Manual trigger workflow for CircleCI

.circleci-config.yml

version: 2.1

parameters:
  my_trigger_parameter:
    type: string
    default: ""

workflows:
  # Workflow triggered by API call / hitting "Trigger Pipeline" in the web interface
  api-triggered-workflow:
    when: << pipeline.parameters.my_trigger_parameter >>
    jobs:
    - do-the-thing:
        my_job_param: << pipeline.parameters.my_trigger_parameter >>
  # Workflow triggered only by pushing a commit to the repository
  commit-triggered-workflow:
    when:
      not: << pipeline.parameters.my_trigger_parameter >>
    jobs:
    - do-the-thing

jobs:
  do-the-thing:
    parameters:
      my_job_param:
        type: string
        default: "triggered by commit"
    steps:
      - run: echo << parameters.my_job_param >>

manual_trigger.sh

curl --location --request POST 'https://circleci.com/api/v2/project/<org slug>/<project slug>/pipeline' \
--header 'Circle-Token: <YOUR CIRCLECI API TOKEN>' \
--header 'Content-Type: application/json' \
--data-raw '{
    "branch": "my-branch-name",
    "parameters": {
        "my_trigger_parameter": "triggered by API"
    }
}'