Files
mesh-controller/internal/catalogue/setting_into.go
T
mesh-tools 97a2d841c7 Land feature 57's controller work on its release branch
The controller plans config, templates and moved providers' provisions,
hands bus accounts to the vault and judges the new manifest words, on the
feature's SDK and node-engine validator (feature 57, config and provisioning).
2026-10-15 21:27:33 +00:00

368 lines
15 KiB
Go

package catalogue
import (
"errors"
"fmt"
"regexp"
"sort"
"strconv"
"strings"
)
// An operator's value, where a definition needs one (novox/hq ADR 0112, ADR 0155, design 27).
//
// A mail server's domain, a site's name, the address a proxy forwards from: values that are true of
// one installation and of no other, and that a module's software must be told. They had nowhere to
// live but the definition, which is how a catalogue meant for any mesh came to name this one
// (novox/hq issues 122, 134). ADR 0112 names the operator as one of the four providers; this is the
// operator answering.
//
// `${setting:<key>}` in a file's content, in a service's unit name and in a directory's owner (a uid or
// gid only, issue 279) is filled from the module's settings layers — the mesh's,
// then this node's — the same layers a mergeable JSON file and a contribution already take, so
// `settings set <module>` is the one place a person's values go. **Refused when no layer sets it**,
// naming the key and the remedy: a definition that carried a default for a mail domain would be
// carrying the very literal this removes, and a blank written silently would be a service that
// comes up wrong somewhere that names neither the module nor the key.
// settingRef is how a definition asks for an operator's value: ${setting:<key>}.
var settingRef = regexp.MustCompile(`\$\{setting:([a-z0-9][a-z0-9_.-]*)\}`)
// settingsUsed is every key a file's content asks for, once each, in order of first use.
func settingsUsed(content string) []string {
var keys []string
seen := map[string]bool{}
for _, m := range settingRef.FindAllStringSubmatch(content, -1) {
if !seen[m[1]] {
seen[m[1]] = true
keys = append(keys, m[1])
}
}
return keys
}
// UnsetSettingError is a module whose definition says ${setting:<key>} where nothing sets that key: typed, so
// that whoever reads why a module was left out of a machine can tell a setting nobody gave — the operator's
// to give, named with the command that gives it — from any other reason (novox/hq issue 380). Its words are
// the refusal's, unchanged.
type UnsetSettingError struct {
Module, Setting string
said string
// where says what asks for it — "a file", "a service whose unit", "a directory <id> whose owner" — and
// setToday which of the module's keys a layer sets, for saying it again in the config form's words.
where, setToday string
}
func (e *UnsetSettingError) Error() string { return e.said }
// unsetInConfigWords is the refusal of a required config value nothing sets, in the words of a module written in the
// config form (novox/hq ADR 0348 §1, §4): `${config:<key>}` and the config verb, never `settings set`. Any other
// error, and any error of a module in the settings form, is returned as it was.
func unsetInConfigWords(err error, m Manifest) error {
var unset *UnsetSettingError
if err == nil || !m.DeclaresConfig() || !errors.As(err, &unset) {
return err
}
return &UnsetSettingError{Module: unset.Module, Setting: unset.Setting, where: unset.where,
setToday: unset.setToday, said: fmt.Sprintf(
"%s has %s that says ${config:%s}, and nothing sets the required config value %q for it — a "+
"required value is the operator's own and has no default (novox/hq ADR 0348 §4): set it with "+
"the config verb, for %s on this node, key %q%s",
unset.Module, unset.where, unset.Setting, unset.Setting, unset.Module, unset.Setting,
strings.ReplaceAll(unset.setToday, "no setting is set", "no config value is set"))}
}
// settingInto fills a file's ${setting:…} placeholders from the layers over a module.
//
// The last layer setting a key wins, which is the node's over the mesh's over the module's own
// default (novox/hq ADR 0262) — the same order settle applies to a mergeable file. The caller lays
// the defaults under the layers with WithDefaults. A value that is not a string is written the way a program would read
// it (a number without a trailing .000000, a boolean as true/false).
func settingInto(resource map[string]any, layers []Layer, module string) error {
if fmt.Sprint(resource["type"]) == "service" {
return settingIntoUnit(resource, layers, module)
}
if fmt.Sprint(resource["type"]) == "directory" {
return settingIntoOwner(resource, layers, module)
}
if fmt.Sprint(resource["type"]) != "file" {
return nil
}
content, ok := resource["content"].(string)
if !ok {
return nil
}
for _, key := range settingsUsed(content) {
value, set := settingValue(layers, key)
if !set {
return &UnsetSettingError{Module: module, Setting: key, where: "a file",
setToday: orNoSettings(layers), said: fmt.Sprintf(
"%s has a file that says ${setting:%s}, and nothing sets %q for it — an operator's "+
"value is the assignment's, never the definition's (novox/hq ADR 0112), and only a "+
"preference has a default in the definition (ADR 0262): "+
"`settings set %s <file>` with {%q: …}%s",
module, key, key, module, key, orNoSettings(layers))}
}
content = strings.ReplaceAll(content, "${setting:"+key+"}", plainly(value))
}
resource["content"] = content
return nil
}
// unitPart is what a setting may put into a unit's name: the characters systemd allows in a unit name,
// less the instance's `@` and the escape's `\`, and at least one of them. Anything else — a space, a slash,
// a newline that would begin a directive in the unit file the name ends up in — is refused, never written.
var unitPart = regexp.MustCompile(`^[A-Za-z0-9:_.][A-Za-z0-9:_.-]{0,63}$`)
// unitInstance is the one place a setting may stand in a unit's name: the whole instance of a template,
// after its `@` and before its suffix — `zfs-scrub-weekly@${setting:scrub-pool}.timer` — so a value can
// make the unit another instance of the same template and nothing else (third review of mesh-catalog #147).
var unitInstance = regexp.MustCompile(`^[A-Za-z0-9:_.-]+@\$\{setting:[a-z0-9][a-z0-9_.-]*\}\.[a-z]+$`)
// UnitSettingProblems refuses, where a manifest is read, a service whose unit name carries a setting
// anywhere but as a template's whole instance.
func UnitSettingProblems(m Manifest) []string {
var problems []string
for _, r := range m.Resources {
if fmt.Sprint(r["type"]) != "service" {
continue
}
unit, _ := r["unit"].(string)
if len(settingsUsed(unit)) == 0 && !strings.Contains(unit, "${setting:") {
continue
}
if !unitInstance.MatchString(unit) {
problems = append(problems, fmt.Sprintf("%s: the service %v's unit %q carries a setting outside a template's "+
"instance; a setting may stand only as the whole instance, after the @ and before the suffix "+
"(name@${setting:key}.timer)", m.Module, r["id"], unit))
}
}
return problems
}
// settingIntoUnit fills ${setting:…} in a service resource's unit name: a module that holds the
// distribution's timer for the pool the operator names cannot write the pool into its definition
// (novox/hq ADR 0112). Refused, with the key and why, when nothing sets it or the value would not make a
// unit's name; the resource is left as it was.
func settingIntoUnit(resource map[string]any, layers []Layer, module string) error {
unit, ok := resource["unit"].(string)
if !ok {
return nil
}
for _, key := range settingsUsed(unit) {
value, set := settingValue(layers, key)
if !set {
return &UnsetSettingError{Module: module, Setting: key, where: "a service whose unit",
setToday: orNoSettings(layers), said: fmt.Sprintf(
"%s has a service whose unit says ${setting:%s}, and nothing sets %q for it — an operator's "+
"value is the assignment's, never the definition's (novox/hq ADR 0112): "+
"`settings set %s <file>` with {%q: …}%s",
module, key, key, module, key, orNoSettings(layers))}
}
v := plainly(value)
if !unitPart.MatchString(v) {
return fmt.Errorf("%s: the setting %q is %q, which cannot be the instance of the unit %s: an instance "+
"takes letters, digits, ':', '_', '.' and '-', does not begin with '-' (a systemctl option), and is "+
"at most 64 characters", module, key, v, unit)
}
unit = strings.ReplaceAll(unit, "${setting:"+key+"}", v)
}
resource["unit"] = unit
return nil
}
// A declared directory may be owned by the account its module runs as (novox/hq issue 279).
//
// A containerised module runs as the identity its assignment sets per node — its puid and pgid
// settings, written into the environment file its image reads (ADR 0112, issue 153) — and a directory
// its app must write, beyond the one its image re-owns at start, was owned by whatever the manifest
// spelt: right on a machine whose identity matched the image's default, refused by the app on one whose
// did not. So a directory's `owner` may name the settings that identity is: `${setting:<key>}` for the
// user alone, `${setting:<user>}:${setting:<group>}` for both, filled from the same layers at
// composition.
//
// **Whole numbers only.** An owner a setting fills is a uid or a gid — never an account's name, never
// text — so no value can put anything into the ownership the node-engine applies but a number; one that
// is not is refused at composition, naming the key, and the directory is left as it was. The shape is
// judged where the manifest is read (OwnerSettingProblems): each side of the colon a whole placeholder
// or a whole number, and every key one the module itself asks for elsewhere — in a file, a unit, a
// contribution or a served fact — or declares a default for, so the owner follows the identity its
// process is told it runs as, never a key that reaches nothing else.
// ownerSide is one side of an owner a setting may fill: a whole placeholder or a whole number.
var ownerSide = `(?:\$\{setting:[a-z0-9][a-z0-9_.-]*\}|[0-9]+)`
// ownerWithSetting is the only shape an owner holding a setting may have: user, or user:group.
var ownerWithSetting = regexp.MustCompile(`^` + ownerSide + `(?::` + ownerSide + `)?$`)
// wholeID is a value as a uid or a gid, and whether it is one: a whole number below the kernel's "no id"
// (2^32-1). Uid 0 is one: a key an owner asks for is the controller's terminal's alone (TerminalKeys).
func wholeID(v string) (uint64, bool) {
if v == "" || strings.TrimLeft(v, "0123456789") != "" {
return 0, false
}
n, err := strconv.ParseUint(v, 10, 32)
return n, err == nil && n < 1<<32-1
}
// OwnerSettingProblems refuses, where a manifest is read, a directory whose owner carries a setting
// in any shape but a whole placeholder or number on each side of the colon, or names a key the module
// asks for nowhere else and declares no default for.
func OwnerSettingProblems(m Manifest) []string {
var problems []string
asked := settingKeysAskedOutsideOwners(m)
for k := range m.Settings {
asked[k] = true
}
for _, r := range m.Resources {
owner, _ := r["owner"].(string)
if !strings.Contains(owner, "${setting:") {
continue
}
if fmt.Sprint(r["type"]) != "directory" {
// Said by the placeholder sweep: only a directory's owner takes a setting.
continue
}
if !ownerWithSetting.MatchString(owner) {
problems = append(problems, fmt.Sprintf("%s: the directory %v's owner %q carries a setting in a shape "+
"the mesh does not fill; an owner names the account by number only, each side of the colon a whole "+
"${setting:key} or a whole number (${setting:puid}:${setting:pgid}) (novox/hq issue 279)",
m.Module, r["id"], owner))
continue
}
// A template's text is not here yet, so what the module asks for elsewhere cannot be known: WithTemplatesFrom
// parses its result again with every template filled, and this half is judged then (as config.go skips its
// "placed nowhere" rule while m.Templated()).
if m.Templated() {
continue
}
for _, key := range settingsUsed(owner) {
if !asked[key] {
problems = append(problems, fmt.Sprintf("%s: the directory %v's owner says ${setting:%s}, and the "+
"module asks for %q nowhere else and declares no default for it: an owner follows the identity "+
"the module's process is told it runs as (its identity file's ${setting:%s}), never a key of its "+
"own (novox/hq issue 279)", m.Module, r["id"], key, key, key))
}
}
}
return problems
}
// settingIntoOwner fills ${setting:…} in a directory's owner, refusing — with the key and why, the
// resource left as it was — a key nothing sets and a value that is not a whole number.
func settingIntoOwner(resource map[string]any, layers []Layer, module string) error {
owner, ok := resource["owner"].(string)
if !ok {
return nil
}
for _, key := range settingsUsed(owner) {
value, set := settingValue(layers, key)
if !set {
return &UnsetSettingError{Module: module, Setting: key,
where: fmt.Sprintf("a directory %v whose owner", resource["id"]), setToday: orNoSettings(layers),
said: fmt.Sprintf(
"%s has a directory %v whose owner says ${setting:%s}, and nothing sets %q for it — an operator's "+
"value is the assignment's, never the definition's (novox/hq ADR 0112): "+
"`settings set %s <file>` with {%q: …}%s",
module, resource["id"], key, key, module, key, orNoSettings(layers))}
}
v := plainly(value)
id, whole := wholeID(v)
if !whole {
return fmt.Errorf("%s: the setting %q is %q, which cannot own the directory %v: an owner a setting "+
"names is a uid or a gid, a whole number, never an account's name or other text (novox/hq issue 279)",
module, key, v, resource["id"])
}
// Written as the number parsed, so "0001" reaches the node-engine as 1, never as text.
owner = strings.ReplaceAll(owner, "${setting:"+key+"}", strconv.FormatUint(id, 10))
}
resource["owner"] = owner
return nil
}
func settingValue(layers []Layer, key string) (any, bool) {
var value any
set := false
for _, layer := range layers {
if v, has := layer.Values[key]; has {
value, set = v, true
}
}
return value, set
}
func orNoSettings(layers []Layer) string {
var keys []string
for _, l := range layers {
if l.Default {
continue
}
for k := range l.Values {
keys = append(keys, k)
}
}
if len(keys) == 0 {
return "; no setting is set for this module"
}
sort.Strings(keys)
return "; set today: " + strings.Join(keys, ", ")
}
// settingKeysUsedBy is every key a module's files, units, directory owners, contributions and served
// facts ask for, so a setting that lands in one is not called stray.
func settingKeysUsedBy(m Manifest) map[string]bool {
used := settingKeysAskedOutsideOwners(m)
for _, r := range m.Resources {
if fmt.Sprint(r["type"]) == "directory" {
if owner, ok := r["owner"].(string); ok {
for _, k := range settingsUsed(owner) {
used[k] = true
}
}
}
}
return used
}
// settingKeysAskedOutsideOwners is every key a module's files, units, contributions and served facts
// ask for: what a directory's owner may follow (OwnerSettingProblems).
func settingKeysAskedOutsideOwners(m Manifest) map[string]bool {
used := map[string]bool{}
note := func(s string) {
for _, k := range settingsUsed(s) {
used[k] = true
}
}
for _, r := range m.Resources {
switch fmt.Sprint(r["type"]) {
case "file":
if content, ok := r["content"].(string); ok {
note(content)
}
case "service":
if unit, ok := r["unit"].(string); ok {
note(unit)
}
}
}
inValues := func(values map[string]any) {
for _, v := range values {
if s, ok := v.(string); ok {
note(s)
}
}
}
for _, values := range m.Contributes {
inValues(values)
}
for _, locals := range m.ContributesMany {
for _, values := range locals {
inValues(values)
}
}
for _, values := range m.Serves {
inValues(values)
}
return used
}