Upgrade base64 to 0.21 (#123)

Summary: Pull Request resolved: facebookresearch/Private-ID#123

Reviewed By: zertosh

Differential Revision: D61737689

fbshipit-source-id: dc98887dd6b346f11d8efe7ffa085311f6110c37

unsupported/juno/crates/juno_support/Cargo.toml

@@ -7,7 +7,7 @@ license = "MIT"
 
 [dependencies]
 libcplusplus = { path = "../libcplusplus" }
-base64 = "0.13"
+base64 = "0.21.7"
 anyhow = "1.0"
 thiserror = "1.0"
 url = "2.2.2"

unsupported/juno/crates/juno_support/src/fetchurl.rs

@@ -18,10 +18,21 @@ use std::fs::File;
 use std::io::Read;
 
 use anyhow;
-use base64;
+use base64::alphabet::URL_SAFE;
+use base64::engine::general_purpose::GeneralPurpose;
+use base64::engine::general_purpose::GeneralPurposeConfig;
+use base64::engine::general_purpose::PAD;
+use base64::engine::DecodePaddingMode;
+use base64::Engine;
 use thiserror;
 use url::Url;
 
+// Bring back the pre 0.20 bevahiour and allow either padded or un-padded base64 strings at decode time.
+const URL_SAFE_INDIFFERENT: GeneralPurpose = GeneralPurpose::new(
+    &URL_SAFE,
+    PAD.with_decode_padding_mode(DecodePaddingMode::Indifferent),
+);
+
 #[derive(thiserror::Error, Debug)]
 pub enum FetchError {
     #[error("URL parse error")]
@@ -125,7 +136,7 @@ fn fetch_data(url: &Url) -> Result<Data, FetchError> {
         return Err(FetchError::InvalidURL("data URL unsupported encoding"));
     }
 
-    let buf = base64::decode_config(data, base64::URL_SAFE).map_err(|e| {
+    let buf: Vec<u8> = URL_SAFE_INDIFFERENT.decode(data).map_err(|e| {
         FetchError::DecodeError(anyhow::anyhow!(e).context("error decoding data URL"))
     })?;