copr-backend: install custom mock-custom-build.cfg.j2

Fix https://github.com/fedora-copr/copr/issues/3140

roles/copr/backend/files/provision/files/mock-custom-build.cfg.j2

@@ -0,0 +1,46 @@
+include('/etc/mock/{{ chroot }}.cfg')
+config_opts['rpmbuild_networking'] = True
+config_opts['use_host_resolv'] = True
+
+{# Hotfix for https://github.com/fedora-copr/copr/issues/3140 #}
+{%- if not chroot.startswith("fedora-rawhide-") %}
+# We don't do 'dnf builddep' for the custom method, so we don't need to install
+# python3-dnf-plugins core or dnf5-plugins at all.
+config_opts["bootstrap_image_ready"] = True
+{% endif %}
+
+# Don't mixup caches with the normal mock build.
+config_opts["root"] = "copr-custom-" + config_opts["root"]
+
+# Important e.g. to keep '/script' file available across several
+# /bin/mock calls (when tmpfs_enable is on).
+config_opts['plugin_conf']['tmpfs_opts']['keep_mounted'] = True
+
+{%- for key, value in macros.items() %}
+config_opts['macros']['{{ key }}'] = '{{ value }}'
+{%- endfor %}
+
+{% if repos %}
+config_opts[f"{config_opts.package_manager}.conf"] += """
+{% for repo in repos %}
+[{{ repo["id"] }}]
+name='{{ repo["name"] }}'
+baseurl={{ repo["baseurl"] }}
+gpgcheck=0
+enabled=1
+skip_if_unavailable=0
+metadata_expire=0
+cost=1
+best=1
+
+{%- if "priority" in repo and priority is not none %}
+priority={{ repo["priority"] }}
+{%- endif %}
+
+{%- if "module_hotfixes" in repo %}
+module_hotfixes={{ repo["module_hotfixes"] }}
+{% endif -%}
+
+{% endfor %}
+"""
+{% endif %}

roles/copr/backend/files/provision/provision_builder_tasks.yml

@@ -271,3 +271,11 @@
   loop:
     - name: mock-core-configs
       version: '39.4'
+
+# Hotfix for https://github.com/fedora-copr/copr/issues/3140
+- name: Install custom mock-custom-build.cfg.j2
+  copy:
+    src: files/mock-custom-build.cfg.j2
+    dest: /etc/copr-rpmbuild/mock-custom-build.cfg.j2
+  when:
+  - prepare_base_image is not defined