20 releases
0.9.0 | Oct 31, 2024 |
---|---|
0.9.0-alpha.1 | Jul 20, 2022 |
0.8.0 | Dec 14, 2021 |
0.7.1 | Nov 2, 2020 |
0.2.1 | Mar 31, 2020 |
#128 in Parser implementations
13,903 downloads per month
Used in 3 crates
130KB
3.5K
SLoC
dockerfile-parser-rs
A pure Rust library for parsing and inspecting Dockerfiles, useful for performing static analysis, writing linters, and creating automated tooling around Dockerfiles. It uses a proper grammar and can provide useful syntax errors in addition to a full syntax tree.
Limitations
- Buildkit parser directives are not handled at all.
- Unknown instructions are parsed as
MiscInstruction
rather than producing an explicit error. A number of valid but less interesting Docker instructions are handled this way, e.g.ONBUILD
,MAINTAINER
, etc. See notes in the grammar for details.
Usage
See ./examples
for a few usage examples, including a small
utility to dump a Dockerfile's structure:
$ cargo run --example stages Dockerfile.test
Finished dev [unoptimized + debuginfo] target(s) in 0.03s
Running `target/debug/dockerfile Dockerfile.test`
global arg: ArgInstruction { name: "foo", value: None }
stages:
stage #0
From(FromInstruction { image: "foo:443/bar", index: 0, alias: None })
stage #1
From(FromInstruction { image: "localhost/foo", index: 1, alias: None })
stage #2
From(FromInstruction { image: "example.com/foo:bar", index: 2, alias: None })
stage #3
From(FromInstruction { image: "alpine:3.10", index: 3, alias: None })
stage #4
From(FromInstruction { image: "foo/bar", index: 4, alias: None })
stage #5
From(FromInstruction { image: "foo/bar:baz", index: 5, alias: None })
stage #6
From(FromInstruction { image: "hello-world:test", index: 6, alias: Some("foo") })
stage #7
From(FromInstruction { image: "fooasdf", index: 7, alias: Some("bar-baz") })
Run(Exec(["foo", "bar", "echo \"hello $world\""]))
Run(Shell("foo bar baz"))
Arg(ArgInstruction { name: "image", value: Some("alpine:3.10") })
stage #8
From(FromInstruction { image: "$image", index: 8, alias: None })
stage #9
From(FromInstruction { image: "alpine:3.10", index: 9, alias: Some("foo") })
Run(Exec(["foo", "bar"]))
Run(Shell("foo bar baz qux qup"))
Copy(CopyInstruction { flags: [CopyFlag { name: "from", value: "foo" }], sources: ["/foo/bar", "/foo/baz"], destination: "/qux/" })
Entrypoint(Shell("foo bar baz"))
Entrypoint(Exec(["foo", "bar", "baz"]))
Cmd(Shell("foo bar"))
Cmd(Exec(["foo", "bar"]))
Copy(CopyInstruction { flags: [], sources: ["foo"], destination: "bar" })
Copy(CopyInstruction { flags: [CopyFlag { name: "from", value: "0" }], sources: ["/foo"], destination: "/bar" })
Misc(MiscInstruction { instruction: "other", arguments: "foo bar" })
Misc(MiscInstruction { instruction: "other", arguments: "foo bar" })
Env(EnvInstruction([EnvVar { key: "foo", value: "bar baz qux" }]))
Env(EnvInstruction([EnvVar { key: "foo", value: "bar" }, EnvVar { key: "baz", value: "qux" }]))
Env(EnvInstruction([EnvVar { key: "zxcv", value: "asdf" }]))
Env(EnvInstruction([EnvVar { key: "foo", value: "bar zxcv" }, EnvVar { key: "baz", value: "qux" }, EnvVar { key: "zxcv", value: "asdf\"qwerty" }, EnvVar { key: "zxcv", value: "zxcvzxvb" }]))
Label(LabelInstruction([Label { name: "foo", value: "bar" }]))
Label(LabelInstruction([Label { name: "foo", value: "bar" }]))
Label(LabelInstruction([Label { name: "foo bar", value: "baz qux" }]))
Label(LabelInstruction([Label { name: "foo bar", value: "baz\" qux" }]))
Misc(MiscInstruction { instruction: "foo", arguments: "bar" })
Splicing
Some instruction structs also include character spans for various attributes (or the entire instruction). The included splicing utility can be used to rewrite these spans while preserving other user formatting within the file. For example, this can be used to implement a utility that automatically updates image versions, or to provide automated fixes for detected lints.
See examples/splice.rs
for an example that rewrites
image references.
Contributing
Bug reports, feature requests, and pull requests are welcome! Be sure to read though the code of conduct for some pointers to get started.
Note that - as mentioned in the code of conduct - code contributions must
indicate that you accept the Developer Certificate of Origin,
essentially asserting you have the necessary rights to submit the code you're
contributing under the project's license (MIT). If you agree, simply pass -s
to git commit
:
git commit -s [...]
... and Git will automatically append the required Signed-off-by: ...
to the
end of your commit message.
Dependencies
~4.5–6MB
~115K SLoC