feat: Add minify_js to decrease file sizes (#210)

This PR uses `minify_js` to minify rendered js files before writing.
This should reduce file sizes slightly.
I probably haven't caught all places js files are written, feel free to
add any that I missed ;)

(It may also be interesting to minify the html files, haven't looked
into that, yet)

Co-authored-by: Felix Wiegand <fxwiegand@wgdnet.de>

Cargo.toml

@@ -26,6 +26,7 @@ lazy_static = "1.4.0"
 regex = "1.6.0"
 log = "0.4.17"
 simplelog = "0.12.0"
+minify-js = "0.2.4"
 
 [dev-dependencies]
 dir-assert = "0.2.0"

src/render/portable/mod.rs

@@ -3,6 +3,7 @@ pub(crate) mod utils;
 
 use crate::render::portable::plot::get_min_max;
 use crate::render::portable::plot::render_plots;
+use crate::render::portable::utils::minify_js;
 use crate::render::Renderer;
 use crate::spec::{
     CustomPlot, DatasetSpecs, HeaderSpecs, Heatmap, ItemSpecs, ItemsSpec, LinkSpec,
@@ -533,8 +534,9 @@ fn render_table_javascript<P: AsRef<Path>>(
 
     let js = templates.render("table.js.tera", &context)?;
 
-    let mut file = fs::File::create(file_path)?;
-    file.write_all(js.as_bytes())?;
+    let mut file = File::create(file_path)?;
+    let minified = minify_js(&js)?;
+    file.write_all(&minified)?;
 
     Ok(())
 }

src/render/portable/plot.rs

@@ -1,3 +1,4 @@
+use crate::render::portable::utils::minify_js;
 use crate::utils::column_type::{classify_table, ColumnType};
 use anyhow::{Context as AnyhowContext, Result};
 use csv::Reader;
@@ -58,7 +59,8 @@ pub(crate) fn render_plots<P: AsRef<Path>>(
         let js = templates.render("plot.js.tera", &context)?;
         let file_path = path.join(Path::new(&format!("plot_{}", index)).with_extension("js"));
         let mut file = fs::File::create(file_path)?;
-        file.write_all(js.as_bytes())?;
+        let minified = minify_js(&js)?;
+        file.write_all(&minified)?;
     }
     Ok(())
 }

src/render/portable/utils.rs

@@ -1,5 +1,6 @@
 use crate::spec::ItemsSpec;
 use anyhow::Result;
+use minify_js::{minify, TopLevelMode};
 use std::fs;
 use std::fs::File;
 use std::io::Write;
@@ -78,6 +79,17 @@ pub(crate) fn render_static_files<P: AsRef<Path>>(path: P) -> Result<()> {
     Ok(())
 }
 
+pub(crate) fn minify_js(file: &str) -> Result<Vec<u8>> {
+    let mut minified: Vec<u8> = Vec::new();
+    minify(
+        TopLevelMode::Global,
+        file.as_bytes().to_vec(),
+        &mut minified,
+    )
+    .expect("Failed minifying js");
+    Ok(minified)
+}
+
 pub(crate) fn render_index_file<P: AsRef<Path>>(path: P, specs: &ItemsSpec) -> Result<()> {
     let table = if let Some(default_view) = &specs.default_view {
         default_view