how to render function execution history as a bpmn diagram

[vigouredelaruse]

this is announcement of a proof of concept that i hacked together that is on the way to displaying the orchestration histories of azure durable functions as annotated bpmn diagrams

consider this refactor of the canonical say hello orchestration

the sayhello activities are selected randomly and the choice is sent as a signal to the orchestration on a timed basis as per

            var gatewayInputs = new GatewayPath[]
            {
                GatewayPath.None,
                GatewayPath.HelloTokyo,
                GatewayPath.HelloLondon,
                GatewayPath.HelloSeattle
            };

            for (int i = 0; i < 5; i++  )
            {
                Random r = new Random();
                int ndx = r.Next(0, 3);

                string instanceId = await starter.StartNewAsync<string>(nameof(Orchestration), gatewayInputs[ndx].ToString());

                log.LogInformation($"Started orchestration with ID = '{instanceId}'.");

            }

consider further this execution history graph for one instance

            executionGraph = JArray.Parse(@"[{
                  ""EventType"": ""ExecutionStarted"",
                  ""Correlation"": null,
                  ""ScheduledStartTime"": null,
                  ""Timestamp"": ""2023-05-12T21:20:00.9598119Z"",
                  ""FunctionName"": ""Orchestration""
                },
                {
                  ""EventType"": ""TaskCompleted"",
                  ""Result"": ""Hello to HelloLondon!"",
                  ""Timestamp"": ""2023-05-12T21:20:14.1661503Z"",
                  ""ScheduledTime"": ""2023-05-12T17:20:10.1905954-04:00"",
                  ""FunctionName"": ""HelloLondon""
                },
                {
                  ""EventType"": ""ExecutionCompleted"",
                  ""OrchestrationStatus"": ""Completed"",
                  ""Result"": [
                    ""Hello to HelloLondon!""
                  ],
                  ""Timestamp"": ""2023-05-12T21:20:24.1778151Z""
                }]");

a somewhat misleading diagram of the orchestration looks like this

the first day output of the hack in question looks like the below

this required careful attribute name matching between camunda modeller diagram elements and function names in the execution graph as per

special considerations
the first day implementation is blindingly slow on my imsa rewind playback machine likely due to naive durable functions history querying

when implemented as a http trigger function the output can be content negotiated into json (your own reader) or xml (many bpmn readers)

now that i see this is pratical i will be integrating it into an earth observation tool i'm building which means the code will inexorably progress towards

• a nuget package
• sketching a usable query surface for filtering orchestration histories
• perhaps a special driver implementation for querying storage providers directly in case of adverse performance

best regards