workflow orchestrator

packages/client/src/api/index.js

@@ -1,43 +1,38 @@
-import { ERROR } from "../state/standardState"
 import { loadRecord } from "./loadRecord"
 import { listRecords } from "./listRecords"
 import { authenticate } from "./authenticate"
 import { saveRecord } from "./saveRecord"
+import { triggerWorkflow } from "./workflow";
+
 
 export const createApi = ({ rootPath = "", setState, getState }) => {
-  const apiCall = method => ({
-    url,
-    body,
-    notFound,
-    badRequest,
-    forbidden,
-  }) => {
-    return fetch(`${rootPath}${url}`, {
+  const apiCall = method => async ({ url, body }) => {
+    const response = await fetch(`${rootPath}${url}`, {
       method: method,
       headers: {
         "Content-Type": "application/json",
       },
       body: body && JSON.stringify(body),
       credentials: "same-origin",
-    }).then(r => {
-      switch (r.status) {
-        case 200:
-          return r.json()
-        case 404:
-          return error(notFound || `${url} Not found`)
-        case 400:
-          return error(badRequest || `${url} Bad Request`)
-        case 403:
-          return error(forbidden || `${url} Forbidden`)
-        default:
-          if (
-            r.status.toString().startsWith("2") ||
-            r.status.toString().startsWith("3")
-          )
-            return r.json()
-          else return error(`${url} - ${r.statusText}`)
-      }
     })
+
+    
+    switch (response.status) {
+      case 200:
+        return response.json()
+      case 404:
+        return error(`${url} Not found`)
+      case 400:
+        return error(`${url} Bad Request`)
+      case 403:
+        return error(`${url} Forbidden`)
+      default:
+        if (response.status >= 200 && response.status < 400) { 
+          return response.json()
+        }
+
+        return error(`${url} - ${response.statusText}`)
+    }
   }
 
   const post = apiCall("POST")
@@ -47,10 +42,9 @@ export const createApi = ({ rootPath = "", setState, getState }) => {
 
   const ERROR_MEMBER = "##error"
   const error = message => {
-    const e = {}
-    e[ERROR_MEMBER] = message
-    setState(ERROR, message)
-    return e
+    const err = { [ERROR_MEMBER]: message }
+    setState("##error_message", message)
+    return err
   }
 
   const isSuccess = obj => !obj || !obj[ERROR_MEMBER]
@@ -72,5 +66,6 @@ export const createApi = ({ rootPath = "", setState, getState }) => {
     listRecords: listRecords(apiOpts),
     authenticate: authenticate(apiOpts),
     saveRecord: saveRecord(apiOpts),
+    triggerWorkflow: triggerWorkflow(apiOpts)
   }
 }

packages/client/src/api/workflow/index.js

@@ -0,0 +1,16 @@
+import Orchestrator, { clientStrategy } from "./orchestrator";
+
+
+export const triggerWorkflow = api => ({ workflow }) => {
+  console.log(workflow);
+  const workflowOrchestrator = new Orchestrator(
+    api,
+    "inst_60dd510_700f7dc06735403e81d5af91072d7241"
+  );
+  workflowOrchestrator.strategy = clientStrategy
+
+  workflowOrchestrator.execute(workflow);
+
+  // hit the API and get the workflow data back
+
+}

packages/client/src/api/workflow/orchestrator.js

@@ -0,0 +1,103 @@
+import get from "lodash/fp/get";
+
+/**
+ * The workflow orhestrator is a class responsible for executing workflows.
+ * It relies on the strategy pattern, which allows composable behaviour to be 
+ * passed into its execute() function. This allows custom execution behaviour based
+ * on where the orchestrator is run.
+ * 
+ */
+export default class Orchestrator {
+  constructor(api, instanceId) {
+    this.api = api
+    this.instanceId = instanceId
+  }
+
+  set strategy(strategy) {
+    this._strategy = strategy
+  }
+
+  async execute(workflowId) {
+    const EXECUTE_WORKFLOW_URL = `/api/${this.instanceId}/workflows/${workflowId}`;
+    const workflow = await this.api.get({ url: EXECUTE_WORKFLOW_URL }) 
+    this._strategy.run({
+      workflow: workflow.definition,
+      api: this.api,
+      instanceId: this.instanceId
+    });
+  }
+}
+
+// Execute a workflow from a running budibase app
+export const clientStrategy = {
+  context: {},
+  bindContextArgs: function(args) {
+    const mappedArgs = { ...args };
+
+    console.log("original args", args)
+
+    // bind the workflow action args to the workflow context, if required
+    for (let arg in args) {
+      const argValue = args[arg];
+      // Means that it's bound to state or workflow context
+      if (argValue.startsWith("$")) {
+        // if value is bound to workflow context.
+        if (argValue.startsWith("$context")) {
+          const path = argValue.replace("$context.", "");
+          // pass in the value from context
+          mappedArgs[arg] = get(path, this.context);  
+        }
+
+        // if the value is bound to state
+        if (argValue.startsWith("$state")) {
+          const path = argValue.match("$context.", "");
+          // pass in the value from context
+          mappedArgs[arg] = get(path, this.context);  
+        }
+      }
+    }
+    return Object.values(mappedArgs);
+  },
+  run: async function({ workflow, api, instanceId }) {
+    const block = workflow.next;
+
+    console.log("Executing workflow block", block);
+
+    if (!block) return;
+
+    // This code gets run in the browser
+    if (block.type === "CLIENT") {
+        if (block.actionId === "SET_STATE") {
+          // get props from the workflow context if required
+          api.setState(...this.bindContextArgs(block.args))
+          // update the context with the data 
+          this.context = {
+            ...this.context,
+            SET_STATE: block.args
+          }
+        }
+    };
+
+    // this workflow block gets executed on the server
+    if (block.type === "SERVER") {
+      const EXECUTE_WORKFLOW_URL = `/api/${instanceId}/workflows/action`
+      const response = await api.post({ 
+        url: EXECUTE_WORKFLOW_URL, 
+        body: {
+          action: block.actionId,
+          args: block.args
+        } 
+      });
+
+      this.context = {
+        ...this.context,
+        [block.actionId]: response 
+      }
+    }
+
+    console.log("workflowContext", this.context)
+
+    // TODO: clean this up, don't pass all those args
+    this.run({ workflow: workflow.next, instanceId, api });
+  }
+}

packages/client/src/state/coreHandlers.js

@@ -68,4 +68,4 @@ export const getNewRecordToState = (coreApi, setState) => ({
   }
 }
 
-const errorHandler = setState => message => setState(ERROR, message)
+const errorHandler = setState => message => setState("##error_message", message)

packages/client/src/state/eventHandlers.js

@@ -33,7 +33,7 @@ export const eventHandlers = (store, rootPath, routeTo) => {
     "List Records": handler(["indexKey", "statePath"], api.listRecords),
     "Save Record": handler(["statePath"], api.saveRecord),
     "Navigate To": handler(["url"], param => routeTo(param && param.url)),
-
+    "Trigger Workflow": handler(["workflow"], api.triggerWorkflow),
     Authenticate: handler(["username", "password"], api.authenticate),
   }
 }

packages/client/src/state/standardState.js

@@ -1 +0,0 @@
-export const ERROR = "##error_message"

packages/client/tests/workflowOrchestrator.spec.js

@@ -0,0 +1,43 @@
+const TEST_WORKFLOW = {
+    "_id": "8ebe79daf1c744c7ab204c0b964e309e",
+    "_rev": "37-94ae573300721c98267cc1d18822c94d",
+    "name": "Workflow",
+    "type": "workflow",
+    "definition": {
+      "next": {
+        "type": "CLIENT",
+        "actionId": "SET_STATE",
+        "args": {
+          "path": "myPath",
+          "value": "foo"
+        },
+        "next": {
+          "type": "SERVER",
+          "actionId": "SAVE_RECORD",
+          "args": {
+             "record": {
+              "modelId": "f452a2b9c3a94251b9ea7be1e20e3b19",
+              "name": "workflowRecord"
+            },
+            "next": {
+              "type": "CLIENT",
+              "actionId": "SET_STATE",
+              "args": {
+                "path": "myPath",
+                "value": "$context.SAVE_RECORD.record.name"
+              },
+            }
+          }
+        }
+      }
+    }
+};
+
+describe("Workflow Orchestrator", () => {
+  it("executes a workflow", () => {
+  });
+
+  it("", () => {
+
+  });
+});

packages/server/src/api/controllers/record.js

@@ -5,6 +5,7 @@ const newid = require("../../db/newid")
 const ajv = new Ajv()
 
 exports.save = async function(ctx) {
+  console.log("THIS INSTANCE", ctx.params.instanceId);
   const db = new CouchDB(ctx.params.instanceId)
   const record = ctx.request.body
 
@@ -43,7 +44,7 @@ exports.save = async function(ctx) {
   record.type = "record"
   const response = await db.post(record)
   record._rev = response.rev
-  ctx.eventPublisher.emit("RECORD_CREATED", record)
+  // ctx.eventPublisher.emit("RECORD_CREATED", record)
 
   ctx.body = record
   ctx.status = 200

packages/server/src/api/controllers/workflow/actions/CUSTOM_JS.js

@@ -0,0 +1,9 @@
+export default async function () {
+  const response = await fetch("www.google.com");
+  console.log(response);
+  console.log("CUSTOM ACTION");
+  return {
+    message: "CUSTOM_WORKFLOW_SCRIPT",
+    response
+  }
+}

packages/server/src/api/controllers/workflow/actions/SAVE_RECORD.js

@@ -0,0 +1,20 @@
+const recordController = require("../../record");
+
+module.exports = async function saveRecord(args) {
+  console.log("SAVING this record", args.record);
+
+  const ctx = {
+    params: {
+      instanceId: "inst_60dd510_700f7dc06735403e81d5af91072d7241",
+    },
+    request: {
+      body: args.record
+    }
+  }
+
+  await recordController.save(ctx);
+
+  return {
+    record: ctx.body
+  }
+}

packages/server/src/api/controllers/workflow/index.js

@@ -1,6 +1,6 @@
-const CouchDB = require("../../db")
+const CouchDB = require("../../../db")
 const Ajv = require("ajv")
-const newid = require("../../db/newid")
+const newid = require("../../../db/newid")
 
 const ajv = new Ajv()
 
@@ -76,6 +76,18 @@ exports.find = async function(ctx) {
   ctx.body = await db.get(ctx.params.id)
 }
 
+exports.executeAction = async function(ctx) {
+  const workflowAction = require(`./actions/${ctx.request.body.action}`);
+  const response = await workflowAction(ctx.request.body.args);
+  ctx.body = response; 
+}
+
+exports.fetchActionScript = async function(ctx) {
+  const workflowAction = require(`./actions/${ctx.action}`);
+  console.log(workflowAction);
+  ctx.body = workflowAction; 
+}
+
 exports.destroy = async function(ctx) {
   const db = new CouchDB(ctx.params.instanceId)
   ctx.body = await db.remove(ctx.params.id, ctx.params.rev)

packages/server/src/api/routes/workflow.js

@@ -6,7 +6,9 @@ const router = Router()
 router
   .get("/api/:instanceId/workflows", controller.fetch)
   .get("/api/:instanceId/workflows/:id", controller.find)
+  .get("/api/:instanceId/workflows/:id/:action", controller.fetchActionScript)
   .post("/api/:instanceId/workflows", controller.create)
+  .post("/api/:instanceId/workflows/action", controller.executeAction)
   .put("/api/:instanceId/workflows", controller.update)
   .delete("/api/:instanceId/workflows/:id/:rev", controller.destroy)