dvc: Deprecation of live section.

[daavoo]

Motivation

Having a separate section named live can create confusion when introducing DVCLive to users already familiar with metrics and plots.

Apart from tracking the metrics and plots generated by DVCLive, the live section is used internally to potentially configure DVCLive (i.e. summary ) and generate an HTML report.

The configuration of the Live Python object through dvc.yaml results in having 2 ways of doing the same thing and can cause errors among users. Given that there are no internal reasons to configure the Live object through dvc.yaml, the removal of the live section would result in having a single source of truth for configuring DVCLive (the Python code).

Given that summary has been removed (#217), if the HTML generation is decoupled from the dvc.yaml and instead moved to DVCLive, the live section could be replaced with the existing metrics and plots sections without losing any features.

This would simplify the integration between DVC and DVCLive and reduce the friction for introducing DVCLive to users already familiar metrics and plots

---

Implementation

Replace:

stages:
  train:
    cmd: python train.py
    deps:
      - train.py
    live:
      training_metrics:
        summary: true
        html: true

With:

stages:
  train:
    cmd: python train.py
    deps:
      - train.py
    metrics:
      - dvclive.json:
          cache: false
    plots:
      - dvclive/scalars:
          cache: false
      - dvclive/images

---

Tasks

• html generation: make dvclive independent of dvc #213
• live: Remove html generation. dvc#7514
• exp init: Revisit type="dl" dvc#7534
• Replace usages of live with plots and metrics [docs] #229
• Need to pass output path in Python API (before it was optionally parsed from live section) [docs] #230
• Should close More granular control on caching of logs with dvclive #77