jschoubben
71f77617e3
A contribution that is not a credential grant — a module offering something to another on its own machine — has nobody to be identified to, and was carrying an empty `as`. A field that is always present and usually empty teaches a reader to ignore it, including when it is not.
641 lines
28 KiB
Go
641 lines
28 KiB
Go
package catalogue
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// Turning a resolution into the declaration a node is sent.
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//
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// Separate from resolving because they answer different questions. Resolving asks *what should
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// this machine run*; this asks *what does that look like as resources*, and the second is where
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// settings are applied, generators are called, contributions are collected and credentials are
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// placed. Both lived in one file until it was doing four jobs at once — which is the shape the
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// system this replaces failed in, one import at a time.
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import (
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"encoding/json"
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"fmt"
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"sort"
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"strings"
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)
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// SettingsBy is the layers that apply to each module, keyed by module name.
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type SettingsBy map[string][]Layer
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// Generator works out a module's resources for one node, where they cannot be written in advance.
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type Generator interface {
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// Resources for this node. Absent means the node is not part of whatever this generates,
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// which is an ordinary answer rather than a failure — a machine assigned the module before it
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// has an address on the network is in exactly that state.
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Resources(node string) ([]map[string]any, bool, error)
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}
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// OpensPorts is a generator that also says what its resources accept connections on.
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//
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// **Separate from Generator, because most generators have nothing to say here** and requiring an
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// empty method of each would be a cost paid everywhere for one caller.
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//
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// It exists because a static field cannot express this. A hub accepts connections from every node
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// at other sites; a machine that is not a hub dials out and needs nothing open — and they are the
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// same module. `listens` in a manifest is one answer for every machine that runs it, so the
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// machine that most needs filtering, the one facing the public internet, was the one whose rule
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// set would have closed its own overlay.
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type OpensPorts interface {
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// Listens is what this node accepts on because of what was computed for it. Nothing is the
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// ordinary answer: most machines running a computed module open no port at all.
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Listens(node string) ([]Listening, error)
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}
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// Grant is one consumer's credential, on the machine that must create it.
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type Grant struct {
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// Provision is what was required.
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Provision string
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// Consumer is the node that will use it.
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Consumer string
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// From is the module on that machine which asked.
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//
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// **Part of who this credential is for, not a label** (novox/hq 04-ISSUES/022). Together with
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// Consumer it names one consumer; the node alone does not, because a machine routinely runs
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// several modules wanting the same thing. It is also what the provider names the role or the
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// bucket or the client after, so withdrawing one consumer does not take another's away.
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From string
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// Values are what that module contributed — the name it wants, and anything else the
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// provision's own vocabulary defines.
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Values map[string]any
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// At is where the consuming machine is on the private network, empty if it is not on one.
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//
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// Passed in with the grant because it is a fact about another machine, and resolution answers
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// questions about one. A provider that must reach back to its consumer — a reverse proxy is
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// the whole reason this exists — otherwise has to know how the mesh names machines.
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At string
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// Sealed is the credential, closed to the providing node.
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Sealed string
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}
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// Rendering is everything needed to turn a resolution into the declaration a node is sent.
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type Rendering struct {
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// Certificate is what the mesh issued for this machine's internal name, and the mesh's own
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// certificate. Both public — the key they belong to never left the machine.
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Certificate string
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Authority string
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// Needed is each module's own secrets, sealed to this node, keyed by module and then by the
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// name the module gave it.
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Needed map[string]map[string]string
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// Mesh is every node's address on the private network, which is what a rule saying "from the
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// mesh" resolves to. Passed in for the same reason grants are: who else is on the network is
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// a fact about the mesh, and resolution answers questions about one machine.
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Mesh []string
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// Names is every machine's internal name and its address, for containers to be given.
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//
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// **A container does not inherit the machine's names**, so every internal name the mesh wrote
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// is invisible to what the machine runs. Given here rather than looked up on the machine,
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// because which machines exist is a fact about the mesh.
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Names map[string]string
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Settings SettingsBy
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Generators map[string]Generator
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// Grants are the credentials this node must create, for the provisions it offers. Passed in
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// rather than resolved, because who consumes a node is a fact about the rest of the mesh and
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// resolution answers questions about one machine.
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Grants []Grant
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}
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// Declaration is everything the resolved modules put on the node, with settings applied.
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//
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// Resource identities are prefixed with the module they came from. Two modules may reasonably
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// both call something "config", and without this the second would silently replace the first —
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// the node applying one of them and reporting success.
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func (r Resolution) Declaration(with Rendering) ([]map[string]any, error) {
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// Where each provision's credentials land, so a contribution can name the file rather than
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// carry a value the mesh does not have.
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directories := map[string]string{}
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for _, m := range r.Modules {
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for provision, where := range m.Grants {
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directories[provision] = where
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}
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}
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given, err := r.contributions(with.Settings, with.Grants, directories)
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if err != nil {
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return nil, err
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}
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// Once, from every module's listens -- not per module. A module receiving only its own ports
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// would write a rule set that closed every other module on the machine.
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rules, err := r.Filtering(with.Generators)
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if err != nil {
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return nil, err
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}
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filtering := AsNftables(rules, with.Mesh)
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var out []map[string]any
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for _, m := range r.Modules {
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resources := m.Resources
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// What the mesh computes for this module goes FIRST, before the module's own resources.
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//
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// **Order is stated, not derived — the host does not sort** (novox/hq ADR 0005), so
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// whatever the mesh writes down is the order a machine applies. A module's service or
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// container routinely depends on one of these files; nothing here ever depends on a
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// module's resources, because none of it is computed from them.
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//
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// Appended, this was wrong in a way that only showed on the first apply and then healed:
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// the service started before its certificate or its rule set existed, failed, and the next
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// reconcile fixed it. A fault that repairs itself on the second attempt is worse than one
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// that does not, because what gets remembered is that it works.
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var first []map[string]any
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if f := m.Filtering; f != nil {
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first = append(first, map[string]any{
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"id": FilteringID(), "type": "file", "path": f.Into,
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"content": filtering, "mode": "0600",
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})
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}
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if c := m.Certificate; c != nil {
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if with.Certificate == "" {
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// Asked for and not issued. Refused rather than skipped: a module that serves TLS
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// with no certificate does not start, and the reason is somewhere else entirely.
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return nil, fmt.Errorf(
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"%s wants a certificate for this machine and none was issued", m.Module)
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}
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first = append(first, map[string]any{
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"id": CertificateID(), "type": "file", "path": c.Into,
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// Public. It travels in the open like any other file, because it is a statement
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// about a key rather than the key.
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"content": with.Certificate, "mode": "0644",
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})
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if c.Authority != "" {
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first = append(first, map[string]any{
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"id": AuthorityID(), "type": "file", "path": c.Authority,
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"content": with.Authority, "mode": "0644",
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})
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}
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}
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for _, name := range sortedKeys(m.OwnSecrets) {
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sealed := with.Needed[m.Module][name]
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if sealed == "" {
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// Declared and not made. Refused rather than skipped: a module whose own
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// credential is silently absent starts, fails to authenticate, and the reason is
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// three layers away from the machine reporting it.
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return nil, fmt.Errorf(
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"%s needs a secret called %q and none was made for it", m.Module, name)
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}
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first = append(first, map[string]any{
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"id": NeedID(name), "type": "file", "path": m.OwnSecrets[name], "sealed": sealed,
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})
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}
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for _, to := range sortedKeys(m.Secrets) {
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var found *Needed
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for i, n := range r.Needs {
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// **This module's need, not the provision's** (novox/hq 04-ISSUES/022). Matching
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// on the name alone, every consumer of a provision took whichever credential
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// happened to be last in the list — so on a node with two of them, one module
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// would be given the other's password and fail to authenticate with a valid
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// credential belonging to somebody else.
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if n.Name == to && n.For == m.Module {
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found = &r.Needs[i]
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}
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}
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if found != nil && found.ByRecord && found.Sealed == "" {
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// Answered by a record whose key has not been supplied since this consumer was
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// put on it. **Refused, not skipped.** The mesh discarded the plaintext when the
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// key was accepted and cannot seal another, so a machine that resolved cleanly
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// would receive no file at all and fail at whatever tried to read it — which is
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// the outcome ADR 0024 exists to avoid, arrived at politely.
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return nil, fmt.Errorf(
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"%s on this machine uses the licence %q and no key has been sealed to it. "+
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"The mesh cannot make one; supply it again with `licence key %s`",
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m.Module, found.From, found.From)
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}
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if found == nil || found.Sealed == "" {
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// Answered on this machine, or answered by a node the mesh could not seal to.
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// Nothing to write either way, and writing an empty credential file would be
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// worse than none: something would read it and fail authenticating.
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continue
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}
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first = append(first, map[string]any{
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"id": SecretID(to), "type": "file", "path": m.Secrets[to],
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"sealed": found.Sealed,
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})
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}
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for _, to := range sortedKeys(m.Grants) {
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for _, g := range with.Grants {
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if g.Provision != to {
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continue
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}
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if g.From == "" {
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// Nothing on that machine asks for this any more. Skipped here rather than
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// where grants are gathered, so the rule holds whoever gathers them.
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//
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// **This is how a credential is withdrawn.** The provisioner removes what
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// nobody asks for, and it can only do that if the mesh stops asking — a
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// consumer that was unassigned would otherwise keep a working login for ever,
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// and nothing would say so.
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continue
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}
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first = append(first, map[string]any{
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"id": GrantID(to, g.Consumer+"."+g.From),
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"type": "file",
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"path": grantPath(m.Grants[to], g.Consumer, g.From),
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"sealed": g.Sealed,
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})
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}
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}
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for _, to := range sortedKeys(m.Binds) {
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var found *Needed
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for i, n := range r.Needs {
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if n.Name == to && n.For == m.Module {
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found = &r.Needs[i]
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}
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}
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if found == nil {
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// Answered on this same machine rather than from elsewhere in the mesh.
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//
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// **Still written.** It used to be skipped, reasoning that "it is on this node"
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// is a fact nobody needs — and that is true of the *location* and false of
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// everything beside it. A binding also carries what the provider said a consumer
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// must know, which is the port; a consumer cannot invent that, and got an absent
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// file with no explanation. A build machine sharing a node with the registry it
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// pushes to sat in a loop saying it could not read its own binding.
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here := here(r, to)
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if here == nil {
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// Nothing in this node's set offers it either, so there is genuinely nothing
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// to say. Resolution has already refused anything unanswerable, so this is a
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// requirement met by the module itself.
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continue
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}
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found = here
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}
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file, err := boundFile(*found, m.Binds[to], ConsumerIdentity(r.Node, m.Module))
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if err != nil {
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return nil, err
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}
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first = append(first, file)
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}
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for _, to := range sortedKeys(m.Receives) {
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file, err := receivedFile(to, m.Receives[to], given[to])
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if err != nil {
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return nil, err
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}
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first = append(first, file)
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}
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if m.Computed != "" {
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generator, known := with.Generators[m.Computed]
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if !known {
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return nil, fmt.Errorf(
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"%s says its resources are computed by %q, and this control plane has no %q",
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m.Module, m.Computed, m.Computed)
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}
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generated, part, err := generator.Resources(r.Node)
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if err != nil {
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return nil, err
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}
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if !part {
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// Assigned, and not yet part of what this generates. Nothing to put on the
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// machine, which is different from an error: a node given the network module
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// before it has an address is in exactly that state, briefly.
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continue
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}
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resources = generated
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}
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// Now, and not before: a module whose resources are computed replaces them wholesale, and
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// merging earlier would throw away the files it still needs.
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resources = append(append([]map[string]any{}, first...), resources...)
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// Every container is given the mesh's names. Not a choice a module makes: a module that
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// listed them would go stale the day a machine joins, and one that did not would be a
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// module whose containers cannot reach anything by name.
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//
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// A container that was given names of its own keeps them and gets the mesh's beside them:
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// the mesh does not know what else a workload needs to reach, and taking something away
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// to add something is not what "also" means.
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if len(with.Names) > 0 {
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resources = withMeshNames(resources, with.Names)
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}
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// What this module may name from inside one of its own files. Gathered once per module
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// rather than per file, because it is a fact about the module.
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sealed, err := sealedFor(m, r.Needs, with)
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if err != nil {
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return nil, err
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}
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// And what its bindings say, for the half of a connection that is not secret.
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known := knownFor(m, r.Needs, r.Node)
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for _, unsettled := range resources {
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resource, err := ApplySettings(unsettled, with.Settings[m.Module])
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if err != nil {
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return nil, err
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}
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copied := map[string]any{}
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for k, v := range resource {
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copied[k] = v
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}
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// **After settings, and that is the whole reason it is here.** A module's file
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// content is where a setting lands, so a placeholder may only exist once the setting
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// has been put in — filling secrets first would look at content that is not yet what
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// the machine receives.
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if err := intoFile(copied, sealed, m.Module); err != nil {
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return nil, err
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}
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// **Substituted here, not on the machine.** A bound value is not secret — the mesh
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// holds it in the clear — so there is nothing for the host to be the only witness of,
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// and sending it already filled in means the host learns no new field.
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if err := boundInto(copied, known, m.Module); err != nil {
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return nil, err
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}
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copied["id"] = m.Module + "." + fmt.Sprint(resource["id"])
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// A service saying what it reflects names resources within its own module, so those
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// are prefixed too or they would point at nothing.
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//
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// **Unless it already names one.** A module may reflect a file another module put on
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// the machine — the case this exists for is a resolver restarting when the mesh
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// rewrites the names, which are computed by the mesh and belong to its module, not to
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// the daemon's. Written `<module>.<id>`, and a dot is what marks it as already
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// answered: prefixing it again would point at nothing, silently, and the daemon would
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// serve the old names for ever while everything reported success.
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if reflects, ok := resource["restart-on"].([]any); ok {
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var renamed []any
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for _, id := range reflects {
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named := fmt.Sprint(id)
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if strings.Contains(named, ".") {
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renamed = append(renamed, named)
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continue
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}
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renamed = append(renamed, m.Module+"."+named)
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}
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copied["restart-on"] = renamed
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}
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out = append(out, copied)
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}
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}
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return out, nil
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}
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// Contribution is one module telling the answer to a requirement what it needs from it.
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type Contribution struct {
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// From is the module that said it, so the provider and a person reading the file can tell
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// which route belongs to what.
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From string `json:"from"`
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// Node is the machine it said it from, empty when that is this one.
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//
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// A provision answered from anywhere in the mesh has consumers on other machines, and the
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// provider has to know who they are — a database told to create a password and not who for
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// cannot do anything with it. Contributions were node-local until this, which meant the one
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// case that most needed them was the one they did not reach.
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Node string `json:"node,omitempty"`
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// At is where that machine is on the private network, empty when it is not on one or when it
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// is this machine.
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//
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// The mesh knows it and a provider should not have to derive it. A reverse proxy is told
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// *send traffic to this consumer* and has to open a connection — so without this every
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// provider that reaches back to a consumer would have to know how the mesh names machines,
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// which is a convention leaking into every module that implements a provision.
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At string `json:"at,omitempty"`
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// As is who this consumer is: what the provider should call the login it creates.
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//
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// **Said by the mesh rather than invented by the provisioner** (novox/hq 04-ISSUES/023). It
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// used to be neither — the provisioner made a name, and the consumer, which has to present it
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// to authenticate, had no way to learn it. One derivation reaches both ends, so they agree by
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// construction.
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// Omitted when there is none. A contribution that is not a credential grant — a module
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// offering something to another on its own machine — has nobody to be identified to, and a
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// field that is always present and usually empty teaches a reader to ignore it.
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As string `json:"as,omitempty"`
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// Secret is the file on this machine holding that consumer's credential, sealed to it.
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//
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// Named rather than carried, for the same reason the private network's key is: the mesh
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// discarded the value and could not put it here if it wanted to. What is here is where to
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// find it.
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Secret string `json:"secret,omitempty"`
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// Values are the module's own, with settings applied. What the keys mean is agreed by the
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// requirement's name — everything providing `reverse-proxy` understands the same shape, which
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// is what makes swapping one for another cost nothing.
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Values map[string]any `json:"values"`
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}
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// grantPath is where one consumer's sealed credential lands on the providing machine.
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//
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// Suffixed, so the directory can also hold whatever the module writing it keeps there and so a
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// node named like something else in that directory cannot collide with it.
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// One file per consumer, and a consumer is a module on a machine (novox/hq 04-ISSUES/022).
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//
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// Named after both. Named after the machine alone, two modules on one node wrote to one path: the
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// second overwrote the first, and the provisioner — reading a directory — saw one consumer where
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// there were two.
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func grantPath(directory, consumer, module string) string {
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return strings.TrimRight(directory, "/") + "/" + consumer + "." + module + ".secret"
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}
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// contributions collects what every module in this set contributes, by requirement.
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//
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// Ordered by contributing module, because the result becomes a file on a machine and a file whose
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// lines move about is a file that looks changed when nothing changed.
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func (r Resolution) contributions(settings SettingsBy, grants []Grant,
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directories map[string]string) (map[string][]Contribution, error) {
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out := map[string][]Contribution{}
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modules := append([]Manifest{}, r.Modules...)
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sort.Slice(modules, func(i, j int) bool { return modules[i].Module < modules[j].Module })
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|
|
// What consumers on other machines asked for. Merged in with this machine's own, because from
|
|
// the provider's side they are the same thing — somebody wanting something — and a provider
|
|
// that had to read two lists would be a provider that reads one of them.
|
|
sorted := append([]Grant{}, grants...)
|
|
sort.Slice(sorted, func(i, j int) bool {
|
|
if sorted[i].Provision != sorted[j].Provision {
|
|
return sorted[i].Provision < sorted[j].Provision
|
|
}
|
|
if sorted[i].Consumer != sorted[j].Consumer {
|
|
return sorted[i].Consumer < sorted[j].Consumer
|
|
}
|
|
return sorted[i].From < sorted[j].From
|
|
})
|
|
for _, g := range sorted {
|
|
if g.From == "" {
|
|
// As above: nothing on that machine asks for this any more, so the provider is not
|
|
// told about it and withdraws the login on its next pass.
|
|
continue
|
|
}
|
|
out[g.Provision] = append(out[g.Provision], Contribution{
|
|
From: g.From, Node: g.Consumer, At: g.At, Values: g.Values,
|
|
As: ConsumerIdentity(g.Consumer, g.From),
|
|
Secret: grantPath(directories[g.Provision], g.Consumer, g.From),
|
|
})
|
|
}
|
|
for _, m := range modules {
|
|
for _, to := range sortedKeys(m.Contributes) {
|
|
// Settings reach a contribution the same way they reach a file. A route's hostname is
|
|
// exactly the kind of thing that differs between one mesh and the next, and a module
|
|
// that could not have it set would have to be edited to be reused.
|
|
values, err := settle(m.Contributes[to], settings[m.Module], nil,
|
|
m.Module+" contributing to "+to)
|
|
if err != nil {
|
|
return nil, fmt.Errorf("%s contributing to %s: %w", m.Module, to, err)
|
|
}
|
|
out[to] = append(out[to], Contribution{From: m.Module, Values: values})
|
|
}
|
|
}
|
|
return out, nil
|
|
}
|
|
|
|
// receivedFile is the file a provider is given its consumers' contributions in.
|
|
func receivedFile(requirement, path string, given []Contribution) (map[string]any, error) {
|
|
if given == nil {
|
|
// Nobody contributed. The file is still written, empty, rather than left absent: a
|
|
// provider that finds no file cannot tell "nothing asked for me" from "the mesh never
|
|
// wrote it", and the two want completely different responses.
|
|
given = []Contribution{}
|
|
}
|
|
// The note goes *inside* the document, not above it. The first version wrote a `//` header
|
|
// and produced a file that says "do not edit" to a person and fails to parse for the program
|
|
// meant to read it — which is the whole audience.
|
|
body, err := json.MarshalIndent(map[string]any{
|
|
"contributions": 1,
|
|
"requirement": requirement,
|
|
"generated": "by the mesh — do not edit; replaced whenever a module contributing to " +
|
|
requirement + " arrives or leaves",
|
|
"given": given,
|
|
}, "", " ")
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
return map[string]any{
|
|
"id": ReceivedID(requirement), "type": "file", "path": path, "mode": "0644",
|
|
"content": string(body) + "\n",
|
|
}, nil
|
|
}
|
|
|
|
// sortedKeys is map iteration made repeatable, which everything written to a machine needs.
|
|
func sortedKeys[V any](m map[string]V) []string {
|
|
out := make([]string, 0, len(m))
|
|
for k := range m {
|
|
out = append(out, k)
|
|
}
|
|
sort.Strings(out)
|
|
return out
|
|
}
|
|
|
|
// boundFile is what a module is told about something it requires from another machine.
|
|
//
|
|
// Where it is and what the providing module said about using it. **No credential**, and the file
|
|
// says so rather than leaving a reader to wonder whether one was meant to be there — a missing
|
|
// field looks like a bug, and a stated absence looks like a boundary.
|
|
func boundFile(n Needed, path, as string) (map[string]any, error) {
|
|
// A record has no machine and no address. Saying so is the difference between a reader
|
|
// concluding "somewhere with no address" and concluding the mesh failed to fill something in.
|
|
where := any(n.At)
|
|
if n.ByRecord {
|
|
where = "a record in this mesh, not a machine"
|
|
}
|
|
body, err := json.MarshalIndent(map[string]any{
|
|
"binding": 1,
|
|
"provision": n.Name,
|
|
"from": n.From,
|
|
"at": where,
|
|
// Who this module is at the other end. **The half that was missing** (novox/hq
|
|
// 04-ISSUES/023): a consumer was told the address, the port and where its password is,
|
|
// and not the name it must present — which the provisioner had invented.
|
|
"as": as,
|
|
"serves": n.Serves,
|
|
// **Where the credential is, not what it is.** It stopped being true that the mesh
|
|
// cannot issue one when 021 was fixed, and a comment asserting a fact about the mesh that
|
|
// has become false is worse than none — somebody reads it and stops looking.
|
|
"generated": "by the mesh — do not edit; replaced whenever this changes. " +
|
|
"The credential is not here: it is sealed, in the file this module's manifest " +
|
|
"names under `secrets`",
|
|
}, "", " ")
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
return map[string]any{
|
|
"id": BoundID(n.Name), "type": "file", "path": path, "mode": "0644",
|
|
"content": string(body) + "\n",
|
|
}, nil
|
|
}
|
|
|
|
// ContributionsFrom is what one module on this node asked of one requirement, settled.
|
|
//
|
|
// Exported because a provider's grants are assembled from its consumers' resolutions, one machine
|
|
// at a time, and the alternative was for the control plane to reimplement settling.
|
|
//
|
|
// **One module, not one machine** (novox/hq 04-ISSUES/022). This used to take a requirement alone
|
|
// and refuse whenever two modules wanted it — correctly, given what it had: the credential was
|
|
// keyed by node, so the two would have shared one, and sharing is worse than refusing. But the
|
|
// arrangement refused is the ordinary one. A node running eight services against one database is
|
|
// not an edge case; it is what a machine looks like. Now each consumer has its own credential and
|
|
// there is nothing left to refuse.
|
|
func (r Resolution) ContributionsFrom(requirement, module string, settings SettingsBy) (
|
|
map[string]any, bool, error) {
|
|
all, err := r.contributions(settings, nil, nil)
|
|
if err != nil {
|
|
return nil, false, err
|
|
}
|
|
for _, g := range all[requirement] {
|
|
if g.From == module {
|
|
return g.Values, true, nil
|
|
}
|
|
}
|
|
// Nothing on that machine asks for this any more. Said as "not found" rather than as an
|
|
// error: it is how a credential is withdrawn, and the provider removes what nobody asks for.
|
|
return nil, false, nil
|
|
}
|
|
|
|
// here is the module on this same machine that answers a requirement, as a binding.
|
|
//
|
|
// **Only when the provider said something a consumer must know.** That is the line: the original
|
|
// reasoning — a file saying "it is on this node" is a fact nobody needs — is right about the
|
|
// location and wrong about everything beside it. A shell is answered here and there is nothing to
|
|
// say about it. A registry is answered here and the consumer still cannot guess the port.
|
|
//
|
|
// The address is this machine's own name on the private network when it has one, and loopback
|
|
// when it does not — a machine not on the network still reaches itself, and naming it by a name
|
|
// nothing resolves would be worse than naming it by an address that always works.
|
|
func here(r Resolution, requirement string) *Needed {
|
|
for _, m := range r.Modules {
|
|
serves, said := m.Serves[requirement]
|
|
if !said || len(serves) == 0 {
|
|
continue
|
|
}
|
|
at := r.At
|
|
if at == "" {
|
|
at = "127.0.0.1"
|
|
}
|
|
return &Needed{Name: requirement, From: r.Node, At: at, Serves: serves}
|
|
}
|
|
return nil
|
|
}
|
|
|
|
// withMeshNames gives every container in a set the mesh's names.
|
|
//
|
|
// Copied rather than edited in place: these maps come from a module's manifest, and mutating one
|
|
// would change what the catalogue holds for every other machine running that module.
|
|
func withMeshNames(resources []map[string]any, names map[string]string) []map[string]any {
|
|
out := make([]map[string]any, 0, len(resources))
|
|
for _, r := range resources {
|
|
if r["type"] != "container" {
|
|
out = append(out, r)
|
|
continue
|
|
}
|
|
// A container on the machine's own network shares its hosts file already, and a runtime
|
|
// refuses to write one for it. Adding names there would be an argument the runtime
|
|
// rejects, which fails the whole container for something it did not need.
|
|
if network, on := r["network"].(string); on && network == "host" {
|
|
out = append(out, r)
|
|
continue
|
|
}
|
|
|
|
copied := map[string]any{}
|
|
for k, v := range r {
|
|
copied[k] = v
|
|
}
|
|
var given []any
|
|
if already, ok := copied["hosts"].([]any); ok {
|
|
given = append(given, already...)
|
|
}
|
|
for _, name := range sortedKeys(names) {
|
|
given = append(given, name+":"+names[name])
|
|
}
|
|
copied["hosts"] = given
|
|
out = append(out, copied)
|
|
}
|
|
return out
|
|
}
|