Refactor into visitor pattern

podctl/visitors/__init__.py

@@ -0,0 +1,8 @@
+from .base import Base  # noqa
+from .config import Config  # noqa
+from .copy import Copy  # noqa
+from .packages import Packages  # noqa
+from .pip import Pip  # noqa
+from .run import Run  # noqa
+from .tag import Tag  # noqa
+from .user import User  # noqa

podctl/visitors/base.py

@@ -0,0 +1,5 @@
+
+
+class Base:
+    def __init__(self, base):
+        self.base = base

podctl/visitors/config.py

@@ -0,0 +1,7 @@
+class Config:
+    def __init__(self, **values):
+        self.values = values
+
+    def post_build(self, script):
+        for key, value in self.values.items():
+            script.config(f'--{key} {value}')

podctl/visitors/copy.py

@@ -0,0 +1,26 @@
+class Copy:
+    def __init__(self, src, dst):
+        self.src = src
+        self.dst = dst
+
+    def init_build(self, script):
+        count = self.dst.count(':')
+        self.mode = None
+        self.owner = None
+        if count == 2:
+            self.dst, self.mode, self.owner = self.dst.split(':')
+        elif count == 1:
+            self.dst, self.mode = self.dst.split(':')
+            self.owner = script.variable('user')
+
+    def build(self, script):
+        if isinstance(self.src, list):
+            script.run(f'sudo mkdir -p {self.dst}')
+            for item in self.src:
+                script.append(f'cp -a {item} $mnt{self.dst}')
+
+        if self.mode:
+            script.run(f'sudo chmod {self.mode} $mnt{self.dst}')
+
+        if self.owner:
+            script.run(f'sudo chown -R {self.owner} $mnt{self.dst}')

podctl/visitors/packages.py

@@ -0,0 +1,54 @@
+import subprocess
+
+
+class Packages:
+    mgrs = dict(
+        apk=dict(
+            update='sudo apk update',
+            upgrade='sudo apk upgrade',
+            install='sudo apk add',
+        ),
+    )
+
+    def __init__(self, *packages):
+        self.packages = list(packages)
+
+    def pre_build(self, script):
+        for mgr, cmds in self.mgrs.items():
+            cmd = [
+                'podman',
+                'run',
+                script.container.variable('base'),
+                'which',
+                mgr
+            ]
+            print('+ ' + ' '.join(cmd))
+            try:
+                subprocess.check_call(cmd)
+                self.mgr = mgr
+                self.cmds = cmds
+                break
+            except subprocess.CalledProcessError:
+                continue
+
+    def build(self, script):
+        cache = f'.cache/{self.mgr}'
+        script.mount(
+            '$(pwd)/' + cache,
+            f'/var/cache/{self.mgr}'
+        )
+
+        if self.mgr == 'apk':
+            # special step to enable apk cache
+            script.run('ln -s /var/cache/apk /etc/apk/cache')
+            script.append(f'''
+            old="$(find .cache/apk/ -name APKINDEX.* -mtime +3)"
+            if [ -n "$old" ] || ! ls .cache/apk/APKINDEX.*; then
+                {script._run(self.cmds['update'])}
+            else
+                echo Cache recent enough, skipping index update.
+            fi
+            ''')
+
+        script.run(self.cmds['upgrade'])
+        script.run(' '.join([self.cmds['install']] + self.packages))

podctl/visitors/pip.py

@@ -0,0 +1,25 @@
+class Pip:
+    def __init__(self, *pip_packages):
+        self.pip_packages = pip_packages
+
+    def build(self, script):
+        script.append(f'''
+        if {script._run("bash -c 'type pip3'")}; then
+            _pip=pip3
+        elif {script._run("bash -c 'type pip'")}; then
+            _pip=pip
+        elif {script._run("bash -c 'type pip2'")}; then
+            _pip=pip2
+        fi
+        ''')
+        script.mount('.cache/pip', '/root/.cache/pip')
+        script.run('sudo $_pip install --upgrade pip')
+        source = [p for p in self.pip_packages if p.startswith('/')]
+        if source:
+            script.run(
+                f'sudo $_pip install --upgrade --editable {" ".join(source)}'
+            )
+
+        nonsource = [p for p in self.pip_packages if not p.startswith('/')]
+        if nonsource:
+            script.run(f'sudo $_pip install --upgrade {" ".join(source)}')

podctl/visitors/run.py

@@ -0,0 +1,7 @@
+class Run:
+    def __init__(self, *commands):
+        self.commands = commands
+
+    def build(self, script):
+        for command in self.commands:
+            script.run(command)

podctl/visitors/tag.py

@@ -0,0 +1,6 @@
+class Tag:
+    def __init__(self, tag):
+        self.tag = tag
+
+    def post_build(self, script):
+        script.append(f'umounts && trap - 0 && buildah commit $ctr {self.tag}')

podctl/visitors/user.py

@@ -0,0 +1,37 @@
+from .packages import Packages
+
+
+class User:
+    """Secure the image with a user"""
+
+    def __init__(self, username, uid, home):
+        self.username = username
+        self.uid = uid
+        self.home = home
+        self.user_created = False
+
+    def init_build(self, script):
+        """Inject the Packages visitor if necessary."""
+        packages = script.container.visitor('packages')
+        if not packages:
+            index = script.container.visitors.index(self)
+            script.container.visitors.insert(index, Packages())
+
+    def pre_build(self, script):
+        """Inject the shadow package for the usermod command"""
+        if script.container.variable('mgr') == 'apk':
+            script.container.variable('packages').append('shadow')
+
+    def build(self, script):
+        script.append(f'''
+            if buildah run $ctr -- id {self.uid}; then
+                i=$(buildah run $ctr -- id -n {self.uid})
+                buildah run $ctr -- usermod --home-dir {self.home} --no-log-init {self.uid} $i
+            else
+                buildah run $ctr -- useradd --home-dir {self.home} --uid {self.uid} {self.username}
+            fi
+        ''')  # noqa
+        self.user_created = True
+
+    def post_build(self, script):
+        script.config(f'--user {self.username}')