From 3a9b9b34084b993e457498b1b5ddf5f281d23a84 Mon Sep 17 00:00:00 2001
From: damiondoesthings <80198756+damiondoesthings@users.noreply.github.com>
Date: Mon, 12 Dec 2022 07:00:58 +0100
Subject: [PATCH] fix truncating signature on SAS (#1007)

# Description
This fixes the truncation of Azure SAS signatures ending in "=", i.e.
when using non-url-encoded SAS tokens.

# Related Issue(s)
<!---
For example:

- closes #1003
--->
closes #1003

Co-authored-by: Damion Werner <damion.werner@arisense.live>
---
 python/tests/test_fs.py   | 18 ++++++++++++++++++
 rust/src/builder/azure.rs | 15 ++++-----------
 2 files changed, 22 insertions(+), 11 deletions(-)

diff --git a/python/tests/test_fs.py b/python/tests/test_fs.py
index 4113b9a2a6..62cdcb8b01 100644
--- a/python/tests/test_fs.py
+++ b/python/tests/test_fs.py
@@ -1,3 +1,5 @@
+import urllib
+
 import pyarrow as pa
 import pyarrow.parquet as pq
 import pytest
@@ -204,3 +206,19 @@ def test_roundtrip_azure_sas(azurite_sas_creds, sample_data: pa.Table):
     table = dt.to_pyarrow_table()
     assert table == sample_data
     assert dt.version() == 0
+
+
+@pytest.mark.azure
+@pytest.mark.integration
+@pytest.mark.timeout(timeout=5, method="thread")
+def test_roundtrip_azure_decoded_sas(azurite_sas_creds, sample_data: pa.Table):
+    table_path = "az://deltars/roundtrip4"
+    azurite_sas_creds["SAS_TOKEN"] = urllib.parse.unquote(
+        azurite_sas_creds["SAS_TOKEN"]
+    )
+
+    write_deltalake(table_path, sample_data, storage_options=azurite_sas_creds)
+    dt = DeltaTable(table_path, storage_options=azurite_sas_creds)
+    table = dt.to_pyarrow_table()
+    assert table == sample_data
+    assert dt.version() == 0
diff --git a/rust/src/builder/azure.rs b/rust/src/builder/azure.rs
index 07753fbe6b..448f8379ad 100644
--- a/rust/src/builder/azure.rs
+++ b/rust/src/builder/azure.rs
@@ -226,17 +226,10 @@ fn split_sas(sas: &str) -> Result<Vec<(String, String)>, BuilderError> {
         .filter(|s| !s.chars().all(char::is_whitespace));
     let mut pairs = Vec::new();
     for kv_pair_str in kv_str_pairs {
-        let mut kv = kv_pair_str.trim().split('=');
-        let k = match kv.next().filter(|k| !k.chars().all(char::is_whitespace)) {
-            None => {
-                return Err(BuilderError::MissingCredential);
-            }
-            Some(k) => k,
-        };
-        let v = match kv.next().filter(|k| !k.chars().all(char::is_whitespace)) {
-            None => return Err(BuilderError::MissingCredential),
-            Some(v) => v,
-        };
+        let (k, v) = kv_pair_str
+            .trim()
+            .split_once('=')
+            .ok_or(BuilderError::MissingCredential)?;
         pairs.push((k.into(), v.into()))
     }
     Ok(pairs)