sup

Stack Up

Stack Up is a simple deployment tool that performs given set of commands on multiple hosts in parallel. It reads Supfile, a YAML configuration file, which defines networks (groups of hosts), commands and targets.

Demo

Note: Demo is based on this example Supfile.

Installation

$ go get -u github.com/pressly/sup/cmd/sup

Usage

$ sup [OPTIONS] NETWORK COMMAND [...]

Options

Network

A group of hosts.

# Supfile

networks:
    production:
        hosts:
            - api1.example.com
            - api2.example.com
            - api3.example.com
    staging:
        # fetch dynamic list of hosts
        inventory: curl http://example.com/latest/meta-data/hostname

$ sup production COMMAND will run COMMAND on api1, api2 and api3 hosts in parallel.

Command

A shell command(s) to be run remotely.

# Supfile

commands:
    restart:
        desc: Restart example Docker container
        run: sudo docker restart example
    tail-logs:
        desc: Watch tail of Docker logs from all hosts
        run: sudo docker logs --tail=20 -f example

$ sup staging restart will restart all staging Docker containers in parallel.

$ sup production tail-logs will tail Docker logs from all production containers in parallel.

Serial command (a.k.a. Rolling Update)

serial: N constraints a command to be run on N hosts at a time at maximum. Rolling Update for free!

# Supfile

commands:
    restart:
        desc: Restart example Docker container
        run: sudo docker restart example
        serial: 2

$ sup production restart will restart all Docker containers, two at a time at maximum.

Once command (one host only)

once: true constraints a command to be run only on one host. Useful for one-time tasks.

# Supfile

commands:
    build:
        desc: Build Docker image and push to registry
        run: sudo docker build -t image:latest . && sudo docker push image:latest
        once: true # one host only
    pull:
        desc: Pull latest Docker image from registry
        run: sudo docker pull image:latest

$ sup production build pull will build Docker image on one production host only and spread it to all hosts.

Local command

Runs command always on localhost.

# Supfile

commands:
    prepare:
        desc: Prepare to upload
        local: npm run build

Upload command

Uploads files/directories to all remote hosts. Uses tar under the hood.

# Supfile

commands:
    upload:
        desc: Upload dist files to all hosts
        upload:
          - src: ./dist
            dst: /tmp/

Interactive Bash on all hosts

Do you want to interact with multiple hosts at once? Sure!

# Supfile

commands:
    bash:
        desc: Interactive Bash on all hosts
        stdin: true
        run: bash

$ sup production bash
#
# type in commands and see output from all hosts!
# ^C

Passing prepared commands to all hosts:

$ echo 'sudo apt-get update -y' | sup production bash

# or:
$ sup production bash <<< 'sudo apt-get update -y'

# or:
$ cat <<EOF | sup production bash
sudo apt-get update -y
date
uname -a
EOF

Interactive Docker Exec on all hosts

# Supfile

commands:
    exec:
        desc: Exec into Docker container on all hosts
        stdin: true
        run: sudo docker exec -i $CONTAINER bash

$ sup production exec
ps aux
strace -p 1 # trace system calls and signals on all your production hosts

Target

Target is an alias for multiple commands. Each command will be run on all hosts in parallel, sup will check return status from all hosts, and run subsequent commands on success only (thus any error on any host will interrupt the process).

# Supfile

targets:
    deploy:
        - build
        - pull
        - migrate-db-up
        - stop-rm-run
        - health
        - slack-notify
        - airbrake-notify

$ sup production deploy

is equivalent to

$ sup production build pull migrate-db-up stop-rm-run health slack-notify airbrake-notify

Supfile

See example Supfile.

Basic structure

# Supfile
---
version: 0.4

# Global environment variables
env:
  NAME: api
  IMAGE: example/api

networks:
  local:
    hosts:
      - localhost
  staging:
    hosts:
      - stg1.example.com
  production:
    hosts:
      - api1.example.com
      - api2.example.com

commands:
  echo:
    desc: Print some env vars
    run: echo $NAME $IMAGE $SUP_NETWORK
  date:
    desc: Print OS name and current date/time
    run: uname -a; date

targets:
  all:
    - echo
    - date

Default environment variables available in Supfile

• $SUP_HOST - Current host.
• $SUP_NETWORK - Current network.
• $SUP_USER - User who invoked sup command.
• $SUP_TIME - Date/time of sup command invocation.
• $SUP_ENV - Environment variables provided on sup command invocation. You can pass $SUP_ENV to another sup or docker commands in your Supfile.

Running sup from Supfile

Supfile doesn't let you import another Supfile. Instead, it lets you run sup sub-process from inside your Supfile. This is how you can structure larger projects:

./Supfile
./database/Supfile
./services/scheduler/Supfile

Top-level Supfile calls sup with Supfiles from sub-projects:

 restart-scheduler:
    desc: Restart scheduler
    local: >
      sup -f ./services/scheduler/Supfile $SUP_ENV $SUP_NETWORK restart
 db-up:
    desc: Migrate database
    local: >
      sup -f ./database/Supfile $SUP_ENV $SUP_NETWORK up

Common SSH Problem

if for some reason sup doesn't connect and you get the following error,

connecting to clients failed: connecting to remote host failed: Connect("myserver@xxx.xxx.xxx.xxx"): ssh: handshake failed: ssh: unable to authenticate, attempted methods [none publickey], no supported methods remain

it means that your ssh-agent dosen't have access to your public and private keys. in order to fix this issue, follow the below instructions:

• run the following command and make sure you have a key register with ssh-agent

ssh-add -l

if you see something like The agent has no identities. it means that you need to manually add your key to ssh-agent. in order to do that, run the following command

ssh-add ~/.ssh/id_rsa

you should now be able to use sup with your ssh key.

Development

fork it, hack it..

$ make build

create new Pull Request

We'll be happy to review & accept new Pull Requests!

License

Licensed under the MIT License.