Add option 'share'.

slapos/recipe/cmmi/README.txt

@@ -26,6 +26,21 @@ Supported options
     ``--prefix`` injection takes place. You can also set the ``--prefix``
     parameter explicitly in ``configure-options``.
 
+``share``
+
+    Specify the path in which this package is shared by many other
+    packages. When it's unset or blank, it means the package isn't
+    shared. Otherwise, it shared by many packages. Recipe will return
+    an empty list so that buildout will not uninstall the package when
+    uninstalling part.
+
+    In share mode, ``promises`` should be set so that recipe can tell
+    whether the package is installed. Otherwise nohting to do.
+
+    This option is experiment now. Recipe doesn't try to set prefix
+    with the valule of this opton in the configure or make command,
+    you should specify them accordingly by yourself.
+
 ``md5sum``
 
     MD5 checksum for the package file. If available the MD5
@@ -1062,6 +1077,53 @@ Look, "package" is reinstalled either:
     building package
     installing package
 
+Install share package
+=====================
+
+Use option ``share`` to install a share pacakge.
+    >>> write('buildout.cfg',
+    ... """
+    ... [buildout]
+    ... newest = false
+    ... parts = package
+    ...
+    ... [package]
+    ... recipe = slapos.recipe.cmmi
+    ... url = file://%s/package-0.0.0.tar.gz
+    ... share = /usr/local/bin
+    ... promises = ${:share}/mypackage.exe
+    ... """ % (src,))
+
+    >>> print system(buildout)
+    Uninstalling package.
+    Uninstalling package-2.
+    Installing package.
+    package: [ENV] TMP = /sample_buildout/parts/package/tmp
+    package: Extracting package to /sample_buildout/parts/package__compile__
+    configure --prefix=/sample_buildout/parts/package
+    building package
+    installing package
+    package: could not find promise "/usr/local/bin/mypackage.exe"
+
+Do nothing if one package has been installed.
+    >>> write('buildout.cfg',
+    ... """
+    ... [buildout]
+    ... newest = false
+    ... parts = package
+    ...
+    ... [package]
+    ... recipe = slapos.recipe.cmmi
+    ... url = file://%s/package-0.0.0.tar.gz
+    ... share = /usr/local/bin
+    ... promises = 
+    ... """ % (src,))
+
+    >>> print system(buildout)
+    Uninstalling package.
+    Installing package.
+    package: This shared package has been installed by other package
+
 For even more specific needs you can write your own recipe that uses
 ``slapos.recipe.cmmi`` and set the ``keep-compile-dir`` option to ``true``.
 You can then continue from where this recipe finished by reading the location

slapos/recipe/cmmi/__init__.py

@@ -44,6 +44,7 @@ class Recipe(object):
         options['url'] = options.get('url', '').strip()
         options['path'] = options.get('path', '').strip()
         options['promises'] = options.get('promises', '')
+        options['share'] = options.get('share', '').strip()
         
         # Check dependencies, all the dependent parts will be installed first. It
         # seems once part is referenced, for example, self.buildout[part], it will
@@ -181,12 +182,12 @@ class Recipe(object):
             raise zc.buildout.UserError('System error')
         return files.split()
         
-    def check_promises(self):
+    def check_promises(self, log=None):
         result = True
-        log = logging.getLogger(self.name)        
         for path in self.options['promises'].splitlines():
             if not os.path.exists(path):
                 result = False
+                if log is not None: 
                     log.warning('could not find promise "%s"' % path)
         return result
         
@@ -232,6 +233,11 @@ class Recipe(object):
         log = logging.getLogger(self.name)
         parts = []
 
+        # In share mode, do nothing if package has been installed.
+        if (not self.options['share'] == '') and self.check_promises():
+            log.info('This shared package has been installed by other package')
+            return parts
+            
         make_cmd = self.options.get('make-binary', 'make').strip()
         make_options = ' '.join(self.options.get('make-options', '').split())
         make_targets = ' '.join(self.options.get('make-targets', 'install').split())
@@ -341,7 +347,9 @@ class Recipe(object):
                 if post_install_cmd != '':
                     log.info('Executing post-install')
                     self.run(post_install_cmd)
-                if self.buildout_prefix != '' and os.path.exists(self.buildout_prefix):
+                if (self.buildout_prefix != '' 
+                        and self.options['share'] == '' 
+                        and os.path.exists(self.buildout_prefix)):
                     log.info('Getting installed file lists')
                     parts.extend(self.get_installed_files(tmp_path))
             except:
@@ -353,7 +361,7 @@ class Recipe(object):
             shutil.rmtree(tmp_path)
 
         # Check promises
-        self.check_promises()
+        self.check_promises(log)
         
         if self.options['url']:
             if self.options.get('keep-compile-dir',
@@ -366,5 +374,6 @@ class Recipe(object):
                 shutil.rmtree(compile_dir)
                 del self.options['compile-directory']
 
+        if self.options['share'] == '':
             parts.append(self.options['location'])
         return parts