easy_install.py 文件源码

def easy_install(self, spec, deps=False):
        tmpdir = tempfile.mkdtemp(prefix="easy_install-")
        download = None
        if not self.editable: self.install_site_py()

        try:
            if not isinstance(spec,Requirement):
                if URL_SCHEME(spec):
                    # It's a url, download it to tmpdir and process
                    self.not_editable(spec)
                    download = self.package_index.download(spec, tmpdir)
                    return self.install_item(None, download, tmpdir, deps, True)

                elif os.path.exists(spec):
                    # Existing file or directory, just process it directly
                    self.not_editable(spec)
                    return self.install_item(None, spec, tmpdir, deps, True)
                else:
                    spec = parse_requirement_arg(spec)

            self.check_editable(spec)
            dist = self.package_index.fetch_distribution(
                spec, tmpdir, self.upgrade, self.editable, not self.always_copy,
                self.local_index
            )
            if dist is None:
                msg = "Could not find suitable distribution for %r" % spec
                if self.always_copy:
                    msg+=" (--always-copy skips system and development eggs)"
                raise DistutilsError(msg)
            elif dist.precedence==DEVELOP_DIST:
                # .egg-info dists don't need installing, just process deps
                self.process_distribution(spec, dist, deps, "Using")
                return dist
            else:
                return self.install_item(spec, dist.location, tmpdir, deps)

        finally:
            if os.path.exists(tmpdir):
                rmtree(tmpdir)