rework cli interface

README.md

@@ -6,7 +6,7 @@ hashes.
 ## Usage
 
 ```bash
-cargo r -- <app id> --depot <depot id>
+depot-prefetch fetch <app id> --depot <depot id>
 ```
 
 `--depot` can be specified multiple times, or left out to fetch all available
@@ -15,8 +15,13 @@ depots.
 You can find depot id's for an app on
 [steamdb](https://steamdb.info/app/232250/depots/).
 
-If you only care about knowing the latest manifest, you can pass `--dont-fetch`
-to disable pre-fetching the manifest's data.
+If you only care about knowing the latest manifest, you can use
+
+```bash
+depot-prefetch manifest <app id> --depot <depot id>
+```
+
+instead.
 
 ## Output
 

src/main.rs

@@ -1,15 +1,29 @@
+use crate::prefetch::prefetch;
+use crate::product_info::{ProductInfoError, ProductInfoFetcher};
 use clap::Parser;
-use crate::product_info::ProductInfoFetcher;
 use main_error::MainResult;
 use serde::Serialize;
-use crate::prefetch::prefetch;
 
-mod product_info;
 mod error;
 mod prefetch;
+mod product_info;
 
 #[derive(Debug, Parser)]
 struct Args {
+    #[command(subcommand)]
+    command: Command,
+}
+
+#[derive(Debug, Parser)]
+enum Command {
+    /// Get the latest manifest and pre-fetch it
+    Fetch(ProductArgs),
+    /// Get the latest manifest without fetching
+    Manifest(ProductArgs),
+}
+
+#[derive(Debug, Parser)]
+struct ProductArgs {
     /// App to prefetch depots for
     app_id: u32,
     /// Branch to prefetch, defaults to "public"
@@ -18,8 +32,6 @@ struct Args {
     /// Only prefetch the listed depot(s)
     #[clap(long)]
     depot: Vec<u32>,
-    #[clap(long)]
-    dont_fetch: bool,
 }
 
 #[tokio::main]
@@ -27,37 +39,58 @@ async fn main() -> MainResult {
     let args = Args::parse();
 
     let info_fetcher = ProductInfoFetcher::new().await?;
-    let depots = info_fetcher.fetch_depots(args.app_id).await?;
     
-    let manifests = depots.into_iter()
-        .filter(|(depot_id, _)| args.depot.is_empty() || args.depot.contains(depot_id))
-        .flat_map(|(depot_id, depot)| depot.branches.into_iter().map(move |(branch, manifest)| (depot_id, branch, manifest)))
-        .filter(|(_, branch, _)| &args.branch == branch)
-        .map(|(depot_id, _, manifest)| ManifestInput {
-            app_id: args.app_id,
-            depot_id,
-            manifest: manifest.gid,
-        });
-
-    if args.dont_fetch {
-        let inputs = manifests.collect::<Vec<_>>();
-        serde_json::to_writer_pretty(std::io::stdout(), &inputs)?;
-    } else {
-        let outputs = manifests.map(|input| {
+    match args.command {
+        Command::Fetch(args) => {
+            let inputs = get_manifests(&info_fetcher, &args).await?;
+            let outputs = inputs.into_iter()
+                .map(|input| {
                     prefetch(&input).map(|hash| ManifestOutput {
                         app_id: input.app_id,
                         depot_id: input.depot_id,
                         manifest: input.manifest,
                         hash,
                     })
-        }).collect::<Result<Vec<_>, _>>()?;
+                })
+                .collect::<Result<Vec<_>, _>>()?;
 
             serde_json::to_writer_pretty(std::io::stdout(), &outputs)?;
         }
+        Command::Manifest(args) => {
+            let inputs = get_manifests(&info_fetcher, &args).await?;
+            serde_json::to_writer_pretty(std::io::stdout(), &inputs)?;
+        }
+    }
 
     Ok(())
 }
 
+async fn get_manifests(
+    info_fetcher: &ProductInfoFetcher,
+    product_args: &ProductArgs,
+) -> Result<Vec<ManifestInput>, ProductInfoError> {
+    let depots = info_fetcher.fetch_depots(product_args.app_id).await?;
+
+    Ok(depots
+        .into_iter()
+        .filter(|(depot_id, _)| {
+            product_args.depot.is_empty() || product_args.depot.contains(depot_id)
+        })
+        .flat_map(|(depot_id, depot)| {
+            depot
+                .branches
+                .into_iter()
+                .map(move |(branch, manifest)| (depot_id, branch, manifest))
+        })
+        .filter(|(_, branch, _)| &product_args.branch == branch)
+        .map(|(depot_id, _, manifest)| ManifestInput {
+            app_id: product_args.app_id,
+            depot_id,
+            manifest: manifest.gid,
+        })
+        .collect())
+}
+
 #[derive(Debug, Serialize)]
 struct ManifestInput {
     app_id: u32,