You can create the equivalent of the rpm –qi command with a small number of Python commands. Listing 17-3 shows an example. This script queries for a particular package name, as shown previously in Listing 17-2. Once a package is found, though, rpminfo.py prints out a lot more information, similar to the output from the rpm –qi command.

Listing 17-3: rpminfo.py

#!/usr/bin/python

# Lists information on installed package listed on command line.

# Usage:

# python rpminfo.py package_name

import rpm, sys

def printEntry(header, label, format, extra):

value = header.sprintf(format).strip()

print "%-20s: %s %s" % (label, value, extra)

def printHeader(h):

if h[rpm.RPMTAG_SOURCEPACKAGE]:

extra = " source package"

else:

extra = " binary package"

printEntry(h, 'Package', "%{NAME}-%{VERSION}-%{RELEASE}", extra)

printEntry(h, 'Group', "%{GROUP}", '')

printEntry(h, 'Summary', "%{Summary}", '')

printEntry(h, 'Arch-OS-Platform', "%{ARCH}-%{OS}-%{PLATFORM}", '')

printEntry(h, 'Vendor', "%{Vendor}", '')

printEntry(h, 'URL', "%{URL}", '')

printEntry(h, 'Size', "%{Size}", '')

printEntry(h, 'Installed on', "%{INSTALLTID:date}", '')

print h['description']

print "Files:"

fi = h.fiFromHeader()

print fi

# Dependencies

print "Provides:"

print h.dsFromHeader('providename')

print "Requires:"

print h.dsFromHeader('requirename')

if h.dsFromHeader('obsoletename'):

print "Obsoletes:"

print h.dsFromHeader('obsoletename')

if h.dsFromHeader('conflictname'):

print "Conflicts:"

print h.dsFromHeader('conflictname')

ts = rpm.TransactionSet()

mi = ts.dbMatch( 'name', sys.argv[1] )

for h in mi:

printHeader(h)

Note

You should be able to simplify this script. The extensive use of the sprintf method is for illustration more than efficiency. You generally only need to call sprintf when you need a format modifier for a tag. In the rpminfo.py script, sprintf was also used to ensure that all entries are text, which allows for calling strip.

The printEntry function takes in a header sprintf tag value in the format of "%{NAME}". You can also pass in more complex values with multiple header entries, such as "%{NAME}-%{VERSION}".

When you run this script, you need to pass the name of a package. You'll see output like the following:

$ python rpminfo.py jikes

Package : jikes-1.18-1 binary package

Group : Development/Languages

Summary : java source to bytecode compiler

Arch-OS-Platform : i386-Linux-(none)

Vendor : (none)

URL : http://ibm.com/developerworks/opensource/jikes

Size : 2853672

Installed on : Mon Dec 2 20:10:13 2002

The IBM Jikes compiler translates Java source files to bytecode. It

also supports incremental compilation and automatic makefile

generation,and is maintained by the Jikes Project:

http://ibm.com/developerworks/opensource/jikes/

Files:

/usr/bin/jikes

/usr/doc/jikes-1.18/license.htm

/usr/man/man1/jikes.1.gz

Provides:

P jikes

P jikes = 1.18-1

Requires:

R ld-linux.so.2

R libc.so.6

R libc.so.6(GLIBC_2.0)

R libc.so.6(GLIBC_2.1)

R libc.so.6(GLIBC_2.1.3)

R libm.so.6

R libstdc++-libc6.2-2.so.3