]> granicus.if.org Git - python/commitdiff
Added docstrings.
authorJack Jansen <jack.jansen@cwi.nl>
Mon, 10 Feb 2003 15:55:51 +0000 (15:55 +0000)
committerJack Jansen <jack.jansen@cwi.nl>
Mon, 10 Feb 2003 15:55:51 +0000 (15:55 +0000)
Lib/plat-mac/pimp.py

index e91e75b0ce96788bfc776747b54445cea0f39914..2f6ec22e30bcb8dfdc7f01f338f50553db84737e 100644 (file)
@@ -1,3 +1,17 @@
+"""Package Install Manager for Python.
+
+This is currently a MacOSX-only strawman implementation. 
+Motto: "He may be shabby, but he gets you what you need" :-) 
+
+Tools to allow easy installation of packages. The idea is that there is
+an online XML database per (platform, python-version) containing packages
+known to work with that combination. This module contains tools for getting
+and parsing the database, testing whether packages are installed, computing
+dependencies and installing packages.
+
+There is a minimal main program that works as a command line tool, but the
+intention is that the end user will use this through a GUI.
+"""
 import sys
 import os
 import urllib
@@ -6,6 +20,8 @@ import plistlib
 import distutils.util
 import md5
 
+__all__ = ["PimpPreferences", "PimpDatabase", "PimpPackage", "main"]
+
 _scriptExc_NotInstalled = "pimp._scriptExc_NotInstalled"
 _scriptExc_OldInstalled = "pimp._scriptExc_OldInstalled"
 _scriptExc_BadInstalled = "pimp._scriptExc_BadInstalled"
@@ -32,6 +48,9 @@ class MyURLopener(urllib.FancyURLopener):
                urllib.URLopener.http_error_default(self, url, fp, errcode, errmsg, headers)
 
 class PimpPreferences:
+       """Container for per-user preferences, such as the database to use
+       and where to install packages"""
+       
        def __init__(self, 
                        flavorOrder=None,
                        downloadDir=None,
@@ -55,6 +74,9 @@ class PimpPreferences:
                self.pimpDatabase = pimpDatabase
                
        def check(self):
+               """Check that the preferences make sense: directories exist and are
+               writable, the install directory is on sys.path, etc."""
+               
                rv = ""
                RWX_OK = os.R_OK|os.W_OK|os.X_OK
                if not os.path.exists(self.downloadDir):
@@ -83,6 +105,8 @@ class PimpPreferences:
                return rv                       
                
        def compareFlavors(self, left, right):
+               """Compare two flavor strings. This is part of your preferences
+               because whether the user prefers installing from source or binary is."""
                if left in self.flavorOrder:
                        if right in self.flavorOrder:
                                return cmp(self.flavorOrder.index(left), self.flavorOrder.index(right))
@@ -92,6 +116,11 @@ class PimpPreferences:
                return cmp(left, right)
                
 class PimpDatabase:
+       """Class representing a pimp database. It can actually contain
+       information from multiple databases through inclusion, but the
+       toplevel database is considered the master, as its maintainer is
+       "responsible" for the contents"""
+       
        def __init__(self, prefs):
                self._packages = []
                self.preferences = prefs
@@ -101,6 +130,10 @@ class PimpDatabase:
                self._description = ""
                
        def appendURL(self, url, included=0):
+               """Append packages from the database with the given URL.
+               Only the first database should specify included=0, so the
+               global information (maintainer, description) get stored."""
+               
                if url in self._urllist:
                        return
                self._urllist.append(url)
@@ -111,26 +144,39 @@ class PimpDatabase:
                        self._version = dict.get('version', '0.1')
                        self._maintainer = dict.get('maintainer', '')
                        self._description = dict.get('description', '')
-               self.appendPackages(dict['packages'])
+               self._appendPackages(dict['packages'])
                others = dict.get('include', [])
                for url in others:
                        self.appendURL(url, included=1)
                
-       def appendPackages(self, packages):
+       def _appendPackages(self, packages):
+               """Given a list of dictionaries containing package
+               descriptions create the PimpPackage objects and append them
+               to our internal storage."""
+               
                for p in packages:
                        pkg = PimpPackage(self, **dict(p))
                        self._packages.append(pkg)
                        
        def list(self):
+               """Return a list of all PimpPackage objects in the database."""
+               
                return self._packages
                
        def listnames(self):
+               """Return a list of names of all packages in the database."""
+               
                rv = []
                for pkg in self._packages:
                        rv.append(_fmtpackagename(pkg))
                return rv
                
        def dump(self, pathOrFile):
+               """Dump the contents of the database to an XML .plist file.
+               
+               The file can be passed as either a file object or a pathname.
+               All data, including included databases, is dumped."""
+               
                packages = []
                for pkg in self._packages:
                        packages.append(pkg.dump())
@@ -144,6 +190,13 @@ class PimpDatabase:
                plist.write(pathOrFile)
                
        def find(self, ident):
+               """Find a package. The package can be specified by name
+               or as a dictionary with name, version and flavor entries.
+               
+               Only name is obligatory. If there are multiple matches the
+               best one (higher version number, flavors ordered according to
+               users' preference) is returned."""
+               
                if type(ident) == str:
                        # Remove ( and ) for pseudo-packages
                        if ident[0] == '(' and ident[-1] == ')':
@@ -175,6 +228,8 @@ class PimpDatabase:
                return found
                
 class PimpPackage:
+       """Class representing a single package."""
+       
        def __init__(self, db, name, 
                        version=None,
                        flavor=None,
@@ -200,6 +255,7 @@ class PimpPackage:
                self._MD5Sum = MD5Sum
                
        def dump(self):
+               """Return a dict object containing the information on the package."""
                dict = {
                        'name': self.name,
                        }
@@ -226,15 +282,24 @@ class PimpPackage:
                return dict
                
        def __cmp__(self, other):
+               """Compare two packages, where the "better" package sorts lower."""
+               
                if not isinstance(other, PimpPackage):
                        return cmp(id(self), id(other))
                if self.name != other.name:
                        return cmp(self.name, other.name)
                if self.version != other.version:
-                       return cmp(self.version, other.version)
+                       return -cmp(self.version, other.version)
                return self._db.preferences.compareFlavors(self.flavor, other.flavor)
                
        def installed(self):
+               """Test wheter the package is installed.
+               
+               Returns two values: a status indicator which is one of
+               "yes", "no", "old" (an older version is installed) or "bad"
+               (something went wrong during the install test) and a human
+               readable string which may contain more details."""
+               
                namespace = {
                        "NotInstalled": _scriptExc_NotInstalled,
                        "OldInstalled": _scriptExc_OldInstalled,
@@ -259,6 +324,14 @@ class PimpPackage:
                return "yes", ""
                
        def prerequisites(self):
+               """Return a list of prerequisites for this package.
+               
+               The list contains 2-tuples, of which the first item is either
+               a PimpPackage object or None, and the second is a descriptive
+               string. The first item can be None if this package depends on
+               something that isn't pimp-installable, in which case the descriptive
+               string should tell the user what to do."""
+               
                rv = []
                if not self.downloadURL:
                        return [(None, "This package needs to be installed manually")]
@@ -278,6 +351,8 @@ class PimpPackage:
                return rv
                        
        def _cmd(self, output, dir, *cmditems):
+               """Internal routine to run a shell command in a given directory."""
+               
                cmd = ("cd \"%s\"; " % dir) + " ".join(cmditems)
                if output:
                        output.write("+ %s\n" % cmd)
@@ -293,7 +368,18 @@ class PimpPackage:
                rv = fp.close()
                return rv
                
-       def downloadSinglePackage(self, output):
+       def downloadSinglePackage(self, output=None):
+               """Download a single package, if needed.
+               
+               An MD5 signature is used to determine whether download is needed,
+               and to test that we actually downloaded what we expected.
+               If output is given it is a file-like object that will receive a log
+               of what happens.
+               
+               If anything unforeseen happened the method returns an error message
+               string.
+               """
+               
                scheme, loc, path, query, frag = urlparse.urlsplit(self.downloadURL)
                path = urllib.url2pathname(path)
                filename = os.path.split(path)[1]
@@ -312,6 +398,8 @@ class PimpPackage:
                        return "archive does not have correct MD5 checksum"
                        
        def _archiveOK(self):
+               """Test an archive. It should exist and the MD5 checksum should be correct."""
+               
                if not os.path.exists(self.archiveFilename):
                        return 0
                if not self._MD5Sum:
@@ -321,7 +409,9 @@ class PimpPackage:
                checksum = md5.new(data).hexdigest()
                return checksum == self._MD5Sum
                        
-       def unpackSinglePackage(self, output):
+       def unpackSinglePackage(self, output=None):
+               """Unpack a downloaded package archive."""
+               
                filename = os.path.split(self.archiveFilename)[1]
                for ext, cmd in ARCHIVE_FORMATS:
                        if filename[-len(ext):] == ext:
@@ -337,7 +427,12 @@ class PimpPackage:
                if not os.path.exists(setupname) and not NO_EXECUTE:
                        return "no setup.py found after unpack of archive"
                        
-       def installSinglePackage(self, output):
+       def installSinglePackage(self, output=None):
+               """Download, unpack and install a single package.
+               
+               If output is given it should be a file-like object and it
+               will receive a log of what happened."""
+               
                if not self.downloadURL:
                        return "%s: This package needs to be installed manually" % _fmtpackagename(self)
                msg = self.downloadSinglePackage(output)
@@ -359,6 +454,9 @@ class PimpPackage:
                return None
 
 class PimpInstaller:
+       """Installer engine: computes dependencies and installs
+       packages in the right order."""
+       
        def __init__(self, db):
                self._todo = []
                self._db = db
@@ -374,6 +472,12 @@ class PimpInstaller:
                                self._todo.insert(0, package)
                        
        def _prepareInstall(self, package, force=0, recursive=1):
+               """Internal routine, recursive engine for prepareInstall.
+               
+               Test whether the package is installed and (if not installed
+               or if force==1) prepend it to the temporary todo list and
+               call ourselves recursively on all prerequisites."""
+               
                if not force:
                        status, message = package.installed()
                        if status == "yes":
@@ -391,6 +495,15 @@ class PimpInstaller:
                                self._curmessages.append("Requires: %s" % descr)
                                
        def prepareInstall(self, package, force=0, recursive=1):
+               """Prepare installation of a package.
+               
+               If the package is already installed and force is false nothing
+               is done. If recursive is true prerequisites are installed first.
+               
+               Returns a list of packages (to be passed to install) and a list
+               of messages of any problems encountered.
+               """
+               
                self._curtodo = []
                self._curmessages = []
                self._prepareInstall(package, force, recursive)
@@ -400,6 +513,8 @@ class PimpInstaller:
                return rv
                
        def install(self, packages, output):
+               """Install a list of packages."""
+               
                self._addPackages(packages)
                status = []
                for pkg in self._todo:
@@ -410,6 +525,11 @@ class PimpInstaller:
                
                
 def _fmtpackagename(dict):
+       """Return the full name "name-version-flavor" of a package.
+       
+       If the package is a pseudo-package, something that cannot be
+       installed through pimp, return the name in (parentheses)."""
+       
        if isinstance(dict, PimpPackage):
                dict = dict.dump()
        rv = dict['name']
@@ -423,6 +543,8 @@ def _fmtpackagename(dict):
        return rv
        
 def _run(mode, verbose, force, args):
+       """Engine for the main program"""
+       
        prefs = PimpPreferences()
        prefs.check()
        db = PimpDatabase(prefs)
@@ -495,6 +617,8 @@ def _run(mode, verbose, force, args):
                                                print "\t", m
 
 def main():
+       """Minimal commandline tool to drive pimp."""
+       
        import getopt
        def _help():
                print "Usage: pimp [-v] -s [package ...]  List installed status"