Improved binary/text files identification (#176)

* Testing usage of xyproto/binary library

* Usage of mimetyp library

* Add more test cases

* Add test for HCL file

go.mod

@@ -21,13 +21,16 @@ require (
 	github.com/stretchr/testify v1.7.2
 	github.com/stuart-warren/yamlfmt v0.1.2
 	github.com/urfave/cli/v2 v2.26.0
-	golang.org/x/crypto v0.3.0 // indirect
-	golang.org/x/sys v0.2.0 // indirect
-	golang.org/x/term v0.2.0 // indirect
+	golang.org/x/crypto v0.14.0 // indirect
+	golang.org/x/sys v0.13.0 // indirect
+	golang.org/x/term v0.13.0 // indirect
 	gopkg.in/yaml.v2 v2.4.0
 )
 
-require github.com/google/go-cmp v0.5.7
+require (
+	github.com/gabriel-vasile/mimetype v1.4.3
+	github.com/google/go-cmp v0.5.7
+)
 
 require (
 	cloud.google.com/go v0.83.0 // indirect
@@ -81,11 +84,11 @@ require (
 	github.com/zclconf/go-cty v1.9.1 // indirect
 	go.opencensus.io v0.23.0 // indirect
 	golang.org/x/lint v0.0.0-20210508222113-6edffad5e616 // indirect
-	golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4 // indirect
-	golang.org/x/net v0.2.0 // indirect
+	golang.org/x/mod v0.8.0 // indirect
+	golang.org/x/net v0.17.0 // indirect
 	golang.org/x/oauth2 v0.0.0-20210514164344-f6687ab2804c // indirect
-	golang.org/x/text v0.4.0 // indirect
-	golang.org/x/tools v0.1.12 // indirect
+	golang.org/x/text v0.13.0 // indirect
+	golang.org/x/tools v0.6.0 // indirect
 	google.golang.org/api v0.47.0 // indirect
 	google.golang.org/appengine v1.6.7 // indirect
 	google.golang.org/genproto v0.0.0-20210602131652-f16073e35f0c // indirect

go.sum

@@ -349,6 +349,8 @@ github.com/frankban/quicktest v1.11.3/go.mod h1:wRf/ReqHper53s+kmmSZizM8NamnL3IM
 github.com/fsnotify/fsnotify v1.4.7/go.mod h1:jwhsz4b93w/PPRr/qN1Yymfu8t87LnFCMoQvtojpjFo=
 github.com/fsnotify/fsnotify v1.4.9/go.mod h1:znqG4EE+3YCdAaPaxE2ZRY/06pZUdp0tY4IgpuI1SZQ=
 github.com/fullsailor/pkcs7 v0.0.0-20190404230743-d7302db945fa/go.mod h1:KnogPXtdwXqoenmZCw6S+25EAm2MkxbG0deNDu4cbSA=
+github.com/gabriel-vasile/mimetype v1.4.3 h1:in2uUcidCuFcDKtdcBxlR0rJ1+fsokWf+uqxgUFjbI0=
+github.com/gabriel-vasile/mimetype v1.4.3/go.mod h1:d8uq/6HKRL6CGdk+aubisF/M5GcPfT7nKyLpA0lbSSk=
 github.com/garyburd/redigo v0.0.0-20150301180006-535138d7bcd7/go.mod h1:NR3MbYisc3/PwhQ00EMzDiPmrwpPxAn5GI05/YaO1SY=
 github.com/ghodss/yaml v0.0.0-20150909031657-73d445a93680/go.mod h1:4dBDuWmgqj2HViK6kFavaiC9ZROes6MMH2rRYeMEF04=
 github.com/ghodss/yaml v1.0.0/go.mod h1:4dBDuWmgqj2HViK6kFavaiC9ZROes6MMH2rRYeMEF04=
@@ -944,8 +946,9 @@ golang.org/x/crypto v0.0.0-20201002170205-7f63de1d35b0/go.mod h1:LzIPMQfyMNhhGPh
 golang.org/x/crypto v0.0.0-20210322153248-0c34fe9e7dc2/go.mod h1:T9bdIzuCu7OtxOm1hfPfRQxPLYneinmdGuTeoZ9dtd4=
 golang.org/x/crypto v0.0.0-20210513164829-c07d793c2f9a/go.mod h1:P+XmwS30IXTQdn5tA2iutPOUgjI07+tq3H3K9MVA1s8=
 golang.org/x/crypto v0.0.0-20210921155107-089bfa567519/go.mod h1:GvvjBRRGRdwPK5ydBHafDWAxML/pGHZbMvKqRZ5+Abc=
-golang.org/x/crypto v0.3.0 h1:a06MkbcxBrEFc0w0QIZWXrH/9cCX6KJyWbBOIwAn+7A=
 golang.org/x/crypto v0.3.0/go.mod h1:hebNnKkNXi2UzZN1eVRvBB7co0a+JxK6XbPiWVs/3J4=
+golang.org/x/crypto v0.14.0 h1:wBqGXzWJW6m1XrIKlAH0Hs1JJ7+9KBwnIO8v66Q9cHc=
+golang.org/x/crypto v0.14.0/go.mod h1:MVFd36DqK4CsrnJYDkBA3VC4m2GkXAM0PvzMCn4JQf4=
 golang.org/x/exp v0.0.0-20190121172915-509febef88a4/go.mod h1:CJ0aWSM057203Lf6IL+f9T1iT9GByDxfZKAQTCR3kQA=
 golang.org/x/exp v0.0.0-20190306152737-a1d7652674e8/go.mod h1:CJ0aWSM057203Lf6IL+f9T1iT9GByDxfZKAQTCR3kQA=
 golang.org/x/exp v0.0.0-20190510132918-efd6b22b2522/go.mod h1:ZjyILWgesfNpC6sMxTJOJm9Kp84zZh5NQWvqDGG3Qr8=
@@ -982,8 +985,9 @@ golang.org/x/mod v0.3.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/mod v0.4.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/mod v0.4.1/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/mod v0.4.2/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
-golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4 h1:6zppjxzCulZykYSLyVDYbneBfbaBIQPYMevg0bEwv2s=
 golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4/go.mod h1:jJ57K6gSWd91VN4djpZkiMVwK6gcyfeH4XE8wZrZaV4=
+golang.org/x/mod v0.8.0 h1:LUYupSeNrTNCGzR/hVBk2NHZO4hXcVaW1k4Qx7rjPx8=
+golang.org/x/mod v0.8.0/go.mod h1:iBbtSCu2XBx23ZKBPSOrRkjjQPZFPuis4dIYUhu/chs=
 golang.org/x/net v0.0.0-20180724234803-3673e40ba225/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
 golang.org/x/net v0.0.0-20180811021610-c39426892332/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
 golang.org/x/net v0.0.0-20180826012351-8a410e7b638d/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
@@ -1038,8 +1042,9 @@ golang.org/x/net v0.0.0-20210503060351-7fd8e65b6420/go.mod h1:9nx3DQGgdP8bBQD5qx
 golang.org/x/net v0.0.0-20210525063256-abc453219eb5/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
 golang.org/x/net v0.0.0-20210614182718-04defd469f4e/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
 golang.org/x/net v0.0.0-20220722155237-a158d28d115b/go.mod h1:XRhObCWvk6IyKnWLug+ECip1KBveYUHfp+8e9klMJ9c=
-golang.org/x/net v0.2.0 h1:sZfSu1wtKLGlWI4ZZayP0ck9Y73K1ynO6gqzTdBVdPU=
 golang.org/x/net v0.2.0/go.mod h1:KqCZLdyyvdV855qA2rE3GC2aiw5xGR5TEjj8smXukLY=
+golang.org/x/net v0.17.0 h1:pVaXccu2ozPjCXewfr1S7xza/zcXTity9cCdXQYSjIM=
+golang.org/x/net v0.17.0/go.mod h1:NxSsAGuq816PNPmqtQdLE42eU2Fs7NoRIZrHJAlaCOE=
 golang.org/x/oauth2 v0.0.0-20180821212333-d2e6202438be/go.mod h1:N/0e6XlmueqKjAGxoOufVs8QHGRruUQn6yWY3a++T0U=
 golang.org/x/oauth2 v0.0.0-20190226205417-e64efc72b421/go.mod h1:gOpvHmFTYa4IltrdGE7lF6nIHvwfUNPOp7c8zoXwtLw=
 golang.org/x/oauth2 v0.0.0-20190604053449-0f29369cfe45/go.mod h1:gOpvHmFTYa4IltrdGE7lF6nIHvwfUNPOp7c8zoXwtLw=
@@ -1066,6 +1071,7 @@ golang.org/x/sync v0.0.0-20201020160332-67f06af15bc9/go.mod h1:RxMgew5VJxzue5/jJ
 golang.org/x/sync v0.0.0-20201207232520-09787c993a3a/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20210220032951-036812b2e83c/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20220722155255-886fb9371eb4/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sync v0.1.0 h1:wsuoTGHzEhffawBOhz5CYhcrV4IdKZbEyZjBMuTp12o=
 golang.org/x/sys v0.0.0-20180823144017-11551d06cbcc/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20180830151530-49385e6e1522/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20180905080454-ebe1bf3edb33/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
@@ -1157,16 +1163,18 @@ golang.org/x/sys v0.0.0-20220319134239-a9b59b0215f8/go.mod h1:oPkhp1MJrh7nUepCBc
 golang.org/x/sys v0.0.0-20220517195934-5e4e11fc645e/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20220520151302-bc2c85ada10a/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20220722155257-8c9f86f7a55f/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.2.0 h1:ljd4t30dBnAvMZaQCevtY0xLLD0A+bRZXbgLMLU1F/A=
 golang.org/x/sys v0.2.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.13.0 h1:Af8nKPmuFypiUBjVoU9V20FiaFXOcuZI21p0ycVYYGE=
+golang.org/x/sys v0.13.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
 golang.org/x/term v0.0.0-20210220032956-6a3ed077a48d/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
 golang.org/x/term v0.0.0-20210317153231-de623e64d2a6/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
 golang.org/x/term v0.0.0-20210503060354-a79de5458b56/go.mod h1:tfny5GFUkzUvx4ps4ajbZsCe5lw1metzhBm9T3x7oIY=
 golang.org/x/term v0.0.0-20210615171337-6886f2dfbf5b/go.mod h1:jbD1KX2456YbFQfuXm/mYQcufACuNUgVhRMnK/tPxf8=
 golang.org/x/term v0.0.0-20210927222741-03fcf44c2211/go.mod h1:jbD1KX2456YbFQfuXm/mYQcufACuNUgVhRMnK/tPxf8=
-golang.org/x/term v0.2.0 h1:z85xZCsEl7bi/KwbNADeBYoOP0++7W1ipu+aGnpwzRM=
 golang.org/x/term v0.2.0/go.mod h1:TVmDHMZPmdnySmBfhjOoOdhjzdE1h4u1VwSiw2l1Nuc=
+golang.org/x/term v0.13.0 h1:bb+I9cTfFazGW51MZqBVmZy7+JEJMouUHTUSKVQLBek=
+golang.org/x/term v0.13.0/go.mod h1:LTmsnFJwVN6bCy1rVCoS+qHT1HhALEFxKncY3WNNh4U=
 golang.org/x/text v0.0.0-20170915032832-14c0d48ead0c/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.1-0.20180807135948-17ff2d5776d2/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
@@ -1176,8 +1184,9 @@ golang.org/x/text v0.3.4/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/text v0.3.5/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/text v0.3.6/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/text v0.3.7/go.mod h1:u+2+/6zg+i71rQMx5EYifcz6MCKuco9NR6JIITiCfzQ=
-golang.org/x/text v0.4.0 h1:BrVqGRd7+k1DiOgtnFvAkoQEWQvBc25ouMJM6429SFg=
 golang.org/x/text v0.4.0/go.mod h1:mrYo+phRRbMaCq/xk9113O4dZlRixOauAjOtrjsXDZ8=
+golang.org/x/text v0.13.0 h1:ablQoSUd0tRdKxZewP80B+BaqeKJuVhuRxj/dkrun3k=
+golang.org/x/text v0.13.0/go.mod h1:TvPlkZtksWOMsz7fbANvkp4WM8x/WCo/om8BMLbz+aE=
 golang.org/x/time v0.0.0-20180412165947-fbb02b2291d2/go.mod h1:tRJNPiyCQ0inRvYxbN9jk5I+vvW/OXSQhTDSoE431IQ=
 golang.org/x/time v0.0.0-20181108054448-85acf8d2951c/go.mod h1:tRJNPiyCQ0inRvYxbN9jk5I+vvW/OXSQhTDSoE431IQ=
 golang.org/x/time v0.0.0-20190308202827-9d24e82272b4/go.mod h1:tRJNPiyCQ0inRvYxbN9jk5I+vvW/OXSQhTDSoE431IQ=
@@ -1240,8 +1249,9 @@ golang.org/x/tools v0.0.0-20210106214847-113979e3529a/go.mod h1:emZCQorbCU4vsT4f
 golang.org/x/tools v0.1.0/go.mod h1:xkSsbof2nBLbhDlRMhhhyNLN/zl3eTqcnHD5viDpcZ0=
 golang.org/x/tools v0.1.1/go.mod h1:o0xws9oXOQQZyjljx8fwUC0k7L1pTE6eaCbjGeHmOkk=
 golang.org/x/tools v0.1.2/go.mod h1:o0xws9oXOQQZyjljx8fwUC0k7L1pTE6eaCbjGeHmOkk=
-golang.org/x/tools v0.1.12 h1:VveCTK38A2rkS8ZqFY25HIDFscX5X9OoEhJd3quQmXU=
 golang.org/x/tools v0.1.12/go.mod h1:hNGJHUnrk76NpqgfD5Aqm5Crs+Hm0VOH/i9J2+nxYbc=
+golang.org/x/tools v0.6.0 h1:BOw41kyTf3PuCW1pVQf8+Cyg8pMlkYB1oo9iJ6D/lKM=
+golang.org/x/tools v0.6.0/go.mod h1:Xwgl3UAJ/d3gWutnCtw505GrjyAbvKui8lOU390QaIU=
 golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=

test-fixtures/util-test/is-text-file/file-go.go

@@ -0,0 +1 @@
+package is_text_file

test-fixtures/util-test/is-text-file/file-hcl.hcl

@@ -0,0 +1,8 @@
+terraform {
+  source = "."
+}
+
+inputs = {
+  region = "us-west-2"
+  vpc_cidr = "10.0.0.1/"
+}

test-fixtures/util-test/is-text-file/file-java.java

@@ -0,0 +1,5 @@
+package test
+
+public static void main(String... args) {
+
+}

test-fixtures/util-test/is-text-file/file-xml.xml

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="UTF-8" ?>
+<tomato>
+    <potato>potato</potato>
+</tomato>

util/file.go

@@ -2,18 +2,15 @@ package util
 
 import (
 	"fmt"
-	"io"
+	"github.com/gabriel-vasile/mimetype"
+	"github.com/gruntwork-io/boilerplate/errors"
 	"io/ioutil"
-	"net/http"
 	"os"
 	"os/exec"
 	"path/filepath"
-	"strings"
-
-	"github.com/gruntwork-io/boilerplate/errors"
 )
 
-var textMimeTypePrefixes = []string{"text", "application/json"}
+const textMimeType = "text/plain"
 
 // Return true if the path exists
 func PathExists(path string) bool {
@@ -27,67 +24,30 @@ func IsDir(path string) bool {
 	return err == nil && fileInfo.IsDir()
 }
 
-// There is no way to know for sure if a file is text or binary. The best we can do is use various heuristics to guess.
-// The best set of heuristics is in the Unix/Linux file command, so we use that if it's available. Otherwise, we turn
-// to Go's HTTP package. For more info, see: http://stackoverflow.com/q/16760378/483528
+// IsTextFile - usage of mimetype library to identify if the file is binary or text.
 func IsTextFile(path string) (bool, error) {
-	mimeType, err := GuessMimeType(path)
-	if err != nil {
-		return false, err
+	if !PathExists(path) {
+		return false, NoSuchFile(path)
 	}
-	for _, prefix := range textMimeTypePrefixes {
-		if strings.HasPrefix(mimeType, prefix) {
-			return true, nil
-		}
+	// consider empty file as binary file
+	fileInfo, err := os.Stat(path)
+	if err != nil {
+		return false, errors.WithStackTrace(err)
 	}
-	return false, nil
-}
-
-// Guess the mime type for the given file using a variety of heuristics. Under the hood, uses the Unix/Linux file
-// command, if available, and Go's HTTP package otherwise.
-func GuessMimeType(path string) (string, error) {
-	if PathExists(path) {
-		if CommandInstalled("file") {
-			return guessMimeTypeUsingFileCommand(path)
-		} else {
-			return guessMimeTypeUsingGoHttpPackage(path)
-		}
-	} else {
-		return "", errors.WithStackTrace(NoSuchFile(path))
+	if fileInfo.Size() == 0 {
+		return false, nil
 	}
-}
-
-// Use the Unix/Linux "file" command to determine the mime type. This performs a number of checks and tends to do a
-// good job with most files.
-func guessMimeTypeUsingFileCommand(path string) (string, error) {
-	return RunCommandAndGetOutput("file", "-b", "--mime", path)
-}
 
-// Use a package built into Go for detecting the mime type of arbitrary content. In my experience, it doesn't work
-// very well.
-func guessMimeTypeUsingGoHttpPackage(path string) (string, error) {
-	file, err := os.Open(path)
+	detectedMIME, err := mimetype.DetectFile(path)
 	if err != nil {
-		return "", errors.WithStackTrace(err)
-	}
-	defer file.Close()
-
-	first512Bytes := make([]byte, 512)
-	numBytesRead, err := file.Read(first512Bytes)
-	if err != nil && err != io.EOF {
-		return "", errors.WithStackTrace(err)
+		return false, errors.WithStackTrace(err)
 	}
-
-	// If it's an empty file, there is no real distinction, so default to "false", as there is not much processing
-	// you can do on an empty file anyway
-	if numBytesRead == 0 {
-		return "", nil
+	for mtype := detectedMIME; mtype != nil; mtype = mtype.Parent() {
+		if mtype.Is(textMimeType) {
+			return true, nil
+		}
 	}
-
-	// skip null values from read array
-	first512Bytes = first512Bytes[:numBytesRead]
-
-	return http.DetectContentType(first512Bytes), nil
+	return false, nil
 }
 
 // Return true if the OS has the given command installed

util/file_test.go

@@ -30,13 +30,21 @@ func TestIsTextFile(t *testing.T) {
 		{"text-file.tf", true},
 		{"json-file.json", true},
 		{"yaml-file.yaml", true},
+		{"file-go.go", true},
+		{"file-java.java", true},
+		{"file-xml.xml", true},
+		{"file-hcl.hcl", true},
 	}
 
 	for _, testCase := range testCases {
-		actual, err := IsTextFile(fmt.Sprintf("../test-fixtures/util-test/is-text-file/%s", testCase.file))
-
-		assert.Nil(t, err)
-		assert.Equal(t, testCase.isText, actual, "Incorrect classification for %s", testCase.file)
+		testCase := testCase
+		t.Run(testCase.file, func(t *testing.T) {
+			t.Parallel()
+			actual, err := IsTextFile(fmt.Sprintf("../test-fixtures/util-test/is-text-file/%s", testCase.file))
+
+			assert.Nil(t, err)
+			assert.Equal(t, testCase.isText, actual, "Incorrect classification for %s", testCase.file)
+		})
 	}
 }