Clojure 工具链演进：Leiningen、Clojure CLI 与 deps.edn

(defproject myapp "1.0.0-SNAPSHOT"
  :description "我的 Clojure 应用"
  :url "https://example.com"
  :license {:name "EPL-2.0"
            :url "https://www.eclipse.org/legal/epl-2.0/"}

  ;; 依赖管理（类比 Maven）
  :dependencies [[org.clojure/clojure "1.11.1"]
                 [ring/ring-core "1.10.0"]
                 [compojure "1.7.0"]
                 [org.clojure/java.jdbc "0.7.12"]]

  ;; 开发环境额外依赖
  :profiles {:dev {:dependencies [[org.clojure/tools.namespace "1.4.4"]]
                   :source-paths ["dev"]}
             :uberjar {:aot :all
                       :jvm-opts ["-Dclojure.compiler.direct-linking=true"]}}

  ;; 插件扩展
  :plugins [[lein-ring "0.12.6"]]

  ;; 主入口
  :main ^:skip-aot myapp.core

  ;; 测试配置
  :test-selectors {:default (complement :slow)
                   :slow :slow})

;; deps.edn — 纯数据（EDN），非代码
{:paths ["src" "resources"]

 ;; Maven 依赖
 :deps {org.clojure/clojure {:mvn/version "1.11.1"}
        ring/ring-core {:mvn/version "1.10.0"}
        metosin/reitit {:mvn/version "0.7.0"}}

 ;; 别名（功能模块化）
 :aliases
 {:dev {:extra-paths ["dev"]
        :extra-deps {org.clojure/tools.namespace {:mvn/version "1.4.4"}}}

  :test {:extra-paths ["test"]
         :extra-deps {io.github.cognitect-labs/test-runner
                      {:git/tag "v0.5.1" :git/sha "dfb30dd"}}
         :main-opts ["-m" "cognitect.test-runner"]
         :exec-fn cognitect.test-runner.api/test}

  :build {:deps {io.github.clojure/tools.build {:git/tag "v0.9.6" :git/sha "8e78bcc"}}
          :ns-default build}

  :uber {:replace-deps {com.github.seancorfield/depstar {:mvn/version "2.1.303"}}
         :exec-fn hf.depstar/uberjar
         :exec-args {:aot true
                     :main-class myapp.core
                     :jar "target/myapp.jar"}}}}

# macOS（Homebrew）
brew install clojure/tools/clojure

# Linux（官方安装脚本）
curl -L -O https://github.com/clojure/brew-install/releases/latest/download/linux-install.sh
chmod +x linux-install.sh
sudo ./linux-install.sh

# 验证安装
clojure --version
# => Clojure CLI version 1.11.1.1435

;; build.clj
(ns build
  (:require [clojure.tools.build.api :as b]))

(def lib 'com.example/myapp)
(def version "1.0.0")
(def class-dir "target/classes")
(def basis (b/create-basis {:project "deps.edn"}))
(def uber-file (format "target/%s-%s.jar" (name lib) version))

(defn clean [_]
  (b/delete {:path "target"}))

(defn jar [_]
  (b/write-pom {:class-dir class-dir
                :lib lib
                :version version
                :basis basis
                :src-dirs ["src"]})
  (b/copy-dir {:src-dirs ["src" "resources"]
               :target-dir class-dir})
  (b/jar {:class-dir class-dir
          :jar-file (format "target/%s-%s-lib.jar" (name lib) version)}))

(defn uber [_]
  (clean nil)
  (b/copy-dir {:src-dirs ["src" "resources"]
               :target-dir class-dir})
  (b/compile-clj {:basis basis
                  :src-dirs ["src"]
                  :class-dir class-dir})
  (b/uber {:class-dir class-dir
           :uber-file uber-file
           :basis basis
           :main 'myapp.core}))

# 清理
clojure -T:build clean

# 构建库 JAR
clojure -T:build jar

# 构建可执行 uberjar
clojure -T:build uber

# 运行
java -jar target/myapp-1.0.0.jar

;; .emacs 或 init.el 配置
(require 'cider)

;; 连接 Clojure CLI REPL
(setq cider-clojure-cli-aliases ":dev:test")

;; jack-in 快捷键
;; C-c M-j — 启动 REPL
;; C-c C-e — 求值当前表达式
;; C-c C-k — 加载整个文件
;; C-c C-d C-d — 文档查看

// settings.json
{
  "calva.replConnectSequences": [
    {
      "name": "My Project REPL",
      "projectType": "deps.edn",
      "cljsType": "none",
      "menuSelections": {
        "cljAliases": ["dev", "test"]
      }
    }
  ]
}

;; 1. 启动 REPL 和命名空间
(require '[myapp.core :as core])
(in-ns 'myapp.core)

;; 2. 开发函数原型
(defn calculate [x y]
  (* x y))

;; 3. 测试
(calculate 3 4)  ; => 12

;; 4. 修改后重新加载文件
;; C-c C-k（Emacs）或 Reload 按钮（Calva）

;; 5. 使用 tools.namespace 自动重载
(require '[clojure.tools.namespace.repl :refer [refresh]])
(refresh)

# 构建
clojure -T:build uber

# 部署
scp target/myapp-1.0.0.jar server:/opt/app/
ssh server << 'EOF'
cd /opt/app
java -Xmx2g -jar myapp-1.0.0.jar
EOF

FROM clojure:temurin-17-tools-deps-alpine AS builder
WORKDIR /app
COPY deps.edn build.clj ./
COPY src ./src
COPY resources ./resources
RUN clojure -T:build uber

FROM eclipse-temurin:17-jre-alpine
WORKDIR /app
COPY --from=builder /app/target/*.jar app.jar
EXPOSE 8080
ENTRYPOINT ["java", "-Xmx2g", "-Dclojure.compiler.direct-linking=true", "-jar", "app.jar"]

# 1. 安装 GraalVM
sdk install java 21.0.2-graalce
sdk use java 21.0.2-graalce

# 2. 使用 org.graalvm.buildtools 构建 native image
clojure -T:build native-image

# 3. 结果：秒级启动、低内存占用
./target/myapp    # 启动时间 < 50ms