Remove the from-source feature (#39)

Prior to this change, the `openvino-sys` crate had the ability to build
OpenVINO from source using CMake from within its `build.rs` script. This
increased complexity in various places (documentation, `Cargo.toml`
features, `build.rs`) and was prone to breakage as OpenVINO modified its
available CMake build features.

Instead of providing a `from-source` feature to do all this, this change
documents an `OPENVINO_BUILD_DIR` environment variable that can be used
for the same purpose: once a user has built OpenVINO from source on
their system, they can provide the path to this repository for the
`openvino-sys` crate to bind to. The `openvino-finder` crate contains
the necessary paths to find the default locations of all of required
libraries.

Author: abrown

.github/workflows/main.yml

@@ -31,28 +31,6 @@ jobs:
     - uses: actions/checkout@v2
     - uses: EmbarkStudios/cargo-deny-action@v1
 
-  # Build and test from the git-submodule-included OpenVINO source code.
-  source:
-    name: From source
-    runs-on: ubuntu-20.04
-    steps:
-    - uses: actions/checkout@v2
-      with:
-        submodules: recursive
-        lfs: true
-    - name: Checkout LFS obects
-      run: git lfs checkout
-    - name: Install system dependencies
-      run: sudo apt update && sudo apt install -y clang cmake libclang-dev gnupg2 libdrm2 libglib2.0-0 libusb-1.0-0-dev lsb-release libgtk-3-0 libtool udev unzip dos2unix
-    - name: Build (openvino-sys from source)
-      run: cargo build --verbose --features openvino-sys/from-source
-    - name: Run tests
-      # For some reason the library path is not set during the doc tests (`--doc`, see
-      # https://doc.rust-lang.org/cargo/commands/cargo-test.html#target-selection) so we skip them
-      # here: issue at https://github.com/intel/openvino-rs/issues/25. Also, the `from-source` build
-      # does not know how to run the inception SSD test.
-      run: cargo test --verbose --features openvino-sys/from-source --lib --tests -- --skip detect_inception
-
   # Build and test from an existing OpenVINO installation inside a Docker image (i.e. download the
   # binaries, then compile against these).
   dynamic_binaries:

Cargo.lock

@@ -6,8 +6,9 @@
 This repository contains the [openvino-sys] crate (low-level, unsafe bindings) and the [openvino]
 crate (high-level, ergonomic bindings) for accessing OpenVINO™ functionality in Rust.
 
-[openvino-sys]: crates/openvino-sys
 [openvino]: crates/openvino
+[openvino-sys]: crates/openvino-sys
+[openvino-finder]: crates/openvino-finder
 [upstream]: crates/openvino-sys/upstream
 [docs]: https://docs.rs/openvino
 [ci]: https://github.com/abrown/openvino-rs/actions?query=workflow%3ACI
@@ -39,15 +40,14 @@ source /opt/intel/openvino/setupvars.sh
 cargo test
 ```
 
-The quickest method to build [openvino] and [openvino-sys] is with a local installation of OpenVINO™
-(see, e.g., [installing from an apt repository][install-apt]). The build script will attempt to
-locate an existing installation (see [openvino-finder]) and link against its shared libraries.
-Provide the `OPENVINO_INSTALL_DIR` environment variable to point at a specific installation. Ensure
-that the correct libraries are available on the system's load path; OpenVINO™'s `setupvars.sh`
-script will do this automatically.
+The quickest method to build the [openvino] and [openvino-sys] crates is with a local installation
+of OpenVINO™ (see, e.g., [installing from an apt repository][install-apt]). The build script will
+attempt to locate an existing installation (see [openvino-finder]) and link against its shared
+libraries. Provide the `OPENVINO_INSTALL_DIR` environment variable to point at a specific
+installation. Ensure that the correct libraries are available on the system's load path; OpenVINO™'s
+`setupvars.sh` script will do this automatically.
 
 [install-apt]: https://docs.openvinotoolkit.org/latest/openvino_docs_install_guides_installing_openvino_apt.html
-[openvino-finder]: crates/openvino-finder
 
 
 
@@ -70,26 +70,28 @@ high-level users, call `openvino::Core::new` first to automatically load and lin
 
 ### Build from OpenVINO™ sources
 
+First, build OpenVINO by cloning the [openvino] repository and following the [OpenVINO™ build
+documentation]. Then, using the top-level directory as `<openvino-repo>` (not the CMake build
+directory), build this crate:
+
 ```shell script
-git submodule update --init --recursive
-cargo build -vv --features openvino-sys/from-source
-cargo test --features openvino-sys/from-source
+OPENVINO_BUILD_DIR=<openvino-repo> cargo build
+OPENVINO_BUILD_DIR=<openvino-repo> cargo test
 ```
 
-[openvino] and [openvino-sys] can also be built directly from OpenVINO™'s source code using CMake.
-This is not tested across all OS and OpenVINO™ versions--use at your own risk! Also, this build
-process can be quite slow and there are quite a few dependencies. Some notes:
- - first, install the necessary packages to build OpenVINO™; steps are included in the [CI
-   workflow](.github/workflows)
-   but reference the [OpenVINO™ build documentation](https://github.com/openvinotoolkit/openvino/blob/master/build-instruction.md)
-   for the full documentation
- - OpenVINO™ has a plugin system for device-specific libraries (e.g. GPU); building all of these
-   libraries along with the core inference libraries can take >20 minutes. To avoid over-long build
-   times, [openvino-sys] exposes several Cargo features. By default, [openvino-sys] will only build
-   the CPU plugin; to build all plugins, use `--features all` (see
-   [Cargo.toml](crates/openvino-sys/Cargo.toml)).
- - OpenVINO™ includes other libraries (e.g. ngraph, tbb); see the
-   [build.rs](crates/openvino-sys/build.rs) file for how these are linked to these libraries.
+Some important notes about the path passed in `OPENVINO_BUILD_DIR`:
+- `<openvino-repo>` should be an absolute path (or at least a path relative to the
+  `crates/openvino-sys` directory, which is the current directory when used at build time)
+- `<openvino-repo>` should either be outside of this crate's tree or in the `target` directory (see
+  the limitations on [`cargo:rustc-link-search`]).
+
+The various OpenVINO libraries and dependencies are found using the [openvino-finder] crate. Turn on
+logging to troubleshoot any issues finding the right libraries, e.g., `RUST_LOG=info
+OPENVINO_BUILD_DIR=... cargo build -vv`.
+
+[openvino]: https://github.com/openvinotoolkit/openvino
+[OpenVINO™ build documentation]: https://github.com/openvinotoolkit/openvino/blob/master/build-instruction.md
+[`cargo:rustc-link-search`]: https://doc.rust-lang.org/cargo/reference/build-scripts.html#rustc-link-search
 
 
 

README.md

@@ -35,21 +35,21 @@ pub fn find(library_name: &str) -> Option<PathBuf> {
         };
     }
 
-    // Search using the `OPENVINO_INSTALL_DIR` environment variable; this may be set by users of the
+    // Search using the `OPENVINO_BUILD_DIR` environment variable; this may be set by users of the
     // `openvino-rs` library.
-    if let Some(install_dir) = env::var_os(ENV_OPENVINO_INSTALL_DIR) {
-        let install_dir = PathBuf::from(install_dir);
-        for lib_dir in KNOWN_INSTALLATION_SUBDIRECTORIES {
+    if let Some(build_dir) = env::var_os(ENV_OPENVINO_BUILD_DIR) {
+        let install_dir = PathBuf::from(build_dir);
+        for lib_dir in KNOWN_BUILD_SUBDIRECTORIES {
             let search_path = install_dir.join(lib_dir).join(&file);
             check_and_return!(search_path);
         }
     }
 
-    // Search using the `OPENVINO_BUILD_DIR` environment variable; this may be set by users of the
+    // Search using the `OPENVINO_INSTALL_DIR` environment variable; this may be set by users of the
     // `openvino-rs` library.
-    if let Some(build_dir) = env::var_os(ENV_OPENVINO_BUILD_DIR) {
-        let install_dir = PathBuf::from(build_dir);
-        for lib_dir in KNOWN_BUILD_SUBDIRECTORIES {
+    if let Some(install_dir) = env::var_os(ENV_OPENVINO_INSTALL_DIR) {
+        let install_dir = PathBuf::from(install_dir);
+        for lib_dir in KNOWN_INSTALLATION_SUBDIRECTORIES {
             let search_path = install_dir.join(lib_dir).join(&file);
             check_and_return!(search_path);
         }

crates/openvino-finder/src/lib.rs

@@ -30,29 +30,13 @@ libloading = {version = "0.7", optional = true }
 openvino-finder = {version = "0.3.3", path = "../openvino-finder" }
 
 [build-dependencies]
-cmake = "0.1.45"
 openvino-finder = {version = "0.3.3", path = "../openvino-finder" }
+pretty_env_logger = "0.4"
 
 [features]
-default = ["cpu"]
-
-# Plugin features: if building from source, this allows selecting which OpenVINO plugins to build.
-all = ["auto", "auto_batch", "cpu", "gpu", "gna", "hetero", "myriad", "multi"]
-auto = []
-auto_batch = []
-cpu = []
-gpu = []
-gna = []
-hetero = []
-myriad = []
-multi = []
-
 # Linking features: `build.rs` will default to dynamic linking if none is selected.
 dynamic-linking = [] # Will find and bind to an OpenVINO shared library at compile time.
 runtime-linking = ["libloading", "lazy_static"] # Will bind to an OpenVINO shared library at runtime using `load`.
 
-# Build features: `build.rs` will attempt to build OpenVINO from source and then link to this.
-from-source = []
-
 [package.metadata.docs.rs]
 features = ["runtime-linking"]