formulosity

Formulosity is a self-hosted app for building and deploying the surveys using code instead of traditional survey builders.

This approach offers a number of advantages, including:

• Version control: Survey files can be stored in a Github repository, which makes it easy to track changes and collaborate with others.
• Reproducibility: Survey files can be easily shared and reproduced, making it easy to reuse surveys or create variations of existing surveys.
• Automation: Survey files can be used to automate the creation and deployment of surveys, which can save time and effort.

Formulosity uses human-readable declarative language YAML.

Features

• Management API
• Survey UI: for end users (respondents)
• Console UI: manage surveys
• YAML survey configuration
• Basic question types
• Default theme
• Custom themes support
• Personalized options: intro, outro, etc.
• Cookie/IP deduplication
• Admin user authentication
• Advanced validation rules
• Detect survey changes in real time

See it in Action! Demo Links

Console UI - simple - custom_theme - short - many_options

Note: use user / pass to login into the Console UI.

Survey Structure

Each directory in SURVEYS_DIR is a survey. You can configure the source of your surveys by setting different SURVEYS_DIR env var.

surveys/
├── survey1/
│   ├── metadata.yaml
│   ├── questions.yaml
│   ├── security.yaml
│   ├── variables.yaml
│   └── ...
└── survey2/
    ├── metadata.yaml
    ├── questions.yaml
    └── ...

To get started, check out the ./surveys folder with multiple examples.

Survey Files

metadata.yaml

This file is required! The file consists of a YAML object with specific properties describing the survey.

• title: This is the main title displayed to users at the beginning of the survey.
• theme: This specifies the visual theme applied to the survey. Currently supported themes are: default.
• intro: This text appears as an introduction before the first question.
• outro: This text appears as a conclusion after the last question.

title: Survey Title
theme: default # or custom
intro: |
  This is the introduction to the survey.
  It can be multiple lines long.
outro: |
  Thank you for taking the survey.
  Your feedback is important to us.

questions.yaml

This file is required! The file consists of a list of questions, each defined as a YAML object with specific properties.

• type: This specifies the type of question being asked.
• id: This provides a unique identifier for the question. It is useful for referencing specific questions in branching logic or data analysis. IDs must be unique across all questions in the survey.
• label: This is the text displayed to the user as the question itself.
• description: This provides additional information about the question for the user, such as clarification or instructions.
• options: This list defines the available answer choices for question types like single-choice, multiple-choice and ranking.
• optionsFromVariable: This property references a variable defined in a separate variables.yaml file. The variable should contain a list of options to be used for the question. This allows for reusability and centralized management of option lists.
• validation: This property is used to define validation rules for specific question types.

questions:
  - type: single-choice
    id: question1 # optional ID, must be unique across all questions
    label: What is the capital of Germany?
    description: You can select multiple options
    optionsFromVariable: german-city-options # defined in variables.yaml
    options:
      - Berlin
      - Munich
      - Paris
      - London
      - Hamburg
      - Cologne
    validation:
      min: 1
      max: 3

security.yaml

This file is optional. The file consists of a YAML object with specific properties for survey security settings.

• duplicateProtection: This property defines how the platform handles duplicate responses from the same user.

duplicateProtection: cookie # cookie | ip

variables.yaml

This file is optional. The file consists of a list of variables, each defined as a YAML object with specific properties.

• id: This unique identifier references the variable within questions. IDs must be unique across all variables defined in the file.
• type: This specifies the type of data stored in the variable. Currently supported types are: list.

variables:
  - id: german-city-options # must be unique
    type: list
    options:
      - Berlin
      - Munich
      - Hamburg
      - Cologne

Question Types

Short Text

Prompts users for a brief written answer.

- type: short-text
  label: What is the capital of Germany?

Long Text

Prompts users for a detailed written answer.

- type: long-text
  label: What is the capital of Germany?

Single Choice

Presents a question with only one correct answer from a list of options.

- type: single-choice
  label: What is the capital of Germany?
  options:
    - Berlin
    - Munich
    - Paris
    - London
    - Hamburg
    - Cologne

Multiple Choice

Presents a question where users can select multiple answers (with limitations). You can customize the minimum and maximum allowed selections in the validation section.

- type: multiple-choice
  label: Which of the following are cities in Germany?
  description: You can select multiple options
  validation:
    min: 1
    max: 3
  options:
    - Berlin
    - Munich
    - Paris
    - London
    - Hamburg
    - Cologne

Date

Asks users to enter a specific date.

- type: date
  label: When was the Berlin Wall built?

Rating

Presents a scale for users to rate something on a predefined range.

- type: rating
  label: How much do you like Berlin?
  min: 1
  max: 5

Ranking

Asks users to rank options based on a given criteria.

- type: ranking
  label: Rank the following cities by population
  optionsFromVariable: german-city-options

Yes/No

Presents a question where users can only answer "yes" or "no".

- type: yes-no
  label: Is Berlin the capital of Germany?

Screenshots

Installation: Docker

docker-compose up -d --build

And you should be able to access the UI on http://localhost:3000 (default basic auth: user:pass).

Deployment

There are 3 parts that need to be deployed:

• Go backend. It's packaged as a Docker container and can be deployed to any cloud provider.
• Postgres database. You can use managed Postgres services or deploy it yourself.
• Next.js frontend. It's also packaged as a Docker container, but also can be deployed to Vercel or Netlify.

The demo service (links above) is deployed to Fly.io (Go, Postgres) and Vercel (Next.js) and are under the free tiers.

Environment Variables

Go backend:

• DATABASE_URL - Postgres connection string
• LOG_LEVEL - Log level, e.g. info
• SURVEYS_DIR - Directory with surveys, e.g. /root/surveys

UI:

• CONSOLE_API_ADDR - Internal address of the Go backend, e.g. http://api:8080 (could be the same as NEXT_PUBLIC_CONSOLE_API_ADDR)
• NEXT_PUBLIC_CONSOLE_API_ADDR - Public address of the Go backend. Needs to be set as a build arg for the Docker image, since it's needed for npm run build.
• IRON_SESSION_SECRET - Secret for session encryption
• HTTP_BASIC_AUTH - Format: user:pass for basic auth (optional)

Tech Stack

• Backend: Go, Postgres
• UI: Next.js, Tailwind CSS

Create new Postgres migration

Make sure to install go-migrate first.

migrate create -dir migrations/postgres -ext sql -seq name

Run Go tests

make test

Contributing Guidelines

Pull requests, bug reports, and all other forms of contribution are welcomed and highly encouraged!