tpl: Add sha256 template function

Fixes #2742

diff --git a/docs/content/templates/functions.md b/docs/content/templates/functions.md
index 53252ff6a69f5a02f8e8cf75595e1c0d44792d47..eaeb3cac4ff48662115e3c3ed73447aa64fcfbf8 100644 (file)
--- a/docs/content/templates/functions.md
+++ b/docs/content/templates/functions.md
@@ -768,6 +768,17 @@ This can be useful if you want to use Gravatar for generating a unique avatar:
 <!-- returns the string "c8b5b0e33d408246e30f53e32b8f7627a7a649d4" -->
 ```
 
+
+### sha256
+
+`sha256` hashes the given input and returns its SHA256 checksum.
+
+```html
+{{ sha256 "Hello world, gophers!" }}
+<!-- returns the string "6ec43b78da9669f50e4e422575c54bf87536954ccd58280219c393f2ce352b46" -->
+```
+
+
 ## Internationalization
 
 ### i18n

diff --git a/tpl/template_funcs.go b/tpl/template_funcs.go
index 747641c04cf7be18d230606c7c976678a1f606e7..8f552637864b1b1bd570221e7137898e9259280b 100644 (file)
--- a/tpl/template_funcs.go
+++ b/tpl/template_funcs.go
@@ -19,6 +19,7 @@ import (
        "bytes"
        _md5 "crypto/md5"
        _sha1 "crypto/sha1"
+       _sha256 "crypto/sha256"
        "encoding/base64"
        "encoding/hex"
        "encoding/json"
@@ -1968,6 +1969,17 @@ func sha1(in interface{}) (string, error) {
        return hex.EncodeToString(hash[:]), nil
 }
 
+// sha256 hashes the given input and returns its SHA256 checksum
+func sha256(in interface{}) (string, error) {
+       conv, err := cast.ToStringE(in)
+       if err != nil {
+               return "", err
+       }
+
+       hash := _sha256.Sum256([]byte(conv))
+       return hex.EncodeToString(hash[:]), nil
+}
+
 // querify encodes the given parameters  “URL encoded” form ("bar=baz&foo=quux") sorted by key.
 func querify(params ...interface{}) (string, error) {
        qs := url.Values{}
@@ -2099,6 +2111,7 @@ func initFuncMap() {
                "sanitizeurl":  helpers.SanitizeURL,
                "seq":          helpers.Seq,
                "sha1":         sha1,
+               "sha256":       sha256,
                "shuffle":      shuffle,
                "singularize":  singularize,
                "slice":        slice,

diff --git a/tpl/template_funcs_test.go b/tpl/template_funcs_test.go
index d9cfcbfa3f829bd98f5cad933ff21c6516c0c21c..91e13e3204278d2740d660b213d1ffd489bdb5e3 100644 (file)
--- a/tpl/template_funcs_test.go
+++ b/tpl/template_funcs_test.go
@@ -145,6 +145,7 @@ safeJS: {{ "(1*2)" | safeJS | safeJS }}
 safeURL: {{ "http://gohugo.io" | safeURL | safeURL }}
 seq: {{ seq 3 }}
 sha1: {{ sha1 "Hello world, gophers!" }}
+sha256: {{ sha256 "Hello world, gophers!" }}
 singularize: {{ "cats" | singularize }}
 slicestr: {{slicestr "BatMan" 0 3}}
 slicestr: {{slicestr "BatMan" 3}}
@@ -214,6 +215,7 @@ safeJS: (1*2)
 safeURL: http://gohugo.io
 seq: [1 2 3]
 sha1: c8b5b0e33d408246e30f53e32b8f7627a7a649d4
+sha256: 6ec43b78da9669f50e4e422575c54bf87536954ccd58280219c393f2ce352b46
 singularize: cat
 slicestr: Bat
 slicestr: Man
@@ -2565,6 +2567,30 @@ func TestSHA1(t *testing.T) {
        }
 }
 
+func TestSHA256(t *testing.T) {
+       for i, this := range []struct {
+               input        string
+               expectedHash string
+       }{
+               {"Hello world, gophers!", "6ec43b78da9669f50e4e422575c54bf87536954ccd58280219c393f2ce352b46"},
+               {"Lorem ipsum dolor", "9b3e1beb7053e0f900a674dd1c99aca3355e1275e1b03d3cb1bc977f5154e196"},
+       } {
+               result, err := sha256(this.input)
+               if err != nil {
+                       t.Errorf("sha256 returned error: %s", err)
+               }
+
+               if result != this.expectedHash {
+                       t.Errorf("[%d] sha256: expected '%s', got '%s'", i, this.expectedHash, result)
+               }
+
+               _, err = sha256(t)
+               if err == nil {
+                       t.Error("Expected error from sha256")
+               }
+       }
+}
+
 func TestReadFile(t *testing.T) {
        viper.Reset()
        defer viper.Reset()