Add a sha256(...) interpolation function.

config/interpolate_funcs.go

@@ -3,6 +3,7 @@ package config
 import (
  "bytes"
  "crypto/sha1"
+ "crypto/sha256"
  "encoding/base64"
  "encoding/hex"
  "errors"
@@ -39,6 +40,7 @@ func Funcs() map[string]ast.Function {
  "replace": interpolationFuncReplace(),
  "split": interpolationFuncSplit(),
  "sha1": interpolationFuncSha1(),
+ "sha256": interpolationFuncSha256(),
  "base64encode": interpolationFuncBase64Encode(),
  "base64decode": interpolationFuncBase64Decode(),
  "upper": interpolationFuncUpper(),
@@ -601,3 +603,17 @@ func interpolationFuncSha1() ast.Function {
  },
  }
 }
+
+func interpolationFuncSha256() ast.Function {
+ return ast.Function{
+ ArgTypes: []ast.Type{ast.TypeString},
+ ReturnType: ast.TypeString,
+ Callback: func(args []interface{}) (interface{}, error) {
+ s := args[0].(string)
+ h := sha256.New()
+ h.Write([]byte(s))
+ hash := hex.EncodeToString(h.Sum(nil))
+ return hash, nil
+ },
+ }
+}

config/interpolate_funcs_test.go

@@ -846,6 +846,18 @@ func TestInterpolateFuncSha1(t *testing.T) {
  })
 }
 
+func TestInterpolateFuncSha256(t *testing.T) {
+ testFunction(t, testFunctionConfig{
+ Cases: []testFunctionCase{
+ {
+ `${sha256("test")}`,
+ "9f86d081884c7d659a2feaa0c55ad015a3bf4f1b2b0b822cd15d6c15b0f00a08",
+ false,
+ },
+ },
+ })
+}
+
 type testFunctionConfig struct {
  Cases []testFunctionCase
  Vars map[string]ast.Variable

website/source/docs/configuration/interpolation.html.md

@@ -80,10 +80,14 @@ The supported built-in functions are:
  * `base64encode(string)` - Returns a base64-encoded representation of the
  given string.
 
- * `sha1(string)` - Returns a sha1 hash representation of the
+ * `sha1(string)` - Returns a SHA-1 hash representation of the
  given string.
  Example: `"${sha1(concat(aws_vpc.default.tags.customer, "-s3-bucket"))}"`
 
+ * `sha256(string)` - Returns a SHA-256 hash representation of the
+ given string.
+ Example: `"${sha256(concat(aws_vpc.default.tags.customer, "-s3-bucket"))}"`
+
  * `cidrhost(iprange, hostnum)` - Takes an IP address range in CIDR notation
  and creates an IP address with the given host number. For example,
  ``cidrhost("10.0.0.0/8", 2)`` returns ``10.0.0.2``.