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zlayer_builder/
lib.rs

1//! `ZLayer` Builder - Dockerfile parsing, `ZImagefile` support, and buildah command generation
2//!
3//! This crate provides functionality for parsing Dockerfiles (and `ZImagefiles`),
4//! converting them into buildah commands for container image building. It is
5//! designed to be used as part of the `ZLayer` container orchestration platform.
6//!
7//! # Architecture
8//!
9//! The crate is organized into several modules:
10//!
11//! - [`dockerfile`]: Types and parsing for Dockerfile content
12//! - [`buildah`]: Command generation and execution for buildah
13//! - [`builder`]: High-level [`ImageBuilder`] API for orchestrating builds
14//! - [`zimage`]: `ZImagefile` (YAML-based) parsing and Dockerfile conversion
15//! - [`tui`]: Terminal UI for build progress visualization
16//! - [`templates`]: Runtime templates for common development environments
17//! - [`error`]: Error types for the builder subsystem
18//!
19//! # Quick Start with `ImageBuilder`
20//!
21//! The recommended way to build images is using the [`ImageBuilder`] API:
22//!
23//! ```no_run
24//! use zlayer_builder::{ImageBuilder, Runtime};
25//!
26//! #[tokio::main]
27//! async fn main() -> Result<(), Box<dyn std::error::Error>> {
28//!     // Build from a Dockerfile
29//!     let image = ImageBuilder::new("./my-app").await?
30//!         .tag("myapp:latest")
31//!         .tag("myapp:v1.0.0")
32//!         .build()
33//!         .await?;
34//!
35//!     println!("Built image: {}", image.image_id);
36//!     Ok(())
37//! }
38//! ```
39//!
40//! # Using Runtime Templates
41//!
42//! Build images without writing a Dockerfile using runtime templates:
43//!
44//! ```no_run
45//! use zlayer_builder::{ImageBuilder, Runtime};
46//!
47//! #[tokio::main]
48//! async fn main() -> Result<(), Box<dyn std::error::Error>> {
49//!     // Auto-detect runtime from project files, or specify explicitly
50//!     let image = ImageBuilder::new("./my-node-app").await?
51//!         .runtime(Runtime::Node20)
52//!         .tag("myapp:latest")
53//!         .build()
54//!         .await?;
55//!
56//!     Ok(())
57//! }
58//! ```
59//!
60//! # Building from a `ZImagefile`
61//!
62//! `ZImagefiles` are a YAML-based alternative to Dockerfiles. The builder
63//! auto-detects a file named `ZImagefile` in the context directory, or you
64//! can point to one explicitly with [`ImageBuilder::zimagefile`]:
65//!
66//! ```no_run
67//! use zlayer_builder::ImageBuilder;
68//!
69//! #[tokio::main]
70//! async fn main() -> Result<(), Box<dyn std::error::Error>> {
71//!     let image = ImageBuilder::new("./my-app").await?
72//!         .zimagefile("./my-app/ZImagefile")
73//!         .tag("myapp:latest")
74//!         .build()
75//!         .await?;
76//!
77//!     Ok(())
78//! }
79//! ```
80//!
81//! `ZImagefiles` support four build modes: runtime template shorthand,
82//! single-stage (`base` + `steps`), multi-stage (`stages` map), and WASM.
83//! See the [`zimage`] module for the full type definitions.
84//!
85//! # Low-Level API
86//!
87//! For more control, you can use the low-level Dockerfile parsing and
88//! buildah command generation APIs directly:
89//!
90//! ```no_run
91//! use zlayer_builder::{Dockerfile, BuildahCommand, BuildahExecutor};
92//!
93//! # async fn example() -> Result<(), zlayer_builder::BuildError> {
94//! // Parse a Dockerfile
95//! let dockerfile = Dockerfile::parse(r#"
96//!     FROM alpine:3.18
97//!     RUN apk add --no-cache curl
98//!     COPY . /app
99//!     WORKDIR /app
100//!     CMD ["./app"]
101//! "#)?;
102//!
103//! // Get the final stage
104//! let stage = dockerfile.final_stage().unwrap();
105//!
106//! // Create buildah commands for each instruction
107//! let executor = BuildahExecutor::new()?;
108//!
109//! // Create a working container from the base image
110//! let from_cmd = BuildahCommand::from_image(&stage.base_image.to_string_ref());
111//! let output = executor.execute_checked(&from_cmd).await?;
112//! let container_id = output.stdout.trim();
113//!
114//! // Execute each instruction
115//! for instruction in &stage.instructions {
116//!     let cmds = BuildahCommand::from_instruction(container_id, instruction);
117//!     for cmd in cmds {
118//!         executor.execute_checked(&cmd).await?;
119//!     }
120//! }
121//!
122//! // Commit the container to create an image
123//! let commit_cmd = BuildahCommand::commit(container_id, "myimage:latest");
124//! executor.execute_checked(&commit_cmd).await?;
125//!
126//! // Clean up the working container
127//! let rm_cmd = BuildahCommand::rm(container_id);
128//! executor.execute(&rm_cmd).await?;
129//!
130//! # Ok(())
131//! # }
132//! ```
133//!
134//! # Features
135//!
136//! ## `ImageBuilder` (High-Level API)
137//!
138//! The [`ImageBuilder`] provides a fluent API for:
139//!
140//! - Building from Dockerfiles or runtime templates
141//! - Multi-stage builds with target stage selection
142//! - Build arguments (ARG values)
143//! - Image tagging and registry pushing
144//! - TUI progress updates via event channels
145//!
146//! ## Dockerfile Parsing
147//!
148//! The crate supports parsing standard Dockerfiles with:
149//!
150//! - Multi-stage builds with named stages
151//! - All standard Dockerfile instructions (FROM, RUN, COPY, ADD, ENV, etc.)
152//! - ARG/ENV variable expansion with default values
153//! - Global ARGs (before first FROM)
154//!
155//! ## Buildah Integration
156//!
157//! Commands are generated for buildah, a daemon-less container builder:
158//!
159//! - Container creation from images or scratch
160//! - Running commands (shell and exec form)
161//! - Copying files (including from other stages)
162//! - Configuration (env, workdir, entrypoint, cmd, labels, etc.)
163//! - Committing containers to images
164//! - Image tagging and pushing
165//!
166//! ## Runtime Templates
167//!
168//! Pre-built templates for common development environments:
169//!
170//! - Node.js 20/22 (Alpine-based, production optimized)
171//! - Python 3.12/3.13 (Slim Debian-based)
172//! - Rust (Static musl binary)
173//! - Go (Static binary)
174//! - Deno and Bun
175//!
176//! ## Variable Expansion
177//!
178//! Full support for Dockerfile variable syntax:
179//!
180//! - `$VAR` and `${VAR}` - Simple variable reference
181//! - `${VAR:-default}` - Default if unset or empty
182//! - `${VAR:+alternate}` - Alternate if set and non-empty
183//! - `${VAR-default}` - Default only if unset
184//! - `${VAR+alternate}` - Alternate if set (including empty)
185
186pub mod backend;
187pub mod buildah;
188pub mod builder;
189pub mod dockerfile;
190pub mod error;
191#[cfg(target_os = "macos")]
192pub mod macos_compat;
193#[cfg(target_os = "macos")]
194pub mod macos_image_resolver;
195#[cfg(target_os = "macos")]
196pub mod macos_toolchain;
197pub mod pipeline;
198#[cfg(target_os = "macos")]
199pub mod sandbox_builder;
200pub mod templates;
201pub mod tui;
202pub mod wasm_builder;
203pub mod zimage;
204
205// Re-export main types at crate root
206pub use buildah::{
207    current_platform,
208    install_instructions,
209    is_platform_supported,
210    BuildahCommand,
211    BuildahExecutor,
212    // Installation types
213    BuildahInstallation,
214    BuildahInstaller,
215    CommandOutput,
216    InstallError,
217};
218#[cfg(feature = "cache")]
219pub use builder::CacheBackendConfig;
220pub use builder::{
221    BuildOptions, BuildOutput, BuiltImage, ImageBuilder, PullBaseMode, RegistryAuth,
222};
223pub use dockerfile::{
224    expand_variables,
225    // Instruction types
226    AddInstruction,
227    ArgInstruction,
228    CopyInstruction,
229    Dockerfile,
230    EnvInstruction,
231    ExposeInstruction,
232    ExposeProtocol,
233    HealthcheckInstruction,
234    ImageRef,
235    Instruction,
236    RunInstruction,
237    ShellOrExec,
238    Stage,
239    // Variable expansion
240    VariableContext,
241};
242pub use error::{BuildError, Result};
243pub use templates::{
244    detect_runtime, detect_runtime_with_version, get_template, get_template_by_name,
245    list_templates, resolve_runtime, Runtime, RuntimeInfo,
246};
247pub use tui::{BuildEvent, BuildTui, InstructionStatus, PlainLogger};
248
249// macOS sandbox builder re-exports
250#[cfg(target_os = "macos")]
251pub use sandbox_builder::{SandboxBuildResult, SandboxImageBuilder, SandboxImageConfig};
252
253// Pipeline re-exports
254pub use pipeline::{
255    parse_pipeline, PipelineCacheConfig, PipelineDefaults, PipelineExecutor, PipelineImage,
256    PipelineResult, PushConfig, ZPipeline,
257};
258
259// Backend re-exports
260#[cfg(target_os = "macos")]
261pub use backend::SandboxBackend;
262pub use backend::{detect_backend, BuildBackend, BuildahBackend};
263
264#[cfg(test)]
265mod tests {
266    use super::*;
267
268    #[test]
269    fn test_parse_and_convert_simple() {
270        let dockerfile = Dockerfile::parse(
271            r#"
272FROM alpine:3.18
273RUN echo "hello"
274COPY . /app
275WORKDIR /app
276"#,
277        )
278        .unwrap();
279
280        assert_eq!(dockerfile.stages.len(), 1);
281
282        let stage = &dockerfile.stages[0];
283        assert_eq!(stage.instructions.len(), 3);
284
285        // Convert each instruction to buildah commands
286        let container = "test-container";
287        for instruction in &stage.instructions {
288            let cmds = BuildahCommand::from_instruction(container, instruction);
289            assert!(!cmds.is_empty() || matches!(instruction, Instruction::Arg(_)));
290        }
291    }
292
293    #[test]
294    fn test_parse_multistage_and_convert() {
295        let dockerfile = Dockerfile::parse(
296            r#"
297FROM golang:1.21 AS builder
298WORKDIR /src
299COPY . .
300RUN go build -o /app
301
302FROM alpine:3.18
303COPY --from=builder /app /app
304ENTRYPOINT ["/app"]
305"#,
306        )
307        .unwrap();
308
309        assert_eq!(dockerfile.stages.len(), 2);
310
311        // First stage (builder)
312        let builder = &dockerfile.stages[0];
313        assert_eq!(builder.name, Some("builder".to_string()));
314        assert_eq!(builder.instructions.len(), 3);
315
316        // Second stage (runtime)
317        let runtime = &dockerfile.stages[1];
318        assert!(runtime.name.is_none());
319        assert_eq!(runtime.instructions.len(), 2);
320
321        // Check COPY --from=builder is preserved
322        if let Instruction::Copy(copy) = &runtime.instructions[0] {
323            assert_eq!(copy.from, Some("builder".to_string()));
324        } else {
325            panic!("Expected COPY instruction");
326        }
327    }
328
329    #[test]
330    fn test_variable_expansion() {
331        let mut ctx = VariableContext::new();
332        ctx.add_arg("VERSION", Some("1.0".to_string()));
333        ctx.set_env("HOME", "/app".to_string());
334
335        assert_eq!(ctx.expand("$VERSION"), "1.0");
336        assert_eq!(ctx.expand("$HOME"), "/app");
337        assert_eq!(ctx.expand("${UNSET:-default}"), "default");
338    }
339
340    #[test]
341    fn test_buildah_command_generation() {
342        // Test various instruction conversions
343        let container = "test";
344
345        // RUN
346        let run = Instruction::Run(RunInstruction {
347            command: ShellOrExec::Shell("apt-get update".to_string()),
348            mounts: vec![],
349            network: None,
350            security: None,
351        });
352        let cmds = BuildahCommand::from_instruction(container, &run);
353        assert_eq!(cmds.len(), 1);
354        assert!(cmds[0].args.contains(&"run".to_string()));
355
356        // ENV
357        let mut vars = std::collections::HashMap::new();
358        vars.insert("PATH".to_string(), "/usr/local/bin".to_string());
359        let env = Instruction::Env(EnvInstruction { vars });
360        let cmds = BuildahCommand::from_instruction(container, &env);
361        assert_eq!(cmds.len(), 1);
362        assert!(cmds[0].args.contains(&"config".to_string()));
363        assert!(cmds[0].args.contains(&"--env".to_string()));
364
365        // WORKDIR
366        let workdir = Instruction::Workdir("/app".to_string());
367        let cmds = BuildahCommand::from_instruction(container, &workdir);
368        assert_eq!(cmds.len(), 1);
369        assert!(cmds[0].args.contains(&"--workingdir".to_string()));
370    }
371}