9biff

IMAP-to-9P notification bridge. Monitor an IMAP mailbox and write new message notifications to 9P file endpoints.

Quick Start

go build ./cmd/9biff
cp config.example.yaml config.yaml
# Edit config.yaml with your IMAP credentials and 9P endpoints
./9biff -config config.yaml

Configuration

9biff supports YAML, JSON, and TOML configuration files. Format is auto-detected from the file extension.

Field	Type	Required	Default	Description
imap.host	string	yes	—	IMAP server hostname
imap.port	int	yes	993	IMAP server port
imap.tls	string	yes	tls	TLS mode: tls, starttls, none
imap.username	string	yes	—	IMAP login username
imap.password	string	yes	—	IMAP login password
mailbox	string	no	INBOX	Mailbox to monitor
interval	duration	no	60s	Poll interval
template	string	no	{{.FromName}} <{{.From}}> - {{.Subject}}	Global default template
endpoints	array	yes	—	List of 9P endpoints
batch.enabled	bool	no	false	Enable message batching
batch.size	int	no	10	Max messages per batch
batch.timeout	duration	no	5s	Max wait before flushing batch

Endpoint Fields

Field	Type	Required	Default	Description
url	string	yes	—	9P server URL (tcp://host:port or unix:///path)
template	string	no	—	Per-endpoint template override
file_path	string	no	/	File path within 9P filesystem
timeout	duration	no	30s	Connection timeout
overwrite	bool	no	false	Overwrite file instead of appending

Environment Variable Overrides

All config values can be overridden via environment variables:

Variable	Config Field
9BIFF_IMAP_HOST	imap.host
9BIFF_IMAP_PORT	imap.port
9BIFF_IMAP_TLS	imap.tls
9BIFF_IMAP_USERNAME	imap.username
9BIFF_IMAP_PASSWORD	imap.password
9BIFF_MAILBOX	mailbox
9BIFF_INTERVAL	interval
9BIFF_TEMPLATE	template

Template Syntax

Notifications are rendered using Go's text/template syntax. Available template fields:

Field	Type	Description
.From	string	Sender email address
.FromName	string	Sender display name
.Subject	string	Email subject
.Timestamp	time.Time	Message date/time
.MessageID	string	Unique message identifier
.Snippet	string	First 200 characters of body
.Body	string	Full plain text body

Template Functions

Function	Description	Example
truncate N	Truncate to N chars	{{truncate 50 .Subject}}
timefmt "layout"	Format timestamp	{{timefmt "15:04" .Timestamp}}
upper	Uppercase	{{upper .Subject}}
lower	Lowercase	{{lower .From}}

Template Examples

# Default
{{.FromName}} <{{.From}}> - {{.Subject}}

# With timestamp
[{{timefmt "2006-01-02 15:04:05" .Timestamp}}] {{.From}} - {{.Subject}}

# Full detail
From: {{.FromName}} <{{.From}}>
Subject: {{.Subject}}
Date: {{timefmt "2006-01-02 15:04:05" .Timestamp}}
{{truncate 100 .Snippet}}

# Just subject
{{.Subject}}

Command-Line Flags

Flag	Description
-config <path>	Path to configuration file (default: config.yaml)
-version	Display version and exit

License

MIT