[Core] Full file:// syntax support

Closes #14. Fully support `file` URLs by making use the OpenAssetIO
`FileUrlPathConverter` utility.

The utility will throw on non-`file` URLs being provided, maintaining
existing behaviour (with a slightly different error message). Confirmed
with manual testing.

The `FileUrlPathConverter` utility is only available as of OpenAssetIO
1.0.0-beta.2.0. So update README.

Signed-off-by: David Feltell <[email protected]>

README.md

@@ -81,13 +81,15 @@ limitations.
 
 ## Dependencies
 
-### [OpenAssetIO](https://github.com/OpenAssetIO/OpenAssetIO/) (1.0.0-alpha.14)
+### [OpenAssetIO](https://github.com/OpenAssetIO/OpenAssetIO/) (1.0.0-beta.2.0)
 
-Currently, OpenAssetIO must be built from source to build
-`usdOpenAssetIOResolver`.
+The OpenAssetIO libary is available pre-built for some common platforms
+are available
+[here](https://github.com/OpenAssetIO/OpenAssetIO/releases).
 
-The steps to do this can be found
-[here.](https://github.com/OpenAssetIO/OpenAssetIO/blob/main/doc/BUILDING.md)
+Alternatively, OpenAssetIO can be built from source. The steps to do
+this can be found
+[here](https://github.com/OpenAssetIO/OpenAssetIO/blob/main/doc/BUILDING.md).
 
 ### [USD](https://github.com/PixarAnimationStudios/USD) (22.11)
 

src/resolver.cpp

@@ -3,6 +3,7 @@
 
 #include "resolver.h"
 
+#include <optional>
 #include <stdexcept>
 #include <thread>
 
@@ -20,7 +21,7 @@
 #include <openassetio/log/LoggerInterface.hpp>
 #include <openassetio/log/SeverityFilter.hpp>
 #include <openassetio/python/hostApi.hpp>
-#include <openassetio/trait/TraitsData.hpp>
+#include <openassetio/utils/path.hpp>
 
 #include <openassetio_mediacreation/traits/content/LocatableContentTrait.hpp>
 
@@ -35,21 +36,6 @@ TF_DEBUG_CODES(OPENASSETIO_RESOLVER)
 PXR_NAMESPACE_CLOSE_SCOPE
 
 namespace {
-/*
- * Replaces all occurrences of the search string in the subject with
- * the supplied replacement.
- */
-void replaceAllInString(std::string &subject, const std::string &search,
-                        const std::string &replace) {
-  const size_t searchLength = search.length();
-  const size_t replaceLength = replace.length();
-  size_t pos = 0;
-  while ((pos = subject.find(search, pos)) != std::string::npos) {
-    subject.replace(pos, searchLength, replace);
-    pos += replaceLength;
-  }
-}
-
 /*
  * OpenAssetIO LoggerInterface implementation
  *
@@ -239,27 +225,20 @@ class UsdOpenAssetIOResolver::Impl {
     const openassetio::trait::TraitsDataPtr traitsData = manager_->resolve(
         entityReference, {LocatableContentTrait::kId}, ResolveAccess::kRead, context_);
 
-    // OpenAssetIO is URL based, but we need a path, so check the
-    // scheme and decode into a path
-
-    static constexpr std::string_view kFileURLScheme{"file://"};
-    static constexpr std::size_t kProtocolSize = kFileURLScheme.size();
-
-    openassetio::Str url = LocatableContentTrait(traitsData).getLocation();
-    if (url.rfind(kFileURLScheme, 0) == openassetio::Str::npos) {
-      std::string msg = "Only file URLs are supported: ";
-      msg += url;
-      throw std::runtime_error(msg);
+    const std::optional<openassetio::Str> url = LocatableContentTrait(traitsData).getLocation();
+    if (!url) {
+      throw std::invalid_argument{"Entity reference does not have a location: " +
+                                  entityReference.toString()};
     }
-
-    // TODO(tc): Decode % escape sequences properly
-    replaceAllInString(url, "%20", " ");
-    return url.substr(kProtocolSize);
+    // OpenAssetIO is URL based, but we need a path. Note: will throw if
+    // the URL is not valid.
+    return fileUrlPathConverter_.pathFromUrl(*url);
   }
 
   openassetio::log::LoggerInterfacePtr logger_;
   openassetio::hostApi::ManagerPtr manager_;
   openassetio::ContextConstPtr context_;
+  openassetio::utils::FileUrlPathConverter fileUrlPathConverter_;
 };
 
 UsdOpenAssetIOResolver::UsdOpenAssetIOResolver() : impl_{std::make_unique<Impl>()} {}

tests/resources/integration_test_data/bal_library.json

@@ -28,7 +28,7 @@
                     "traits": {
                         "openassetio-mediacreation:content.LocatableContent": {
                             "location":
-                            "file://${bal_library_dir}/recursive_assetized_resolve/floors/floor%201.usd"
+                            "file://${bal_library_dir}/recursive_assetized_resolve/floors/floor%20%40%201.usd"
                         }
                     }
                 }