feat: add envPrefix nested env vars lists

_examples/README.md

@@ -12,7 +12,7 @@ There are few target files:
   [`x_complex.md`](./x_complex.md) with `-env-prefix` argument;
   and [`complex-nostyle.html`](./complex-nostyle.html) which is HTML documentation without built-in styles.
 - [`envprefix.go`](./envprefix.go) showcases a nested config structure with the `envPrefix` tag for a structure field.
-  It generates [`envprefix.md`](./envprefix.md).
+  It generates [`envprefix.md`](./envprefix.md), [`envprefix.txt`](./envprefix.txt) and [`envprefix.html`](./envprefix.html).
 
 The examples directory also contains helper script files:
  - `build-examples.sh` - modify any example Go file and regenerate all documentation outputs by executing it via `./build-examples.sh`.

_examples/complex-nostyle.html

@@ -23,21 +23,18 @@ <h2>ComplexConfig</h2>
     <li><code>HOSTS</code> (separated by "<code>:</code>", <strong>required</strong>) - Hosts is a list of hosts.</li>
     <li><code>WORDS</code> (comma-separated, from-file, default: <code>one,two,three</code>) - Words is just a list of words.</li>
     <li><code>COMMENT</code> (<strong>required</strong>, default: <code>This is a comment.</code>) - Just a comment.</li>
-
   </ul>
 
   <h2>NextConfig</h2>
 
   <ul>
     <li><code>MOUNT</code> (<strong>required</strong>) - Mount is a mount point.</li>
-
   </ul>
 
   <h2>FieldNames</h2>
 <p>FieldNames uses field names as env names.</p>
   <ul>
     <li><code>QUUX</code> - Quux is a field with a tag.</li>
-
   </ul>
 
       </article>

_examples/complex.html

@@ -89,21 +89,18 @@ <h2>ComplexConfig</h2>
     <li><code>HOSTS</code> (separated by "<code>:</code>", <strong>required</strong>) - Hosts is a list of hosts.</li>
     <li><code>WORDS</code> (comma-separated, from-file, default: <code>one,two,three</code>) - Words is just a list of words.</li>
     <li><code>COMMENT</code> (<strong>required</strong>, default: <code>This is a comment.</code>) - Just a comment.</li>
-
   </ul>
 
   <h2>NextConfig</h2>
 
   <ul>
     <li><code>MOUNT</code> (<strong>required</strong>) - Mount is a mount point.</li>
-
   </ul>
 
   <h2>FieldNames</h2>
 <p>FieldNames uses field names as env names.</p>
   <ul>
     <li><code>QUUX</code> - Quux is a field with a tag.</li>
-
   </ul>
 
       </article>

_examples/config.html

@@ -84,7 +84,6 @@ <h2>Config</h2>
     <li><code>HOST</code> (separated by "<code>;</code>", <strong>required</strong>) - Hosts name of hosts to listen on.</li>
     <li><code>PORT</code> (<strong>required</strong>, non-empty) - Port to listen on.</li>
     <li><code>DEBUG</code> (default: <code>false</code>) - Debug mode enabled.</li>
-
   </ul>
 
       </article>

_examples/envprefix.go

@@ -1,15 +1,51 @@
 package main
 
+// Settings is the application settings.
+//
+//go:generate go run ../ -output envprefix.txt -format plaintext -type Settings
 //go:generate go run ../ -output envprefix.md -type Settings
+//go:generate go run ../ -output envprefix.html -format html -type Settings
 type Settings struct {
 	// Database is the database settings
 	Database Database `envPrefix:"DB_"`
 
+	// Server is the server settings
+	Server ServerConfig `envPrefix:"SERVER_"`
+
 	// Debug is the debug flag
 	Debug bool `env:"DEBUG"`
 }
 
+// Database is the database settings.
 type Database struct {
 	// Port is the port to connect to
 	Port Int `env:"PORT,required"`
+	// Host is the host to connect to
+	Host string `env:"HOST,notEmpty" envDefault:"localhost"`
+	// User is the user to connect as
+	User string `env:"USER"`
+	// Password is the password to use
+	Password string `env:"PASSWORD"`
+	// DisableTLS is the flag to disable TLS
+	DisableTLS bool `env:"DISABLE_TLS"`
+}
+
+// ServerConfig is the server settings.
+type ServerConfig struct {
+	// Port is the port to listen on
+	Port Int `env:"PORT,required"`
+
+	// Host is the host to listen on
+	Host string `env:"HOST,notEmpty" envDefault:"localhost"`
+
+	// Timeout is the timeout settings
+	Timeout TimeoutConfig `envPrefix:"TIMEOUT_"`
+}
+
+// TimeoutConfig is the timeout settings.
+type TimeoutConfig struct {
+	// Read is the read timeout
+	Read Int `env:"READ" envDefault:"30"`
+	// Write is the write timeout
+	Write Int `env:"WRITE" envDefault:"30"`
 }

_examples/envprefix.html

@@ -0,0 +1,109 @@
+<!DOCTYPE html>
+<html lang="en">
+    <head>
+    <meta charset="utf-8">
+    <title>Environment Variables</title>
+<style>
+* {
+  box-sizing: border-box;
+}
+body {
+  font-family: sans-serif;
+  color: #1F2328;
+}
+article {
+  margin-left: auto;
+  margin-right: auto;
+  max-width: 1012px;
+  font-size: 16px;
+  line-height: 1.5;
+  word-wrap: break-word;
+  display: block;
+  padding: 32px;
+}
+article::first-child {
+  margin-top: 0 !important;
+}
+article::last-child {
+  margin-bottom: 0 !important;
+}
+section {
+  margin-top: 46px;
+  background-color: #ffffff;
+  border: 0px;
+  border-radius: 0px 0px 6px 6px;
+  padding: 0px;
+  min-width: 0px;
+  margin-top: 46px;
+  -moz-box-pack: center;
+}
+h1, h2 {
+  margin-top: 24px;
+  margin-bottom: 16px;
+  line-height: 1.25;
+  font-weight: 600;
+  padding-bottom: .3em;
+  border-bottom: 1px solid hsla(210,18%,87%,1);
+}
+h1 {
+  font-size: 2em;
+}
+h2 {
+  font-size: 1.5em;
+}
+li {
+  margin-top: .25em;
+}
+li code {
+  padding: .2em .4em;
+  margin: 0;
+  font-size: 85%;
+  white-space: break-sp#ffffffaces;
+  background-color: rgba(175,184,193,0.2);
+  border-radius: 6px;
+}
+li strong {
+    font-weight: 600;
+}
+p {
+  margin-top: 0;
+  margin-bottom: 16px;
+}
+    </style>
+  </head>
+  <body>
+    <section>
+      <article>
+        <h1>Environment Variables</h1>
+
+  <h2>Settings</h2>
+<p>Settings is the application settings.</p>
+  <ul>
+    <li>Database is the database settings.
+    <ul>
+    <li><code>DB_PORT</code> (<strong>required</strong>) - Port is the port to connect to</li>
+    <li><code>DB_HOST</code> (<strong>required</strong>, non-empty, default: <code>localhost</code>) - Host is the host to connect to</li>
+    <li><code>DB_USER</code> - User is the user to connect as</li>
+    <li><code>DB_PASSWORD</code> - Password is the password to use</li>
+    <li><code>DB_DISABLE_TLS</code> - DisableTLS is the flag to disable TLS</li>
+    </ul>
+  </li>
+    <li>ServerConfig is the server settings.
+    <ul>
+    <li><code>SERVER_PORT</code> (<strong>required</strong>) - Port is the port to listen on</li>
+    <li><code>SERVER_HOST</code> (<strong>required</strong>, non-empty, default: <code>localhost</code>) - Host is the host to listen on</li>
+    <li>TimeoutConfig is the timeout settings.
+    <ul>
+    <li><code>SERVER_TIMEOUT_READ</code> (default: <code>30</code>) - Read is the read timeout</li>
+    <li><code>SERVER_TIMEOUT_WRITE</code> (default: <code>30</code>) - Write is the write timeout</li>
+    </ul>
+  </li>
+    </ul>
+  </li>
+    <li><code>DEBUG</code> - Debug is the debug flag</li>
+  </ul>
+
+      </article>
+    </section>
+  </body>
+</html>

_examples/envprefix.md

@@ -2,5 +2,18 @@
 
 ## Settings
 
- - `DB_PORT` (**required**) - Port is the port to connect to
+Settings is the application settings.
+
+ - Database is the database settings.
+   - `DB_PORT` (**required**) - Port is the port to connect to
+   - `DB_HOST` (**required**, non-empty, default: `localhost`) - Host is the host to connect to
+   - `DB_USER` - User is the user to connect as
+   - `DB_PASSWORD` - Password is the password to use
+   - `DB_DISABLE_TLS` - DisableTLS is the flag to disable TLS
+ - ServerConfig is the server settings.
+   - `SERVER_PORT` (**required**) - Port is the port to listen on
+   - `SERVER_HOST` (**required**, non-empty, default: `localhost`) - Host is the host to listen on
+   - TimeoutConfig is the timeout settings.
+     - `SERVER_TIMEOUT_READ` (default: `30`) - Read is the read timeout
+     - `SERVER_TIMEOUT_WRITE` (default: `30`) - Write is the write timeout
  - `DEBUG` - Debug is the debug flag

_examples/envprefix.txt

@@ -0,0 +1,19 @@
+Environment Variables
+
+## Settings
+
+Settings is the application settings.
+
+ * Database is the database settings.
+   * `DB_PORT` (required) - Port is the port to connect to
+   * `DB_HOST` (required, non-empty, default: `localhost`) - Host is the host to connect to
+   * `DB_USER` - User is the user to connect as
+   * `DB_PASSWORD` - Password is the password to use
+   * `DB_DISABLE_TLS` - DisableTLS is the flag to disable TLS
+ * ServerConfig is the server settings.
+   * `SERVER_PORT` (required) - Port is the port to listen on
+   * `SERVER_HOST` (required, non-empty, default: `localhost`) - Host is the host to listen on
+   * TimeoutConfig is the timeout settings.
+     * `SERVER_TIMEOUT_READ` (default: `30`) - Read is the read timeout
+     * `SERVER_TIMEOUT_WRITE` (default: `30`) - Write is the write timeout
+ * `DEBUG` - Debug is the debug flag

debug.go

@@ -0,0 +1,12 @@
+package main
+
+import "fmt"
+
+const debugLogs = false
+
+func debug(f string, args ...any) {
+	if !debugLogs {
+		return
+	}
+	fmt.Printf("DEBUG: "+f+"\n", args...)
+}

inspector.go

@@ -22,6 +22,7 @@ type envField struct {
 	doc       string
 	opts      EnvVarOptions
 	typeRef   string
+	fieldName string
 	envPrefix string
 }
 
@@ -206,6 +207,11 @@ func (i *inspector) parseField(f *ast.Field) (out []envField) {
 		item.kind = envFieldKindStruct
 		fieldType := f.Type.(*ast.Ident)
 		item.typeRef = fieldType.Name
+		fieldNames := make([]string, len(f.Names))
+		for i, name := range f.Names {
+			fieldNames[i] = name.Name
+		}
+		item.fieldName = strings.Join(fieldNames, ", ")
 		out = []envField{item}
 		return
 	}
@@ -229,6 +235,7 @@ func (i *inspector) parseField(f *ast.Field) (out []envField) {
 	} else {
 		return
 	}
+
 	docStr := strings.TrimSpace(f.Doc.Text())
 	if docStr == "" {
 		docStr = strings.TrimSpace(f.Comment.Text())
@@ -288,51 +295,51 @@ func (i *inspector) buildScopes() ([]*EnvScope, error) {
 			Doc:  s.doc,
 		}
 		for _, f := range s.fields {
-			switch f.kind {
-			case envFieldKindPlain:
-				v := EnvDocItem{
-					Name: f.name,
-					Doc:  f.doc,
-					Opts: f.opts,
-				}
-				debug("[p] add docItem: %s <- %s", scope.Name, v.Name)
-				scope.Vars = append(scope.Vars, v)
-			case envFieldKindStruct:
-				envPrefix := f.envPrefix
-				var base *envStruct
-				for _, s := range i.items {
-					if s.name == f.typeRef {
-						base = s
-						break
-					}
-				}
-				if base == nil {
-					return nil, fmt.Errorf("struct %q not found", f.typeRef)
-				}
-				for _, f := range base.fields {
-					name := fmt.Sprintf("%s%s", envPrefix, f.name)
-					v := EnvDocItem{
-						Name: name,
-						Doc:  f.doc,
-						Opts: f.opts,
-					}
-					debug("[s] add docItem: %s <- %s (prefix: %s)", scope.Name, v.Name, envPrefix)
-					scope.Vars = append(scope.Vars, v)
-				}
-			default:
-				panic("unknown field kind")
+			item, err := i.buildItem(&f, "")
+			if err != nil {
+				return nil, err
 			}
+			scope.Vars = append(scope.Vars, item)
 		}
 		scopes = append(scopes, scope)
 	}
 	return scopes, nil
 }
 
-const debugLogs = false
-
-func debug(f string, args ...any) {
-	if !debugLogs {
-		return
+func (i *inspector) buildItem(f *envField, envPrefix string) (EnvDocItem, error) {
+	switch f.kind {
+	case envFieldKindPlain:
+		return EnvDocItem{
+			Name:      fmt.Sprintf("%s%s", envPrefix, f.name),
+			Doc:       f.doc,
+			Opts:      f.opts,
+			debugName: f.name,
+		}, nil
+	case envFieldKindStruct:
+		envPrefix := fmt.Sprintf("%s%s", envPrefix, f.envPrefix)
+		var base *envStruct
+		for _, s := range i.items {
+			if s.name == f.typeRef {
+				base = s
+				break
+			}
+		}
+		if base == nil {
+			return EnvDocItem{}, fmt.Errorf("struct %q not found", f.typeRef)
+		}
+		parentItem := EnvDocItem{
+			Doc:       base.doc,
+			debugName: base.name,
+		}
+		for _, f := range base.fields {
+			item, err := i.buildItem(&f, envPrefix)
+			if err != nil {
+				return EnvDocItem{}, fmt.Errorf("build item `%s`: %w", f.name, err)
+			}
+			parentItem.Children = append(parentItem.Children, item)
+		}
+		return parentItem, nil
+	default:
+		panic("unknown field kind")
 	}
-	fmt.Printf("DEBUG: "+f+"\n", args...)
 }