From d0c079d70c180f7eb1a4d67342430ff2ecdcc29c Mon Sep 17 00:00:00 2001
From: Nadav Ivgi <nadav@shesek.info>
Date: Fri, 5 Apr 2024 18:53:13 +0300
Subject: [PATCH] Add ELECTRUMD_SKIP_DOWNLOAD option

Context: https://github.com/Blockstream/electrs/pull/73
---
 build.rs   |  4 ++--
 src/lib.rs | 15 +++++++++++----
 2 files changed, 13 insertions(+), 6 deletions(-)

diff --git a/build.rs b/build.rs
index db9ee86..f6d750c 100644
--- a/build.rs
+++ b/build.rs
@@ -1,9 +1,9 @@
 use bitcoin_hashes::{sha256, Hash};
 use std::fs;
 use std::io::Read;
+use std::os::unix::fs::PermissionsExt;
 use std::path::Path;
 use std::str::FromStr;
-use std::os::unix::fs::PermissionsExt;
 
 include!("src/versions.rs");
 
@@ -21,7 +21,7 @@ fn get_expected_sha256() -> Result<sha256::Hash, ()> {
 }
 
 fn main() {
-    if !HAS_FEATURE {
+    if !HAS_FEATURE || std::env::var_os("ELECTRUMD_SKIP_DOWNLOAD").is_some() {
         return;
     }
     let download_filename = download_filename();
diff --git a/src/lib.rs b/src/lib.rs
index 8f1427f..0dd21eb 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -68,6 +68,8 @@ pub enum Error {
     NeitherFeatureNorEnvVar,
     /// Returned when calling methods requiring either a feature or anv var, but both are present
     BothFeatureAndEnvVar,
+    /// Returned when expecting an auto-downloaded executable but `BITCOIND_SKIP_DOWNLOAD` env var is set
+    SkipDownload,
 }
 
 impl fmt::Debug for Error {
@@ -81,6 +83,7 @@ impl fmt::Debug for Error {
             Error::NoEnvVar => write!(f, "Called a method requiring env var `ELECTRUMD_EXE` to be set, but it's not"),
             Error::NeitherFeatureNorEnvVar =>  write!(f, "Called a method requiring env var `ELECTRUMD_EXE` or a feature to be set, but neither are set"),
             Error::BothFeatureAndEnvVar => write!(f, "Called a method requiring env var `ELECTRUMD_EXE` or a feature to be set, but both are set"),
+            Error::SkipDownload => write!(f, "expecting an auto-downloaded executable but `ELECTRUMD_SKIP_DOWNLOAD` env var is set"),
         }
     }
 }
@@ -300,14 +303,16 @@ fn rand_string() -> String {
 
 /// Provide the electrum executable path if a version feature has been specified
 pub fn downloaded_exe_path() -> Result<String, Error> {
-    if versions::HAS_FEATURE {
+    if std::env::var_os("ELECTRUMD_SKIP_DOWNLOAD").is_some() {
+        Err(Error::SkipDownload)
+    } else if !versions::HAS_FEATURE {
+        Err(Error::NoFeature)
+    } else {
         Ok(format!(
             "{}/electrum/electrum-{}/electrum.AppImage",
             env!("OUT_DIR"),
             versions::VERSION
         ))
-    } else {
-        Err(Error::NoFeature)
     }
 }
 
@@ -318,7 +323,9 @@ pub fn exe_path() -> Result<String, Error> {
         (Ok(_), Ok(_)) => Err(Error::BothFeatureAndEnvVar),
         (Ok(path), Err(_)) => Ok(path),
         (Err(_), Ok(path)) => Ok(path),
-        (Err(_), Err(_)) => Err(Error::NeitherFeatureNorEnvVar),
+        (Err(Error::NoFeature), Err(_)) => Err(Error::NeitherFeatureNorEnvVar),
+        (Err(Error::SkipDownload), Err(_)) => Err(Error::SkipDownload),
+        (Err(_), Err(_)) => unreachable!(),
     }
 }