Basic configuration

This patch introduces a basic on disk configuration, comprised of a main
configuration file and per-domain directories.

It's still not complete, but will be extended in subsequent patches.

internal/config/config.pb.go

@@ -0,0 +1,43 @@
+// Code generated by protoc-gen-go.
+// source: config.proto
+// DO NOT EDIT!
+
+/*
+Package config is a generated protocol buffer package.
+
+It is generated from these files:
+	config.proto
+
+It has these top-level messages:
+	Config
+*/
+package config
+
+import proto "github.com/golang/protobuf/proto"
+import fmt "fmt"
+import math "math"
+
+// Reference imports to suppress errors if they are not otherwise used.
+var _ = proto.Marshal
+var _ = fmt.Errorf
+var _ = math.Inf
+
+type Config struct {
+	// Hostname to use when we say hello.
+	// For aesthetic purposes, but may help if our ip address resolves to it.
+	// Default: machine hostname.
+	Hostname string `protobuf:"bytes,1,opt,name=hostname" json:"hostname,omitempty"`
+	// Maximum email size, in megabytes.
+	// Default: 50.
+	MaxDataSizeMb int64 `protobuf:"varint,2,opt,name=max_data_size_mb" json:"max_data_size_mb,omitempty"`
+	// Addresses to listen on.
+	// Default: "systemd", which means systemd passes sockets to us.
+	Address []string `protobuf:"bytes,3,rep,name=address" json:"address,omitempty"`
+	// Address for the monitoring http server.
+	// Default: no monitoring http server.
+	MonitoringAddress string `protobuf:"bytes,4,opt,name=monitoring_address" json:"monitoring_address,omitempty"`
+}
+
+func (m *Config) Reset()         { *m = Config{} }
+func (m *Config) String() string { return proto.CompactTextString(m) }
+func (*Config) ProtoMessage()    {}