Entry Registry
Query and modify registered entries. Access metadata, snapshots, and version history.
Loading
local registry = require("registry")
Entry Structure
{
id = "app.lib:assert", -- string: "namespace:name"
kind = "function.lua", -- string: entry type
meta = {type = "test"}, -- table: searchable metadata
data = {...} -- any: entry payload
}
Get Entry
local entry, err = registry.get("app.lib:assert")
Permission: registry.get on entry ID
Find Entries
local entries, err = registry.find({kind = "function.lua"})
local entries, err = registry.find({kind = "http.endpoint", namespace = "app.api"})
Filter fields match against entry metadata.
Parse ID
local id = registry.parse_id("app.lib:assert")
-- id.ns = "app.lib", id.name = "assert"
Snapshots
Point-in-time view of the registry:
local snap, err = registry.snapshot() -- current state
local snap, err = registry.snapshot_at(5) -- at version 5
Snapshot Methods
| Method | Returns | Description |
|---|---|---|
snap:entries() |
Entry[], error |
All accessible entries |
snap:get(id) |
Entry, error |
Single entry by ID |
snap:find(filter) |
Entry[] |
Filter entries |
snap:namespace(ns) |
Entry[] |
Entries in namespace |
snap:version() |
Version |
Snapshot version |
snap:changes() |
Changes |
Create changeset |
Versions
local version, err = registry.current_version()
local versions, err = registry.versions()
print(version:id()) -- numeric ID
print(version:string()) -- display string
local prev = version:previous() -- previous version or nil
History
local hist, err = registry.history()
local versions, err = hist:versions()
local version, err = hist:get_version(5)
local snap, err = hist:snapshot_at(version)
Changesets
Build and apply modifications:
local snap, err = registry.snapshot()
local changes = snap:changes()
changes:create({
id = "test:new_entry",
kind = "test.kind",
meta = {type = "test"},
data = {config = "value"}
})
changes:update({
id = "test:existing",
kind = "test.kind",
meta = {updated = true},
data = {new_value = true}
})
changes:delete("test:old_entry")
local new_version, err = changes:apply()
Permission: registry.apply for changes:apply()
Changes Methods
| Method | Description |
|---|---|
changes:create(entry) |
Add create operation |
changes:update(entry) |
Add update operation |
changes:delete(id) |
Add delete operation (string or {ns, name}) |
changes:ops() |
Get pending operations |
changes:apply() |
Apply changes, returns new Version |
Apply Version
Roll back or forward to a specific version:
local prev = current_version:previous()
local ok, err = registry.apply_version(prev)
Permission: registry.apply_version
Build Delta
Compute operations to transition between states:
local from = {{id = "test:a", kind = "test", meta = {}, data = {}}}
local to = {{id = "test:b", kind = "test", meta = {}, data = {}}}
local ops, err = registry.build_delta(from, to)
for _, op in ipairs(ops) do
print(op.kind, op.entry.id) -- "entry.create", "entry.update", "entry.delete"
end
Permissions
| Permission | Resource | Description |
|---|---|---|
registry.get |
entry ID | Read entry (also filters find/entries results) |
registry.apply |
- | Apply changeset |
registry.apply_version |
- | Apply/rollback version |
Errors
| Condition | Kind |
|---|---|
| Entry not found | errors.NOT_FOUND |
| Version not found | errors.NOT_FOUND |
| Permission denied | errors.PERMISSION_DENIED |
| Invalid parameter | errors.INVALID |
| No changes to apply | errors.INVALID |
| Registry not available | errors.INTERNAL |
See Error Handling for working with errors.