From 9a3e40012ac7936a72bdbb705f463553b9ba9c3d Mon Sep 17 00:00:00 2001
From: Ian Jackson <ijackson@chiark.greenend.org.uk>
Date: Tue, 4 May 2021 01:09:12 +0100
Subject: [PATCH] AssetUrlKey: parse and display

Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>
---
 Cargo.lock     |  1 +
 Cargo.toml     |  1 +
 src/bundles.rs | 24 +++++++++++++++++++++++-
 src/imports.rs |  1 +
 4 files changed, 26 insertions(+), 1 deletion(-)

diff --git a/Cargo.lock b/Cargo.lock
index 690f27cb..dda0ee9e 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2188,6 +2188,7 @@ dependencies = [
  "anyhow",
  "argparse",
  "backtrace",
+ "base64 0.13.0",
  "boolinator",
  "bundle-sources",
  "byteorder",
diff --git a/Cargo.toml b/Cargo.toml
index 24c60825..dc43c514 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -31,6 +31,7 @@ otter-base.version="=0.5.1"
 anyhow="1"
 argparse="0.2"
 backtrace="0.3"
+base64="0.13"
 boolinator="2"
 byteorder="1.3"
 cast_trait_object="0.1"
diff --git a/src/bundles.rs b/src/bundles.rs
index 96b49190..4bf8358b 100644
--- a/src/bundles.rs
+++ b/src/bundles.rs
@@ -73,8 +73,9 @@ impl AssetUrlKey {
     AssetUrlKey::Y(buf)
   }
 }
+type AssetUrlTokenRaw = digest::Output<Digester>;
 #[derive(Clone)]
-pub struct AssetUrlToken(digest::Output<Digester>);
+pub struct AssetUrlToken(AssetUrlTokenRaw);
 impl Debug for AssetUrlToken {
   #[throws(fmt::Error)]
   fn fmt(&self, f: &mut Formatter) { write!(f, "AssetUrlToken{{..}}")?; }
@@ -93,6 +94,27 @@ impl AssetUrlKey {
     AssetUrlToken(dw.finish().0)
   }
 }
+impl Display for AssetUrlToken {
+  #[throws(fmt::Error)]
+  fn fmt(&self, f: &mut Formatter) {
+    f.write_str(&base64::encode_config(&self.0, base64::URL_SAFE_NO_PAD))?
+  }
+}
+impl FromStr for AssetUrlToken {
+  type Err = BadAssetUrlToken;
+  #[throws(BadAssetUrlToken)]
+  fn from_str(s: &str) -> Self {
+    let mut buf: AssetUrlTokenRaw = default();
+    let l = base64::decode_config_slice(
+      s.as_bytes(), base64::URL_SAFE_NO_PAD, &mut buf)
+      .map_err(|_| BadAssetUrlToken)?;
+    if l != buf.len() { throw!(BadAssetUrlToken) }
+    AssetUrlToken(buf)
+  }
+}
+#[derive(Error,Debug,Copy,Clone,Serialize)]
+pub struct BadAssetUrlToken;
+display_as_debug!{BadAssetUrlToken}
 
 #[derive(Copy,Clone,Debug,Hash,PartialEq,Eq,Ord,PartialOrd)]
 #[derive(Serialize,Deserialize)]
diff --git a/src/imports.rs b/src/imports.rs
index 00a01274..5608f67f 100644
--- a/src/imports.rs
+++ b/src/imports.rs
@@ -6,6 +6,7 @@ pub use otter_base;
 pub use otter_base::imports::*;
 
 pub use anyhow;
+pub use base64;
 pub use boolinator;
 pub use cast_trait_object;
 pub use chrono;
-- 
2.30.2