/contact.ashx · public API

POST /contact.ashx #

Submit a contact form. The handler validates the inputs, verifies the captcha first, applies an IP-based rate limit, and drops an RFC 822 .eml file into the IIS SMTP pickup directory for delivery via the configured smart host.

Request

Form fields (application/x-www-form-urlencoded or multipart/form-data):

• name — 1–120 chars
• email — valid RFC 5321-shape
• subject — 0–200 chars
• message — 1–6000 chars
• captcha_token — signed token from /captcha.ashx
• captcha_answer — the integer the user typed in

Response

application/json: { "ok": true } on success.

Errors (verified 2026-06-05)

• 400 invalid_request — missing field, too long, invalid email shape.

  {"error":"invalid_request","error_description":"name + email + message required"}

• 400 captcha_failed — token or answer don’t match.

  {"error":"captcha_failed","error_description":"…"}

• 405 — non-POST request.
• 429 — 5 messages per IP per hour.
• 500 — pickup directory misconfigured or unwritable.

Example (complete flow)

# 1) Fetch a fresh captcha
$ CAP=$(curl -s https://phone.codeb.io/captcha.ashx)
$ echo "$CAP"
{"question":"5 + 8","token":"MTMuMTc4MDMwMTY1Nw.ocgav3cb_..."}

# 2) Show the question to your user, capture the answer (here: 13)
$ TOK=$(echo "$CAP" | python3 -c "import sys,json; print(json.load(sys.stdin)['token'])")

# 3) Submit the contact message
$ curl -X POST https://phone.codeb.io/contact.ashx \
    --data-urlencode "name=Alex Example" \
    --data-urlencode "email=alex@example.com" \
    --data-urlencode "subject=API test" \
    --data-urlencode "message=Hello, this is a test." \
    --data-urlencode "captcha_token=$TOK" \
    --data-urlencode "captcha_answer=13"
{"ok":true}