Allow a State to set a value in Credentials for subsequent states

CHANGELOG.md

@@ -8,6 +8,7 @@ This project adheres to [Semantic Versioning](http://semver.org/).
 
 ### Added
 - Implement `ReferencePath#get` ([#144](https://github.com/ManageIQ/floe/pull/144))
+- Allow a State to set a value in Credentials for subsequent states ([#145](https://github.com/ManageIQ/floe/pull/145))
 
 ## [0.6.1] - 2023-11-21
 ### Fixed

README.md

@@ -51,6 +51,38 @@ You can provide that at runtime via the `--credentials` parameter:
 bundle exec ruby exe/floe --workflow my-workflow.asl --credentials='{"roleArn": "arn:aws:iam::111122223333:role/LambdaRole"}'
 ```
 
+If you need to set a credential at runtime you can do that by using the `"ResultPath": "$.Credentials"` directive, for example to user a username/password to login and get a Bearer token:
+
+```
+bundle exec ruby exe/floe --workflow my-workflow.asl --credentials='{"username": "user", "password": "pass"}'
+```
+
+```json
+{
+  "StartAt": "Login",
+  "States": {
+    "Login": {
+      "Type": "Task",
+      "Resource": "docker://login:latest",
+      "Credentials": {
+        "username.$": "$.username",
+        "password.$": "$.password"
+      },
+      "ResultPath": "$.Credentials",
+      "Next": "DoSomething"
+    },
+    "DoSomething": {
+      "Type": "Task",
+      "Resource": "docker://do-something:latest",
+      "Credentials": {
+        "token.$": "$.bearer_token"
+      },
+      "End": true
+    }
+  }
+}
+```
+
 ### Ruby Library
 
 ```ruby

examples/set-credential.asl

@@ -0,0 +1,26 @@
+{
+  "Comment": "An example showing how to set a credential.",
+  "StartAt": "Login",
+  "States": {
+    "Login": {
+      "Type": "Task",
+      "Resource": "docker://docker.io/agrare/echo:latest",
+      "Parameters": {
+        "ECHO": "TOKEN"
+      },
+      "ResultPath": "$.Credentials",
+      "ResultSelector": {
+        "bearer_token.$": "$.echo"
+      },
+      "Next": "DoSomething"
+    },
+    "DoSomething": {
+      "Type": "Task",
+      "Resource": "docker://docker.io/agrare/hello-world:latest",
+      "Credentials": {
+        "bearer_token.$": "$.bearer_token"
+      },
+      "End": true
+    }
+  }
+}

lib/floe.rb

@@ -25,6 +25,7 @@
 require_relative "floe/workflow/state"
 require_relative "floe/workflow/states/choice"
 require_relative "floe/workflow/states/fail"
+require_relative "floe/workflow/states/input_output_mixin"
 require_relative "floe/workflow/states/map"
 require_relative "floe/workflow/states/non_terminal_mixin"
 require_relative "floe/workflow/states/parallel"

lib/floe/workflow/path.rb

@@ -9,6 +9,8 @@ def value(payload, context, input = {})
         end
       end
 
+      attr_reader :payload
+
       def initialize(payload)
         @payload = payload
 
@@ -28,10 +30,6 @@ def value(context, input = {})
 
         results.count < 2 ? results.first : results
       end
-
-      private
-
-      attr_reader :payload
     end
   end
 end

lib/floe/workflow/states/input_output_mixin.rb

@@ -0,0 +1,31 @@
+# frozen_string_literal: true
+
+module Floe
+  class Workflow
+    module States
+      module InputOutputMixin
+        def process_input(input)
+          input = input_path.value(context, input)
+          input = parameters.value(context, input) if parameters
+          input
+        end
+
+        def process_output(input, results)
+          return input if results.nil?
+          return if output_path.nil?
+
+          results = result_selector.value(context, results) if @result_selector
+          if result_path.payload.start_with?("$.Credentials")
+            credentials = result_path.set(workflow.credentials, results)["Credentials"]
+            workflow.credentials.merge!(credentials)
+            output = input
+          else
+            output = result_path.set(input, results)
+          end
+
+          output_path.value(context, output)
+        end
+      end
+    end
+  end
+end

lib/floe/workflow/states/pass.rb

@@ -4,6 +4,7 @@ module Floe
   class Workflow
     module States
       class Pass < Floe::Workflow::State
+        include InputOutputMixin
         include NonTerminalMixin
 
         attr_reader :end, :next, :result, :parameters, :input_path, :output_path, :result_path
@@ -25,12 +26,11 @@ def initialize(workflow, name, payload)
 
         def start(input)
           super
-          output = input_path.value(context, input)
-          output = result_path.set(output, result) if result && result_path
-          output = output_path.value(context, output)
 
+          input = process_input(input)
+
+          context.output     = process_output(input, result)
           context.next_state = end? ? nil : @next
-          context.output     = output
         end
 
         def running?

lib/floe/workflow/states/task.rb

@@ -4,6 +4,7 @@ module Floe
   class Workflow
     module States
       class Task < Floe::Workflow::State
+        include InputOutputMixin
         include NonTerminalMixin
 
         attr_reader :credentials, :end, :heartbeat_seconds, :next, :parameters,
@@ -49,7 +50,7 @@ def finish
 
           if success?
             output = parse_output(output)
-            context.state["Output"] = process_output!(output)
+            context.state["Output"] = process_output(context.input.dup, output)
             context.next_state      = next_state
           else
             error = parse_error(output)
@@ -126,12 +127,6 @@ def fail_workflow!(error)
           context.state["Error"] = context.output["Error"]
         end
 
-        def process_input(input)
-          input = input_path.value(context, input)
-          input = parameters.value(context, input) if parameters
-          input
-        end
-
         def parse_error(output)
           return if output.nil?
           return output if output.kind_of?(Hash)
@@ -150,16 +145,6 @@ def parse_output(output)
           nil
         end
 
-        def process_output!(results)
-          output = context.input.dup
-          return output if results.nil?
-          return if output_path.nil?
-
-          results = result_selector.value(context, results) if result_selector
-          output  = result_path.set(output, results)
-          output_path.value(context, output)
-        end
-
         def next_state
           end? ? nil : @next
         end

spec/workflow/states/pass_spec.rb

@@ -2,21 +2,20 @@
   let(:input)    { {} }
   let(:ctx)      { Floe::Workflow::Context.new(:input => input) }
   let(:state)    { workflow.current_state }
-  let(:workflow) do
-    make_workflow(
-      ctx, {
-        "PassState"    => {
-          "Type"       => "Pass",
-          "Result"     => {
-            "foo" => "bar",
-            "bar" => "baz"
-          },
-          "ResultPath" => "$.result",
-          "Next"       => "SuccessState"
+  let(:workflow) { make_workflow(ctx, payload) }
+  let(:payload)  do
+    {
+      "PassState"    => {
+        "Type"       => "Pass",
+        "Result"     => {
+          "foo" => "bar",
+          "bar" => "baz"
         },
-        "SuccessState" => {"Type" => "Succeed"}
-      }
-    )
+        "ResultPath" => "$.result",
+        "Next"       => "SuccessState"
+      },
+      "SuccessState" => {"Type" => "Succeed"}
+    }
   end
 
   describe "#end?" do
@@ -31,5 +30,28 @@
       expect(ctx.output["result"]).to include({"foo" => "bar", "bar" => "baz"})
       expect(ctx.next_state).to eq("SuccessState")
     end
+
+    context "with a ResultPath setting a Credential" do
+      let(:payload) do
+        {
+          "PassState"    => {
+            "Type"       => "Pass",
+            "Result"     => {
+              "user"     => "luggage",
+              "password" => "1234"
+            },
+            "ResultPath" => "$.Credentials",
+            "Next"       => "SuccessState"
+          },
+          "SuccessState" => {"Type" => "Succeed"}
+        }
+      end
+
+      it "sets the result in Credentials" do
+        state.run_nonblock!
+        expect(workflow.credentials).to include({"user" => "luggage", "password" => "1234"})
+        expect(ctx.next_state).to eq("SuccessState")
+      end
+    end
   end
 end

spec/workflow/states/task_spec.rb

@@ -98,6 +98,22 @@
             "ip_addrs" => ["192.168.1.2"]
           )
         end
+
+        context "setting a Credential" do
+          let(:workflow) { make_workflow(ctx, {"State" => {"Type" => "Task", "Resource" => resource, "ResultPath" => "$.Credentials", "End" => true}}) }
+
+          it "inserts the response into the workflow credentials" do
+            expect_run_async(input, :output => "{\"token\": \"shhh!\"}")
+
+            workflow.current_state.run_nonblock!
+
+            expect(workflow.credentials).to include("token" => "shhh!")
+            expect(ctx.output).to eq(
+              "foo" => {"bar" => "baz"},
+              "bar" => {"baz" => "foo"}
+            )
+          end
+        end
       end
 
       context "OutputPath" do