diff --git a/README.md b/README.md index f6f0374..60d12dc 100644 --- a/README.md +++ b/README.md @@ -24,8 +24,8 @@ are quite important. Previous solutions (for example [`vfsgen`](https://github.c with [`httpgzip`](https://github.com/shurcooL/httpgzip)) can optimize performance by storing compressed assets and serving them directly to capable user agents. This library implements such functionality for embedded file systems. -> **_NOTE:_** Unfortunately guarding new api with build tags is not a viable option, since it imposes -> [issues](https://github.com/golang/go/issues/43400) in older versions of Go. +> **_NOTE:_** Guarding new api (`embed`) with build tags is not a viable option, since it imposes +> [issue](https://github.com/golang/go/issues/43400) in older versions of Go. ## Example @@ -63,14 +63,6 @@ Behavior is based on [nginx gzip static module](http://nginx.org/en/docs/http/ng Static assets have to be manually compressed with additional file extension, e.g. `bundle.js` would become `bundle.js.gz` (compressed with gzip) or `index.html` would become `index.html.br` (compressed with brotli). -> **_NOTE:_** Although [`brotli`](https://github.com/google/brotli) has better compression than `gzip` and already -> has wide support in browsers, it has limitations for non-https servers, -> see [this](https://bugs.chromium.org/p/chromium/issues/detail?id=452335) -> and [this](https://bugzilla.mozilla.org/show_bug.cgi?id=1218924). - -> **_NOTE:_** `brotli` support is optional. Using `brotli` adds about 260 KB to binary size, that's why it is moved to -> a separate package. - > **_NOTE:_** [`zopfli`](https://github.com/google/zopfli) provides better compression than `gzip` while being > backwards compatible with it. @@ -81,3 +73,23 @@ e.g. `bundle.js`). If uncompressed file is not available, then server would deco Responses have `ETag` headers (64-bit FNV-1 hash of file contents) to enable caching. Responses that are not dynamically decompressed are served with [`http.ServeContent`](https://golang.org/pkg/net/http/#ServeContent) for ranges support. + +### Brotli support + +Support for `brotli` is optional. Using `brotli` adds about 260 KB to binary size, that's why it is moved to +a separate package. + +> **_NOTE:_** Although [`brotli`](https://github.com/google/brotli) has better compression than `gzip` and already +> has wide support in browsers, it has limitations for non-https servers, +> see [this](https://bugs.chromium.org/p/chromium/issues/detail?id=452335) +> and [this](https://bugzilla.mozilla.org/show_bug.cgi?id=1218924). + +### Runtime encoding + +Recommended way of embedding assets is to compress assets before the build, so that binary includes `*.gz` or `*.br` files. +This can be inconvenient in some cases, there is `EncodeOnInit` option to compress assets in runtime when creating file server. +Once compressed, assets will be served directly without additional dynamic compression. + +Files with extensions ".gz", ".br", ".gif", ".jpg", ".png", ".webp" are excluded from runtime encoding by default. + +> **_NOTE:_** Compressing assets in runtime can degrade startup performance and increase memory usage to prepare and store compressed data.