| # platform/loader/ |
| |
| ## Loading and Freezing |
| |
| Loaders (i.e., blink::ResourceLoaders and related objects) run on unfreezable |
| task runners, which means even when the associated page is frozen a loader is |
| still running. This is because having frozen loaders for a long time |
| confuses the network service and the resource scheduler in it. On the other |
| hand, it would be difficult for blink code authors to handle the situation |
| where the loading module is working while everything else is frozen |
| correctly, given that loading experts are not necessarily freezing experts. |
| To mitigate the pain, we run only part of the loading module when the page |
| is frozen. Namely, |
| |
| - blink::MojoURLLoaderClient |
| - blink::ResponseBodyLoader |
| - blink::ResourceRequestClient implementations |
| - blink::ThrottlingURLLoader implementations |
| - blink::BackForwardCacheLoaderHelper implementations |
| |
| may run when the associated context is frozen, and other modules won't run |
| (except for the case where they are called from outside of the loading |
| module). To guarantee this, blink::ResourceFetcher::SetDefersLoading needs |
| to be called when the associated context gets frozen and unfrozen. |
| |
| ## Directory organization |
| |
| ### cors |
| |
| Contains Cross-Origin Resource Sharing (CORS) related files. Some functions |
| in this directory will be removed once CORS support is moved to |
| //services/network. Please contact {kinuko,toyoshim}@chromium.org when you need |
| to depend on this directory from new code. |
| |
| ### fetch |
| |
| Contains files for low-level loading APIs. The `PLATFORM_EXPORT` macro is |
| needed to use them from `core/`. Otherwise they can be used only in |
| `platform/`. |
| |
| The directory conceptually implements https://fetch.spec.whatwg.org/#fetching |
| (with lower-level components such as the network service). See also: [slides |
| describing the relationship with the fetch spec](https://docs.google.com/presentation/d/1r9KHuYbNlgqQ6UABAMiWz0ONTpSTnMaDJ8UeYZGWjls/) |
| |
| ### testing |
| |
| Contains helper files for testing that are available in both |
| `blink_platform_unittests` and `blink_unittests`. |
| These files are built as a part of the `platform:test_support` static library. |
