Merge branch 'njones-template-timefmt'

packer/config_template.go

@@ -113,8 +113,16 @@ func templateEnv(n string) string {
 	return os.Getenv(n)
 }
 
-func templateISOTime() string {
-	return InitTime.Format(time.RFC3339)
+func templateISOTime(timeFormat ...string) (string, error) {
+	if len(timeFormat) == 0 {
+		return time.Now().UTC().Format(time.RFC3339), nil
+	}
+
+	if len(timeFormat) > 1 {
+		return "", fmt.Errorf("too many values, 1 needed: %v", timeFormat)
+	}
+
+	return time.Now().UTC().Format(timeFormat[0]), nil
 }
 
 func templatePwd() (string, error) {

packer/config_template_test.go

 package packer
 
 import (
+	"fmt"
 	"math"
 	"os"
 	"strconv"
@@ -42,6 +43,33 @@ func TestConfigTemplateProcess_isotime(t *testing.T) {
 	}
 }
 
+// Note must format with the magic Date: Mon Jan 2 15:04:05 -0700 MST 2006
+func TestConfigTemplateProcess_isotime_withFormat(t *testing.T) {
+	tpl, err := NewConfigTemplate()
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	// Checking for a too-many arguments error
+	// Because of the variadic function, compile time checking won't work
+	_, err = tpl.Process(`{{isotime "20060102" "huh"}}`, nil)
+	if err == nil {
+		t.Fatalf("err: cannot have more than 1 input")
+	}
+	
+	result, err := tpl.Process(`{{isotime "20060102"}}`, nil)
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	
+	ti := time.Now().UTC() 
+	val := fmt.Sprintf("%04d%02d%02d", ti.Year(), ti.Month(), ti.Day()) 
+
+	if result != val {
+		t.Fatalf("val: %s (formated: %s)", val, result)
+	}
+}
+
 func TestConfigTemplateProcess_pwd(t *testing.T) {
 	tpl, err := NewConfigTemplate()
 	if err != nil {

website/source/docs/templates/configuration-templates.html.markdown

@@ -53,13 +53,68 @@ While some configuration settings have local variables specific to only that
 configuration, a set of functions are available globally for use in _any string_
 in Packer templates. These are listed below for reference.
 
-* `isotime` - UTC time in RFC-3339 format.
 * `lower` - Lowercases the string.
 * `pwd` - The working directory while executing Packer.
+* `isotime [FORMAT]` - UTC time, which can be [formatted](http://golang.org/pkg/time/#example_Time_Format).
+   See more examples below.
 * `timestamp` - The current Unix timestamp in UTC.
 * `uuid` - Returns a random UUID.
 * `upper` - Uppercases the string.
 
+### isotime Format
+
+Formatting for the function `isotime` uses the magic reference date
+**Mon Jan 2 15:04:05 -0700 MST 2006**, which breaks down to the following:
+
+ <table border="1" cellpadding="5" width="100%">
+ 	<tr bgcolor="lightgray">
+ 		<td></td>
+ 		<td align="center"><strong>Day of Week</strong></td>
+ 		<td align="center"><strong>Month</strong></td>
+ 		<td align="center"><strong>Date</strong></td>
+ 		<td align="center"><strong>Hour</strong></td>
+ 		<td align="center"><strong>Minute</strong></td>
+ 		<td align="center"><strong>Second</strong></td>
+ 		<td align="center"><strong>Year</strong></td>
+ 		<td align="center"><strong>Timezone</strong></td>
+ 	</tr>
+ 	<tr>
+ 		<td><strong>Numeric</strong></td>
+ 		<td align="center">-</td>
+ 		<td align="center">01</td>
+ 		<td align="center">02</td>
+ 		<td align="center">03 (15)</td>
+ 		<td align="center">04</td>
+ 		<td align="center">05</td>
+ 		<td align="center">06</td>
+ 		<td align="center">-0700</td>
+ 	</tr>
+ 	<tr>
+ 		<td><strong>Textual</strong></td>
+ 		<td align="center">Monday (Mon)</td>
+ 		<td align="center">January (Jan)</td>
+ 		<td align="center">-</td>
+ 		<td align="center">-</td>
+ 		<td align="center">-</td>
+ 		<td align="center">-</td>
+ 		<td align="center">-</td>
+ 		<td align="center">MST</td>
+ 	</tr>
+ </table>
+
+ _The values in parentheses are the abbreviated, or 24-hour clock values_
+
+ Here are some example formated time, using the above format options:
+
+ <pre>
+isotime = June 7, 7:22:43pm 2014
+
+{{isotime "2006-01-02"}} = 2014-06-07
+{{isotime "Mon 1506"}} = Sat 1914
+{{isotime "01-Jan-06 03\_04\_05"}} = 07-Jun-2014 07\_22\_43
+{{isotime "Hour15Year200603"}} = Hour19Year201407
+</pre>
+
 ## Amazon Specific Functions
 
 Specific to Amazon builders: