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hello_cli ​

A comprehensive CLI application demonstrating various commands and third-party integrations.

Source Code ​

Path: examples/hello_cli/

Features Demonstrated ​

  • CLI command framework (tk.cli)
  • HTTP client integration
  • HTML to Markdown conversion
  • DOM parsing and querying
  • PDF generation
  • Regular expressions and grep functionality
  • GitHub API integration
  • Hacker News API integration

Available Commands ​

hello ​

Print a greeting message.

sh
zig build run -- hello

hn <limit> ​

Show top Hacker News stories.

sh
zig build run -- hn 5

gh <owner> ​

List GitHub repositories for a user.

sh
zig build run -- gh cztomsik

scrape <url> [selector] ​

Scrape a URL and convert to Markdown, with optional CSS selector.

sh
zig build run -- scrape https://example.com
zig build run -- scrape https://example.com "article.content"

grep <file> <pattern> ​

Search for a regex pattern in a file.

sh
zig build run -- grep myfile.txt "TODO.*"

substr <str> [start] [end] ​

Get substring with bounds checking.

sh
zig build run -- substr "Hello World" 0 5

pdf <filename> <title> ​

Generate a sample PDF with various shapes and text.

sh
zig build run -- pdf output.pdf "My Document"

Architecture ​

The CLI uses a shared App struct for services (HTTP client, API clients) and a Cli struct for command definitions:

zig
const App = struct {
    http_client: tk.http.StdClient,
    hn_client: tk.hackernews.Client,
};

const Cli = struct {
    cmds: []const tk.cli.Command = &.{
        .usage,
        .cmd0("hello", "Print a greeting message", hello),
        .cmd1("hn", "Show top Hacker News stories", hn_top),
        // ...
    },
};

Command Handler Patterns ​

Handlers can inject dependencies:

  • arena: std.mem.Allocator - Per-command arena allocator
  • Service dependencies (e.g., *tk.http.Client)
  • Command arguments as function parameters

Running ​

sh
cd examples/hello_cli
zig build run -- <command> [args...]

Next Steps ​