Bazel macro example. Setting up a WORKSPACE.

• Bazel macro example The WORKSPACE file is already disabled in Bazel 8 (late 2024) and will be removed in Bazel 9 (late 2025). Additional query reference This mechanism can also be used to join diamonds. The list of "library" targets to be aggregated into this target. Represents a configuration transition across a dependency edge. Bazel extensions are files ending in . Some Imagine that you need to run a tool as part of your build. It also describes the output formats bazel query supports. Macros are suitable for simple tasks. Label resolution in macros. 1 · 8. By A collection of examples of how to use the Bazel build system. This can be used, for example, for a multiplatform library that automatically chooses the appropriate implementation for the I have two macros/targets: component and bundle (which packages several components). Luckily, there is a Bazel extension for building Rust projects: rules_rust. For example, if //package:foo depends on //package:bar with a configuration transition, then the configuration of //package:bar (and its dependencies) will be //package:foo's configuration plus the changes Report an issue open_in_new View source open_in_new Nightly · 8. In this tutorial, you are Currently i need to change my . For example, bundling the application with rules_webpack Example of using Bazel to cross compile a library that depends on a procedural macro - wildarch/bazel_proc_macro_example Some of these examples are explained also in the presentation Introduction to Bazel to build C++ and Python. existing_rules()-based legacy macro will also be unable to see such a target. Readme About Bazel Getting started User guide Reference Extending Community Versioned docs 8. Tests should be in a matching Send feedback Macros Stay organized with collections Save and categorize content based on your preferences. Imagine that you need to run a tool as part of your build. This section uses the terms macro and rule interchangeably when referring Report an issue open_in_new View source open_in_new Nightly · 8. Bazel's BUILD and . Important: Transitions have memory and performance impact. For example, docker builds are easier to accomplish . Report an issue open_in_new View source open_in_new Nightly 8. 6 7. Skip to content. A configuration transition maps the transformation from one configured target to another within the build graph. This page covers the basics of using macros and includes typical use cases, debugging, and conventions. Intro # Bazel’s evaluation model includes three phases: As a contrived but simple example, let’s create a macro that will provide a reasonable default for the name of the output file. h. cc"], visibility = visibility,). A unique name for this target. Docker images can be generated with different rules. See general comments about deps at Typical attributes defined by most build rules. This page is an overview of Starlark, formerly known as Skylark, the language used in Bazel. . 0 License, and code samples are licensed under the Apache 2. Rules give you more Under the hood the tools will be the same as Angular Architect but now coordinated by Bazel. For macros, a related function, native. For example, you may want to generate or preprocess a source file, or compress a binary. proto changes) using Bazel? Using Labels to Identify and Build Specific Targets. In this tutorial, you are going to create a symbolic macro that resizes an image. blacklisted_protos: List of labels; default is []. Before learning the more advanced concepts, first: For example, target G is normally built with copts = []. While the Bazel user guide and user manual preach the benefits of giving Bazel full control over your build process by rewriting all Some things to keep in mind when writing genrules: A genrule needs to know all its input files and output files (srcs and outs attributes)It needs to know the tools it's going to use in the command (exec_tools attribute). For practical use cases, see the Bazel Query How-To. The implementation function should then call Configurable build attributes. If the input is already a Label, it is returned unchanged. Rules give you more For example, consider rules_k8s, the Kubernetes rules for Bazel. Many Bazel commands accept a list of target patterns as arguments, and they all honor the prefix negation operator -. In this tutorial, we are For example, you may want to generate or preprocess a source file, or compress a binary. For a language details and --output flag details, please see the reference manuals, Bazel query reference and Bazel cquery reference. bzl files by calling the macro() function with two required parameters: attrs and implementation. 4 A context object that is passed to the implementation function for a rule or aspect. This can be used, for example, for a multiplatform library that automatically chooses the appropriate implementation for the architecture, or for a feature-configurable binary that can be customized The default visibility of the top-level rule targets and symbolic macros in this package — that is, the targets and symbolic macros that are not themselves declared inside a symbolic macro. proto files that are already linked into proto runtimes, such as any. Recommended rules. 4 · 7. Using bzlmod; How to generate source code from a rule and include it in a library; [Macro writing] Using Symbolic Macros; CI: About. query, by contrast, runs over the results of Bazel's loading phase, Understand concepts like rules and macros to extend Bazel's capabilities. To override a declared repository with a local repository from the command line, use the --override_repository flag. For example, //foo/bar specifies the package having that name and which lives in the same repository as the package group. Configurable attributes, commonly known as select(), is a Bazel feature that lets users toggle the values of BUILD rule attributes at the command line. These tools can be other things that need to be built, like binary targets (cc_binary, java_binary, sh_binary, py_binary, etc), or they can be pre-compiled I'm using Bazel and Google's protocol buffers. 0 License. Examples for Bazel bazel. command_line Report an issue open_in_new View source open_in_new Nightly · 8. Load visibility Report an issue open_in_new View source open_in_new Nightly · 8. Rules give you more For example, you may want to generate or preprocess a source file, or compress a binary. List of examples: Bazel with third party dependencies; Basic C++ example; Basic code coverage computation for C++; Basic Python example; Bazel Macros: Generate cpp files using Python; Explicitly declare autodetected C++ toolchain when Attributes; name: Name; required. However, an Symbolic macros are available by default in Bazel 8. If target P depends on target G, and I run bazel build :P, I want both targets to be built with copts = You might want to create macros to bundle the wrapper rules along with the corresponding cc_library. package_relative_label(), converts the input into a Label in the context of the package currently being constructed. This can be used, for example, for a multiplatform library that automatically chooses the appropriate implementation for the def my_macro (name, visibility = None): native. If you need to support older Bazel versions take a look at Creating a Legacy Macro. However, an Report an issue open_in_new View source open_in_new Nightly · 8. 0. Setting up a WORKSPACE. Save and categorize content based on your preferences. Report an issue open_in_new View source open_in_new Nightly · 8. I would like to extend the bundle macro to accept a list of bundles in addition to a list of components and package all of the components directly-included or included in one of its included bundles. Invoking this value during package construction time will instantiate the macro, and cause the macro's implementation function to be evaluated (in a separate context, different from the Calls to rules and macros. bzl files, and not in BUILD files. General. Transitions define configuration changes between rules. Attributes Represents a configuration transition across a dependency edge. The exact variable names expanded is an unstable API and is subject to change. While this attribute is currently optional, it will become required when the Python rules are moved out of Bazel itself. Use; Predefined variables; Predefined genrule variables; Predefined source/output path variables; Custom variables "Make" variables are a special class of expandable string variables available to attributes marked as "Subject to 'Make variable' substitution". Rules give Report an issue open_in_new View source open_in_new Nightly · 8. You can do things like taking in the attributes you care about and creating the rule ( bazel_rule in your example) within the macro, so that the macro has the attribute value, but this Label Label(input). This page covers basic style guidelines for Starlark and also includes information on macros and rules. Use a load statement to import a symbol from an extension. proto files. Starlark is a language that defines how software is built, and as such it is both a programming and a configuration language. Overview Rules Symbolic macros Legacy macros Depsets Aspects Repository rules Example rules Distributing rules Share your custom rules to your project or the Bazel community. Enabling this flag is equivalent to using --config=linux on Linux, --config=windows on Windows, etc. The Bazel ecosystem has a growing and evolving set of rules to support popular languages and packages. A label is a unique identifier that points to a The inclusion checking rules only apply to direct inclusions. For the authoritative specification Report an issue open_in_new View source open_in_new Nightly · 8. A rule defines a series of actions that Bazel performs on inputs to produce a set of outputs, which are referenced in providers returned by the rule's implementation function. Symbolic macros are available by default in Bazel 8. Defining. This page is the reference manual for the Bazel Query Language used when you use bazel query to analyze build dependencies. 2 A callable Starlark value representing a symbolic macro; in other words, the return value of macro(). @bazel_skylib~1. For example, foo/bar/wiz is equivalent to //foo/bar:wiz (if there is a package foo/bar) or to //foo:bar/wiz (if there is a package foo). proto_library is a language-agnostic rule that describes relations between . Our front-end code is built and tested using a set of custom Bazel macros built on top of rules provided by the rules_js and rules_ts rulesets. For . This page covers how to get started using Bazel's query language to trace dependencies in your code. Due to the shortcomings of WORKSPACE, Bzlmod is replacing the legacy WORKSPACE system. cc is allowed to include bar. A macro is a function called from the BUILD file that can instantiate rules. Example: An IR conversion with a top entity The first line of the WORKSPACE file gives the project a name, and the rest loads the dependencies on rules_go and Gazelle. For example, if I have the following BUILD file: java_library (name = "directory-name", srcs = glob (["*. cc %. You can get help by Report an issue open_in_new View source open_in_new Nightly · 8. This can be used, for example, for a multiplatform library that automatically chooses the appropriate implementation for the For example, you may want to generate or preprocess a source file, or compress a binary. $< How can I accomplish the same (i. Converts the input string into a Label object, in the context of the package currently being initialized (that is, the BUILD file for which the current macro is executing). In this Report an issue open_in_new View source open_in_new Nightly · 8. generate the API whenever mymessage. You can use an outgoing-edge user-defined transition as detailed in Brian's answer, but one thing to note is that if the test target is built / run on its own (as a top-level target explicitly, or captured by a target pattern like //, //:all, //:*, or if a target depends on it directly), then it won't get the configuration transition. Overriding repositories from the command line. For example, a C++ binary rule might: Take a set of . deps: List of labels; default is []. Suppose we have the following target: In this example, a “docs” target is created, just as though the macro were a standard, single Bazel rule. cquery is a variant of query that correctly handles select() and build options' effects on the build graph. package_relative_label(input). If you want to do anything more complicated, for example add support for a new programming language, consider creating a rule. This attribute should be used to list other sh_library rules that provide interpreted program source code depended on For example, a JUnit test method would be named testFoo. For example, if //package:foo depends on //package:bar with a configuration transition, then the configuration of these two targets will differ: //package:bar's transition will be determined by that of //package:foo, as subject to the function defined by a transition object. cpp file to include #define to enable this macro. In this tutorial, you are going to create a legacy macro that resizes an image. 0 6. Much of Bazel's strength comes from the ability to define new rules that can be used by others. 3) For module extension repos: module_name~version~extension_name~repo_name (Example. This function may only be called while evaluating a BUILD file and the macros it directly or indirectly calls; it Report an issue open_in_new View source open_in_new Nightly · 8. The API will become more stable when the Python rules are moved out of Report an issue open_in_new View source open_in_new Nightly 8. proto. Note, however, that a native. Then: the macro which generates the test and target under test should should be named _test_foo (_test_provider_contents) its test rule type should be named foo_test (provider_contents_test) the label of the target of this rule type should be foo_test (provider_contents_test) For an example, consider rules_k8s, the Kubernetes rules for Bazel. 5 · 7. Suppose you have the following target: In this example, a "docs" target is created, just as though the macro were a standard, single Bazel rule. Bazel 5 deprecation. If you use an incoming-edge transition, you can put a For example, consider rules_k8s, the Kubernetes rules for Bazel. rs scripts, automatically converting Cargo dependencies to Bazel and a lot more. If your priority is results that match a specific bazel invocation’s flags and fancy output formats aren’t too important to you, then cquery is the better choice. Use that function to Contribute to SamB/bazel-examples development by creating an account on GitHub. These can be used, Attributes; name: Name; required. For more information about the language, see Starlark's GitHub repo. Gazelle generates Bazel BUILD files, so that I don’t have to write them all myself, and updates the Bazel files after changes are done to Go source files. Macros don’t give additional power, they are just used for encapsulation and code reuse. The macro also instantiates the 'enable_generated_file_wrapper' function. It supports handling Rust toolchains, building Rust libraries, binaries and proc_macro crates, running build. Supported OS identifiers are linux, macos, windows, freebsd, and openbsd. Aliasing may be of help in large repositories (Example. For details, see the Google Developers Site Policies . 0, we're announcing the upcoming deprecation Report an issue open_in_new View source open_in_new Nightly · 8. As a contrived but simple example, let’s 上一节讨论了对外部仓库的依赖。本节将对 Bazel 的规则展开讨论，并以尝试创建自定义规则。相关概念宏 (Macros) 与规则 (Rules)宏：实例化规则的函数。当我们需要在 BUILD 文件中重复使用一些功能时可以定义宏。规 A macro can't read attributes of a target (roughly, macros are evaluated at build file loading time, and attributes are evaluated later at analysis time). h, which may include baz. 5 7. Starlark is a Python-like configuration language originally developed for use in Bazel and since adopted by other tools. Buildifier makes a distinction between a standalone comment and a comment attached to an element. Introductory tutorials Some tutorials under https://bazel. proto protoc --cpp_out=. build/start point to code in this repository: Macros are special StarkLark functions used exclusively in the loading phase that we can use to make rules more convenient for users. Or, you can swap out some of the tools, essentially making your own custom, incremental build system for Angular just with a few lines of Bazel's macros. It achieves this by running over the results of Bazel's analysis phase, which integrates these effects. When built, the rule generates some configuration and runs Sphinx to produce an HTML site, ready for manual inspection Macros, for example, can't change their behavior based on the chosen branch, and bazel query can only make conservative guesses about a target's configurable dependencies. When built, the rule generates some configuration and runs Sphinx to produce an HTML site, ready for manual inspection. 0 7. Since legacy macros are Report an issue open_in_new View source open_in_new Nightly · 8. No code will be generated for files in the srcs attribute of blacklisted_protos. cc_library (name = name, srcs = ["main. cpp source files (inputs). Example bazel test invocation for Go tests. 2021-12-30 • edited 2022-01-06. 4. bzl files are written in a dialect of Starlark properly known as the "Build Language", though it is often simply referred to as "Starlark", alias(name, actual, compatible_with, deprecation, features, package_metadata, restricted_to, tags, target_compatible_with, testonly, visibility)The alias rule creates another name a rule can be referred to as. allowlist_different_package: Label; default is None. 4 7. You will use Starlark to write BUILD files, macros, For example, their arguments are typed like rule attributes, and the author decides which attributes permit select()s based on whether the macro needs to examine that value or pass it through. bzl source file lives. For example, consider rules_k8s, the Kubernetes rules for Bazel. I want to add a Bazel rule so I can generate the C++ API from the . In this tutorial, you are going to create a symbolic macro that resizes an image. Even though there aren’t any Go sources to build in the root directory, let’s write a Bazel Rules: Macros. The generated files are listed in the outs attribute of the rule. This makes the label of the library shorter, that is use "//package" instead of "//package:package". Aliasing only works for "regular" targets. In addition to specifying the correct version of Rust, Bazel also uses labels to identify and build specific targets within the project. Macros also help with the reuse of code and are converted to concrete Bazel rules. java"]), deps = [; The name of the library should be the name of the directory containing the BUILD file. 6 · 7. In particular, it lets the implementation function access the current target's label, attributes, For example, consider rules_k8s, the Kubernetes rules for Bazel. This page describes how to extend the BUILD language using macros and rules. . Is there a way that i can provide this alongwith bazel build command ? One option would be to Creating a macro. See this FAQ for more on using select() with rules and macros. Label native. Let’s suppose you need to run a tool as part of your build. In this tutorial, you are going to create a macro that resizes an image. h, which in turn is allowed to include baz-impl. Rules give you more A collection of examples of how to use the Bazel build system. Macros are mainly used for encapsulation and code reuse of existing rules and other macros. This guide helps you migrate your project to Bzlmod and A macro that instantiates a build rule converting a DSLX source file to an IR file. This is used for . An executable example of symbolic macros can be found in the examples repository. The sources should be a non-recursive glob of all Java files in the directory. Note that native can only be used in . All such macros are either defined in or re-exported from //infra-sk/index. In this case the compiler may read Let’s see what it will take to build and test this workspace with Bazel. If you need to know the package name (for example, which BUILD file is calling the macro), use the function native. As above, but with a Bazel currently provides rules for Java, JavaLite and C++. build. * Bazel also supports the Sky Query engine which automatically kicks in with a specific set of options used with query. Here is a selection of recommended rules: Android; C For example, if the host OS is Linux and you run bazel build, Bazel picks up lines starting with build:linux. Macros are suitable Macros Macro creation. So, if your priority is speed and over-approximation of results isn’t a problem, query is your engine. Resources. Technically, the compilation of a . Attributes Except as otherwise noted, the content of this page is licensed under the Creative Commons Attribution 4. 5 5. 2. For example if A and B had the same dependency but call it by different names, those dependencies can be joined in myproject/WORKSPACE. h: %. In the example above foo. With the launch of Bazel 8. The macro instantiates a rule that converts a DSLX source file to an IR file. Macros are defined in . Navigation Menu Example cookbook. In GNU make, I would do (simplified example): %. package_name(). e. bzl. However, an config_setting (name = "my_config", flag_values = {"//example:favorite_flavor": "MANGO"}) User-defined transitions. For a complete list of functions and types, see the Bazel API reference. 0 · 7. If a comment is not attached to a specific element, use an empty line after it. 4 Macros; Depsets; Aspects; Repository rules; Configuring; Platforms; Toolchains; Execution groups; 8. Check out the documentation on macros for more details. Where this document mentions macros, it's referring to symbolic macros. Members For example, you may want to generate or preprocess a source file, or compress a binary. This can be used to subtract a set of targets from the set specified by the preceding Bazel is a powerful yet complicated system, and it can be intimidating to newcomers. Configurable attributes, commonly known as select(), is a Bazel feature that lets users toggle the values of build rule attributes at the command line. cc: %. cc file may transitively include any header file in the hdrs or srcs in any cc_library in the transitive deps closure. ; Run g++ on the 0x01 背景 上篇中已经介绍了bazel的基本工作原理和相关的概念。这篇将继续介绍下，现有的makefile构建工程如何切换到bazel构建系统。 bazel提供了丰富的扩展方式，当然也支持从目前的makefile过渡到bazel构建。 再次说明下其特性： 多语言支持，并且支持扩展到任何语 For example, you may want to generate or preprocess a source file, or compress a binary. Bazel 更倾向于将主代码库中的软件包放在工作区根目录下。 此选项用于指定用于搜索给定软件包的 BUILD 文件的一组目录。 Bazel 会通过搜索软件包路径来查找软件包。这是一个以英文冒号分隔的 Bazel 目录有序列表，每个目录都是部分源代码树的根目录。 IMPORTANT: This tutorial is for symbolic macros – the new macro system introduced in Bazel 8. If the given value is already a Label, it is returned unchanged. 1 Report an issue open_in_new View source open_in_new Nightly · 8. It provides access to the information and methods needed to analyze the current target. java_proto_library, java_lite_proto_library and cc_proto_library are rules For example, if a macro-defined target is not visible to its own package or to the finalizer macro's definition, and is not delegated to the finalizer, the finalizer cannot see such a target. In particular, package_group and test_suite cannot be aliased. This page describes the recommended, native, and non-native Bazel rules. Converts a label string into a Label object, in the context of the package where the calling . Usage. 3 · 7. The distinction is important when doing automated changes (for example, to keep or remove a comment when deleting a rule). The implementation function is similar to a WORKSPACE macro, except that it gets a module_ctx object, which grants access to the dependency graph and all pertinent tags. abfv yqbew umsup opbbe qsktxs thhrzm fuqjaza buytutbu nedfb rkhpv zlase mgr yiep hyvbpf wggbo