diff --git a/blog/crazy-experiment-2017-01-09.markdown b/blog/crazy-experiment-2017-01-09.markdown new file mode 100644 index 0000000..3bde1d2 --- /dev/null +++ b/blog/crazy-experiment-2017-01-09.markdown @@ -0,0 +1,59 @@ +--- +title: "Crazy Experiment: Frontend Shipping as asar" +date: "2017-01-09" +--- + +Today's crazy experiment is using an [asar archive](https://github.com/electron/asar) for shipping around +and mounting frontend Javascript applications. This is something I feel is worth doing because it allows +the web frontend developer (or team) give the backend team a single "binary" that can be dropped into the +deployment process without having to build the frontend code as part of CI. + +asar is an interesting file format because it allows for random access of the data inside the archive. +This allows an HTTP server to be able to concurrently serve files out of it without having to lock or +incur an additional open file descriptor. + +In order to implement this, I have created a Go package named [asarfs](https://github.com/Xe/asarfs) that +exposes the contents of an asar archive as a standard http.Handler. + +Example Usage: + +```go +package main + +import ( + "log" + "net/http" + "os" + + "github.com/Xe/asarfs" +) + +func do404(w http.ResponseWriter, r *http.Request) { + http.Error(w, "Not found", http.StatusNotFound) +} + +func main() { + fs, err := asarfs.New("./static.asar", http.HandlerFunc(do404)) + if err != nil { + log.Fatal(err) + } + + http.ListenAndServe(":"+os.Getenv("PORT"), fs) +} +``` + +I made some contrived benchmarks using some sample data (lots of large json files from mongodb dumps) +I had laying around and ran them a few times. The results were very promising: + +```console +[~/g/s/g/X/asarfs] : go1.8beta2 test -bench=. -benchmem +BenchmarkHTTPFileSystem-8 20000 66481 ns/op 3219 B/op 58 allocs/op +BenchmarkASARfs-8 20000 72084 ns/op 3549 B/op 77 allocs/op +BenchmarkPreloadedASARfs-8 20000 62894 ns/op 3218 B/op 58 allocs/op +PASS +ok github.com/Xe/asarfs 5.636s +``` + +Amazingly, the performance and memory usage differences between serving the files over an asar archive +and off of the filesystem are negligible. I've implemented it in the latest release of my personal website +and hopefully end users should be seeing no difference in page load times.