Teach filter subcommand to recognize --skip and --take options

CHANGELOG.md

@@ -1,4 +1,5 @@
 ## v0.3.1-dev
+- Teach filter subcommand to recognize --skip and --take options
 - MSRV now rustc 1.61
 - forget a channel's initialization segment when no transmitter is active. This improves behavior when a channel is occasionally used for streams with different codecs.
 - Add INFO logging for channel creation/garbage-collection

src/commands/filter.rs

@@ -1,9 +1,9 @@
-use std::{io, io::prelude::*, pin::Pin};
+use std::{io, io::prelude::*, pin::Pin, time::Duration};
 
 use clap::Args;
 use futures::prelude::*;
 
-use super::stdin_stream;
+use super::{parse_time, stdin_stream};
 use webmetro::{
     chunk::{Chunk, WebmStream},
     error::WebmetroError,
@@ -15,19 +15,31 @@ use webmetro::{
 #[derive(Args, Debug)]
 pub struct FilterArgs {
     /// Slow down output to "real time" speed as determined by the timestamps (useful for streaming static files)
-    #[clap(long, short)]
+    #[clap(long)]
     throttle: bool,
+    /// Skip approximately n seconds of content before uploading or throttling
+    #[clap(long, short, parse(try_from_str = parse_time))]
+    skip: Option<Duration>,
+    /// Stop uploading after approximately n seconds of content
+    #[clap(long, short, parse(try_from_str = parse_time))]
+    take: Option<Duration>,
 }
 
 #[tokio::main]
 pub async fn run(args: FilterArgs) -> Result<(), WebmetroError> {
+    let start_time = args.skip.map_or(0, |s| s.as_millis());
+    let stop_time = args
+        .take
+        .map_or(std::u128::MAX, |t| t.as_millis() + start_time);
+
     let mut timecode_fixer = ChunkTimecodeFixer::new();
     let mut chunk_stream: Pin<Box<dyn Stream<Item = Result<Chunk, WebmetroError>> + Send>> =
         Box::pin(
             stdin_stream()
                 .parse_ebml()
                 .chunk_webm()
-                .map_ok(move |chunk| timecode_fixer.process(chunk)),
+                .map_ok(move |chunk| timecode_fixer.process(chunk))
+                .try_filter(move |chunk| future::ready(chunk.overlaps(start_time, stop_time))),
         );
 
     if args.throttle {