Add doc link to README.md

Since we're now using github.com/andybalholm/brotli to natively pack, there's no need to refer
to an external brotli process any more.

README.md

@@ -1,5 +1,7 @@
 # HTTP resource pack server
 
+[![GoDoc](https://img.shields.io/static/v1?label=godoc&message=reference&color=blue)](https://pkg.go.dev/src.lwithers.me.uk/go/htpack)
+
 A common scenario is that you have a set of static resources that you want to
 serve up quickly via HTTP (for example: stylesheets, WASM).
 
@@ -7,7 +9,7 @@ This package provides a `net/http`-compatible `http.Handler` to do so, with
 support for:
 - compression
   - gzip
-  - brotli, if you have the external compression binary available at pack time
+  - brotli
   - does not yet support Transfer-Encoding, only Accept-Encoding/Content-Encoding
 - etags
 - ranges
@@ -28,3 +30,35 @@ else will be ignored.
 The interaction between range handling and compression also seems a little
 ill-defined; as we have pre-compressed data, however, we can consistently
 serve the exact same byte data for compressed files.
+
+## Angular-style single-page application handling
+
+If you wish to support an angular.js-style single page application, in which
+a Javascript application uses the browser's history API to create a set of
+virtual paths ("routes"), it is necessary to somehow intercept HTTP 404 errors
+being returned from the handler and instead return an HTTP 200 with an HTML
+document.
+
+This can be achieved with a number of methods.
+
+If you have an nginx instance reverse proxying in front of `htpack`, then you
+can use a couple of extra directives, for example:
+
+	# prevent page loaded at "http://server.example/my-application" from
+	# requesting resources at "/*" when it should request them at
+	# "/my-application/*" instead
+	location = /my-application {
+		return 308 /my-application/;
+	}
+
+	location /my-application/ {
+		proxy_to http://htpack-addr:8080/;
+		proxy_intercept_errors on;
+		error_page 404 =200 /my-application/;
+	}
+
+If you are using the handler as a library, then you may call
+`handler.SetNotFound(filename)` to select a resource to return (with HTTP 200)
+if a request is made for a resource that is not found. The filename must match
+a packed resource, so it will be preceded with a `/` (for example it may be
+`"/index.html"`).

cmd/htpacker/go.mod

@@ -6,8 +6,10 @@ require (
 	github.com/andybalholm/brotli v1.0.0
 	github.com/foobaz/go-zopfli v0.0.0-20140122214029-7432051485e2
 	github.com/kr/pretty v0.1.0 // indirect
+	github.com/logrusorgru/aurora v0.0.0-20200102142835-e9ef32dff381
 	github.com/spf13/cobra v0.0.5
-	golang.org/x/sys v0.0.0-20200113162924-86b910548bc1
+	github.com/vbauerster/mpb/v4 v4.11.2
+	golang.org/x/sys v0.0.0-20200116001909-b77594299b42
 	gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127 // indirect
 	gopkg.in/yaml.v2 v2.2.2
 	src.lwithers.me.uk/go/htpack v1.1.5

cmd/htpacker/go.sum

@@ -1,4 +1,8 @@
 github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
+github.com/VividCortex/ewma v1.1.1 h1:MnEK4VOv6n0RSY4vtRe3h11qjxL3+t0B8yOL8iMXdcM=
+github.com/VividCortex/ewma v1.1.1/go.mod h1:2Tkkvm3sRDVXaiyucHiACn4cqf7DpdyLvmxzcbUokwA=
+github.com/acarl005/stripansi v0.0.0-20180116102854-5a71ef0e047d h1:licZJFw2RwpHMqeKTCYkitsPqHNxTmd4SNR5r94FGM8=
+github.com/acarl005/stripansi v0.0.0-20180116102854-5a71ef0e047d/go.mod h1:asat636LX7Bqt5lYEZ27JNDcqxfjdBQuJ/MM4CN/Lzo=
 github.com/andybalholm/brotli v1.0.0 h1:7UCwP93aiSfvWpapti8g88vVVGp2qqtGyePsSuDafo4=
 github.com/andybalholm/brotli v1.0.0/go.mod h1:loMXtMfwqflxFJPmdbJO0a3KNoPuLBgiu3qAvBg8x/Y=
 github.com/armon/consul-api v0.0.0-20180202201655-eb2c6b5be1b6/go.mod h1:grANhF5doyWs3UAsr3K4I6qtAmlQcZDesFNEHPZAzj8=
@@ -22,6 +26,8 @@ github.com/kr/pretty v0.1.0/go.mod h1:dAy3ld7l9f0ibDNOQOHHMYYIIbhfbHSm3C4ZsoJORN
 github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
 github.com/kr/text v0.1.0 h1:45sCR5RtlFHMR4UwH9sdQ5TC8v0qDQCHnXt+kaKSTVE=
 github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
+github.com/logrusorgru/aurora v0.0.0-20200102142835-e9ef32dff381 h1:bqDmpDG49ZRnB5PcgP0RXtQvnMSgIF14M7CBd2shtXs=
+github.com/logrusorgru/aurora v0.0.0-20200102142835-e9ef32dff381/go.mod h1:7rIyQOR62GCctdiQpZ/zOJlFyk6y+94wXzv6RNZgaR4=
 github.com/magiconair/properties v1.8.0/go.mod h1:PppfXfuXeibc/6YijjN8zIbojt8czPbwD3XqdrwzmxQ=
 github.com/mitchellh/go-homedir v1.1.0/go.mod h1:SfyaCUpYCn1Vlf4IUYiD9fPX4A5wJrkLzIz1N1q0pr0=
 github.com/mitchellh/mapstructure v1.1.2/go.mod h1:FVVH3fgwuzCH5S8UJGiWEs2h04kUh9fWfEaFds41c1Y=
@@ -38,12 +44,24 @@ github.com/spf13/pflag v1.0.3/go.mod h1:DYY7MBk1bdzusC3SYhjObp+wFpr4gzcvqqNjLnIn
 github.com/spf13/viper v1.3.2/go.mod h1:ZiWeW+zYFKm7srdB9IoDzzZXaJaI5eL9QjNiN/DMA2s=
 github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
 github.com/ugorji/go/codec v0.0.0-20181204163529-d75b2dcb6bc8/go.mod h1:VFNgLljTbGfSG7qAOspJ7OScBnGdDN/yBr0sguwnwf0=
+github.com/vbauerster/mpb/v4 v4.11.2 h1:ynkUoKzi65DZ1UsQPx7sgi/KN6G9f7br+Us2nKm35AM=
+github.com/vbauerster/mpb/v4 v4.11.2/go.mod h1:jIuIRCltGJUnm6DCyPVkwjlLUk4nHTH+m4eD14CdFF0=
 github.com/xordataexchange/crypt v0.0.3-0.20170626215501-b2862e3d0a77/go.mod h1:aYKd//L2LvnjZzWKhF00oedf4jCCReLcmhLdhm1A27Q=
+golang.org/x/crypto v0.0.0-20181203042331-505ab145d0a9 h1:mKdxBk7AujPs8kU4m80U72y/zjbZ3UcXC7dClwKbUI0=
 golang.org/x/crypto v0.0.0-20181203042331-505ab145d0a9/go.mod h1:6SG95UA2DQfeDnfUPMdvaQW0Q7yPrPDi9nlGo2tz2b4=
+golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
+golang.org/x/crypto v0.0.0-20191112222119-e1110fd1c708 h1:pXVtWnwHkrWD9ru3sDxY/qFK/bfc0egRovX91EjWjf4=
+golang.org/x/crypto v0.0.0-20191112222119-e1110fd1c708/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
+golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
 golang.org/x/sys v0.0.0-20181205085412-a5c9d58dba9a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20191113165036-4c7a9d0fe056/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20191228213918-04cbcbbfeed8/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200113162924-86b910548bc1 h1:gZpLHxUX5BdYLA08Lj4YCJNN/jk7KtquiArPoeX0WvA=
 golang.org/x/sys v0.0.0-20200113162924-86b910548bc1/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20200116001909-b77594299b42 h1:vEOn+mP2zCOVzKckCZy6YsCtDblrpj/w7B9nxGNELpg=
+golang.org/x/sys v0.0.0-20200116001909-b77594299b42/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/tools v0.0.0-20180221164845-07fd8470d635/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=

cmd/htpacker/inspector.go

@@ -32,7 +32,6 @@ var inspectCmd = &cobra.Command{
 
 // Inspect a packfile.
 //  TODO: verify etag; verify integrity of compressed data.
-//  TODO: skip Gzip/Brotli if not present; print ratio.
 func Inspect(filename string) error {
 	f, err := os.Open(filename)
 	if err != nil {
@@ -65,10 +64,46 @@ func Inspect(filename string) error {
 					printSize(info.Brotli.Length), info.Brotli.Offset)
 			}
 		}
+		inspectSummary(dir)
 	}
 	return err
 }
 
+func inspectSummary(dir *packed.Directory) {
+	var (
+		n, ngzip, nbrotli int
+		s, sgzip, sbrotli uint64
+	)
+
+	for _, f := range dir.Files {
+		n++
+		s += f.Uncompressed.Length
+		if f.Gzip != nil {
+			ngzip++
+			sgzip += f.Gzip.Length
+		}
+		if f.Brotli != nil {
+			nbrotli++
+			sbrotli += f.Brotli.Length
+		}
+	}
+
+	fmt.Printf("Uncompressed:\n\tFiles: %d\n\tSize:  %s\n",
+		n, printSize(s))
+	if ngzip > 0 {
+		fmt.Printf("gzip compressed:\n\tFiles: %d (%.1f%% of total)\n"+
+			"\tSize:  %s\n\tRatio: %.1f%%\n",
+			ngzip, 100*float64(ngzip)/float64(n),
+			printSize(sgzip), 100*float64(sgzip)/float64(s))
+	}
+	if nbrotli > 0 {
+		fmt.Printf("brotli compressed:\n\tFiles: %d (%.1f%% of total)\n"+
+			"\tSize:  %s\n\tRatio: %.1f%%\n",
+			nbrotli, 100*float64(nbrotli)/float64(n),
+			printSize(sbrotli), 100*float64(sbrotli)/float64(s))
+	}
+}
+
 func printSize(size uint64) string {
 	switch {
 	case size < 1<<10:

cmd/htpacker/pack.go

@@ -10,6 +10,7 @@ import (
 	"github.com/spf13/cobra"
 	yaml "gopkg.in/yaml.v2"
 	"src.lwithers.me.uk/go/htpack/cmd/htpacker/packer"
+	"src.lwithers.me.uk/go/htpack/packed"
 )
 
 var packCmd = &cobra.Command{
@@ -89,7 +90,8 @@ func PackFiles(c *cobra.Command, args []string, out string) error {
 	if err != nil {
 		return err
 	}
-	return packer.Pack(ftp, out)
+
+	return doPack(ftp, out)
 }
 
 func PackSpec(c *cobra.Command, spec, out string) error {
@@ -103,5 +105,26 @@ func PackSpec(c *cobra.Command, spec, out string) error {
 		return fmt.Errorf("parsing YAML spec %s: %v", spec, err)
 	}
 
-	return packer.Pack(ftp, out)
+	return doPack(ftp, out)
+}
+
+func doPack(ftp packer.FilesToPack, out string) error {
+	prog := mpbProgress(ftp)
+	err := packer.Pack2(ftp, out, prog)
+	prog.Complete()
+
+	if err == nil {
+		fin, err := os.Open(out)
+		if err != nil {
+			return err
+		}
+		defer fin.Close()
+
+		_, dir, err := packed.Load(fin)
+		if err != nil {
+			return err
+		}
+		inspectSummary(dir)
+	}
+	return err
 }

cmd/htpacker/pack_progress.go

@@ -0,0 +1,144 @@
+package main
+
+import (
+	"github.com/logrusorgru/aurora"
+	"github.com/vbauerster/mpb/v4"
+	"github.com/vbauerster/mpb/v4/decor"
+	"src.lwithers.me.uk/go/htpack/cmd/htpacker/packer"
+)
+
+const mpbBarStyle = "[██░]"
+
+// mpbProgress returns a new progress object that keeps the user informed via
+// the visual mpb library.
+func mpbProgress(ftp packer.FilesToPack) *mpbProg {
+	mp := new(mpbProg)
+	mp.un.max = len(ftp)
+
+	for _, f := range ftp {
+		if !f.DisableCompression && !f.DisableGzip {
+			mp.gzip.max++
+		}
+		if !f.DisableCompression && !f.DisableBrotli {
+			mp.brotli.max++
+		}
+	}
+
+	mp.p = mpb.New()
+	mp.un.bar = mp.p.AddBar(int64(mp.un.max),
+		mpb.PrependDecorators(barName("uncompressed")),
+		mpb.BarStyle(mpbBarStyle),
+		mpb.AppendDecorators(&mp.un))
+	if mp.gzip.max > 0 {
+		mp.gzip.bar = mp.p.AddBar(int64(mp.gzip.max),
+			mpb.PrependDecorators(barName("gzip")),
+			mpb.BarStyle(mpbBarStyle),
+			mpb.AppendDecorators(&mp.gzip))
+	}
+	if mp.brotli.max > 0 {
+		mp.brotli.bar = mp.p.AddBar(int64(mp.brotli.max),
+			mpb.PrependDecorators(barName("brotli")),
+			mpb.BarStyle(mpbBarStyle),
+			mpb.AppendDecorators(&mp.brotli))
+	}
+
+	return mp
+}
+
+func barName(n string) decor.Decorator {
+	return decor.Name(aurora.Magenta(n).String(), decor.WCSyncWidth)
+}
+
+// mpbProg is the mpb progress tracker. It has one bar for each type of
+// compression, and its methods simply dispatch onto the type-specific
+// bars.
+type mpbProg struct {
+	un, gzip, brotli mpbProg1
+	p                *mpb.Progress
+}
+
+func (mp *mpbProg) Count(_ int) {
+}
+
+func (mp *mpbProg) Begin(filename, compression string) {
+	switch compression {
+	case "uncompressed":
+		mp.un.Begin(filename)
+	case "gzip":
+		mp.gzip.Begin(filename)
+	case "brotli":
+		mp.brotli.Begin(filename)
+	default:
+		return
+	}
+}
+
+func (mp *mpbProg) End(filename, compression string) {
+	switch compression {
+	case "uncompressed":
+		mp.un.End(filename)
+	case "gzip":
+		mp.gzip.End(filename)
+	case "brotli":
+		mp.brotli.End(filename)
+	default:
+		return
+	}
+}
+
+func (mp *mpbProg) Complete() {
+	mp.un.Complete()
+	mp.gzip.Complete()
+	mp.brotli.Complete()
+	mp.p.Wait()
+}
+
+// mpbProg1 is a type-specific progress bar. In addition to holding state and
+// methods for updating the bar, it also implements decor.Decor.
+type mpbProg1 struct {
+	max  int      // number of items we expect
+	done int      // number of items completed
+	cur  []string // list of currently-packing filenames
+	bar  *mpb.Bar
+
+	// embedding this type lets us implement decor.Decor
+	decor.WC
+}
+
+func (mp1 *mpbProg1) Decor(stat *decor.Statistics) string {
+	if stat.Completed {
+		return ""
+	}
+	switch len(mp1.cur) {
+	case 0:
+		return aurora.Gray(8, "(idle)").String()
+	case 1:
+		return aurora.Blue(mp1.cur[0]).String()
+	default:
+		return aurora.Sprintf(aurora.Green("%s + %d more"), aurora.Blue(mp1.cur[0]), len(mp1.cur)-1)
+	}
+}
+
+func (mp1 *mpbProg1) Begin(filename string) {
+	mp1.cur = append(mp1.cur, filename)
+}
+
+func (mp1 *mpbProg1) End(filename string) {
+	for i, v := range mp1.cur {
+		if v == filename {
+			mp1.cur[i] = mp1.cur[len(mp1.cur)-1]
+			mp1.cur = mp1.cur[:len(mp1.cur)-1]
+			break
+		}
+	}
+	mp1.done++
+	if mp1.bar != nil {
+		mp1.bar.SetCurrent(int64(mp1.done))
+	}
+}
+
+func (mp1 *mpbProg1) Complete() {
+	if mp1.bar != nil {
+		mp1.bar.SetTotal(int64(mp1.max), true)
+	}
+}

cmd/htpacker/packer/packer.go

@@ -45,6 +45,24 @@ type FileToPack struct {
 	DisableBrotli bool `yaml:"disable_brotli"`
 }
 
+// Progress is a callback object which reports packing progress.
+type Progress interface {
+	// Count reports the number of items that have begun processing.
+	Count(n int)
+
+	// Begin denotes the processing of an input file.
+	Begin(filename, compression string)
+
+	// End denotes the completion of input file processing.
+	End(filename, compression string)
+}
+
+type ignoreProgress int
+
+func (ignoreProgress) Count(_ int)       {}
+func (ignoreProgress) Begin(_, _ string) {}
+func (ignoreProgress) End(_, _ string)   {}
+
 const (
 	// minCompressionSaving means we'll only use the compressed version of
 	// the file if it's at least this many bytes smaller than the original.
@@ -68,8 +86,18 @@ const (
 	sendfileLimit = 0x7FFFF000
 )
 
-// Pack a file.
+// Pack a file. Use Pack2 for progress reporting.
 func Pack(filesToPack FilesToPack, outputFilename string) error {
+	return Pack2(filesToPack, outputFilename, nil)
+}
+
+// Pack2 will pack a file, with progress reporting. The progress interface may
+// be nil.
+func Pack2(filesToPack FilesToPack, outputFilename string, progress Progress) error {
+	if progress == nil {
+		progress = ignoreProgress(0)
+	}
+
 	finalFname, w, err := writefile.New(outputFilename)
 	if err != nil {
 		return err
@@ -80,6 +108,7 @@ func Pack(filesToPack FilesToPack, outputFilename string) error {
 	// it has a couple of convenience methods for common operations
 	packer := packer{
 		w:        w,
+		progress: progress,
 	}
 
 	// write initial header (will rewrite offset/length when known)
@@ -124,6 +153,7 @@ func Pack(filesToPack FilesToPack, outputFilename string) error {
 		Files: make(map[string]*packed.File),
 	}
 
+	var count int
 PackingLoop:
 	for path, fileToPack := range filesToPack {
 		select {
@@ -132,6 +162,8 @@ PackingLoop:
 			break PackingLoop
 		default:
 			packer.packFile(path, fileToPack)
+			count++
+			progress.Count(count)
 		}
 	}
 
@@ -205,6 +237,7 @@ type packer struct {
 	errors   chan error
 	aborted  chan struct{}
 	dir      *packed.Directory
+	progress Progress
 }
 
 // pad will move the file write pointer to the next padding boundary. It is not
@@ -312,11 +345,15 @@ func (p *packer) packFile(path string, fileToPack FileToPack) {
 	// list of operations on this input file that we'll carry out asynchronously
 	ops := []func() error{
 		func() error {
+			p.progress.Begin(fileToPack.Filename, "uncompressed")
+			defer p.progress.End(fileToPack.Filename, "uncompressed")
 			return p.Uncompressed(fileToPack.Filename, info)
 		},
 	}
 	if !fileToPack.DisableCompression && !fileToPack.DisableGzip {
 		ops = append(ops, func() error {
+			p.progress.Begin(fileToPack.Filename, "gzip")
+			defer p.progress.End(fileToPack.Filename, "gzip")
 			if err := p.Gzip(data, info); err != nil {
 				return fmt.Errorf("gzip compression of %s "+
 					"failed: %v", fileToPack.Filename, err)
@@ -326,6 +363,8 @@ func (p *packer) packFile(path string, fileToPack FileToPack) {
 	}
 	if !fileToPack.DisableCompression && !fileToPack.DisableBrotli {
 		ops = append(ops, func() error {
+			p.progress.Begin(fileToPack.Filename, "brotli")
+			defer p.progress.End(fileToPack.Filename, "brotli")
 			if err := p.Brotli(data, info); err != nil {
 				return fmt.Errorf("brotli compression of %s "+
 					"failed: %v", fileToPack.Filename, err)

handler.go

@@ -72,6 +72,7 @@ type Handler struct {
 	dir       map[string]*packed.File
 	headers   map[string]string
 	startTime time.Time
+	notFound  *packed.File
 }
 
 // SetHeader allows a custom header to be set on HTTP responses. These are
@@ -110,6 +111,28 @@ func (h *Handler) SetIndex(filename string) {
 	}
 }
 
+// SetNotFound allows overriding the returned resource when a request is made
+// for a resource that does not exist. The default behaviour would be to return
+// a standard HTTP 404 Not Found response; calling this function with an empty
+// string will restore that behaviour.
+//
+// This function will return an error if the named resource is not present in
+// the packfile.
+func (h *Handler) SetNotFound(notFound string) error {
+	if notFound == "" {
+		h.notFound = nil
+		return nil
+	}
+
+	notFound = path.Clean(notFound)
+	dir := h.dir[path.Clean(notFound)]
+	if dir == nil {
+		return fmt.Errorf("no such resource %q", notFound)
+	}
+	h.notFound = dir
+	return nil
+}
+
 // ServeHTTP handles requests for files. It supports GET and HEAD methods, with
 // anything else returning a 405. Exact path matches are required, else a 404 is
 // returned.
@@ -130,9 +153,12 @@ func (h *Handler) ServeHTTP(w http.ResponseWriter, req *http.Request) {
 
 	info := h.dir[path.Clean(req.URL.Path)]
 	if info == nil {
+		if h.notFound == nil {
 			http.NotFound(w, req)
 			return
 		}
+		info = h.notFound
+	}
 
 	// set standard headers
 	w.Header().Set("Vary", "Accept-Encoding")