Properly update /etc/apk/repositories when the mirrors change

This is important for the binary repository scripts, so it's feasible
to test the binary package build and challenge process locally without
setting up a new chroot whenever changing the repo URLs.

Also it behaves a bit more intuitively, because it really uses the
repo URL specified on the commandline, even when the chroot is already
set up.

pmb/chroot/apk.py

@@ -18,6 +18,8 @@ along with pmbootstrap.  If not, see <http://www.gnu.org/licenses/>.
 """
 import os
 import logging
+import shlex
+
 import pmb.chroot
 import pmb.config
 import pmb.parse.apkindex
@@ -25,6 +27,53 @@ import pmb.parse.arch
 import pmb.parse.depends
 
 
+def update_repository_list(args, suffix="native", check=False):
+    """
+    Update /etc/apk/repositories, if it is outdated (when the user changed the
+    --mirror-alpine or --mirror-pmOS parameters).
+
+    :param check: This function calls it self after updating the
+                  /etc/apk/repositories file, to check if it was successful.
+                  Only for this purpose, the "check" parameter should be set to
+                  True.
+    """
+    # Skip if we already did this
+    if suffix in args.cache["apk_repository_list_updated"]:
+        return
+
+    # Read old entries or create folder structure
+    path = args.work + "/chroot_" + suffix + "/etc/apk/repositories"
+    lines_old = []
+    if os.path.exists(path):
+        # Read all old lines
+        lines_old = []
+        with open(path) as handle:
+            for line in handle:
+                lines_old.append(line[:-1])
+    else:
+        pmb.helpers.run.root(args, ["mkdir", "-p", os.path.dirname(path)],
+                             suffix)
+
+    # Up to date: Save cache, return
+    lines_new = pmb.helpers.repo.urls(args)
+    if lines_old == lines_new:
+        args.cache["apk_repository_list_updated"].append(suffix)
+        return
+
+    # Check phase: raise error when still outdated
+    if check:
+        raise RuntimeError("Failed to update: " + path)
+
+    # Update the file
+    logging.debug("(" + suffix + ") update /etc/apk/repositories")
+    if os.path.exists(path):
+        pmb.helpers.run.root(args, ["rm", path])
+    for line in lines_new:
+        pmb.helpers.run.root(args, ["sh", "-c", "echo " +
+                                    shlex.quote(line) + " >> " + path])
+    update_repository_list(args, suffix, True)
+
+
 def check_min_version(args, suffix="native"):
     """
     Check the minimum apk version, before running it the first time in the

pmb/chroot/init.py

@@ -18,7 +18,6 @@ along with pmbootstrap.  If not, see <http://www.gnu.org/licenses/>.
 """
 import logging
 import os
-import shlex
 import glob
 import filecmp
 
@@ -51,6 +50,7 @@ def init(args, suffix="native"):
         if suffix != "native":
             pmb.chroot.binfmt.register(args, arch)
         copy_resolv_conf(args, suffix)
+        pmb.chroot.apk.update_repository_list(args, suffix)
         return
 
     # Require apk-tools-static
@@ -69,19 +69,13 @@ def init(args, suffix="native"):
     pmb.helpers.run.root(args, ["ln", "-s", "/var/cache/apk", chroot +
                                 "/etc/apk/cache"])
 
-    # Copy /etc/apk/keys/ and resolv.conf
+    # Initialize /etc/apk/keys/, resolv.conf, repositories
     logging.debug(pmb.config.apk_keys_path)
     for key in glob.glob(pmb.config.apk_keys_path + "/*.pub"):
         pmb.helpers.run.root(args, ["cp", key, args.work +
                                     "/config_apk_keys/"])
     copy_resolv_conf(args, suffix)
-
-    # Write /etc/apk/repositories
-    repos_path = chroot + "/etc/apk/repositories"
-    if not os.path.exists(repos_path):
-        for line in pmb.helpers.repo.urls(args):
-            pmb.helpers.run.root(args, ["sh", "-c",
-                                        "echo " + shlex.quote(line) + " >> " + repos_path])
+    pmb.chroot.apk.update_repository_list(args, suffix)
 
     # Install alpine-base (no clean exit for non-native chroot!)
     pmb.chroot.apk_static.run(args, ["-U", "--root", chroot,

pmb/parse/arguments.py

@@ -225,6 +225,7 @@ def arguments():
                             "apkindex_files": {},
                             "apkbuild": {},
                             "apk_min_version_checked": [],
+                            "apk_repository_list_updated": [],
                             "aports_files_out_of_sync_with_git": None,
                             "find_aport": {}})