Web tail

Web application to view lines from file on local system or on remote server built with Svelte.

Installation

Download executable for your platform from latest release.

Docker image is also available here.

Configuration

Configuaration is done with web-tail.config.toml file. Following keys are available:

• port - port that Web tail will run on. Default value is 4444
• allowedOrigins - list of allowed origins for WebSocket connections. Default value is ["*"]
• servers - reusable servers configuration
  • name - name of server to use in sources configs
  • host - host of remote server. Mandatory field for source types ssh:*
  • port - port of remote server. Mandatory field for source types ssh:*
  • username - username for ssh connection to remote server. Mandatory for source types ssh:*
  • password - password to authenticate on remote server. Either this or privateKeyPath is mandatory for source types ssh:*
  • privateKeyPath - path to file with private key to authenticate on remote server. Either this or password is mandatory for source types ssh:*
• sources - list of sources to tail lines from
  • name - name of source. Mandatory field
  • type - type of source. Possible values: local:file, local:docker, local:openclaw, ssh:file, ssh:docker, ssh:openclaw. Mandatory field
  • path - path to file. Mandatory field for source types *:file
  • serverName - name of a server from servers list
  • containerId - Docker container ID. Mandatory field for source types *:docker
  • host - host of remote server. Mandatory field for source types ssh:*
  • port - port of remote server. Mandatory field for source types ssh:*
  • username - username for ssh connection to remote server. Mandatory for source types ssh:*
  • password - password to authenticate on remote server. Either this or privateKeyPath is mandatory for source types ssh:*
  • privateKeyPath - path to file with private key to authenticate on remote server. Either this or password is mandatory for source types ssh:*

String fields support environment placeholders in the exact form ${VAR_NAME}. If a placeholder is used and the environment variable is not set, web-tail fails to start with a config error. Only exact placeholders are expanded, so values like prefix-${VAR_NAME} stay unchanged.

Example:

[[servers]]
name = "production"
host = "${SSH_HOST}"
port = 22
username = "${SSH_USER}"
password = "${SSH_PASSWORD}"
privateKeyPath = "${SSH_PRIVATE_KEY_PATH}"

[[sources]]
name = "app-log"
type = "ssh:file"
path = "/var/log/app.log"
serverName = "production"

Usage

Options from left to right:

• Dropdown to select one of sources from web-tail.config.toml
• Search field. Matching results will be selected. Search is case insensitive by default
• Filter toggle. If enabled only lines with matching results are shown
• .* toggle. If enabled treats text in search field as regular expression
• Aa toggle. If enabled makes search case sensitive
• Reverse toggle. If enabled latest lines shown on top
• Max lines field. How much lines will be shown

Development

Frontend app lives in /client and uses Bun + Vite.

1. Install frontend dependencies:
   • cd client && bun install
2. Build frontend assets for Go embed:
   • cd client && bun run build
3. Run backend:
   • go run ./server

For frontend HMR in development, run both services:

• go run ./server
• cd client && bun run dev

Vite dev server proxies /sources and /logstream to http://localhost:4444.