structopt-ify, move list ablum to subcommand add filtering by regex.

src/main.rs

@@ -1,15 +1,44 @@
-use std::path::Path;
+use std::error::Error;
+use std::path::PathBuf;
 
 use google_api_auth;
 use google_photoslibrary1;
-use yup_oauth2::GetToken;
+use regex::Regex;
+use structopt::StructOpt;
 use yup_oauth2::{Authenticator, InstalledFlow};
 
-fn main() -> Result<(), Box<dyn std::error::Error>> {
-    // Read application secret from a file. Sometimes it's easier to compile it directly into
-    // the binary. The clientsecret file contains JSON like `{"installed":{"client_id": ... }}`
-    let credentials = "/home/wathiede/src/xinu.tv/photosync/auth/oob-credentials.json";
-    let secret = yup_oauth2::read_application_secret(Path::new(credentials)).expect(credentials);
+#[derive(Debug, StructOpt)]
+enum Command {
+    /// List albums for the user of the given credentials.  Optionally title filter.
+    ListAlbums { title_filter: Option<Regex> },
+}
+
+#[derive(Debug, StructOpt)]
+#[structopt(
+    name = "photosync",
+    about = "Utility for interacting with Google Photos API."
+)]
+struct Opt {
+    /// Activate debug mode
+    #[structopt(short, parse(from_occurrences))]
+    verbose: u32,
+
+    /// Path to json file containing Google client ID and secrets for out of band auth flow.
+    #[structopt(long)]
+    credentials: PathBuf,
+    /// Path to json file where photosync will store auth tokens refreshed from Google.
+    #[structopt(long)]
+    token_cache: PathBuf,
+
+    #[structopt(subcommand)]
+    cmd: Command,
+}
+
+fn new_client(
+    credentials: &PathBuf,
+    token_cache: &PathBuf,
+) -> Result<google_photoslibrary1::Client, Box<dyn Error>> {
+    let secret = yup_oauth2::read_application_secret(credentials)?;
 
     // Create an authenticator that uses an InstalledFlow to authenticate. The
     // authentication tokens are persisted to a file named tokencache.json. The
@@ -19,7 +48,7 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
         secret,
         yup_oauth2::InstalledFlowReturnMethod::Interactive,
     ))
-    .persist_tokens_to_disk("/tmp/tokencache.json")
+    .persist_tokens_to_disk(token_cache)
     .build()
     .unwrap();
 
@@ -27,18 +56,43 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
 
     let auth = google_api_auth::yup_oauth2::from_authenticator(auth, scopes);
 
-    let client = google_photoslibrary1::Client::new(auth);
+    Ok(google_photoslibrary1::Client::new(auth))
+}
+
+fn list_albums(
+    client: google_photoslibrary1::Client,
+    title_filter: Option<Regex>,
+) -> Result<(), Box<dyn Error>> {
     for album in client
         .shared_albums()
         .list()
         .iter_shared_albums_with_all_fields()
     {
         let a = album?;
+        if let Some(title_filter) = &title_filter {
+            match &a.title {
+                Some(title) => {
+                    if !title_filter.is_match(&title) {
+                        continue;
+                    }
+                }
+                None => continue,
+            }
+        }
         println!(
             "album: {} {}",
             a.id.unwrap_or("NO ID".to_string()),
-            a.title.unwrap_or("NO TITLE".to_string())
+            a.title.unwrap_or("NO TITLE".to_string()).to_string()
         );
     }
     Ok(())
 }
+
+fn main() -> Result<(), Box<dyn std::error::Error>> {
+    let opt = Opt::from_args();
+    println!("opt: {:?}", opt);
+    let client = new_client(&opt.credentials, &opt.token_cache)?;
+    match opt.cmd {
+        Command::ListAlbums { title_filter } => list_albums(client, title_filter),
+    }
+}