Add real-life examples of Python RPM #54
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| f"Group : {hdr[rpm.RPMTAG_GROUP]}\n" | ||
| f"Size : {hdr[rpm.RPMTAG_SIZE]}\n" | ||
| f"License : {hdr[rpm.RPMTAG_LICENSE]}\n" | ||
| f"Signature : TODO\n" |
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What is the correct tag here, please?
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Strictly speaking I don't think there is "a" correct tag, depends on whether the package is signed with RSA or EdDSA.
But as most packages are signed with RSA, you can probably go with rpm.RPMTAG_RSAHEADER
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Thank you. There is also a rpm.RPMTAG_SIGPGP tag which returns a similar value. However they both look something like this:
b"\x89\x023\x04\x00\x01\x08\x00\x1d\x16!\x04\x11]\xf9\xae\xf8W\x85>\xe8D]\n\x07'p~\xa1[y\xcc\x05\x02e\xb1\x9c\xc4\x00\n\t\x10\x07'p~\xa1[y\xccF\x12\x10\x00\xab\xf7\x00\xaa0)|\x141\xa5G#!\r\xf80\x1c\xecA$\xc8\xe2\x91\xbae\xa9I\xc8\xbf\xdd\x8f[\xbegN\xb3\x14b\xb1h\xe7\x1e\xa0\x9aaDr\xd6\xd5\x98c\x19[\xdc\xf2\x84G\xb6\xafpz\xd1a\xfaD\x91\xf6\xc2\xf9C\xb5\xc4IB(\xdc#\xe1\xca\xdb:@\x08V\x9f\xdfsbB\xc3\xfe\xe8\x9b!\xba\xad\xc3Zm}d\t\xaa9L1L\xdc\x87g\xd3\x98\xa6\xe3\xb8\x91\x96\xe9\x1b\x1f\x8dv\x02r!\xec+g2\xb7%\x15>.\x06$\x94\x92\xd10\xa7\xa7\xb2\xe1\xa1\x04\xbdp\xf01\x1d\x1ca\xcam4^\xa4\x9b\xe5\r\xbd\xda\x99\x05\xedB\x88\xa5\xf6\xd5\xa9W\xa0\x081A\x90\xd0\xdf2\xdex\xe8\xba\x99\xd4\x01\x03\xb2M\xe1\x05\xb3c\xc0\x00\x91\x84Y\xab\x8eu!*\x0e\x13\x99\x1av\x8f\\e\xdf\xe2\xdf\xfe\x97\xdf\xeby\xfd\x07\xaf\x85wB\x98\x1fz\xfe\xcf\xb8\x83\xb6O\x80_\x11\x14\xac\xa6\x00|\xb5\x1b\xa2\xe3\xc1\x0c\x18\x04\xcaX\xea\x0c\xa7\xa1G\xfb#\x14:gW\x0e\xfe\xf4S\r\xa3\xc3V\x12U:gC\x08\x15\x91Q\xaev\x13Sn\r\xfe \xa7\x0e\x07*\x80\xbe-Q\xde\x8d\xfc\x90\xbf\xbep\xdf\\\x03r\xcfw\x9fW\x06\xd4mo\x87\xf5\xcdc!\x87\x872\xdeD\x12{\x00\xad,\x1f\xf8NY\x94Y\x87,T\x99\xd1TFOE\xd1\xec\x8a(z\xd0\xbf\x19\x82\xcf\xa5_\x0cj\xe52\x86\xb5\x92V\xbf'9\xab\x95\xd8\x96\x84\xc3!\xb1\xe6QX\x8a\xe9\xe2\xb2;\t\x11\x0b\x00T\t\xbbJ|\xf8\x92\xa4\xf1d\xf0+2\x1b_x\xb4\xa9\n?`P|p\x89\xbc\xca\xbc\xee\x1f\xc8\xfb\xc6\xf6\x9a\xac`\x97z\x82\xa2?(z\x91\xe2F\t\xb2\xb1!\xd0\x9c9\xd1\xc3Lo*\xa5\x81~:\x99\xa1f\x13\xf89\xd4\xac\xcc\x96\xd8\xc6Z\xe3>\xc5\xddh\xc9^\x95\xd1pA\xc3\xb1\x0e\xf3\xd0o\xed(\x85\xa9'N\xb9\x9e\xe2\x96\x1e\x9d\xb3G\xeep\xdd\xca\xe1\xea\x94j\r\x0fU\x03\x85\xf3x"
I can't figure out how to parse something like this from it
Signature : RSA/SHA256, Thu 25 Jan 2024 12:27:00 AM CET, Key ID 0727707ea15b79cc
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The signature tags are binary OpenPGP signature blobs. To get something human readable out of them, you need to parse them with something. Python gpgme bindings will do the trick no doubt, but to output something similar as rpm's 'rpm -qi ' does, you'd use rpm's queryformat engine:
print(h.format('%{rsaheader:pgpsig}'))
The .format() argument is exactly what you'd put into --queryformat, which can do all sorts of stuff: https://rpm-software-management.github.io/rpm/manual/queryformat.html
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I worked on this recently, and pysequoia can do this now! wiktor-k/pysequoia#27
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| # FIXME this snippet fails with | ||
| TypeError: 'NoneType' object cannot be interpreted as an integer | ||
| FATAL ERROR: python callback ??? failed, aborting! |
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I have never actually installed anything through the Python API so I am not sure why this fails. The snippet should IMHO be close enough though. Can you please help me fix it?
| @@ -29,6 +29,7 @@ This page attempts to track the various relevant documentation that exists for R | |||
| * [How to ensure Large File Support for tools using the rpm API](devel_doc/large_files.html) | |||
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| ## RPM Language Bindings | |||
| * [RPM Python examples](python.html) - A showcase of real-life Python RPM examples | |||
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I couldn't figure out how to build the website, so I don't know if the link is correct. IMHO it should be.
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I think real-life examples belong to https://github.com/rpm-software-management/rpm/tree/master/python/examples |
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Personally, I'd prefer them directly in the documentation (assuming the page supports syntax highlighting) but I don't object to having them in the repository you linked. But in that case, we have to improve their discoverability. For example, it would be nice if both the documentation and the Doxygen documentation could both mention it. To be honest, the python-related links in the documentation
and the Doxygen documentation which is the first google result for "python rpm API" are basically unusable for the end user. The real-life examples should be the first thing they find. |
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They should be in the main repo as proper Python files and be linked more prominently. If they are in the main repo they will also get installed locally. Let's concentrate on that first and look at how to integrate them into the docs a s a second step. We want to integrate the C API docs better anyway. So there will be some changes in that area and we can then find a nice place for these Python examples while at it. |
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Simply having a link to https://github.com/rpm-software-management/rpm/tree/master/python/examples or text linking to the single files on GH is a quick and dirty solution. We do want something better ofc but that might be a first step to make this accessible right away. |
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Sounds good. I will create a PR to https://github.com/rpm-software-management/rpm/tree/master/python/examples and we can continue there. |
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I submitted rpm-software-management/rpm#3177 |
| @@ -29,6 +29,7 @@ This page attempts to track the various relevant documentation that exists for R | |||
| * [How to ensure Large File Support for tools using the rpm API](devel_doc/large_files.html) | |||
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| ## RPM Language Bindings | |||
| * [RPM Python examples](python.html) - A showcase of real-life Python RPM examples | |||
| * [RPM Python](https://web.archive.org/web/20050320013335/http://www.ukuug.org/events/linux2004/programme/paper-PNasrat-1/rpm-python-slides/frames.html) slideset / tutorial by Paul Nasrat (2004) | |||
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It would be nice to not continue linking 20-year-old resources as well, if this new material covers the same ground.
| f"Bug URL : {hdr[rpm.RPMTAG_BUGURL]}\n" | ||
| f"Summary : {hdr[rpm.RPMTAG_SUMMARY]}\n" | ||
| f"Description :\n{hdr[rpm.RPMTAG_DESCRIPTION]}\n" | ||
| ) |
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How challenging would it be to provide an example of iterating over files in the payload, or changelog entries?
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So basically examples showing how to implement rpm -ql hello and rpm -q --changelog hello in Python? No idea, I haven't needed it so far. But I will try to add them as well.
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@dralley , see https://github.com/rpm-software-management/rpm/tree/master/python/examples for examples of iterating over the payload, and -qlv style output.
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There's no high-level API for changelogs, but iterating over them is just walking through the three header arrays the data is stored in. This dumps the raw data, for real-world example you'd probably want to pretty it up a bit:
chl = zip(h['changelogtime'], h['changelogname'], h['changelogtext'])
for item in chl:
print(item)
For merely printing, the easiest way is to let rpm do it (copy-pasted from /usr/lib/rpm/rpmpopt*, hence the case difference):
print(h.format('[* %{CHANGELOGTIME:day} %{CHANGELOGNAME}\n%{CHANGELOGTEXT}\n\n]'))
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This has moved to the RPM main repositiory. Closing here. |
See rpm-software-management/rpm-web#54 (cherry picked from commit e927be7)
See rpm-software-management/rpm-web#54 (cherry picked from commit e927be7)
After a discussion with @ffesti on DevConf, I am adding a collection of real-life examples of how Python RPM can be used.