Listing 17-7 shows a simple Python script to upgrade or install a package.

Listing 17-7: rpmupgrade.py

#!/usr/bin/python

# Upgrades packages passed on the command line.

# Usage:

# python rpmupgrade.py rpm_file1.rpm rpm_file2.rpm ...

#

import rpm, os, sys

# Global file descriptor for the callback.

rpmtsCallback_fd = None

def runCallback(reason, amount, total, key, client_data):

global rpmtsCallback_fd

if reason == rpm.RPMCALLBACK_INST_OPEN_FILE:

print "Opening file. ", reason, amount, total, key, client_data

rpmtsCallback_fd = os.open(key, os.O_RDONLY)

return rpmtsCallback_fd

elif reason == rpm.RPMCALLBACK_INST_START:

print "Closing file. ", reason, amount, total, key, client_data

os.close(rpmtsCallback_fd)

def checkCallback(ts, TagN, N, EVR, Flags):

if TagN == rpm.RPMTAG_REQUIRENAME:

prev = ""

Nh = None

if N[0] == '/':

dbitag = 'basenames'

else:

dbitag = 'providename'

# What do you need to do.

if EVR:

print "Must find package [", N, "-", EVR, "]"

else:

print "Must find file [", N, "]"

if resolved:

# ts.addIntall(h, h, 'i')

return -1

return 1

def readRpmHeader(ts, filename):

""" Read an rpm header. """

fd = os.open(filename, os.O_RDONLY)

h = ts.hdrFromFdno(fd)

os.close(fd)

return h

ts = rpm.TransactionSet()

# Set to not verify DSA signatures.

ts.setVSFlags(-1)

for filename in sys.argv[1:]:

h = readRpmHeader(ts, filename)

print "Upgrading %s-%s-%s" % (h['name'], h['version'], h['release'])

ts.addInstall(h, filename, 'u')

unresolved_dependencies = ts.check(checkCallback)

if not unresolved_dependencies:

ts.order()

print "This upgrade will install:"

for te in ts:

print "%s-%s-%s" % (te.N(), te.V(), te.R())

print "Running transaction (final step)..."

ts.run(runCallback, 1)

else:

print "Error: Unresolved dependencies, transaction failed."

print unresolved_dependencies

This script expects the name of an RPM package file on the command line, and attempts to upgrade the package. (This will also install new packages.)

When you run the rpmupgrade.py script, you should see output like the following:

# rpm -q jikes

jikes-1.17-1

# python rpmupgrade.py jikes-1.18-1.i386.rpm

Upgrading jikes-1.18-1

This upgrade will install:

jikes-1.18-1

jikes-1.17-1

Running transaction (final step)...

Opening file. 4 0 0 jikes-1.18-1.i386.rpm 1

Closing file. 2 0 2854204 jikes-1.18-1.i386.rpm 1

# rpm -q jikes

jikes-1.18-1

This example shows that the package was upgraded after running the rpmupgrade.py script. Note that with an upgrade, the original package, jikes-1.17-1 in this case, is also added to the transaction set. With an install, this is not the case. That’s because the original package is removed as part of the transaction.

If you run this script as a non-root user, you will likely see an error like the following:

$ python rpmupgrade.py jikes-1.18-1.i386.rpm

Upgrading jikes-1.18-1

This upgrade will install:

jikes-1.18-1

jikes-1.17-1

Running transaction (final step)...

error: cannot get exclusive lock on /var/lib/rpm/Packages

error: cannot open Packages index using db3 - Operation not permitted (1)

error: cannot open Packages database in /var/lib/rpm

If a package has a dependency on a file such as a shared library, you will see output like the following:

# python rpmupgrade.py jikes-1.17-glibc2.2-1.i386.rpm jpilot-0_97-1_i386.rpm

Upgrading jikes-1.17-1

Upgrading jpilot-0.97-1

Must find file [ libpisock.so.3 ]

Error: Unresolved dependencies, transaction failed.

(('jpilot', '0.97', '1'), ('libpisock.so.3', None), 0, None, 0)

If a package has a dependency on another package, you will see output like the following:

# python rpmupgrade.py eruby-devel-0.9.8-2.i386.rpm

Upgrading eruby-devel-0.9.8-2

Must find package [ eruby-libs - 0.9.8 ]

Error: Unresolved dependencies, transaction failed.

(('eruby-devel', '0.9.8', '2'), ('eruby-libs', '0.9.8'), 8, None, 0)