Ruby

Call Formerie from any Ruby server with net/http, from the standard library, with no gem to install. You don’t need a Formerie package or an API key: a form’s public address is all it takes.

Submit a form

Save this as submit.rb, and run ruby submit.rb.

Ruby

require "json"
require "net/http"

runtime_url = ENV.fetch("FORMERIE_RUNTIME_URL", "https://forms.formerie.com")
# Your form. This is the only line that names it.
form = ENV.fetch("FORMERIE_FORM", "acme/contact")

uri = URI("#{runtime_url}/#{form}/submit")
response = Net::HTTP.start(uri.host, uri.port, use_ssl: uri.scheme == "https", open_timeout: 5, read_timeout: 10) do |http|
  http.post(uri.path, JSON.generate(fields: {
    name: "Jane Example",
    email: "jane@example.com",
    message: "Hello from my server"
  }), "Content-Type" => "application/json")
end
result = JSON.parse(response.body)
puts "#{response.code} #{result["ok"] ? result["submissionUid"] : result.dig("error", "code")}"

Replace acme/contact, on the marked line, with your own handles. A success is HTTP 202, with a submissionUid such as sub_p6dr8wq2j7tkan: the answers are stored, and their email is queued. Each sample reads two optional settings from the environment, FORMERIE_RUNTIME_URL for a hostname you’ve connected, and FORMERIE_FORM for the handles.

Before you start

Publish a form, and take its workspace and form handles from the Publish tab. Your server doesn’t need to be in the form’s allowed websites.
To try things without emailing anyone, create a test key on the form’s Tests tab, and put it in an environment variable called FORMERIE_TEST_KEY:

Ruby

require "json"
require "net/http"

runtime_url = ENV.fetch("FORMERIE_RUNTIME_URL", "https://forms.formerie.com")
# Your form. This is the only line that names it.
form = ENV.fetch("FORMERIE_FORM", "acme/contact")

uri = URI("#{runtime_url}/#{form}/submit")
response = Net::HTTP.start(uri.host, uri.port, use_ssl: uri.scheme == "https", open_timeout: 5, read_timeout: 10) do |http|
  http.post(uri.path, JSON.generate(fields: {
    name: "Jane Example",
    email: "jane@example.com",
    message: "Just a test"
  }), {
    "Content-Type" => "application/json",
    # Keep the key out of your code. A test is stored apart and emails nobody.
    "X-Formerie-Test-Key" => ENV.fetch("FORMERIE_TEST_KEY")
  })
end
result = JSON.parse(response.body)
puts "#{response.code} #{result["ok"] ? result["submissionUid"] : result.dig("error", "code")}"

A test comes back as tst_..., is stored apart, and emails nobody. A wrong key gets TEST_KEY_INVALID, HTTP 401, and nothing is stored. Remove the header before you go live, since a key left in place files everything as a test. See Test from a server or CI.

Check answers without submitting

validate checks answers and stores nothing, so you can flag a problem early. It answers 200 when they pass, and 422 with the same errors as a submission when they don’t. The final submission always checks the whole form again.

Ruby

require "json"
require "net/http"

def post_json(action, payload)
  runtime_url = ENV.fetch("FORMERIE_RUNTIME_URL", "https://forms.formerie.com")
  # Your form. This is the only line that names it.
  form = ENV.fetch("FORMERIE_FORM", "acme/contact")
  uri = URI("#{runtime_url}/#{form}/#{action}")
  Net::HTTP.start(uri.host, uri.port, use_ssl: uri.scheme == "https", open_timeout: 5, read_timeout: 10) do |http|
    http.post(uri.path, JSON.generate(payload), "Content-Type" => "application/json")
  end
end

# Checks answers and stores nothing. With no step, only the fields you send are checked.
def check_answers(fields, step: nil)
  payload = step ? { mode: "step", step: step, fields: fields } : { mode: "partial", fields: fields }
  result = JSON.parse(post_json("validate", payload).body)
  return result if result["ok"] || result.dig("error", "code") == "VALIDATION_FAILED"

  raise result.dig("error", "code")
end

By default, only the fields you send are checked. Pass a step to check every field in that step instead, on a form with steps. A step the form doesn’t have gets BAD_REQUEST.

Show errors per field

Answers that fail come back as VALIDATION_FAILED, HTTP 422, and nothing is stored. error.fields holds the problems by field, and error.issues holds the same ones in order. Each has a path, a code to match on, and a message that’s safe to show, in the form’s language.

Ruby

require "erb"
require "json"
require "net/http"

def submit_answers(fields)
  runtime_url = ENV.fetch("FORMERIE_RUNTIME_URL", "https://forms.formerie.com")
  # Your form. This is the only line that names it.
  form = ENV.fetch("FORMERIE_FORM", "acme/contact")
  uri = URI("#{runtime_url}/#{form}/submit")
  response = Net::HTTP.start(uri.host, uri.port, use_ssl: uri.scheme == "https", open_timeout: 5, read_timeout: 10) do |http|
    http.post(uri.path, JSON.generate(fields: fields), "Content-Type" => "application/json")
  end
  JSON.parse(response.body)
end

# Finds the visitor's answer for a path such as contact.email, so the form can show it again.
def answer_at(answers, path)
  path.split(".").reduce(answers) { |value, part| value.is_a?(Hash) ? value[part] : nil }.to_s
end

# One input with its answer kept and its first message under it.
def render_field(path, answers, result)
  message = result.dig("error", "fields", path, 0, "message")
  error = message ? %(<p class="error">#{ERB::Util.html_escape(message)}</p>) : ""
  %(<input name="#{ERB::Util.html_escape(path)}" value="#{ERB::Util.html_escape(answer_at(answers, path))}">#{error})
end

A field inside a group has a path such as contact.email, and one inside a list has guests[0].email, so split the path to find its answer. See Field paths. Show the visitor’s answers again with the messages, escaped, so they only have to fix what’s wrong.

Retry safely

A network failure doesn’t tell you whether the submission arrived. So send one metadata.idempotencyKey per submission, the same on every retry. Formerie then counts and delivers it once, and answers a repeat with DUPLICATE_SUBMISSION, HTTP 409, which means the first one worked.

Ruby

require "json"
require "net/http"
require "securerandom"

MAX_ATTEMPTS = 3
LONGEST_WAIT = 30
TEMPORARY_CODES = %w[FORM_MAINTENANCE QUEUE_FAILED INTERNAL_ERROR].freeze

# One attempt. Says what happened, and whether another attempt could help.
def send_once(fields, key)
  runtime_url = ENV.fetch("FORMERIE_RUNTIME_URL", "https://forms.formerie.com")
  # Your form. This is the only line that names it.
  form = ENV.fetch("FORMERIE_FORM", "acme/contact")
  uri = URI("#{runtime_url}/#{form}/submit")
  body = JSON.generate(fields: fields, metadata: { idempotencyKey: key })

  begin
    response = Net::HTTP.start(uri.host, uri.port, use_ssl: uri.scheme == "https", open_timeout: 5, read_timeout: 10) do |http|
      # net/http retries some requests by itself, and this loop does that with a wait.
      http.max_retries = 0
      http.post(uri.path, body, "Content-Type" => "application/json")
    end
  rescue SystemCallError, SocketError, IOError, Timeout::Error, OpenSSL::SSL::SSLError
    return { outcome: "retry-later", reason: "network", again: true }
  end
  status = response.code.to_i

  # Only the short-term limit sends Retry-After. A form's own limit can last an hour, so don't wait for it.
  if status == 429
    after = response["Retry-After"]&.match?(/\A\d+\z/) ? response["Retry-After"].to_i : nil
    return { outcome: "retry-later", reason: "rate-limited", after: after, again: !after.nil? && after <= LONGEST_WAIT }
  end

  # Something in front of Formerie may answer without JSON, so look at the status first.
  begin
    result = JSON.parse(response.body)
  rescue JSON::ParserError
    return { outcome: "retry-later", reason: "bad-response", again: [502, 503, 504].include?(status) }
  end

  return { outcome: "accepted", id: result["submissionUid"] } if result["ok"]

  error = result["error"]
  case error["code"]
  when "DUPLICATE_SUBMISSION"
    # The first send worked, and only its answer was lost.
    { outcome: "accepted", duplicate: true }
  when *TEMPORARY_CODES
    { outcome: "retry-later", reason: error["code"], again: true }
  when "VALIDATION_FAILED"
    { outcome: "invalid", code: error["code"], issues: error["issues"] }
  else
    { outcome: "rejected", code: error["code"], message: error["message"] }
  end
end

# One key per submission, the same on every retry. Store it with the answers if you retry later.
def submit_with_retries(fields, key = SecureRandom.uuid)
  (1..MAX_ATTEMPTS).each do |attempt|
    answer = send_once(fields, key)
    again = answer.delete(:again)
    return answer.merge(key: key, attempts: attempt) if !again || attempt == MAX_ATTEMPTS

    backoff = rand * [0.25 * (2**attempt), 4].min
    sleep [answer[:after] || 0, backoff].max
  end
end

Answer	Retry?
No connection, or a timeout	Yes, with the same key
`429` with `Retry-After`	Yes, after that wait, if it’s short. The short-term limit answers with `Retry-After: 60`
`429` with no `Retry-After`	No. A form’s own limit can last an hour, so ask the visitor to try again later
`FORM_MAINTENANCE`, `QUEUE_FAILED`, `INTERNAL_ERROR`	Yes, after a short wait
`502`, `503` or `504` with no JSON	Yes. Something in front of Formerie answered
Any other answer with no JSON	No. Keep the key, and look into it
`DUPLICATE_SUBMISSION`	No. Treat it as a success
`VALIDATION_FAILED` and any other code	No. The answer won’t change

The key must be a non-empty string. Anything else is ignored, and there’s no repeat check.
A repeat is noticed for 300 seconds by default, under the form’s repeat window. See What the repeat window covers.
The check comes first, so a key that went through gets DUPLICATE_SUBMISSION even with different answers. Use a new key for each new submission. A key refused for its answers was never accepted, so it can go again once they’re fixed.
A retry after QUEUE_FAILED can store a second copy, which you’d see under Submissions. It’s rare.

Human verification

If your form requires human verification, use your own keys, with your site in the provider’s list of domains and in the form’s allowed websites. The widget adds its token to your form. Forward two things:

The token, as verificationToken, taken out of the fields.
The Origin of the visitor’s request, because Formerie compares the token’s domain with it. A server sends none by itself, and the check then fails with TURNSTILE_FAILED.

Ruby

require "json"
require "net/http"

# posted is what your form sent. origin is the Origin header of the visitor's request.
def submit_verified(posted, origin)
  runtime_url = ENV.fetch("FORMERIE_RUNTIME_URL", "https://forms.formerie.com")
  # Your form. This is the only line that names it.
  form = ENV.fetch("FORMERIE_FORM", "acme/contact")
  uri = URI("#{runtime_url}/#{form}/submit")

  fields = posted.dup
  token = fields.delete("cf-turnstile-response")
  headers = { "Content-Type" => "application/json" }
  # Without the visitor's Origin, the provider's hostname can't match, and the check fails.
  headers["Origin"] = origin unless origin.to_s.empty?

  response = Net::HTTP.start(uri.host, uri.port, use_ssl: uri.scheme == "https", open_timeout: 5, read_timeout: 10) do |http|
    http.post(uri.path, JSON.generate(fields: fields, verificationToken: token), headers)
  end
  JSON.parse(response.body)
end

An Origin that isn’t in the form’s allowed websites gets FORBIDDEN_ORIGIN. Only forward it for this: on any other form, it turns on a check your server doesn’t otherwise need. The widget needs JavaScript in the visitor’s browser. See Verification on the server path.

Spam checks

Hosted pages and embeds send this metadata for you. From your server, send it yourself, or those checks are skipped.

Ruby

require "json"
require "net/http"
require "securerandom"
require "time"

def submit_with_metadata(fields, started_at, visitor_id)
  runtime_url = ENV.fetch("FORMERIE_RUNTIME_URL", "https://forms.formerie.com")
  # Your form. This is the only line that names it.
  form = ENV.fetch("FORMERIE_FORM", "acme/contact")
  uri = URI("#{runtime_url}/#{form}/submit")
  payload = {
    fields: fields,
    metadata: {
      idempotencyKey: SecureRandom.uuid,
      # When the visitor opened the form, for the minimum submit time check.
      startedAt: started_at.utc.iso8601,
      pageUrl: "https://www.example.com/contact",
      # Your own visitor ID, for a limit rule with the deviceToken scope.
      deviceToken: visitor_id
    }
  }
  response = Net::HTTP.start(uri.host, uri.port, use_ssl: uri.scheme == "https", open_timeout: 5, read_timeout: 10) do |http|
    http.post(uri.path, JSON.generate(payload), "Content-Type" => "application/json")
  end
  JSON.parse(response.body)
end

Field	What it’s for
`idempotencyKey`	The repeat check, as above
`startedAt`	When the visitor opened the form, as an ISO 8601 time. Sent sooner than the form’s minimum, 1 second by default, it gets `SPAM_REJECTED`. Keep the real time from when you showed the form, not the time of this call. One that can’t be read skips the check
`pageUrl`	The page the form was sent from. Stored only if it’s an http or https address
`deviceToken`	Your own visitor ID, for a limit per visitor, below

The hidden field check runs when your form sends that field, and links and human verification run on the server either way. See Spam and limits.

Limits from your server

Formerie counts visitors by network address, and from here, that’s your server’s. Every visitor counts as your server.

Limit	Default	From your server
Per visitor	30 submissions every 10 minutes	Shared by all your visitors. Raise it before you launch, or leave it empty for no limit, under Settings, then Submission limits
Whole form	1,000 submissions an hour	The same. On the Free plan, it’s also the most a form can accept
Short-term	120 requests a minute for each form from one address	Can’t be changed. It’s the only one that sends `Retry-After`. `validate` counts here too

Over any of them, you get RATE_LIMITED, HTTP 429. To keep a limit for each visitor, a rule with the deviceToken scope counts by the ID you send, such as a hash of the visitor’s address. The app’s settings don’t offer that rule yet, so talk to us to set one up, and keep the whole-form limit, since anyone calling the form directly can change their ID. See Limits on the server path for the reasoning, and Plans and limits for monthly counts.

Rails

This works through the API: the controller reads the visitor’s form, and calls Formerie with net/http. It was run against a local Formerie backend with Rails 8.1. It answers 202 with the submission’s ID, the same status as Formerie with messages by field, or 503 when it can’t reach Formerie. Route it with post "/contact", to: "contact#create", and keep Rails’ forgery protection on, with form_with in your view.

Ruby

require "json"
require "net/http"

class ContactController < ActionController::Base
  def create
    runtime_url = ENV.fetch("FORMERIE_RUNTIME_URL", "https://forms.formerie.com")
    # Your form. This is the only line that names it.
    form = ENV.fetch("FORMERIE_FORM", "acme/contact")
    uri = URI("#{runtime_url}/#{form}/submit")
    # Name the fields you send, so a visitor can't add others.
    fields = params.permit(:name, :email, :message).to_h
    answer = Net::HTTP.start(uri.host, uri.port, use_ssl: uri.scheme == "https", open_timeout: 5, read_timeout: 10) do |http|
      http.max_retries = 0
      http.post(uri.path, JSON.generate(fields: fields), "Content-Type" => "application/json")
    end
    result = JSON.parse(answer.body)

    if result["ok"]
      render json: { id: result["submissionUid"] }, status: :accepted
    else
      errors = (result.dig("error", "fields") || {}).transform_values { |issues| issues.map { |issue| issue["message"] } }
      render json: { code: result.dig("error", "code"), errors: errors }, status: answer.code.to_i
    end
  rescue SystemCallError, SocketError, IOError, Timeout::Error, OpenSSL::SSL::SSLError, JSON::ParserError
    # No connection, a timeout, or an answer that isn't JSON. Keep the visitor's answers on screen.
    render json: { code: "TRY_AGAIN" }, status: :service_unavailable
  end
end

Good to know

read_timeout defaults to 60 seconds, which is long for a page someone’s waiting on. Keep open_timeout and read_timeout on every call.
Keep test keys and answers out of your logs. A requestId in an error, or the X-Request-Id header, is what to log and to quote when you ask for help.
Match on error.code, never on the message, since a form can reword its messages and a status can cover several codes. Error codes lists them all.

With	Note
Rails’ `Origin`	`request.headers["Origin"]`, for human verification.
Sinatra	`params` holds the answers, and `request.env["HTTP_ORIGIN"]` the visitor’s `Origin`.

The routes, fields and every error are in the API reference.