environments and uses an s3
bucket as a general key/value store.

Installing

$ pip install kvs3

Authenticating

kvs3 assumes running in an environment with an authenticated AWS user which has the appropriate permission to read/write
values to an s3 bucket used as the key/value store. Uses boto3 authentication method hierarchy in attempting aws access.

Setting up s3

Any s3 bucket can be used, but recommend configuring a bucket with versioning and server-side encryption. Kvs3 will use
the following sources (in order) to determine the s3 bucket name:

• --bucket flag included in parameters
• shell Environment var KVS3_BUCKET
• Run $ kvs3 init and provide bucket name. Written to .kvs3 file used by kvs3 to find bucket

Usage

Writing Keys

$ kvs3 write <service> <key> <value|->

This command will write a value to a key in s3 under the service path.

Example:

$ kvs3 --bucket my-key-value-store write my-app-env min-nodes 3

Will create an object in the s3 bucket named my-key-value-store with the name my-app-env/min-nodes and the contents 3.

Listing Keys

$ kvs3 list <service>
KEY           SIZE  MODIFIED
min-nodes     3     2019-06-27 23:37:48
max-nodes     10    2019-06-30 23:28:52

list will show the key names for a given service, along with other the size in bytes of the value and the date when
the key was last modified.

Reading Keys

$ kvs3 read <service> <key>

`read` outputs the value of a single configuration key.

Setting shell environment with multiple key values

The setenv command is used as part of a deployment pipeline to setup runtime environment variables for use in a
deployment pipeline. Create a keyfile with a simple list of key values, such as:

$ cat <<EOF > env.vars
MIN_NODES
MAX_NODES
DOCKER_REGISTRY

Now, use setenv to create the output used by bash source to define Environment variables.

$ kvs3 setenv my-app-env env.vars > local.env

Results in local.env containing the following example contents:

# source my-app-env environment config  
export MIN_NODES=3
export MAX_NODES=5
export DOCKER_REGISTRY=quay.io

This file can be used $source local.env in a linux environment to create the environment configuration values used
by a deployment pipeline.