jschoubben
96a37f58ca
The controller's declared-config mirror never held de-spiegel's keys, and Resolve skipped an assigned module it held no declarations of, silently: de-spiegel stayed held on novox with its values set. Declarations now come from the indexer's trunk manifest with the wanted build's laid over it per node; which module runs where from the seat mesh-placement alone. A placed module with no readable manifest is listed as unresolved with why, logged, and keeps its last resolved values.
4.8 KiB
mesh-config
Holds the mesh-config seat: the owner of every config value (novox/hq ADR 0348 §9, design 57 K3). Go, one
binary (cmd/mesh-config), served by a runtime of its own on its own bus account (runs-as), so that its
account alone writes its buckets.
What it keeps
mesh-config_values: each value set, keyed by its level:mesh.<key>(mesh config),node.<node>.<key>(node config) andmodule.<node>.<module>.<key>(a module's own value on one node), each with who set it, through which account, why and when.mesh-config_resolved: each assigned module's value for each key it declares on its node, keyed<node>.<module>.<key>, with its source:default,mesh,node,module, orunsetfor a required value nothing sets.mesh-config_predefined: the list of predefined keys, published from the list the controller kept (its mirrormesh-controller.predefined), the newest trunk build winning. A newer list dropping a key that still holds a value at the mesh or a node is withheld, and every listing says why, until that value is cleared.mesh-config_proposals: each value proposed for the operator's Approve, whole, with the value stored at its level when it was proposed (what the operator is shown the change against), who proposed it, why, and what came of it.- the log
history: every set, clear and move of resolved values, with the proven caller and why.
How a value resolves
For every module the seat mesh-placement places on a node (mesh-delivery-assigner.placement), from the module's
own manifests as the delivery built them, never from the controller (issue 1953): the trunk's, which the indexer's
modules.<module> names in its manifests by digest (mesh-delivery-indexer.modules, .manifests), with the build the
node's want names (mesh-delivery-assigner.wants, the builder's mesh-delivery-builder.builds naming its manifest)
laid over it key by key on that node. So a module from its own repository resolves as a catalogue module does. A placed
module none of whose manifests can be read is listed under unresolved with why and said in the log, and keeps the
values last resolved for it. Then: the manifest's default; mesh config for the predefined key the value falls back
to; node config for that key on the node; the module's own value on that node, the most specific winning. A value
naming no predefined key resolves from its default and the module's own value only (ADR 0348 §2). It resolves at
start, whenever a placement, a want or a trunk module moves, and every five minutes, writing only the values that moved.
The verb
mesh-config.config with action list (the default), set, clear or history, narrowed by module, node
and key. A set or a clear names one level (no module and no node for mesh config, a node for node config, both
for a module's own value), needs why, refuses a key the module or the predefined list does not declare (naming
the declared keys), validates the value, writes it and the resolved values it moves, keeps it in the history and
the controller's hand-act log, raises config-changed, and answers with each module on each node whose value
moved. It opens no walk. A trusted value is taken only from the controller, which carries it from its terminal and
names who gave it in by, or on the operator's Approve of a proposal.
Proposing a value (ADR 0348 §8, design 57 K4)
action propose (with value, or clear) judges the value as a set would, keeps it in mesh-config_proposals,
and asks the operator under mesh-config's own name on the operator-channel seat (its own grant, from uses, and
its own cap of three open asks; the same change twice is refused, and a newer proposal for the same level and key
replaces the older). The ask says the level, the key and the value, exact where who answers is proven, and that,
approved, it takes effect at once on every node it reaches; Approve and Decline are both at the level approve and
each binds the proposal's level, key, value and the value it was shown against. On the answer mesh-config reads
the router's own record of its ask and holds the warrant to the ask composed again from the proposal; it refuses,
and sets nothing, when the proposal or the value stored at the level changed since. An Approve that holds sets the
value as a set does, keeps who approved it beside the value (approved), and asks the controller to record the
warrant in its hand-act log. A Decline, an expiry or the router's refusal sets nothing. action proposals lists
them, newest first; with proposal, one read whole, with whether the router's ask is the one composed from it.
Files it does not know
Each directory or archive this module declares says how it treats a file it did not write (ADR 0422, ADR 0416).
${dir:state}: everything in it is the program's; the mesh moves nothing out (ADR 0422 §2).