Add the connector contract, reusable nodes and per-port intervals

Connectors are the device-facing node class third parties write, so the
surface they build against is versioned and documented: ConnectorNode carries
a declared contract version, a polling loop that publishes only what changed
and reports health around it, and parameters whose credential fields are
marked x-secret so the editor offers the secrets store instead of a text box.
They are found through the fluksio.node_types entry point group, with the
package's own metadata as the manifest. docs/connectors/ has the contract and
the authoring guide; connector-skeleton/ is a working one to copy.

The controller no longer knows what any node type is: start, stop and
report_health are protocol methods on Node, and the built-ins were migrated to
them first, so the hooks a connector implements are the ones the engine has
been driving all along.

Marking a node reusable moves its source to _lib/ and points the node at it by
name. Other flows instantiate it with their own ports and settings, one fix
reaches all of them, and a shared source still in use cannot be deleted.

Ports gained an interval: an output publishes, and an input wakes its node, at
most every n seconds. State keeps the latest value, so only the delivery is
skipped, and pressing Run is never throttled.

Also fixes autosave sending no version on its first save of a session, which
made every flow saved more than once conflict with itself.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

frontend/src/client/schemas.gen.ts

@@ -343,6 +343,26 @@ export const HistoryPointSchema = {
     description: 'One numeric value a message carried, and when.'
 } as const;
 
+export const LibraryNodeSchema = {
+    properties: {
+        name: {
+            type: 'string',
+            title: 'Name'
+        },
+        used_by: {
+            items: {
+                type: 'string'
+            },
+            type: 'array',
+            title: 'Used By'
+        }
+    },
+    type: 'object',
+    required: ['name'],
+    title: 'LibraryNode',
+    description: 'A node source shared across flows, and who is using it.'
+} as const;
+
 export const MessageSchema = {
     properties: {
         message: {
@@ -398,6 +418,12 @@ export const MessageSpecSchema = {
         dtype: {
             '$ref': '#/components/schemas/DType',
             default: 'float'
+        },
+        interval: {
+            type: 'number',
+            minimum: 0,
+            title: 'Interval',
+            default: 0
         }
     },
     type: 'object',
@@ -408,7 +434,11 @@ export const MessageSpecSchema = {
     the flow name at load time; empty means the port is unbound.
 :param port: The identifier the node function sees. Defaults to the last
     segment of \`\`name\`\`, so unqualified flows read naturally.
-:param dtype: Payload type, validated on every message that passes through.`
+:param dtype: Payload type, validated on every message that passes through.
+:param interval: Deliver at most every this many seconds; 0 is every time.
+    On an output it holds back publishing, on an input it holds back waking
+    the node. The value is never lost — state keeps the latest — only the
+    delivery is skipped.`
 } as const;
 
 export const MessageValueSchema = {
@@ -492,6 +522,17 @@ export const NodeDef_InputSchema = {
             },
             type: 'array',
             title: 'Provides'
+        },
+        source_ref: {
+            anyOf: [
+                {
+                    type: 'string'
+                },
+                {
+                    type: 'null'
+                }
+            ],
+            title: 'Source Ref'
         }
     },
     type: 'object',
@@ -541,6 +582,17 @@ export const NodeDef_OutputSchema = {
             },
             type: 'array',
             title: 'Provides'
+        },
+        source_ref: {
+            anyOf: [
+                {
+                    type: 'string'
+                },
+                {
+                    type: 'null'
+                }
+            ],
+            title: 'Source Ref'
         }
     },
     type: 'object',
@@ -583,12 +635,29 @@ export const NodeStatusPublicSchema = {
                 }
             ],
             title: 'Error'
+        },
+        health: {
+            type: 'string',
+            enum: ['ok', 'degraded', 'down'],
+            title: 'Health',
+            default: 'ok'
+        },
+        health_detail: {
+            anyOf: [
+                {
+                    type: 'string'
+                },
+                {
+                    type: 'null'
+                }
+            ],
+            title: 'Health Detail'
         }
     },
     type: 'object',
     required: ['id'],
     title: 'NodeStatusPublic',
-    description: 'Whether a node loaded, and why not.'
+    description: 'Whether a node loaded, and how its connection is doing.'
 } as const;
 
 export const NodeTypeInfoSchema = {
@@ -614,6 +683,17 @@ export const NodeTypeInfoSchema = {
             type: 'boolean',
             title: 'Has Source',
             default: false
+        },
+        plugin: {
+            anyOf: [
+                {
+                    type: 'string'
+                },
+                {
+                    type: 'null'
+                }
+            ],
+            title: 'Plugin'
         }
     },
     type: 'object',
@@ -733,6 +813,18 @@ export const SecretValueSchema = {
     title: 'SecretValue'
 } as const;
 
+export const ShareRequestSchema = {
+    properties: {
+        lib_name: {
+            type: 'string',
+            title: 'Lib Name'
+        }
+    },
+    type: 'object',
+    required: ['lib_name'],
+    title: 'ShareRequest'
+} as const;
+
 export const TokenSchema = {
     properties: {
         access_token: {

frontend/src/client/sdk.gen.ts

@@ -3,7 +3,7 @@
 import type { CancelablePromise } from './core/CancelablePromise';
 import { OpenAPI } from './core/OpenAPI';
 import { request as __request } from './core/request';
-import type { FlowsReadFlowsResponse, FlowsReadNodeTypesResponse, FlowsReadFlowData, FlowsReadFlowResponse, FlowsSaveFlowData, FlowsSaveFlowResponse, FlowsDeleteFlowData, FlowsDeleteFlowResponse, FlowsPublishFlowData, FlowsPublishFlowResponse, FlowsDiscardDraftData, FlowsDiscardDraftResponse, FlowsRenameFlowData, FlowsRenameFlowResponse, FlowsReadNodeSourceData, FlowsReadNodeSourceResponse, FlowsSaveNodeSourceData, FlowsSaveNodeSourceResponse, FlowsStartFlowData, FlowsStartFlowResponse, FlowsStopFlowData, FlowsStopFlowResponse, FlowsPauseFlowData, FlowsPauseFlowResponse, FlowsResumeFlowData, FlowsResumeFlowResponse, FlowsValidateFlowData, FlowsValidateFlowResponse, FlowsRunFlowData, FlowsRunFlowResponse, FlowsTriggerNodeData, FlowsTriggerNodeResponse, FlowsReadFlowStateData, FlowsReadFlowStateResponse, FlowsReadMessageHistoryData, FlowsReadMessageHistoryResponse, LoginLoginAccessTokenData, LoginLoginAccessTokenResponse, LoginTestTokenResponse, LoginRecoverPasswordData, LoginRecoverPasswordResponse, LoginResetPasswordData, LoginResetPasswordResponse, LoginRecoverPasswordHtmlContentData, LoginRecoverPasswordHtmlContentResponse, PrivateCreateUserData, PrivateCreateUserResponse, SecretsReadSecretsResponse, SecretsSaveSecretData, SecretsSaveSecretResponse, SecretsDeleteSecretData, SecretsDeleteSecretResponse, UsersReadUsersData, UsersReadUsersResponse, UsersCreateUserData, UsersCreateUserResponse, UsersReadUserMeResponse, UsersDeleteUserMeResponse, UsersUpdateUserMeData, UsersUpdateUserMeResponse, UsersUpdatePasswordMeData, UsersUpdatePasswordMeResponse, UsersRegisterUserData, UsersRegisterUserResponse, UsersReadUserByIdData, UsersReadUserByIdResponse, UsersUpdateUserData, UsersUpdateUserResponse, UsersDeleteUserData, UsersDeleteUserResponse, UtilsTestEmailData, UtilsTestEmailResponse, UtilsHealthCheckResponse } from './types.gen';
+import type { FlowsReadFlowsResponse, FlowsReadNodeTypesResponse, FlowsReadLibraryResponse, FlowsDeleteSharedNodeData, FlowsDeleteSharedNodeResponse, FlowsReadFlowData, FlowsReadFlowResponse, FlowsSaveFlowData, FlowsSaveFlowResponse, FlowsDeleteFlowData, FlowsDeleteFlowResponse, FlowsPublishFlowData, FlowsPublishFlowResponse, FlowsDiscardDraftData, FlowsDiscardDraftResponse, FlowsRenameFlowData, FlowsRenameFlowResponse, FlowsReadNodeSourceData, FlowsReadNodeSourceResponse, FlowsSaveNodeSourceData, FlowsSaveNodeSourceResponse, FlowsShareNodeData, FlowsShareNodeResponse, FlowsUnshareNodeData, FlowsUnshareNodeResponse, FlowsStartFlowData, FlowsStartFlowResponse, FlowsStopFlowData, FlowsStopFlowResponse, FlowsPauseFlowData, FlowsPauseFlowResponse, FlowsResumeFlowData, FlowsResumeFlowResponse, FlowsValidateFlowData, FlowsValidateFlowResponse, FlowsRunFlowData, FlowsRunFlowResponse, FlowsTriggerNodeData, FlowsTriggerNodeResponse, FlowsReadFlowStateData, FlowsReadFlowStateResponse, FlowsReadMessageHistoryData, FlowsReadMessageHistoryResponse, LoginLoginAccessTokenData, LoginLoginAccessTokenResponse, LoginTestTokenResponse, LoginRecoverPasswordData, LoginRecoverPasswordResponse, LoginResetPasswordData, LoginResetPasswordResponse, LoginRecoverPasswordHtmlContentData, LoginRecoverPasswordHtmlContentResponse, PrivateCreateUserData, PrivateCreateUserResponse, SecretsReadSecretsResponse, SecretsSaveSecretData, SecretsSaveSecretResponse, SecretsDeleteSecretData, SecretsDeleteSecretResponse, UsersReadUsersData, UsersReadUsersResponse, UsersCreateUserData, UsersCreateUserResponse, UsersReadUserMeResponse, UsersDeleteUserMeResponse, UsersUpdateUserMeData, UsersUpdateUserMeResponse, UsersUpdatePasswordMeData, UsersUpdatePasswordMeResponse, UsersRegisterUserData, UsersRegisterUserResponse, UsersReadUserByIdData, UsersReadUserByIdResponse, UsersUpdateUserData, UsersUpdateUserResponse, UsersDeleteUserData, UsersDeleteUserResponse, UtilsTestEmailData, UtilsTestEmailResponse, UtilsHealthCheckResponse } from './types.gen';
 
 export class FlowsService {
     /**
@@ -32,6 +32,40 @@ export class FlowsService {
         });
     }
     
+    /**
+     * Read Library
+     * The node sources shared across flows, and which nodes use each.
+     * @returns LibraryNode Successful Response
+     * @throws ApiError
+     */
+    public static readLibrary(): CancelablePromise<FlowsReadLibraryResponse> {
+        return __request(OpenAPI, {
+            method: 'GET',
+            url: '/api/v1/flows/library'
+        });
+    }
+    
+    /**
+     * Delete Shared Node
+     * Remove a shared source, as long as no flow still runs it.
+     * @param data The data for the request.
+     * @param data.libName
+     * @returns Message Successful Response
+     * @throws ApiError
+     */
+    public static deleteSharedNode(data: FlowsDeleteSharedNodeData): CancelablePromise<FlowsDeleteSharedNodeResponse> {
+        return __request(OpenAPI, {
+            method: 'DELETE',
+            url: '/api/v1/flows/library/{lib_name}',
+            path: {
+                lib_name: data.libName
+            },
+            errors: {
+                422: 'Validation Error'
+            }
+        });
+    }
+    
     /**
      * Read Flow
      * Read one flow, with the state of its nodes.
@@ -202,6 +236,10 @@ export class FlowsService {
      * The answer comes from compiling the code rather than from the running
      * pipeline: a draft is not deployed, and compiling is both faster and more
      * precise about what the author just typed.
+     *
+     * A shared node writes to the library, so the fix reaches every flow using
+     * it — and that one is live immediately rather than waiting for a publish,
+     * because the copy is not any single flow's to hold back.
      * @param data The data for the request.
      * @param data.name
      * @param data.nodeId
@@ -225,6 +263,55 @@ export class FlowsService {
         });
     }
     
+    /**
+     * Share Node
+     * Move this node's code into the library so other flows can run it too.
+     * @param data The data for the request.
+     * @param data.name
+     * @param data.nodeId
+     * @param data.requestBody
+     * @returns FlowDetail Successful Response
+     * @throws ApiError
+     */
+    public static shareNode(data: FlowsShareNodeData): CancelablePromise<FlowsShareNodeResponse> {
+        return __request(OpenAPI, {
+            method: 'POST',
+            url: '/api/v1/flows/{name}/nodes/{node_id}/share',
+            path: {
+                name: data.name,
+                node_id: data.nodeId
+            },
+            body: data.requestBody,
+            mediaType: 'application/json',
+            errors: {
+                422: 'Validation Error'
+            }
+        });
+    }
+    
+    /**
+     * Unshare Node
+     * Take a private copy of the shared code back into this flow.
+     * @param data The data for the request.
+     * @param data.name
+     * @param data.nodeId
+     * @returns FlowDetail Successful Response
+     * @throws ApiError
+     */
+    public static unshareNode(data: FlowsUnshareNodeData): CancelablePromise<FlowsUnshareNodeResponse> {
+        return __request(OpenAPI, {
+            method: 'POST',
+            url: '/api/v1/flows/{name}/nodes/{node_id}/unshare',
+            path: {
+                name: data.name,
+                node_id: data.nodeId
+            },
+            errors: {
+                422: 'Validation Error'
+            }
+        });
+    }
+    
     /**
      * Start Flow
      * Let the engine run this flow again.

frontend/src/client/types.gen.ts

@@ -105,6 +105,14 @@ export type HTTPValidationError = {
     detail?: Array<ValidationError>;
 };
 
+/**
+ * A node source shared across flows, and who is using it.
+ */
+export type LibraryNode = {
+    name: string;
+    used_by?: Array<(string)>;
+};
+
 export type Message = {
     message: string;
 };
@@ -129,11 +137,16 @@ export type MessageHistory = {
  * :param port: The identifier the node function sees. Defaults to the last
  * segment of ``name``, so unqualified flows read naturally.
  * :param dtype: Payload type, validated on every message that passes through.
+ * :param interval: Deliver at most every this many seconds; 0 is every time.
+ * On an output it holds back publishing, on an input it holds back waking
+ * the node. The value is never lost — state keeps the latest — only the
+ * delivery is skipped.
  */
 export type MessageSpec = {
     name?: string;
     port?: string;
     dtype?: DType;
+    interval?: number;
 };
 
 /**
@@ -162,6 +175,7 @@ export type NodeDef_Input = {
     };
     requires?: Array<MessageSpec>;
     provides?: Array<MessageSpec>;
+    source_ref?: (string | null);
 };
 
 /**
@@ -177,6 +191,7 @@ export type NodeDef_Output = {
     };
     requires?: Array<MessageSpec>;
     provides?: Array<MessageSpec>;
+    source_ref?: (string | null);
 };
 
 /**
@@ -187,14 +202,18 @@ export type NodeSource = {
 };
 
 /**
- * Whether a node loaded, and why not.
+ * Whether a node loaded, and how its connection is doing.
  */
 export type NodeStatusPublic = {
     id: string;
     status?: string;
     error?: (string | null);
+    health?: 'ok' | 'degraded' | 'down';
+    health_detail?: (string | null);
 };
 
+export type health = 'ok' | 'degraded' | 'down';
+
 /**
  * A node type the editor can offer, with its parameter schema.
  */
@@ -206,6 +225,7 @@ export type NodeTypeInfo = {
         [key: string]: unknown;
     };
     has_source?: boolean;
+    plugin?: (string | null);
 };
 
 /**
@@ -246,6 +266,10 @@ export type SecretValue = {
     value: string;
 };
 
+export type ShareRequest = {
+    lib_name: string;
+};
+
 export type Token = {
     access_token: string;
     token_type?: string;
@@ -332,6 +356,14 @@ export type FlowsReadFlowsResponse = (FlowsPublic);
 
 export type FlowsReadNodeTypesResponse = (Array<NodeTypeInfo>);
 
+export type FlowsReadLibraryResponse = (Array<LibraryNode>);
+
+export type FlowsDeleteSharedNodeData = {
+    libName: string;
+};
+
+export type FlowsDeleteSharedNodeResponse = (Message);
+
 export type FlowsReadFlowData = {
     name: string;
 };
@@ -386,6 +418,21 @@ export type FlowsSaveNodeSourceData = {
 
 export type FlowsSaveNodeSourceResponse = (NodeStatusPublic);
 
+export type FlowsShareNodeData = {
+    name: string;
+    nodeId: string;
+    requestBody: ShareRequest;
+};
+
+export type FlowsShareNodeResponse = (FlowDetail);
+
+export type FlowsUnshareNodeData = {
+    name: string;
+    nodeId: string;
+};
+
+export type FlowsUnshareNodeResponse = (FlowDetail);
+
 export type FlowsStartFlowData = {
     name: string;
 };