refactor: group transformer under dedicated module and features flags…

… for dependencies

cdviz-collector/Cargo.toml

@@ -116,11 +116,15 @@ source_opendal = [
   "dep:handlebars",
   "dep:handlebars_misc_helpers",
   "dep:opendal",
+  "transformer_hbs",
 ]
 
+#! ### Transformers
+transformer_hbs = ["dep:handlebars", "dep:handlebars_misc_helpers"]
+
 #! ### Tools
 tool_ui = ["dep:cliclack", "dep:console", "dep:similar"]
-tool_transform = ["source_opendal", "tool_ui"]
+tool_transform = ["source_opendal", "tool_ui", "transformer_hbs"]
 
 [target.'cfg(all(target_env = "musl", target_pointer_width = "64"))'.dependencies.jemallocator]
 version = "0.5"

cdviz-collector/src/errors.rs

@@ -31,9 +31,9 @@ pub(crate) enum Error {
     Opendal(opendal::Error),
     #[cfg(feature = "source_opendal")]
     GlobPattern(globset::Error),
-    #[cfg(feature = "source_opendal")]
+    #[cfg(feature = "transformer_hbs")]
     HandlebarsRender(handlebars::RenderError),
-    #[cfg(feature = "source_opendal")]
+    #[cfg(feature = "transformer_hbs")]
     HandlebarsTemplate(handlebars::TemplateError),
     #[cfg(feature = "source_opendal")]
     Csv(csv::Error),

cdviz-collector/src/sources/mod.rs

@@ -1,5 +1,4 @@
 pub(crate) mod extractors;
-mod hbs;
 #[cfg(feature = "source_http")]
 pub(crate) mod http;
 #[cfg(feature = "source_opendal")]

cdviz-collector/src/sources/transformers/hbs.rs

@@ -0,0 +1,30 @@
+use crate::errors::Result;
+use crate::pipes::Pipe;
+use crate::sources::{EventSource, EventSourcePipe};
+use handlebars::Handlebars;
+
+pub(crate) struct Processor {
+    next: EventSourcePipe,
+    renderer: Handlebars<'static>,
+}
+
+impl Processor {
+    pub(crate) fn new(template: &str, next: EventSourcePipe) -> Result<Self> {
+        let mut renderer = Handlebars::new();
+        renderer.set_dev_mode(false);
+        renderer.set_strict_mode(true);
+        renderer.register_escape_fn(handlebars::no_escape);
+        handlebars_misc_helpers::register(&mut renderer);
+        renderer.register_template_string("tpl", template)?;
+        Ok(Self { next, renderer })
+    }
+}
+
+impl Pipe for Processor {
+    type Input = EventSource;
+    fn send(&mut self, input: Self::Input) -> Result<()> {
+        let res = self.renderer.render("tpl", &input)?;
+        let output: EventSource = serde_json::from_str(&res)?;
+        self.next.send(output)
+    }
+}

cdviz-collector/src/sources/transformers.rs → cdviz-collector/src/sources/transformers/mod.rs

@@ -1,6 +1,9 @@
+#[cfg(feature = "transformer_hbs")]
+mod hbs;
+
 use std::collections::HashMap;
 
-use super::{hbs, EventSourcePipe};
+use super::EventSourcePipe;
 use crate::{
     errors::{Error, Result},
     pipes::{discard_all, log, passthrough},
@@ -17,6 +20,7 @@ pub(crate) enum Config {
     Log(log::Config),
     #[serde(alias = "discard_all")]
     DiscardAll,
+    #[cfg(feature = "transformer_hbs")]
     #[serde(alias = "hbs")]
     Hbs { template: String },
     // #[serde(alias = "vrl")]
@@ -29,6 +33,7 @@ impl Config {
             Config::Passthrough => Box::new(passthrough::Processor::new(next)),
             Config::Log(config) => Box::new(log::Processor::try_from(config, next)?),
             Config::DiscardAll => Box::new(discard_all::Processor::new()),
+            #[cfg(feature = "transformer_hbs")]
             Config::Hbs { template } => Box::new(hbs::Processor::new(template, next)?),
         };
         Ok(out)