feat: add sp-extract for extracting data files from subplots

5 files changed, 87 insertions, 1 deletions

diff --git a/src/bin/sp-extract.rs b/src/bin/sp-extract.rs
new file mode 100644
index 0000000..d63fa0a
--- /dev/null
+++ b/src/bin/sp-extract.rs
@@ -0,0 +1,46 @@
+use anyhow::Result;
+use std::fs::write;
+use std::path::PathBuf;
+
+use structopt::StructOpt;
+
+use subplot::{DataFile, Document, SubplotError};
+
+#[derive(Debug, StructOpt)]
+#[structopt(name = "sp-meta", about = "Show Subplot document metadata.")]
+struct Opt {
+    /// Input subplot document filename
+    #[structopt(parse(from_os_str))]
+    filename: PathBuf,
+
+    /// Names of embedded files to be extracted.
+    #[structopt()]
+    embedded: Vec<String>,
+
+    // Set output directory.
+    #[structopt(name = "DIR", long = "--directory", short = "-o", parse(from_os_str))]
+    directory: PathBuf,
+}
+
+fn main() -> Result<()> {
+    let opt = Opt::from_args();
+    let basedir = subplot::get_basedir_from(&opt.filename)?;
+    let doc = Document::from_file(&basedir, &opt.filename)?;
+
+    for filename in opt.embedded {
+        let file = get_embedded(&doc, &filename)?;
+        let output = opt.directory.join(filename);
+        write(output, file.contents())?;
+    }
+
+    Ok(())
+}
+
+fn get_embedded<'a>(doc: &'a Document, filename: &str) -> Result<&'a DataFile> {
+    for file in doc.files() {
+        if file.filename() == filename {
+            return Ok(file);
+        }
+    }
+    Err(SubplotError::EmbeddedFileNotFound(filename.to_owned()).into())
+}
diff --git a/src/error.rs b/src/error.rs
index f988c86..1f4fcc7 100644
--- a/src/error.rs
+++ b/src/error.rs
@@ -187,6 +187,10 @@ pub enum SubplotError {
     #[error("template.yaml does not specify how to run generated program")]
     TemplateNoRun,
 
+    /// An embedded file was not found.
+    #[error("emedded file {0} was not found in the subplot document")]
+    EmbeddedFileNotFound(String),
+
     /// I/O error
     ///
     /// Subplot did some I/O, and it failed. This is a generic wrapper
diff --git a/subplot.md b/subplot.md
index b2cdecf..e0a31b2 100644
--- a/subplot.md
+++ b/subplot.md
@@ -2093,8 +2093,35 @@ It does not have a YAML metadata block.
 ~~~~~~~~
 
 
+# Extract embedded files
+
+`sp-extract` extracts embedded files from a subplot file.
+
+~~~scenario
+given file embedded-file.md
+and file expected.txt
+when I run sp-extract embedded-file.md foo.txt -d .
+then files foo.txt and expected.txt match
+~~~
+
+~~~~~~{#embedded-file.md .file .markdown .numberLines}
+---
+title: Embedded file
+...
+
+~~~{#foo.txt .file}
+This is a test file.
+~~~
+
+~~~~~~
+
+~~~{#expected.txt .file}
+This is a test file.
+~~~
+
+
+
 
-  
 ---
 title: "Subplot"
 author: The Subplot project
diff --git a/subplot.py b/subplot.py
index fa3d502..1bb42d7 100644
--- a/subplot.py
+++ b/subplot.py
@@ -61,6 +61,12 @@ def run_meta_json(ctx, filename=None):
     exit_code_is(ctx, 0)
 
 
+def run_extract(ctx, filename=None, embedded=None, dirname=None):
+    extract = binary("sp-extract")
+    runcmd(ctx, [extract, filename, embedded, "-o", dirname])
+    exit_code_is(ctx, 0)
+
+
 def run_pandoc_with_filter(ctx, filename=None, output=None):
     sp_filter = binary("sp-filter")
     runcmd(ctx, ["pandoc", "--filter", sp_filter, filename, "-o", output])
diff --git a/subplot.yaml b/subplot.yaml
index 84e52e4..0b63302 100644
--- a/subplot.yaml
+++ b/subplot.yaml
@@ -28,6 +28,9 @@
 - when: I run sp-meta {filename} -o json
   function: run_meta_json
 
+- when: I run sp-extract {filename} {embedded} -d {dirname}
+  function: run_extract
+
 - when: I run pandoc --filter sp-filter {filename} -o {output}
   function: run_pandoc_with_filter