external_content/
external_content.rs

1//! External content sources example
2//!
3//! Demonstrates using `FileRef` and `ContentSource` to reference external files
4//! instead of embedding content directly in the archive.
5//!
6//! Run with: cargo run --example `external_content`
7
8use genfile_core::
9{
10  TemplateArchive,
11  FileRef,
12  InlineContent,
13  FileContent,
14  WriteMode,
15  Value,
16  HandlebarsRenderer,
17  MemoryFileSystem,
18  DefaultContentResolver,
19  FileSystem,
20};
21use std::path::PathBuf;
22
23fn main() -> Result< (), Box< dyn core::error::Error > >
24{
25  println!( "=== External Content Sources Example ===" );
26  println!();
27
28  // Create archive
29  let mut archive = TemplateArchive::new( "docs" );
30
31  // Add file with inline content (normal way)
32  archive.add_file_from(
33    PathBuf::from( "inline.txt" ),
34    InlineContent::new( FileContent::Text( "This is inline content".into() ) ),
35    WriteMode::Rewrite
36  );
37
38  // Add file referencing external file
39  archive.add_file_from(
40    PathBuf::from( "external_header.txt" ),
41    FileRef::new( PathBuf::from( "/templates/header.hbs" ) ),
42    WriteMode::Rewrite
43  );
44
45  archive.add_file_from(
46    PathBuf::from( "external_footer.txt" ),
47    FileRef::new( PathBuf::from( "/templates/footer.hbs" ) ),
48    WriteMode::Rewrite
49  );
50
51  println!( "Archive with mixed content sources:" );
52  println!( "  Total files: {}", archive.file_count() );
53  println!();
54
55  // === Internalization Example ===
56
57  println!( "=== Internalization (fetch and embed) ===" );
58  println!();
59
60  // Create a mock filesystem with template content
61  let mut mock_fs = MemoryFileSystem::new();
62  mock_fs.write(
63    &PathBuf::from( "/templates/header.hbs" ),
64    "=== {{title}} ===\n"
65  )?;
66  mock_fs.write(
67    &PathBuf::from( "/templates/footer.hbs" ),
68    "© {{year}} {{author}}\n"
69  )?;
70
71  // Create resolver that can fetch from our mock filesystem
72  let _resolver = DefaultContentResolver::new();
73
74  // Note: DefaultContentResolver doesnt support actual file fetching,
75  // but demonstrates the API. In real usage, implement custom ContentResolver
76  // that reads from disk, HTTP, database, etc.
77
78  println!( "To internalize external content:" );
79  println!( "  let resolver = CustomContentResolver::new();" );
80  println!( "  archive.internalize( &resolver )?;" );
81  println!();
82  println!( "This fetches all external content and embeds it in the archive." );
83  println!();
84
85  // === Externalization Example ===
86
87  println!( "=== Externalization (extract to files) ===" );
88  println!();
89
90  // Create archive with inline content
91  let mut inline_archive = TemplateArchive::new( "app" );
92  inline_archive.add_text_file(
93    PathBuf::from( "config.txt" ),
94    "app={{app_name}}\nversion={{version}}\n",
95    WriteMode::Rewrite
96  );
97  inline_archive.add_text_file(
98    PathBuf::from( "readme.txt" ),
99    "# {{app_name}}\n",
100    WriteMode::Rewrite
101  );
102
103  println!( "Archive before externalization:" );
104  println!( "  Total files: {}", inline_archive.file_count() );
105  println!();
106
107  // Externalize would extract inline content to separate files
108  println!( "To externalize inline content:" );
109  println!( "  let storage = CustomContentStorage::new();" );
110  println!( "  archive.externalize( &storage, Path::new( \"/templates\" ) )?;" );
111  println!();
112  println!( "This extracts inline content to external files and updates references." );
113  println!();
114
115  // === Serialization with External Sources ===
116
117  println!( "=== Serialization ===" );
118  println!();
119
120  let json = archive.to_json_pretty()?;
121  println!( "JSON with external sources (first 600 chars):" );
122  let json_preview: String = json.chars().take( 600 ).collect();
123  println!( "{json_preview}" );
124  println!( "..." );
125  println!();
126
127  println!( "External file references are preserved in serialization." );
128  println!( "FileRef stores the path, not the content." );
129  println!();
130
131  // === Materialization ===
132
133  println!( "=== Materialization ===" );
134  println!();
135
136  // For demonstration, use inline content version
137  let mut demo_archive = TemplateArchive::new( "demo" );
138  demo_archive.add_text_file(
139    PathBuf::from( "output.txt" ),
140    "Title: {{title}}\nAuthor: {{author}}\nYear: {{year}}\n",
141    WriteMode::Rewrite
142  );
143
144  demo_archive.set_value( "title", Value::String( "External Content Guide".into() ) );
145  demo_archive.set_value( "author", Value::String( "genfile_core".into() ) );
146  demo_archive.set_value( "year", Value::Number( 2024 ) );
147
148  let renderer = HandlebarsRenderer::new();
149  let mut fs = MemoryFileSystem::new();
150
151  demo_archive.materialize_with_components(
152    PathBuf::from( "/output" ).as_path(),
153    &renderer,
154    &mut fs
155  )?;
156
157  let content = fs.read( &PathBuf::from( "/output/output.txt" ) )?;
158  println!( "Generated content:" );
159  println!( "{content}" );
160  println!();
161
162  println!( "✅ Example completed successfully" );
163
164  Ok( () )
165}
external_content/external_content.rs

external_content/
external_content.rs
