Contract: the seat mesh-module-assigner gains the read verb placement

Builds: design 47 G A-62 (§704, §402)

Claude-Session: https://claude.ai/code/session_01NcbgfGKaxw984XyAPfLm4h

go/seats/meshmoduleassigner/contract.go

@@ -20,6 +20,7 @@ const (
 	VerbPropose     = "propose"
 	VerbWithdraw    = "withdraw"
 	VerbAgain       = "again"
+	VerbPlacement   = "placement"
 )
 
 const (
@@ -31,7 +32,7 @@ const (
 
 // Verbs is every verb the seat serves, in its definition's order: a new copy each call.
 func Verbs() []string {
-	return []string{VerbAssignments, VerbProposals, VerbPropose, VerbWithdraw, VerbAgain}
+	return []string{VerbAssignments, VerbProposals, VerbPropose, VerbWithdraw, VerbAgain, VerbPlacement}
 }
 
 // Events is every event published on the seat's subject: a new copy each call.
@@ -401,6 +402,12 @@ type Holding struct {
 	Site   string `json:"site,omitempty"`
 }
 
+// ModulePlacement is the nodes that run a module from one watched branch.
+type ModulePlacement struct {
+	Branch string   `json:"branch"`
+	Nodes  []string `json:"nodes"`
+}
+
 // NodeDecided is what a person decides of a node; no secret and no key material.
 type NodeDecided struct {
 	Account          string `json:"account,omitempty"`
@@ -624,6 +631,18 @@ type AgainInput struct {
 // AgainAnswer is what again answers.
 type AgainAnswer = map[string]any
 
+// PlacementInput is what placement takes.
+type PlacementInput struct {
+	// the module
+	Module string `json:"module"`
+}
+
+// PlacementAnswer is what placement answers.
+type PlacementAnswer struct {
+	// one per branch, the nodes that run the module from it
+	Placements []ModulePlacement `json:"placements"`
+}
+
 // AssignmentsProposedEvent is the body of the event assignments-proposed.
 type AssignmentsProposedEvent = AssignmentsEvent
 

seats/mesh-module-assigner/seat.json

@@ -154,6 +154,39 @@
         "type": "object",
         "description": "what was judged or asked again"
       }
+    },
+    {
+      "name": "placement",
+      "description": "Read the placements of one module as the assignments rows hold them: for each watched branch a node runs it from, the nodes that run it from there.",
+      "optional": true,
+      "input": {
+        "properties": {
+          "module": {
+            "description": "the module",
+            "type": "string"
+          }
+        },
+        "required": [
+          "module"
+        ],
+        "type": "object"
+      },
+      "answer": {
+        "properties": {
+          "placements": {
+            "type": "array",
+            "items": {
+              "$ref": "#/defs/ModulePlacement"
+            },
+            "description": "one per branch, the nodes that run the module from it"
+          }
+        },
+        "required": [
+          "placements"
+        ],
+        "type": "object"
+      },
+      "class": "read"
     }
   ],
   "events": [
@@ -1009,6 +1042,25 @@
         "scope",
         "holders"
       ]
+    },
+    "ModulePlacement": {
+      "type": "object",
+      "description": "the nodes that run a module from one watched branch",
+      "properties": {
+        "branch": {
+          "type": "string"
+        },
+        "nodes": {
+          "type": "array",
+          "items": {
+            "type": "string"
+          }
+        }
+      },
+      "required": [
+        "branch",
+        "nodes"
+      ]
     }
   }
 }

ts/seats/meshmoduleassigner/index.d.ts

@@ -10,6 +10,7 @@ export declare const verbs: {
   readonly propose: "propose";
   readonly withdraw: "withdraw";
   readonly again: "again";
+  readonly placement: "placement";
 };
 
 export declare const events: {
@@ -143,6 +144,12 @@ export interface Holding {
   "site"?: string;
 }
 
+/** the nodes that run a module from one watched branch */
+export interface ModulePlacement {
+  "branch": string;
+  "nodes": string[];
+}
+
 /** what a person decides of a node; no secret and no key material */
 export interface NodeDecided {
   "account"?: string;
@@ -353,6 +360,18 @@ export interface AgainInput {
 /** is what again answers. */
 export type AgainAnswer = Record<string, unknown>;
 
+/** is what placement takes. */
+export interface PlacementInput {
+  /** the module */
+  "module": string;
+}
+
+/** is what placement answers. */
+export interface PlacementAnswer {
+  /** one per branch, the nodes that run the module from it */
+  "placements": ModulePlacement[];
+}
+
 /** is the body of the event assignments-proposed. */
 export type AssignmentsProposedEvent = AssignmentsEvent;
 

ts/seats/meshmoduleassigner/index.js

@@ -10,6 +10,7 @@ export const verbs = {
   propose: "propose",
   withdraw: "withdraw",
   again: "again",
+  placement: "placement",
 };
 
 export const events = {