Creating scheduled triggers
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Invoke a workflow at specific time intervals
Scheduled triggers are an automatic type of trigger. This means that once the trigger is created, they do not require any user input.
Use a scheduled trigger if you need a workflow to kick off after a delay or on an hourly, daily, weekly, or annual cadence.
Create a scheduled trigger
Triggers can be added to workflows in two ways:
-
You can add triggers with the CLI. These static triggers are created only once. You create them with the Slack CLI, attach them to your app's workflow, and that's that. The trigger is defined within a trigger file.
-
You can add triggers at runtime. These dynamic triggers are created at any step of a workflow so they can incorporate data acquired from other workflow steps. The trigger is defined within a function file.
- Create a scheduled trigger with the CLI
- Create a scheduled trigger at runtime
Use slack trigger --help
to easily access information on the trigger
command's flags and subcommands.
The triggers you create when running locally (with the slack run
command) will not work when you deploy your app in production (with the slack deploy
command). You'll need to create
any triggers again with the CLI.
Create the trigger file
To create a scheduled trigger with the CLI, you'll need to create a trigger file. The trigger file contains the payload you used to define your trigger.
Create a TypeScript trigger file within your app's folder with the following form:
import { Trigger } from "deno-slack-api/types.ts";
import { ExampleWorkflow } from "../workflows/example_workflow.ts";
import { TriggerTypes } from "deno-slack-api/mod.ts";
const trigger: Trigger<typeof ExampleWorkflow.definition> = {
// your TypeScript payload
};
export default trigger;
Your TypeScript payload consists of the parameters needed for your own use case. Below is the trigger file from the Message Translator app:
// triggers/daily_maintenance_job.ts
import { Trigger } from "deno-slack-sdk/types.ts";
import workflowDef from "../workflows/maintenance_job.ts";
import { TriggerTypes } from "deno-slack-api/mod.ts";
/**
* A trigger that periodically starts the "maintenance-job" workflow.
*/
const trigger: Trigger<typeof workflowDef.definition> = {
type: TriggerTypes.Scheduled,
name: "Trigger a scheduled maintenance job",
workflow: `#/workflows/${workflowDef.definition.callback_id}`,
inputs: {},
schedule: {
// Schedule the first execution 60 seconds from when the trigger is created
start_time: new Date(new Date().getTime() + 60000).toISOString(),
end_time: "2037-12-31T23:59:59Z",
frequency: { type: "daily", repeats_every: 1 },
},
};
export default trigger;
Use the trigger create
command
Once you have created a trigger file, use the following command to create the scheduled trigger:
slack trigger create --trigger-def "path/to/trigger.ts"
If you have not used the slack triggers create
command to create a trigger prior to running the slack run
command, you will receive a prompt in the Slack CLI to do so.
Your app needs to have the triggers:write
scope to use a trigger at runtime. Include the scope within your app's manifest.
The logic of a runtime trigger lies within a function's TypeScript code. Within your functions
folder, you'll have the functions that are the steps making up your workflow. Within this folder is where you can create a trigger within the relevant <function>.ts
file.
When you create a runtime trigger, you can leverage inputs
acquired from functions within the workflow. Provide the workflow definition to get additional typing for the workflow and inputs fields.
Create a scheduled trigger at runtime using the client.workflows.triggers.create
method within the relevant function
file.
const triggerResponse = await client.workflows.triggers.create<typeof ExampleWorkflow.definition>({
// your TypeScript payload
});
Your TypeScript payload consists of the parameters needed for your own use case. Below is the function file with a TypeScript payload for a scheduled trigger from the Daily Channel Topic app:
// functions/create_scheduled_trigger.ts
import { SlackAPI } from "deno-slack-api/mod.ts";
import { DefineFunction, Schema, SlackFunction } from "deno-slack-sdk/mod.ts";
import { TriggerTypes } from "deno-slack-api/mod.ts";
export const CreateScheduledTrigger = DefineFunction({
title: "Create a scheduled trigger",
callback_id: "create_scheduled_trigger",
source_file: "functions/create_scheduled_trigger.ts",
input_parameters: {
properties: {
channel_id: {
description: "The ID of the Channel to create a schedule for",
type: Schema.slack.types.channel_id,
},
},
required: ["channel_id"],
},
output_parameters: {
properties: {
trigger_id: {
description: "The ID of the trigger created by the Slack API",
type: Schema.types.string,
},
},
required: ["trigger_id"],
},
});
export default SlackFunction(
CreateScheduledTrigger,
async ({ inputs, token }) => {
console.log(`Creating scheduled trigger to update daily topic`);
const client = SlackAPI(token, {});
const scheduleDate = new Date();
// Start schedule 1 minute in the future. Start_time must always be in the future.
scheduleDate.setMinutes(scheduleDate.getMinutes() + 1);
// triggers/sample_scheduled_update_topic.txt has a JSON example of the payload
const scheduledTrigger = await client.workflows.triggers.create({
name: `Channel ${inputs.channel_id} Schedule`,
workflow: "#/workflows/scheduled_update_topic",
type: TriggerTypes.Scheduled,
inputs: {
channel_id: { value: inputs.channel_id },
},
schedule: {
start_time: scheduleDate.toUTCString(),
frequency: {
type: "daily",
repeats_every: 1,
},
},
});
if (!scheduledTrigger.trigger) {
return {
error: "Trigger could not be created",
};
}
console.log("scheduledTrigger has been created");
return {
outputs: { trigger_id: scheduledTrigger.trigger.id },
};
},
);
Scheduled trigger parameters
Field | Description | Required? |
---|---|---|
type | The type of trigger: TriggerTypes.Scheduled | Required |
name | The name of the trigger | Required |
workflow | Path to workflow that the trigger initiates | Required |
schedule | When and how often the trigger will activate. See the schedule object below | Required |
description | The description of the trigger | Optional |
inputs | The inputs provided to the workflow. See the inputs object below | Optional |
Scheduled triggers are not interactive. Use a link trigger to take advantage of interactivity.
The inputs
object
The inputs
of a trigger map to the inputs of a workflow. You can pass any value as an input.
There is also a specific input value that contains information about the trigger. Pass this value to provide trigger information to your workflows!
Fields that take the form of data.VALUE
can be referenced in the form of TriggerContextData.Shortcut.VALUE
Referenced field | Type | Description |
---|---|---|
TriggerContextData.Scheduled.user_id | string | A unique identifier for the user who created the trigger. |
TriggerContextData.Scheduled.event_timestamp | timestamp | A Unix timestamp in seconds indicating when this event was dispatched. |
The following snippet shows a user_id
input being set with a value of TriggerContextData.Scheduled.user_id
, representing the user who created the trigger.
...
inputs: {
user_id: {
value: TriggerContextData.Scheduled.user_id
}
},
...
The schedule
object
Field | Description | Required? |
---|---|---|
start_time | ISO date string of the first scheduled trigger | Required |
timezone | Timezone string to use for scheduling | Optional |
frequency | Details on what cadence trigger will activate. See the frequency object below | Optional |
occurrence_count | The maximum number of times trigger will run | Optional |
end_time | If set, this trigger will not run past the provided ISO date string | Optional |
The frequency
object
One-time triggers
Field | Description | Required? |
---|---|---|
type | How often the trigger will activate: once | Required |
repeats_every | How often the trigger will repeat, respective to frequency.type | Optional |
on_week_num | The nth week of the month the trigger will repeat | Optional |
Example one-time trigger
import { TriggerTypes } from "deno-slack-api/mod.ts";
import { ScheduledTrigger } from "deno-slack-api/typed-method-types/workflows/triggers/scheduled.ts";
import { ExampleWorkflow } from "../workflows/example_workflow.ts";
const schedule: ScheduledTrigger<typeof ExampleWorkflow.definition> = {
name: "Sample",
type: TriggerTypes.Scheduled,
workflow: `#/workflows/${ExampleWorkflow.definition.callback_id}`,
inputs: {},
schedule: {
// Starts 60 seconds after creation
start_time: new Date(new Date().getTime() + 60000).toISOString(),
timezone: "asia/kolkata",
frequency: {
type: "once",
},
},
};
export default schedule;
Hourly triggers
Field | Description | Required? |
---|---|---|
type | How often the trigger will activate: hourly | Required |
repeats_every | How often the trigger will repeat, respective to frequency.type | Required |
on_week_num | The nth week of the month the trigger will repeat | Optional |
Example hourly trigger
import { TriggerTypes } from "deno-slack-api/mod.ts";
import { ScheduledTrigger } from "deno-slack-api/typed-method-types/workflows/triggers/scheduled.ts";
import { ExampleWorkflow } from "../workflows/example_workflow.ts";
const schedule: ScheduledTrigger<typeof ExampleWorkflow.definition> = {
name: "Sample",
type: TriggerTypes.Scheduled,
workflow: `#/workflows/${ExampleWorkflow.definition.callback_id}`,
inputs: {},
schedule: {
// Starts 60 seconds after creation
start_time: new Date(new Date().getTime() + 60000).toISOString(),
end_time: "2040-05-01T14:00:00Z",
frequency: {
type: "hourly",
repeats_every: 2,
},
},
};
export default schedule;
Daily triggers
Field | Description | Required? |
---|---|---|
type | How often the trigger will activate: daily | Required |
repeats_every | How often the trigger will repeat, respective to frequency.type | Required |
on_week_num | The nth week of the month the trigger will repeat | Optional |
Example daily trigger
import { TriggerTypes } from "deno-slack-api/mod.ts";
import { ScheduledTrigger } from "deno-slack-api/typed-method-types/workflows/triggers/scheduled.ts";
import { ExampleWorkflow } from "../workflows/example_workflow.ts";
const schedule: ScheduledTrigger<typeof ExampleWorkflow.definition> = {
name: "Sample",
type: TriggerTypes.Scheduled,
workflow: `#/workflows/${ExampleWorkflow.definition.callback_id}`,
inputs: {},
schedule: {
// Starts 60 seconds after creation
start_time: new Date(new Date().getTime() + 60000).toISOString(),
end_time: "2040-05-01T14:00:00Z",
occurrence_count: 3,
frequency: { type: "daily" },
},
};
export default schedule;
Weekly triggers
Field | Description | Required? |
---|---|---|
type | How often the trigger will activate: weekly | Required |
on_days | The days of the week the trigger should activate on | Required |
repeats_every | How often the trigger will repeat, respective to frequency.type | Required |
on_week_num | The nth week of the month the trigger will repeat | Optional |
Example weekly trigger
import { TriggerTypes } from "deno-slack-api/mod.ts";
import { ScheduledTrigger } from "deno-slack-api/typed-method-types/workflows/triggers/scheduled.ts";
import { ExampleWorkflow } from "../workflows/example_workflow.ts";
const schedule: ScheduledTrigger<typeof ExampleWorkflow.definition> = {
name: "Sample",
type: TriggerTypes.Scheduled,
workflow: `#/workflows/${ExampleWorkflow.definition.callback_id}`,
inputs: {},
schedule: {
// Starts 60 seconds after creation
start_time: new Date(new Date().getTime() + 60000).toISOString(),
frequency: {
type: "weekly",
repeats_every: 3,
on_days: ["Friday", "Monday"],
},
},
};
export default schedule;
Monthly triggers
Field | Description | Required? |
---|---|---|
type | How often the trigger will activate: monthly | Required |
on_days | The day of the week the trigger should activate on. Provide the on_week_num value along with this field. | Required |
repeats_every | How often the trigger will repeat, respective to frequency.type | Required |
on_week_num | The nth week of the month the trigger will repeat | Optional |
Example monthly trigger
import { TriggerTypes } from "deno-slack-api/mod.ts";
import { ScheduledTrigger } from "deno-slack-api/typed-method-types/workflows/triggers/scheduled.ts";
import { ExampleWorkflow } from "../workflows/example_workflow.ts";
const schedule: ScheduledTrigger<typeof ExampleWorkflow.definition> = {
name: "Sample",
type: TriggerTypes.Scheduled,
workflow: `#/workflows/${ExampleWorkflow.definition.callback_id}`,
inputs: {},
schedule: {
// Starts 60 seconds after creation
start_time: new Date(new Date().getTime() + 60000).toISOString(),
frequency: {
type: "monthly",
repeats_every: 3,
on_days: ["Friday"],
on_week_num: 1,
},
},
};
export default schedule;
Yearly triggers
Field | Description | Required? |
---|---|---|
type | How often the trigger will activate: yearly | Required |
repeats_every | How often the trigger will repeat, respective to frequency.type | Required |
on_week_num | The nth week of the month the trigger will repeat | Optional |
Example yearly trigger
import { TriggerTypes } from "deno-slack-api/mod.ts";
import { ScheduledTrigger } from "deno-slack-api/typed-method-types/workflows/triggers/scheduled.ts";
import { ExampleWorkflow } from "../workflows/example_workflow.ts";
const schedule: ScheduledTrigger<typeof ExampleWorkflow.definition> = {
name: "Sample",
type: TriggerTypes.Scheduled,
workflow: `#/workflows/${ExampleWorkflow.definition.callback_id}`,
inputs: {},
schedule: {
// Starts 60 seconds after creation
start_time: new Date(new Date().getTime() + 60000).toISOString(),
frequency: {
type: "yearly",
repeats_every: 2,
},
},
};
export default schedule;
Scheduled trigger response
The response will have a property called ok
. If true
, then the trigger was created, and the trigger
property will be populated.
Your response will include a trigger.id
; be sure to store it! You use that to update
or delete
the trigger if need be. See trigger management.
Onward
➡️ With your trigger created, you can now test your app by running your app locally.
✨ Once your app is active, see trigger management for info on managing your triggers in your workspace.