http: Update env vars for build process

Use the standard `SOURCE_DATE_EPOCH` instead of `GIT_COMMIT_TIME`.
Set `GIT_HEAD` properly.

radicle-httpd/build.rs

@@ -27,8 +27,8 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
         "pre-release".to_owned()
     };
 
-    // Set a build-time `GIT_COMMIT_TIME` env var which includes the commit time.
-    let commit_time = env::var("GIT_COMMIT_TIME").unwrap_or_else(|_| {
+    // Set a build-time `SOURCE_DATE_EPOCH` env var which includes the commit time.
+    let commit_time = env::var("SOURCE_DATE_EPOCH").unwrap_or_else(|_| {
         Command::new("git")
             .arg("log")
             .arg("-1")
@@ -47,7 +47,7 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
     });
 
     println!("cargo::rustc-env=RADICLE_VERSION={version}");
-    println!("cargo::rustc-env=GIT_COMMIT_TIME={commit_time}");
+    println!("cargo::rustc-env=SOURCE_DATE_EPOCH={commit_time}");
     println!("cargo::rustc-env=GIT_HEAD={hash}");
 
     Ok(())

radicle-httpd/build/Dockerfile

@@ -8,6 +8,7 @@ ARG TZ
 ARG LC_ALL
 ARG SOURCE_DATE_EPOCH
 ARG RADICLE_VERSION
+ARG GIT_HEAD
 
 # Copy cargo configuration we're going to use to specify compiler options.
 RUN mkdir -p .cargo && cp build/config.toml .cargo/config.toml

radicle-httpd/build/build

@@ -53,6 +53,7 @@ main() {
       --build-arg TZ \
       --build-arg LC_ALL \
       --build-arg RADICLE_VERSION=$version \
+      --build-arg GIT_HEAD=$rev \
       --arch aarch64 --tag $image -f ./build/Dockerfile - <$gitarchive
 
     echo "Creating container (radicle-build-container).."