ci: add netlify docs preview deploy config

.editorconfig

@@ -9,7 +9,7 @@ insert_final_newline = true
 max_line_length = 128
 trim_trailing_whitespace = true
 
-[*.{cfg,svg,yml}]
+[*.{cfg,svg,toml,yml}]
 indent_size = 2
 
 [*.{md,markdown}]

netlify.toml

@@ -0,0 +1,27 @@
+# Streamlink documentation preview config for pull requests via netlify.com
+# Some settings like PR statuses for example can only be configured via the netlify website
+
+# https://docs.netlify.com/configure-builds/file-based-configuration/#build-settings
+[build]
+  command = "pip install -U pip setuptools && pip install -e . && pip install -U -r docs-requirements.txt && make --directory=docs clean html"
+  publish = "docs/_build/html"
+  # Since production builds can't be disabled without disabling PRs as well, pushes to the master branch need to be ignored.
+  # Also ignore pull requests which don't include any changes that would alter the docs:
+  # - docs/
+  # - docs-requirements.txt
+  # - src/streamlink_cli/argparser.py
+  # https://docs.netlify.com/configure-builds/file-based-configuration/#ignore-builds
+  ignore = "[ $(git rev-parse --abbrev-ref HEAD) = master ] || git diff --quiet master HEAD docs/ docs-requirements.txt src/streamlink_cli/argparser.py"
+
+[build.environment]
+  # Set the latest natively available Python version in the Ubuntu env (currently 16.04 / Xenial)
+  # https://docs.netlify.com/configure-builds/manage-dependencies/#python
+  # https://github.com/netlify/build-image/blob/xenial/included_software.md
+  PYTHON_VERSION = "3.7"
+
+# Builds on untagged commits are always "latest", but since it's built on the root docs dir, actual "latest" links will cause 404 errors
+# https://docs.netlify.com/configure-builds/file-based-configuration/#redirects
+[[redirects]]
+  from = "/latest/*"
+  to = "/:splat"
+  status = 301