[dev] Adding a switch to skip chroot rebuilds (#1622)

toolkit/Makefile

@@ -38,6 +38,7 @@ IMAGE_CACHE_SUMMARY             ?=
 INITRD_CACHE_SUMMARY            ?=
 PACKAGE_ARCHIVE                 ?=
 PACKAGE_BUILD_RETRIES           ?= 1
+REFRESH_WORKER_CHROOT           ?= y
 # Set to 0 to use the number of logical CPUs.
 CONCURRENT_PACKAGE_BUILDS       ?= 0
 # Set to 0 to print all available results.

toolkit/docs/building/building.md

@@ -52,6 +52,9 @@
       - [`REBUILD_TOOLS=...`](#rebuild_tools)
         - [`REBUILD_TOOLS=`**`n`** *(default)*](#rebuild_toolsn-default)
         - [`REBUILD_TOOLS=`**`y`**](#rebuild_toolsy)
+      - [`REFRESH_WORKER_CHROOT=...`](#refresh_worker_chroot)
+        - [`REFRESH_WORKER_CHROOT=`**`n`**](#refresh_worker_chrootn)
+        - [`REFRESH_WORKER_CHROOT=`**`y`** *(default)*](#refresh_worker_chrooty-default)
   - [All Build Targets](#all-build-targets)
   - [Reproducing a Build](#reproducing-a-build)
     - [Build Summaries](#build-summaries)
@@ -487,6 +490,20 @@ sudo make hydrate-rpms PACKAGE_ARCHIVE=./rpms.tar.gz
 
 > Build the go tools from source as needed.
 
+#### `REFRESH_WORKER_CHROOT=...`
+
+##### `REFRESH_WORKER_CHROOT=`**`n`**
+
+> If exists, don't attempt to rebuild the worker chroot, even if its build script, its manifest, or the packages it consists of have been modified in the local repository.
+
+##### `REFRESH_WORKER_CHROOT=`**`y`** *(default)*
+
+> Rebuild the worker chroot every time at least one of the following has changed:
+>
+> - worker chroot's manifest file,
+> - at least one of the RPM packages mentioned in the manifest file, or
+> - the script responsible for building the chroot.
+
 ## All Build Targets
 
 These are the useful build targets:

toolkit/scripts/tools.mk

@@ -135,16 +135,18 @@ worker_chroot_manifest = $(TOOLCHAIN_MANIFESTS_DIR)/$(worker_manifest_name)
 # the exact path of the required rpm
 # Outputs: $(RPMS_DIR)/<arch>/<name>.<arch>.rpm
 sed_regex_full_path = 's`(.*\.([^\.]+)\.rpm)`$(toolchain_rpms_dir)/\2/\1`p'
-sed_regex_arch_only = 's`(.*\.([^\.]+)\.rpm)`\2`p'
 worker_chroot_rpm_paths := $(shell sed -nr $(sed_regex_full_path) < $(worker_chroot_manifest))
 
 worker_chroot_deps := \
 	$(worker_chroot_manifest) \
 	$(worker_chroot_rpm_paths) \
-	$(toolchain_rpms) \
 	$(PKGGEN_DIR)/worker/create_worker_chroot.sh
 
+ifeq ($(REFRESH_WORKER_CHROOT),y)
 $(chroot_worker): $(worker_chroot_deps)
+else
+$(chroot_worker):
+endif
 	$(PKGGEN_DIR)/worker/create_worker_chroot.sh $(BUILD_DIR)/worker $(worker_chroot_manifest) $(toolchain_rpms_dir) $(LOGS_DIR)
 
 validate-chroot: $(go-validatechroot) $(chroot_worker)