Add percentageThreshold parameter

README.md

@@ -57,6 +57,22 @@ specify what branch to compare with.
     compareBranch: 'your-branch-name'
 ```
 
+### Setting a percentage threshold
+
+To avoid comment spam, you can set a minimum percentage change required before a
+comment is posted.
+
+```yml
+- name: Time reporter
+  uses: DeviesDevelopment/workflow-timer@v0.2.0
+  with:
+    percentageThreshold: 10
+```
+
+With `percentageThreshold: 10`, comments will only be posted when the workflow
+duration changes by 10% or more. If a previous comment exists and the threshold
+is no longer met, the comment will be automatically deleted.
+
 ## How to contribute
 
 Feel free to open a pull request! All contributions, no matter how small, are

__tests__/main.test.ts

@@ -6,6 +6,7 @@ const listWorkflowRuns = jest.fn()
 const listComments = jest.fn()
 const createComment = jest.fn()
 const updateComment = jest.fn()
+const deleteComment = jest.fn()
 
 jest.unstable_mockModule('../src/githubClient.js', () => ({
   default: class {
@@ -14,6 +15,7 @@ jest.unstable_mockModule('../src/githubClient.js', () => ({
     listComments = listComments
     createComment = createComment
     updateComment = updateComment
+    deleteComment = deleteComment
   }
 }))
 
@@ -78,7 +80,8 @@ describe('main', () => {
     await run(
       { ...DEFAULT_CONTEXT, eventName: 'not-pull_request' },
       'fake-token',
-      'main'
+      'main',
+      0
     )
     expect(createComment).not.toHaveBeenCalled()
     expect(updateComment).not.toHaveBeenCalled()
@@ -92,7 +95,8 @@ describe('main', () => {
         workflow: 'My workflow'
       },
       'fake-token',
-      'main'
+      'main',
+      0
     )
 
     expect(createComment).toHaveBeenCalledWith(
@@ -122,7 +126,8 @@ describe('main', () => {
         workflow: 'Another workflow'
       },
       'fake-token',
-      'main'
+      'main',
+      0
     )
 
     expect(updateComment).toHaveBeenCalledWith(
@@ -159,11 +164,97 @@ describe('main', () => {
         workflow: 'Some workflow'
       },
       'fake-token',
-      'main'
+      'main',
+      0
     )
 
     expect(createComment).toHaveBeenCalledWith(
       '🕒 Workflow "Some workflow" took 180s which is an increase with 120s (200.00%) compared to latest run on main.'
     )
   })
+
+  it('does not create comment when change is below threshold', async () => {
+    getCurrentWorkflowRun.mockReturnValueOnce({
+      data: {
+        run_started_at: '2025-04-29T13:57:00Z',
+        workflow_id: 42
+      }
+    })
+    listWorkflowRuns.mockReturnValueOnce({
+      data: {
+        workflow_runs: [
+          {
+            ...DEFAULT_WORKFLOW_RUN,
+            run_started_at: '2025-04-28T13:56:30Z',
+            updated_at: '2025-04-28T13:59:40Z',
+            head_branch: 'main',
+            status: 'completed',
+            conclusion: 'success'
+          }
+        ]
+      }
+    })
+    await run(
+      {
+        ...DEFAULT_CONTEXT,
+        eventName: 'pull_request',
+        workflow: 'Some workflow'
+      },
+      'fake-token',
+      'main',
+      10
+    )
+
+    expect(createComment).not.toHaveBeenCalled()
+    expect(updateComment).not.toHaveBeenCalled()
+  })
+
+  it('deletes existing comment when change is below threshold', async () => {
+    getCurrentWorkflowRun.mockReturnValueOnce({
+      data: {
+        run_started_at: '2025-04-29T13:57:00Z',
+        workflow_id: 42
+      }
+    })
+    listWorkflowRuns.mockReturnValueOnce({
+      data: {
+        workflow_runs: [
+          {
+            ...DEFAULT_WORKFLOW_RUN,
+            run_started_at: '2025-04-28T13:56:30Z',
+            updated_at: '2025-04-28T13:59:40Z',
+            head_branch: 'main',
+            status: 'completed',
+            conclusion: 'success'
+          }
+        ]
+      }
+    })
+    listComments.mockReturnValueOnce({
+      data: [
+        {
+          id: 123,
+          user: {
+            login: 'github-actions[bot]',
+            type: 'Bot'
+          },
+          body: '🕒 Workflow "Some workflow" took...'
+        }
+      ]
+    })
+    await run(
+      {
+        ...DEFAULT_CONTEXT,
+        eventName: 'pull_request',
+        workflow: 'Some workflow'
+      },
+      'fake-token',
+      'main',
+      10
+    )
+
+    expect(deleteComment).toHaveBeenCalledWith(123)
+    expect(createComment).not.toHaveBeenCalled()
+    expect(updateComment).not.toHaveBeenCalled()
+  })
 })

action.yml

@@ -15,6 +15,12 @@ inputs:
       branch).'
     required: false
     default: 'main'
+  percentageThreshold:
+    description:
+      'Minimum percentage change required to post a comment. Must be a
+      non-negative number. Set to 0 to always post comments.'
+    required: false
+    default: '0'
 runs:
   using: 'node24'
   main: 'dist/index.js'

src/githubClient.ts

@@ -53,4 +53,12 @@ export default class GitHubClient {
       body
     })
   }
+
+  async deleteComment(commentId: number) {
+    return this.github.rest.issues.deleteComment({
+      owner: this.ctx.repo.owner,
+      repo: this.ctx.repo.repo,
+      comment_id: commentId
+    })
+  }
 }

src/index.ts

@@ -5,7 +5,13 @@ import { run } from './main.js'
 try {
   const token = core.getInput('token')
   const compareBranch = core.getInput('compareBranch')
-  run(context, token, compareBranch)
+  const percentageThreshold = parseFloat(core.getInput('percentageThreshold'))
+
+  if (isNaN(percentageThreshold) || percentageThreshold < 0) {
+    throw new Error('percentageThreshold must be a non-negative number')
+  }
+
+  run(context, token, compareBranch, percentageThreshold)
 } catch (error) {
   if (error instanceof Error) {
     core.setFailed(error.message)

src/main.ts

@@ -6,7 +6,8 @@ import { GhActionsContext } from './types.js'
 export async function run(
   context: GhActionsContext,
   token: string,
-  compareBranch: string
+  compareBranch: string,
+  percentageThreshold: number = 0
 ): Promise<void> {
   const ghClient = new GitHubClient(token, context)
   if (context.eventName != 'pull_request') {
@@ -25,17 +26,31 @@ export async function run(
     currentRun.data,
     latestRunOnCompareBranch
   )
-  const outputMessage = generateComment(
-    context.workflow,
-    compareBranch,
-    durationReport
-  )
+
+  const meetsThreshold =
+    !durationReport ||
+    Math.abs(durationReport.diffInPercentage) >= percentageThreshold
 
   const existingComments = await ghClient.listComments()
   const existingComment = existingComments.data
     .reverse()
     .find(previousCommentFor(context.workflow))
 
+  if (!meetsThreshold && existingComment) {
+    await ghClient.deleteComment(existingComment.id)
+    return
+  }
+
+  if (!meetsThreshold) {
+    return
+  }
+
+  const outputMessage = generateComment(
+    context.workflow,
+    compareBranch,
+    durationReport
+  )
+
   if (existingComment) {
     await ghClient.updateComment(existingComment.id, outputMessage)
   } else {