前语
依据官网的界说，Bazel是类似于Make，Maven和Gradle的开源构建和测试东西。它运用人类可读的高级构建语言Starlark(一种根据python的方言)。 Bazel支撑多种语言的项目，并为多种渠道构建输出。
从我个人视点来看，bazel是一个强壮且复杂的构建系统，经过build rule的概念，支撑多种语言、不同渠道，支撑构建C/C++,Java,Android,IOS,Golang,Nodejs,Docker项目
本文的目的是运用bazel去构建并运转一个spring boot项目。
装备bazel编译java项目
在项目根目录中创立.bazelrc文件，设置bazel运用java17构建：
build --java_language_version=17 --java_runtime_version=17 --tool_java_language_version=17 --tool_java_runtime_version=17
test --java_language_version=17 --java_runtime_version=17 --tool_java_language_version=17 --tool_java_runtime_version=17
在根目录中创立workspace文件，并引进相关的java依靠：
load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")
RULES_JVM_EXTERNAL_TAG = "6.0"
RULES_JVM_EXTERNAL_SHA = "c44568854d8bb92fe0f7dd6b1e8957ae65e45e32a058727fcf62aaafbd36f17b"
http_archive(
name = "rules_jvm_external",
strip_prefix = "rules_jvm_external-%s" % RULES_JVM_EXTERNAL_TAG,
sha256 = RULES_JVM_EXTERNAL_SHA,
urls = [
"https://github.com/bazelbuild/rules_jvm_external/archive/%s.zip" % RULES_JVM_EXTERNAL_TAG,
"https://mirror.ghproxy.com/https://github.com/bazelbuild/rules_jvm_external/archive/%s.zip" % RULES_JVM_EXTERNAL_TAG,
]
)
load("@rules_jvm_external//:repositories.bzl", "rules_jvm_external_deps")
rules_jvm_external_deps()
load("@rules_jvm_external//:setup.bzl", "rules_jvm_external_setup")
# rules_jvm_external_setup()
load("@rules_jvm_external//:specs.bzl", "maven")
load("@rules_jvm_external//:defs.bzl", "maven_install")
然后运用运用maven_install导入spring boot项目的相关依靠。
这儿的shiro依靠被我独自拎出来做特别处理去兼容java17
shiros = [
maven.artifact(
group = "org.apache.shiro",
artifact = "shiro-spring",
version = "1.13.0",
classifier = "jakarta",
exclusions = [
maven.exclusion(
group = "org.apache.shiro",
artifact = "shiro-core",
),
maven.exclusion(
group = "org.apache.shiro",
artifact = "shiro-web",
),
]
),
maven.artifact(
group = "org.apache.shiro",
artifact = "shiro-core",
version = "1.13.0",
classifier = "jakarta",
),
maven.artifact(
group = "org.apache.shiro",
artifact = "shiro-web",
version = "1.13.0",
classifier = "jakarta",
),
]
maven_install(
artifacts = [
"org.springframework.boot:spring-boot:3.2.2",
"org.springframework.boot:spring-boot-starter:3.2.2",
"org.springframework.boot:spring-boot-loader-tools:3.2.2",
"org.springframework.boot:spring-boot-loader:3.2.2",
"org.springframework.boot:spring-boot-starter:3.2.2",
"org.springframework.boot:spring-boot-starter-web:3.2.2",
"org.springframework.boot:spring-boot-starter-jdbc:3.2.2",
"org.springframework.boot:spring-boot-starter-quartz:3.2.2",
"org.springframework.boot:spring-boot-starter-aop:3.2.2",
#"org.springframework.boot:spring-boot-configuration-processor:3.2.2",
"io.springfox:springfox-boot-starter:3.0.0",
"com.auth0:java-jwt:3.19.4",
"org.postgresql:postgresql:42.4.0",
"jakarta.servlet:jakarta.servlet-api:6.0.0",
'javax.annotation:javax.annotation-api:1.3.2',
"org.springframework.boot:spring-boot-devtools:3.2.2",
"org.springframework.boot:spring-boot-starter-test:3.2.2"
] + shiros,
fetch_sources = True,
repositories = [
"https://maven.aliyun.com/repository/public/",
"https://maven.aliyun.com/nexus/content/groups/public/",
"http://uk.maven.org/maven2",
"https://maven.google.com",
"https://repo1.maven.org/maven2",
],
# maven_install_json = "//:maven_install.json",
)
maven_install_json = "//:maven_install.json"现在是被注视掉的，这是因为咱们需求主动生成改文件：
bazel run @maven//:pin
履行成功之后需求在workspace中给maven_install增加maven_install_json特点, 并将加载@maven//:defs.bzl中的pinned_maven_install装备
maven_install(
artifacts = # ...,
repositories = # ...,
maven_install_json = "@//:maven_install.json",
)
load("@maven//:defs.bzl", "pinned_maven_install")
pinned_maven_install()
在更新maven依靠的话，那么能够运用下面的依靠更新maven_install.json
bazel run @unpinned_maven//:pin
maven_install_json是能够不必装备的，可是我引荐尽量装备。它有两个优点，可重复性和速度（reproducibility and speed）。
在根目录创立BUILD.bazel进行编译java项目的预备：
oad("@rules_java//java:defs.bzl", "java_binary", "java_library", "java_test")
package(default_visibility = ["//visibility:public"])
java_library(
name = "jobs-lib",
srcs = glob([
"src/main/java/org/daming/jobs/*.java",
"src/main/java/org/daming/jobs/api/advice/*.java",
"src/main/java/org/daming/jobs/api/controller/*.java",
"src/main/java/org/daming/jobs/api/interceptor/*.java",
"src/main/java/org/daming/jobs/base/*.java",
"src/main/java/org/daming/jobs/base/**/*.java",
"src/main/java/org/daming/jobs/config/**/*.java",
"src/main/java/org/daming/jobs/pojo/**/*.java",
"src/main/java/org/daming/jobs/security/**/*.java",
"src/main/java/org/daming/jobs/service/**/*.java",
"src/main/java/org/daming/jobs/task/**/*.java",
]),
resources = glob(["src/main/resources/**"]),
deps = [
"@maven//:org_springframework_boot_spring_boot_starter_web",
"@maven//:org_springframework_boot_spring_boot_starter_jdbc",
"@maven//:org_springframework_boot_spring_boot_starter_quartz",
"@maven//:org_springframework_boot_spring_boot_starter_aop",
"@maven//:io_springfox_springfox_boot_starter",
"@maven//:io_springfox_springfox_core",
"@maven//:io_springfox_springfox_spi",
"@maven//:io_springfox_springfox_oas",
"@maven//:io_springfox_springfox_spring_web",
"@maven//:io_swagger_swagger_annotations",
"@maven//:com_auth0_java_jwt",
"@maven//:org_postgresql_postgresql",
"@maven//:org_springframework_boot_spring_boot_devtools",
"@maven//:org_springframework_boot_spring_boot",
"@maven//:org_springframework_boot_spring_boot_loader",
"@maven//:org_springframework_boot_spring_boot_loader_tools",
"@maven//:org_springframework_boot_spring_boot_autoconfigure",
"@maven//:org_springframework_spring_aop",
"@maven//:org_springframework_spring_beans",
"@maven//:org_springframework_spring_core",
"@maven//:org_springframework_spring_context",
"@maven//:org_springframework_spring_expression",
"@maven//:org_springframework_spring_web",
# "@maven//:org_apache_shiro_shiro_spring_boot_starter",
"@maven//:org_apache_shiro_shiro_core_jakarta",
"@maven//:org_apache_shiro_shiro_spring_jakarta",
"@maven//:org_apache_shiro_shiro_web_jakarta",
"@maven//:org_slf4j_slf4j_api",
"@maven//:org_quartz_scheduler_quartz",
"@maven//:org_aspectj_aspectjweaver",
"@maven//:org_apache_tomcat_embed_tomcat_embed_core",
"@maven//:jakarta_servlet_jakarta_servlet_api",
"@maven//:jakarta_annotation_jakarta_annotation_api",
"@maven//:jakarta_xml_bind_jakarta_xml_bind_api",
"@maven//:com_fasterxml_jackson_core_jackson_core",
"@maven//:com_fasterxml_jackson_core_jackson_databind"
],
)
java_binary(
name = "jobs",
main_class = "org.daming.jobs.JobsApplication",
runtime_deps = [":jobs-lib"],
deploy_manifest_lines = {
"Main-Class": "org.daming.jobs.JobsApplication",
},
)
然后咱们能够履行bazel命令去构建一个java项目了:
# 构建
bazel build //:jobs
# 构建并运转
bazel run //:jobs
然后你会发现构建没有问题，可是运转会报错:
jobs git:(master) ✗ java -jar bazel-bin/jobs.jar
no main manifest attribute, in bazel-bin/jobs.jar
因为Springboot的代码需求运用Springboot loader进行发动，Springboot程序的打包逻辑与普通的Java程序不同。这意味着，Bazel原生的 java_binary 无法正常发动Springboot程序。
所以咱们需求给bazel装备spring相关支撑。
装备rule_spring去构建运转spring boot
咱们运用salesforce的rules_spring界说好了的rule去协助咱们构建spring boot项目。
咱们在workspace增加rules_spring的规矩文件
http_archive(
name = "rules_spring",
sha256 = "7bb891ccb2f53ca188a769b3a3777be1c38348e18091afea05320f3003b3e886",
urls = [
"https://github.com/salesforce/rules_spring/releases/download/2.3.1/rules-spring-2.3.1.zip",
"https://mirror.ghproxy.com/https://github.com/salesforce/rules_spring/releases/download/2.3.1/rules-spring-2.3.1.zip",
],
)
然后在BUILD.bazel中间中导入rules_spring的相关规矩：
load("@rules_spring//springboot:springboot.bzl", "springboot")
springboot(
name = "springboot",
# specify the main class
boot_app_class = "org.daming.jobs.JobsApplication",
# refrence the library
java_library = ":jobs-lib",
# https://github.com/salesforce/rules_spring/issues/177
boot_launcher_class = 'org.springframework.boot.loader.launch.JarLauncher',
)
因为spring boot 3.2.0之后运用新的发动器，所以咱们这儿指定了boot_launcher_class。 假如你运用的版本低于3.2.0，能够直接删去。
现在咱们能够编译运转spring boot项目了
# 构建
bazel build //:springboot
# 运转
bazel run //:springboot
运转部分输出如下：
Application Name:
Application Version:
Spring Boot Version: 3.2.2 (v3.2.2)
2024-02-11 21:49:17.449 INFO [main] org.springframework.boot.StartupInfoLogger:50 Starting JobsApplication using Java 17 with PID 67028 (/private/var/tmp/_bazel_gming001/7a71463ee80a3358d2f71ab2db616aea/execroot/__main__/bazel-out/darwin_arm64-fastbuild/bin/springboot.jar started by gming001 in /private/var/tmp/_bazel_gming001/7a71463ee80a3358d2f71ab2db616aea/execroot/__main__/bazel-out/darwin_arm64-fastbuild/bin/springboot.runfiles/__main__)
2024-02-11 21:49:17.451 INFO [main] org.springframework.boot.SpringApplication:654 No active profile set, falling back to 1 default profile: "default"
2024-02-11 21:49:17.501 INFO [main] org.springframework.boot.logging.DeferredLog:252 For additional web related logging consider setting the 'logging.level.web' property to 'DEBUG'
2024-02-11 21:49:17.846 WARN [main] org.springframework.context.support.AbstractApplicationContext:632 Exception encountered during context initialization - cancelling refresh attempt: java.lang.TypeNotPresentException: Type javax.servlet.http.HttpServletRequest not present
2024-02-11 21:49:17.856 INFO [main] org.springframework.boot.autoconfigure.logging.ConditionEvaluationReportLogger:82
遗留的问题
有两个问题没有解决，第一个是怎么运转的单元测试，这个还没研究，不过这个不急。还有一个是这个项目实际上跑不起来，会报错：
java.lang.TypeNotPresentException: Type javax.servlet.http.HttpServletRequest not present
我本来以为是bazel的装备问题，成果我发现直接maven也跑不起来。。。
我想了想了应该是springfox没有去适配spring boot3的问题，不想降级spring boot的版本话，只能从springfox迁移到springdoc
源码
本文运用的源代码都能够在jobs看到。
