| # Copyright 2018 The Bazel Authors. All rights reserved. |
| # |
| # Licensed under the Apache License, Version 2.0 (the "License"); |
| # you may not use this file except in compliance with the License. |
| # You may obtain a copy of the License at |
| # |
| # http://www.apache.org/licenses/LICENSE-2.0 |
| # |
| # Unless required by applicable law or agreed to in writing, software |
| # distributed under the License is distributed on an "AS IS" BASIS, |
| # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| # See the License for the specific language governing permissions and |
| # limitations under the License. |
| """Utils for manipulating external repositories, once fetched. |
| |
| ### Setup |
| |
| These utility are intended to be used by other repository rules. They |
| can be loaded as follows. |
| |
| ```python |
| load( |
| "@bazel_tools//tools/build_defs/repo:utils.bzl", |
| "workspace_and_buildfile", |
| "patch", |
| "update_attrs", |
| ) |
| ``` |
| """ |
| |
| def workspace_and_buildfile(ctx): |
| """Utility function for writing WORKSPACE and, if requested, a BUILD file. |
| |
| This rule is inteded to be used in the implementation function of a |
| repository rule. |
| It assumes the parameters `name`, `build_file`, `build_file_contents`, |
| `workspace_file`, and `workspace_file_content` to be |
| present in `ctx.attr`, the latter four possibly with value None. |
| |
| Args: |
| ctx: The repository context of the repository rule calling this utility |
| function. |
| """ |
| if ctx.attr.build_file and ctx.attr.build_file_content: |
| ctx.fail("Only one of build_file and build_file_content can be provided.") |
| |
| if ctx.attr.workspace_file and ctx.attr.workspace_file_content: |
| ctx.fail("Only one of workspace_file and workspace_file_content can be provided.") |
| |
| if ctx.attr.workspace_file: |
| ctx.file("WORKSPACE", ctx.read(ctx.attr.workspace_file)) |
| elif ctx.attr.workspace_file_content: |
| ctx.file("WORKSPACE", ctx.attr.workspace_file_content) |
| else: |
| ctx.file("WORKSPACE", "workspace(name = \"{name}\")\n".format(name = ctx.name)) |
| |
| if ctx.attr.build_file: |
| ctx.file("BUILD.bazel", ctx.read(ctx.attr.build_file)) |
| elif ctx.attr.build_file_content: |
| ctx.file("BUILD.bazel", ctx.attr.build_file_content) |
| |
| def _is_windows(ctx): |
| return ctx.os.name.lower().find("windows") != -1 |
| |
| def _use_native_patch(patch_args): |
| """If patch_args only contains -p<NUM> options, we can use the native patch implementation.""" |
| for arg in patch_args: |
| if not arg.startswith("-p"): |
| return False |
| return True |
| |
| def patch(ctx, patches = None, patch_cmds = None, patch_cmds_win = None, patch_tool = None, patch_args = None): |
| """Implementation of patching an already extracted repository. |
| |
| This rule is inteded to be used in the implementation function of |
| a repository rule. Ifthe parameters `patches`, `patch_tool`, |
| `patch_args`, `patch_cmds` and `patch_cmds_win` are not specified |
| then they are taken from `ctx.attr`. |
| |
| Args: |
| ctx: The repository context of the repository rule calling this utility |
| function. |
| patches: The patch files to apply. List of strings, Labels, or paths. |
| patch_cmds: Bash commands to run for patching, passed one at a |
| time to bash -c. List of strings |
| patch_cmds_win: Powershell commands to run for patching, passed |
| one at a time to powershell /c. List of strings. If the |
| boolean value of this parameter is false, patch_cmds will be |
| used and this parameter will be ignored. |
| patch_tool: Path of the patch tool to execute for applying |
| patches. String. |
| patch_args: Arguments to pass to the patch tool. List of strings. |
| |
| """ |
| bash_exe = ctx.os.environ["BAZEL_SH"] if "BAZEL_SH" in ctx.os.environ else "bash" |
| powershell_exe = ctx.os.environ["BAZEL_POWERSHELL"] if "BAZEL_POWERSHELL" in ctx.os.environ else "powershell.exe" |
| |
| if patches == None and hasattr(ctx.attr, "patches"): |
| patches = ctx.attr.patches |
| if patches == None: |
| patches = [] |
| |
| if patch_cmds == None and hasattr(ctx.attr, "patch_cmds"): |
| patch_cmds = ctx.attr.patch_cmds |
| if patch_cmds == None: |
| patch_cmds = [] |
| |
| if patch_cmds_win == None and hasattr(ctx.attr, "patch_cmds_win"): |
| patch_cmds_win = ctx.attr.patch_cmds_win |
| if patch_cmds_win == None: |
| patch_cmds_win = [] |
| |
| if patch_tool == None and hasattr(ctx.attr, "patch_tool"): |
| patch_tool = ctx.attr.patch_tool |
| if not patch_tool: |
| patch_tool = "patch" |
| native_patch = True |
| else: |
| native_patch = False |
| |
| if patch_args == None and hasattr(ctx.attr, "patch_args"): |
| patch_args = ctx.attr.patch_args |
| if patch_args == None: |
| patch_args = [] |
| |
| if len(patches) > 0 or len(patch_cmds) > 0: |
| ctx.report_progress("Patching repository") |
| |
| if native_patch and _use_native_patch(patch_args): |
| if patch_args: |
| strip = int(patch_args[-1][2:]) |
| else: |
| strip = 0 |
| for patchfile in patches: |
| ctx.patch(patchfile, strip) |
| else: |
| for patchfile in patches: |
| command = "{patchtool} {patch_args} < {patchfile}".format( |
| patchtool = patch_tool, |
| patchfile = ctx.path(patchfile), |
| patch_args = " ".join([ |
| "'%s'" % arg |
| for arg in patch_args |
| ]), |
| ) |
| st = ctx.execute([bash_exe, "-c", command]) |
| if st.return_code: |
| fail("Error applying patch %s:\n%s%s" % |
| (str(patchfile), st.stderr, st.stdout)) |
| |
| if _is_windows(ctx) and patch_cmds_win: |
| for cmd in patch_cmds_win: |
| st = ctx.execute([powershell_exe, "/c", cmd]) |
| if st.return_code: |
| fail("Error applying patch command %s:\n%s%s" % |
| (cmd, st.stdout, st.stderr)) |
| else: |
| for cmd in patch_cmds: |
| st = ctx.execute([bash_exe, "-c", cmd]) |
| if st.return_code: |
| fail("Error applying patch command %s:\n%s%s" % |
| (cmd, st.stdout, st.stderr)) |
| |
| def update_attrs(orig, keys, override): |
| """Utility function for altering and adding the specified attributes to a particular repository rule invocation. |
| |
| This is used to make a rule reproducible. |
| |
| Args: |
| orig: dict of actually set attributes (either explicitly or implicitly) |
| by a particular rule invocation |
| keys: complete set of attributes defined on this rule |
| override: dict of attributes to override or add to orig |
| |
| Returns: |
| dict of attributes with the keys from override inserted/updated |
| """ |
| result = {} |
| for key in keys: |
| if getattr(orig, key) != None: |
| result[key] = getattr(orig, key) |
| result["name"] = orig.name |
| result.update(override) |
| return result |
| |
| def maybe(repo_rule, name, **kwargs): |
| """Utility function for only adding a repository if it's not already present. |
| |
| This is to implement safe repositories.bzl macro documented in |
| https://docs.bazel.build/versions/master/skylark/deploying.html#dependencies. |
| |
| Args: |
| repo_rule: repository rule function. |
| name: name of the repository to create. |
| **kwargs: remaining arguments that are passed to the repo_rule function. |
| |
| Returns: |
| Nothing, defines the repository when needed as a side-effect. |
| """ |
| if not native.existing_rule(name): |
| repo_rule(name = name, **kwargs) |
| |
| def read_netrc(ctx, filename): |
| """Utility function to parse at least a basic .netrc file. |
| |
| Args: |
| ctx: The repository context of the repository rule calling this utility |
| function. |
| filename: the name of the .netrc file to read |
| |
| Returns: |
| dict mapping a machine names to a dict with the information provided |
| about them |
| """ |
| contents = ctx.read(filename) |
| |
| # Parse the file. This is mainly a token-based update of a simple state |
| # machine, but we need to keep the line structure to correctly determine |
| # the end of a `macdef` command. |
| netrc = {} |
| currentmachinename = None |
| currentmachine = {} |
| macdef = None |
| currentmacro = "" |
| cmd = None |
| for line in contents.splitlines(): |
| if line.startswith("#"): |
| # Comments start with #. Ignore these lines. |
| continue |
| elif macdef: |
| # as we're in a macro, just determine if we reached the end. |
| if line: |
| currentmacro += line + "\n" |
| else: |
| # reached end of macro, add it |
| currentmachine[macdef] = currentmacro |
| macdef = None |
| currentmacro = "" |
| else: |
| # Essentially line.split(None) which starlark does not support. |
| tokens = [ |
| w.strip() |
| for w in line.split(" ") |
| if len(w.strip()) > 0 |
| ] |
| for token in tokens: |
| if cmd: |
| # we have a command that expects another argument |
| if cmd == "machine": |
| # a new machine definition was provided, so save the |
| # old one, if present |
| if not currentmachinename == None: |
| netrc[currentmachinename] = currentmachine |
| currentmachine = {} |
| currentmachinename = token |
| elif cmd == "macdef": |
| macdef = "macdef %s" % (token,) |
| # a new macro definition; the documentation says |
| # "its contents begin with the next .netrc line [...]", |
| # so should there really be tokens left in the current |
| # line, they're not part of the macro. |
| |
| else: |
| currentmachine[cmd] = token |
| cmd = None |
| elif token in [ |
| "machine", |
| "login", |
| "password", |
| "account", |
| "macdef", |
| ]: |
| # command takes one argument |
| cmd = token |
| elif token == "default": |
| # defines the default machine; again, store old machine |
| if not currentmachinename == None: |
| netrc[currentmachinename] = currentmachine |
| |
| # We use the empty string for the default machine, as that |
| # can never be a valid hostname ("default" could be, in the |
| # default search domain). |
| currentmachinename = "" |
| currentmachine = {} |
| else: |
| fail("Unexpected token '%s' while reading %s" % |
| (token, filename)) |
| if not currentmachinename == None: |
| netrc[currentmachinename] = currentmachine |
| return netrc |
| |
| def use_netrc(netrc, urls): |
| """compute an auth dict from a parsed netrc file and a list of URLs |
| |
| Args: |
| netrc: a netrc file already parsed to a dict, e.g., as obtained from |
| read_netrc |
| urls: a list of URLs. |
| |
| Returns: |
| dict suitable as auth argument for ctx.download; more precisely, the dict |
| will map all URLs where the netrc file provides login and password to a |
| dict containing the corresponding login and passwored, as well as the |
| mapping of "type" to "basic" |
| """ |
| auth = {} |
| for url in urls: |
| schemerest = url.split("://", 1) |
| if len(schemerest) < 2: |
| continue |
| if not (schemerest[0] in ["http", "https"]): |
| # For other protocols, bazel currently does not support |
| # authentication. So ignore them. |
| continue |
| host = schemerest[1].split("/")[0].split(":")[0] |
| if not host in netrc: |
| continue |
| authforhost = netrc[host] |
| if "login" in authforhost and "password" in authforhost: |
| auth[url] = { |
| "type": "basic", |
| "login": authforhost["login"], |
| "password": authforhost["password"], |
| } |
| return auth |
