version-helper: always assume we are in a release if not in git

No longer need to have a 'release.txt' file in tarballs.

gst-plugin-version-helper/src/lib.rs

@@ -34,47 +34,28 @@
 
 mod git;
 
+use chrono::TimeZone;
+use std::convert::TryInto;
+use std::time::SystemTime;
 use std::{env, fs, path};
 
 /// Extracts release for GStreamer plugin metadata
 ///
 /// Release information is first tried to be extracted from a git repository at the same
 /// place as the `Cargo.toml`, or one directory up to allow for Cargo workspaces. If no
-/// git repository is found, the information is extract from a `release.txt` in the same
-/// directory as the `Cargo.toml`.
+/// git repository is found, we assume this is a release.
 ///
 /// - If extracted from a git repository, sets the `COMMIT_ID` environment variable to the short
 ///   commit id of the latest commit and the `BUILD_REL_DATE` environment variable to the date of the
 ///   commit.
 ///
-/// - If extracted from a `release.txt`, `COMMIT_ID` will be set to the string `RELEASE` and the
-///   `BUILD_REL_DATE` variable will be set to the release date extracted from `release.txt`.
+/// - If not, `COMMIT_ID` will be set to the string `RELEASE` and the
+///   `BUILD_REL_DATE` variable will be set to the mtime of `Cargo.toml`.
 ///
 /// - If neither is possible, `COMMIT_ID` is set to the string `UNKNOWN` and `BUILD_REL_DATE` to the
 ///   current date.
 ///
-/// ## `release.txt`
-///
-/// `release.txt` is only parsed if no git repository was found and is assumed to be in the format
-///
-/// ```txt
-/// version_number
-/// release_date
-/// ```
-///
-/// for example
-///
-/// ```txt
-/// 1.16.0
-/// 2019-04-19
-/// ```
-///
-/// If the version number from `Cargo.toml` is not equivalent to the one in `release.txt`, this
-/// function will panic.
 pub fn get_info() {
-    let mut commit_id = "UNKNOWN".into();
-    let mut commit_date = chrono::Utc::now().format("%Y-%m-%d").to_string();
-
     let crate_dir =
         path::PathBuf::from(env::var("CARGO_MANIFEST_DIR").expect("CARGO_MANIFEST_DIR not set"));
     let mut repo_dir = crate_dir.clone();
@@ -86,62 +67,25 @@ pub fn get_info() {
         git::repo_hash(&repo_dir)
     });
 
-    let mut release_file = crate_dir.clone();
-    release_file.push("release.txt");
-
     // If there is a git repository, extract the version information from there.
-    // Otherwise use a 'release.txt' file as fallback, or report the current
-    // date and an unknown revision.
-    if let Some((id, date)) = git_info {
-        commit_id = id;
-        commit_date = date;
-    } else if let Ok(release_file) = fs::File::open(release_file) {
-        let mut cargo_toml = crate_dir;
-        cargo_toml.push("Cargo.toml");
-
-        if let Ok(cargo_toml) = fs::File::open(cargo_toml) {
-            commit_date = read_release_date(cargo_toml, release_file);
-            commit_id = "RELEASE".into();
-        }
-    }
+    // Otherwise assume this is a release and use Cargo.toml mtime as date.
+    let (commit_id, commit_date) = git_info.unwrap_or_else(|| {
+        let date = cargo_mtime_date(crate_dir).expect("Failed to get Cargo.toml mtime");
+        ("RELEASE".into(), date)
+    });
 
     println!("cargo:rustc-env=COMMIT_ID={}", commit_id);
     println!("cargo:rustc-env=BUILD_REL_DATE={}", commit_date);
 }
 
-fn read_release_date(mut cargo_toml: fs::File, mut release_file: fs::File) -> String {
-    use std::io::Read;
+fn cargo_mtime_date(crate_dir: path::PathBuf) -> Option<String> {
+    let mut cargo_toml = crate_dir;
+    cargo_toml.push("Cargo.toml");
 
-    let mut content = String::new();
-    release_file
-        .read_to_string(&mut content)
-        .expect("Failed to read version file");
+    let metadata = fs::metadata(&cargo_toml).ok()?;
+    let mtime = metadata.modified().ok()?;
+    let unix_time = mtime.duration_since(SystemTime::UNIX_EPOCH).ok()?;
+    let dt = chrono::Utc.timestamp(unix_time.as_secs().try_into().ok()?, 0);
 
-    let mut lines = content.lines();
-    let version = lines.next().expect("Failed to read version number");
-    let date = lines.next().expect("Failed to read release date");
-
-    let mut cargo_toml_content = String::new();
-    cargo_toml
-        .read_to_string(&mut cargo_toml_content)
-        .expect("Failed to read `Cargo.toml`");
-
-    let cargo_toml = cargo_toml_content
-        .parse::<toml::Value>()
-        .expect("Failed to parse `Cargo.toml`");
-    let package = cargo_toml["package"]
-        .as_table()
-        .expect("Failed to find 'package' section in `Cargo.toml`");
-    let cargo_version = package["version"]
-        .as_str()
-        .expect("Failed to read version from `Cargo.toml`");
-
-    if cargo_version != version {
-        panic!(
-            "Version from 'version.txt' `{}` different from 'Cargo.toml' `{}`",
-            version, cargo_version
-        );
-    }
-
-    date.into()
+    Some(dt.format("%Y-%m-%d").to_string())
 }