046c0e5fc2
When an empty volume is mounted into a container, Docker will chown that volume appropriately for use in the container. Podman does this as well, but there are differences in the details. In Podman, a chown is presently a one-and-done deal; in Docker, it will continue so long as the volume remains empty. Mount into a dozen containers, but never add content, the chown occurs every time. The chown is also linked to copy-up; it will always occur when a copy-up occurred, despite the volume now not being empty. This PR changes our logic to (mostly) match Docker's. For some reason, the chowning also stops if the volume is chowned to root at any point. This feels like a Docker bug, but as they say, bug for bug compatible. In retrospect, using bools for NeedsChown and NeedsCopyUp was a mistake. Docker isn't actually tracking this stuff; they're just doing a copy-up and permissions change unconditionally as long as the volume is empty. They also have the two linked as one operation, seemingly, despite happening at very different times during container init. Replicating that in our stateful system is nontrivial, hence the need for the new CopiedUp field. Basically, we never want to chown a volume with contents in it, except if that data is a result of a copy-up that resulted from mounting into the current container. Tracking who did the copy-up is the easiest way to do this. Fixes #22571 Signed-off-by: Matthew Heon <matthew.heon@pm.me>
Podman Documentation
The online man pages and other documents regarding Podman can be found at Read The Docs. The man pages can be found under the Commands link on that page.
Build the Docs
Directory Structure
| Directory | |
|---|---|
| Markdown source for man pages | docs/source/markdown/ |
| man pages aliases as .so files | docs/source/markdown/links/ |
| target for output | docs/build |
| man pages | docs/build/man |
| remote linux man pages | docs/build/remote/linux |
| remote darwin man pages | docs/build/remote/darwin |
| remote windows html pages | docs/build/remote/windows |
Support files
| docs/remote-docs.sh | Read the docs/source/markdown files and format for each platform |
| docs/links-to-html.lua | pandoc filter to do aliases for html files |
| docs/use-pagetitle.lua | pandoc filter to set html document title |
Manpage Syntax
The syntax for the formatting of all man pages can be found here.
API Reference
The latest online documentation is
automatically generated by two cooperating automation systems based on committed upstream
source code. Firstly, the Cirrus-CI docs task builds
pkg/api/swagger.yaml and uploads it to a public-facing location (Google Storage Bucket -
an online service for storing unstructured data). Second, Read The Docs
reacts to the github.com repository change, building the content for the libpod documentation
site. This site includes for the API section,
some javascript which consumes the uploaded swagger.yaml file directly from the Google
Storage Bucket.
Since there are multiple systems and local cache is involved, it's possible that updates to documentation (especially the swagger/API docs) will lag by 10-or-so minutes. However, because the client (i.e. your web browser) is fetching content from multiple locations that do not share a common domain, accessing the API section may show a stack-trace similar to the following:
If reloading the page, or clearing your local cache does not fix the problem, it is
likely caused by broken metadata needed to protect clients from cross-site-scripting
style attacks. Please notify a maintainer
so they may investigate how/why the swagger.yaml file's CORS-metadata is
incorrect, or the file isn't accessible for some other reason.
Local Testing
To build standard man pages, run make docs. Results will be in docs/build/man.
To build HTMLized man pages: Assuming that you have the dependencies installed, then also install (showing Fedora in the example):
$ sudo dnf install python3-sphinx python3-recommonmark
$ pip install sphinx-markdown-tables myst_parser
(The above dependencies are current as of 2022-09-15. If you experience problems, please see requirements.txt in this directory, it will almost certainly be more up-to-date than this README.)
After that completes, cd to the docs directory in your Podman sandbox and then do make html.
You can then preview the html files in docs/build/html with:
python -m http.server 8000 --directory build/html
...and point your web browser at http://localhost:8000/