message_context type

This reference documents the Slack types at the platform level. Their availability and structure may differ in each SDK

Type: slack#/types/message_context

Property	Type	Description
default	The type that is being described.	An optional parameter default value.
description	string	An optional parameter description.
examples	An array of the type being described.	An optional list of examples.
hint	string	An optional parameter hint.
title	string	An optional parameter title.
type	string	String that defines the parameter type.

The message_context type is used in the ReplyInThread Slack function as the target message you want to reply to.

For example, let's say you have a workflow step that uses the SendMessage function. If you want to send a reply to that message in a follow-on step that calls the ReplyInThread function, pass the return value from the first step into the message_context parameter of ReplyInThread.

Here's a brief example:

JSON manifest

// ...
"message_context": {
  "type": "slack#/types/message_context"
}
// ...

Deno Slack SDK

// Send a message to channel with ID C123456
const msgStep = GreetingWorkflow.addStep(Schema.slack.functions.SendMessage, {
  channel_id: "C123456",
  message: "This is a message to the channel.",
});

// Send a message as an in-thread reply to the above message by passing
// the outputs' message_context property
GreetingWorkflow.addStep(Schema.slack.functions.ReplyInThread, {
  message_context: msgStep.outputs.message_context,
  message: "This is a threaded reply to the above message.",
});

You can also construct and deconstruct the message_context property as you see fit in your app. Here is what comprises message_context:

Property	Type	Description	Required
message_ts	Schema.slack.types.message_ts	A Slack-specific hash/timestamp necessary for referencing events like messages in Slack.	Required
channel_id	Schema.slack.types.channel_id	The ID of the channel where the message is posted.	Optional

Any individual property on message_context could be referenced too. See the below example where we pass message_context.message_ts to the trigger_ts property:

//...

const message = CreateSurveyWorkflow.addStep(
  Schema.slack.functions.ReplyInThread,
  {
    message_context: {
      channel_id: CreateSurveyWorkflow.inputs.channel_id,
      message_ts: CreateSurveyWorkflow.inputs.parent_ts,
    },
    message:
      `Your feedback is requested – <${trigger.outputs.trigger_url}|survey now>!`,
  },
);

CreateSurveyWorkflow.addStep(SaveSurveyFunctionDefinition, {
  channel_id: CreateSurveyWorkflow.inputs.channel_id,
  parent_ts: CreateSurveyWorkflow.inputs.parent_ts,
  reactor_id: CreateSurveyWorkflow.inputs.reactor_id,
  trigger_ts: message.outputs.message_context.message_ts, //Here we reference message_ts from message_context
  trigger_id: trigger.outputs.trigger_id,
  survey_stage: "SURVEY",
});

//...