Proposal: macros and include to extend syntax

[knutov]

Spot has minimal command types and that's perfect.

Migrating a lot of code from ansible to spot I thought it could be very convenient to have more commands to have tasks more human-readable look (lower human factor, self-documented code). At the same time it's good to keep spot simple itself.

As an option, is it possible and is it good idea to add something like macros? They could be inlined during run, so it is should be easy to code.

Also possibility to include yaml from other files via 'include:' in yaml or multiple --include ... in command line (with deep merge of the structure) will add more flexibility.

It could be something like:

vars:
  chatId: 12345

macros:
  mkdir:
    type: iterate # 'iterate' to run script multiple times or 'join' to run command with all args joined via space character
    script: mkdir -p {SPOT_MACRO_ARG}
  notify:
    # new variables like {SPOT_PREV_TASK} and {SPOT_NEXT_TASK} with names of previous and next tasks could be useful
    script: |
      # some long multiline command that should be runned between tasks;
      # for example long curl query to notify to some chat about progress via http api
      curl -X POST https://crm.example.com/notify/ \
        -H 'Content-Type: application/json' \
        -d '{"task_done":"{SPOT_PREV_TASK}","task_next":"{SPOT_NEXT_TASK}", "chat_id": "$chatId", message: "{SPOT_MACRO_ARG}" }'
  cp: # just as example of custom internal vars
    script: cp "{from}" "{to}"

include: "macros/extended.yaml" # or multiple files:
# include: 
#   - "macros/one.yml"
#   - "macros/two.yml"
#   - "vendor/tasks.yml"

task:
  - name: create one dir with command in the same line
    mkdir: /path/to/dir

  - name: notify to chat
    notify: "Hurray!"

  - name: create multiple dirs
    mkdir:
      - "/path/to/dir1"
      - "/path/to/dir2"
      - "/path/to/dir3"

  - name: notify to chat
    notify: "Hurray!"

  - name: copy files
    cp:
      from: "..."
      to: "..."

  - name: notify to chat
    notify: "Hurray!"

Just as an idea.