blueline

A lightweight, profile-based HTTP client with REPL interface.

Overview

Blueline is a modern command-line HTTP client featuring:

• REPL Interface: Interactive Read-Eval-Print Loop with vi-style navigation
• Profile-based Configuration: Store and reuse connection settings, headers, and authentication
• Security-first Design: REPL-only mode prevents piped input vulnerabilities
• Split-pane UI: Request editing and response viewing in separate panes
• JSON Support: Automatic JSON formatting and syntax highlighting
• Verbose Mode: Detailed connection and request/response information

Installation

From Source

git clone https://github.com/samwisely75/blueline
cd blueline
cargo build --release

From Package Managers

Note: Package manager releases coming soon

Quick Start

Basic Usage

# Start blueline with default profile
blueline

# Start with specific profile
blueline -p staging

# Start with verbose output
blueline -v

Profile Configuration

Create ~/.blueline/profile with your API configurations:

[default]
host = https://api.example.com
@content-type = application/json
@accept = application/json

[staging]
host = https://staging-api.example.com
@authorization = Bearer your-token-here
user = username
password = secret

[local]
host = http://localhost:8080
@content-type = application/json
insecure = true

REPL Commands

Once in the REPL interface:

• Navigation: Use vi-style keys (h, j, k, l) to move around
• Insert Mode: Press i to enter insert mode for editing
• Normal Mode: Press Esc to return to normal mode
• Execute Request: Press Enter to send the HTTP request
• Quit: Press :q or Ctrl+C to exit

Command Line Options

blueline [OPTIONS]

Options:
  -p, --profile <PROFILE>    Use specified profile from ~/.blueline/profile [default: default]
  -v, --verbose              Enable verbose output showing connection details
  -h, --help                 Print help information
  -V, --version              Print version information

Profile Configuration Reference

Connection Settings

• host - Base URL for API endpoints (required)
• insecure - Skip TLS certificate verification (true/false)
• ca_cert - Path to custom CA certificate file
• proxy - HTTP/HTTPS proxy URL

Authentication

• user - Username for Basic Authentication
• password - Password for Basic Authentication

Headers

Prefix header names with @:

• @authorization - Authorization header
• @content-type - Content-Type header
• @accept - Accept header
• @user-agent - User-Agent header

Example Profile

[production]
host = https://api.production.com
@authorization = Bearer prod-token-here
@content-type = application/json
@accept = application/json
user = api-user
password = secure-password
ca_cert = /etc/ssl/certs/production-ca.pem
proxy = http://corporate-proxy:8080
insecure = false

REPL Interface

Split-Pane Layout

┌─────────────────────────────────┐
│          Request Pane           │
│                                 │
│ Method: GET                     │
│ Path: /api/users                │
│ Body: {"name": "John"}          │
│                                 │
├─────────────────────────────────┤
│         Response Pane           │
│                                 │
│ Status: 200 OK                  │
│ {                               │
│   "users": [...]                │
│ }                               │
└─────────────────────────────────┘

Vi-Style Navigation

• h - Move cursor left
• j - Move cursor down
• k - Move cursor up
• l - Move cursor right
• w - Move to next word
• b - Move to previous word
• 0 - Move to beginning of line
• $ - Move to end of line

Editing Commands

• i - Enter insert mode at cursor
• a - Enter insert mode after cursor
• o - Insert new line below and enter insert mode
• x - Delete character under cursor
• dd - Delete current line
• u - Undo last change

Verbose Mode

When using -v flag, blueline displays detailed information:

Connection Details

> connection:
>   host: https://api.example.com
>   port: 443
>   scheme: https
>   ca-cert: <none>
>   insecure: false
>   headers:
>    content-type: application/json
>    authorization: Bearer token
>   proxy: <none>

Request Information

> request:
>   method: POST
>   path: /api/users
>   body: {"name": "John", "email": "john@example.com"}

Response Details

> response:
>   status: 201 Created
>   headers:
>     content-type: application/json
>     location: /api/users/123

Security Features

• No piped input: Prevents injection attacks through stdin
• Profile isolation: Credentials stored separately from commands
• TLS verification: Certificate validation enabled by default
• Secure defaults: Conservative configuration options

Architecture

Blueline uses the bluenote HTTP client library for profile-based HTTP requests. The bluenote library provides reusable HTTP client functionality with configuration management that can be used independently in other Rust projects.

Development

Building

# Build entire workspace
cargo build

# Build specific crate (now just blueline)
cargo build --package blueline

# Run tests
cargo test

Project Structure

blueline/
├── blueline/           # REPL application crate
│   ├── src/
│   │   ├── main.rs     # Application entry point
│   │   ├── cmd.rs      # Command line parsing
│   │   └── repl.rs     # REPL interface
│   └── tests/          # Integration tests
└── Cargo.toml          # Workspace configuration

License

Licensed under the Elastic License 2.0. See LICENSE file for details.

Contributing

Contributions are welcome! Please:

1. Fork the repository
2. Create a feature branch
3. Make your changes
4. Add tests for new functionality
5. Ensure all tests pass
6. Submit a pull request

Related Projects

• httpc: Command-line HTTP client (predecessor)
• curl: Classic HTTP client tool
• httpie: Modern HTTP client
• postman: GUI API testing tool