From 36365c68fb7dc9f5cab3b6b480e8d2c145650583 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Mickae=CC=88l=20Menu?= <mickael.menu@gmail.com>
Date: Thu, 11 Mar 2021 21:18:29 +0100
Subject: [PATCH] Expose environment variables to note templates with the new
 {{env}} variable

---
 CHANGELOG.md              |  1 +
 core/note/create.go       |  3 +++
 core/note/create_test.go  |  6 ++++++
 core/note/format.go       |  1 +
 docs/template-creation.md |  1 +
 util/os/os.go             | 11 +++++++++++
 6 files changed, 23 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index cd64a7c..e6f3fa9 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -13,6 +13,7 @@ All notable changes to this project will be documented in this file.
         * Use glob patterns to match multiple tags, e.g. `--tag "book-*"`.
     * Many tag flavors are supported: `#hashtags`, `:colon:separated:tags:` ([opt-in](docs/note-format.md)) and even Bear's [`#multi-word tags#`](https://blog.bear.app/2017/11/bear-tips-how-to-create-multi-word-tags/) ([opt-in](docs/note-format.md)). If you prefer to use a YAML frontmatter, list your tags with the key `tags` or `keywords`.
 * Print metadata from the YAML frontmatter in `list` output using `{{metadata.<key>}}`, e.g. `{{metadata.description}}`. Keys are normalized to lower case.
+* Access environment variables from note templates with the `env.<key>` template variable, e.g. `{{env.PATH}}`.
 
 ### Changed
 
diff --git a/core/note/create.go b/core/note/create.go
index dbf746e..2d7e4bf 100644
--- a/core/note/create.go
+++ b/core/note/create.go
@@ -10,6 +10,7 @@ import (
 	"github.com/mickael-menu/zk/util/date"
 	"github.com/mickael-menu/zk/util/errors"
 	"github.com/mickael-menu/zk/util/opt"
+	"github.com/mickael-menu/zk/util/os"
 	"github.com/mickael-menu/zk/util/paths"
 	"github.com/mickael-menu/zk/util/rand"
 )
@@ -96,6 +97,7 @@ type renderContext struct {
 	FilenameStem string `handlebars:"filename-stem"`
 	Extra        map[string]string
 	Now          time.Time
+	Env          map[string]string
 }
 
 type createDeps struct {
@@ -116,6 +118,7 @@ func create(
 		Dir:     opts.Dir.Name,
 		Extra:   opts.Dir.Config.Extra,
 		Now:     deps.now,
+		Env:     os.Env(),
 	}
 
 	path, context, err := genPath(context, opts.Dir, deps)
diff --git a/core/note/create_test.go b/core/note/create_test.go
index 7bf3f49..49e1acd 100644
--- a/core/note/create_test.go
+++ b/core/note/create_test.go
@@ -7,6 +7,7 @@ import (
 	"github.com/mickael-menu/zk/core/templ"
 	"github.com/mickael-menu/zk/core/zk"
 	"github.com/mickael-menu/zk/util/opt"
+	"github.com/mickael-menu/zk/util/os"
 	"github.com/mickael-menu/zk/util/test/assert"
 )
 
@@ -57,6 +58,7 @@ func TestCreate(t *testing.T) {
 			"hello": "world",
 		},
 		Now: Now,
+		Env: os.Env(),
 	}})
 	assert.Equal(t, bodyTemplate.Contexts, []interface{}{renderContext{
 		ID:           "abc",
@@ -69,6 +71,7 @@ func TestCreate(t *testing.T) {
 			"hello": "world",
 		},
 		Now: Now,
+		Env: os.Env(),
 	}})
 }
 
@@ -115,18 +118,21 @@ func TestCreateTriesUntilValidPath(t *testing.T) {
 			Title: "Note title",
 			Dir:   "log",
 			Now:   Now,
+			Env:   os.Env(),
 		},
 		renderContext{
 			ID:    "2",
 			Title: "Note title",
 			Dir:   "log",
 			Now:   Now,
+			Env:   os.Env(),
 		},
 		renderContext{
 			ID:    "3",
 			Title: "Note title",
 			Dir:   "log",
 			Now:   Now,
+			Env:   os.Env(),
 		},
 	})
 }
diff --git a/core/note/format.go b/core/note/format.go
index c94a738..56c07fb 100644
--- a/core/note/format.go
+++ b/core/note/format.go
@@ -128,4 +128,5 @@ type formatRenderContext struct {
 	Created    time.Time
 	Modified   time.Time
 	Checksum   string
+	Env        map[string]string
 }
diff --git a/docs/template-creation.md b/docs/template-creation.md
index 1ad24d1..7bf74c5 100644
--- a/docs/template-creation.md
+++ b/docs/template-creation.md
@@ -10,6 +10,7 @@ The following variables are available in the templates used when [creating new n
 | `dir`         | string | Parent directory in the notebook                                                      |
 | `extra.<key>` | string | [Additional variables](config-extra.md) provided through the config file or `--extra` |
 | `now`         | date   | Current date and time, useful when paired with [`{{date now}}`](template.md)          |
+| `env`         | map    | Dictionary of case-sensitive environment variables, e.g. `{{env.PATH}}`.              |
 
 These additional variables are available only to the note content template, once the filename is generated.
 
diff --git a/util/os/os.go b/util/os/os.go
index dcce62d..fb9a0c5 100644
--- a/util/os/os.go
+++ b/util/os/os.go
@@ -4,6 +4,7 @@ import (
 	"bufio"
 	"io/ioutil"
 	"os"
+	"strings"
 
 	"github.com/mickael-menu/zk/util/opt"
 )
@@ -33,3 +34,13 @@ func ReadStdinPipe() (opt.String, error) {
 func GetOptEnv(key string) opt.String {
 	return opt.NewNotEmptyString(os.Getenv(key))
 }
+
+// Env returns a map of environment variables.
+func Env() map[string]string {
+	env := map[string]string{}
+	for _, e := range os.Environ() {
+		pair := strings.SplitN(e, "=", 2)
+		env[pair[0]] = pair[1]
+	}
+	return env
+}