"Helpers for copy rules" # Hints for Bazel spawn strategy COPY_EXECUTION_REQUIREMENTS = { # ----------------+----------------------------------------------------------------------------- # no-remote | Prevents the action or test from being executed remotely or cached remotely. # | This is equivalent to using both `no-remote-cache` and `no-remote-exec`. # ----------------+----------------------------------------------------------------------------- # no-remote-cache | Results in the action or test never being cached remotely (but it may # | be cached locally; it may also be executed remotely). Note: for the purposes # | of this tag, the disk-cache is considered a local cache, whereas the http # | and gRPC caches are considered remote. If a combined cache is specified # | (i.e. a cache with local and remote components), it's treated as a remote # | cache and disabled entirely unless --incompatible_remote_results_ignore_disk # | is set in which case the local components will be used. # ----------------+----------------------------------------------------------------------------- # no-remote-exec | Results in the action or test never being executed remotely (but it may be # | cached remotely). # ----------------+----------------------------------------------------------------------------- # no-cache | Results in the action or test never being cached (remotely or locally) # ----------------+----------------------------------------------------------------------------- # no-sandbox | Results in the action or test never being sandboxed; it can still be cached # | or run remotely - use no-cache or no-remote to prevent either or both of # | those. # ----------------+----------------------------------------------------------------------------- # local | Precludes the action or test from being remotely cached, remotely executed, # | or run inside the sandbox. For genrules and tests, marking the rule with the # | local = True attribute has the same effect. # ----------------+----------------------------------------------------------------------------- # See https://bazel.google.cn/reference/be/common-definitions?hl=en&authuser=0#common-attributes # # Copying file & directories is entirely IO-bound and there is no point doing this work # remotely. # # Also, remote-execution does not allow source directory inputs, see # https://github.com/bazelbuild/bazel/commit/c64421bc35214f0414e4f4226cc953e8c55fa0d2 So we must # not attempt to execute remotely in that case. # # There is also no point pulling the output file or directory from the remote cache since the # bytes to copy are already available locally. Conversely, no point in writing to the cache if # no one has any reason to check it for this action. # # Read and writing to disk cache is disabled as well primarily to reduce disk usage on the local # machine. A disk cache hit of a directory copy could be slghtly faster than a copy since the # disk cache stores the directory artifact as a single entry, but the slight performance bump # comes at the cost of heavy disk cache usage, which is an unmanaged directory that grow beyond # the bounds of the physical disk. # TODO: run benchmarks to measure the impact on copy_directory # # Sandboxing for this action is wasteful as well since there is a 1:1 mapping of input # file/directory to output file/directory and no room for non-hermetic inputs to sneak in to the # input. "no-remote": "1", "no-remote-cache": "1", "no-remote-exec": "1", "no-cache": "1", "no-sandbox": "1", "local": "1", }