Better questions using a python script

3 files changed, 241 insertions, 114 deletions

diff --git a/regional-currency/ask_questions.py b/regional-currency/ask_questions.py
new file mode 100755
index 0000000..8c36311
--- /dev/null
+++ b/regional-currency/ask_questions.py
@@ -0,0 +1,238 @@
+#!/usr/bin/env python3
+
+import base64
+import os
+import subprocess
+import uuid
+from typing import Callable, Dict, TypeVar
+
+log = open("setup.log", "ab", buffering=0)
+CONFIG_FILE = "config/user.conf"
+
+
+def load_conf() -> Dict[str, str]:
+    conf = {}
+    with open(CONFIG_FILE, "r") as f:
+        for kv in f.read().splitlines():
+            if len(kv) != 0:
+                [k, v] = [part.strip() for part in kv.split("=", 1)]
+                conf[k] = v.strip('"').replace('\\"', '"')
+    return conf
+
+
+conf = load_conf()
+
+
+def add_conf(name: str, value: str):
+    conf[name] = value
+    content = ""
+    for key, value in conf.items():
+        escaped = value.replace('"', '\\"')
+        content += f'{key}="{escaped}"\n'
+    with open(CONFIG_FILE, "w") as f:
+        f.write(content)
+
+
+def run_cmd(
+    cmd: list[str], input: str | None = None, env: Dict[str, str] | None = None
+) -> int:
+    result = subprocess.run(
+        cmd,
+        stdout=subprocess.PIPE,
+        stderr=subprocess.STDOUT,
+        input=input.encode() if input is not None else None,
+        stdin=subprocess.DEVNULL if input is None else None,
+        env=env,
+    )
+    log.write(result.stdout)
+    if result.returncode != 0:
+        print(result.stdout.decode("utf-8"), end="")
+    return result.returncode
+
+
+def try_cmd(
+    cmd: list[str], input: str | None = None, env: Dict[str, str] | None = None
+) -> bool:
+    return run_cmd(cmd, input, env) == 0
+
+
+A = TypeVar("A")
+T = TypeVar("T")
+
+
+def custom(
+    name: str | None,
+    action: Callable[[], str | None],
+    default: T | None = None,
+    check: Callable[[str], T | None] = lambda it: it,
+    fmt: Callable[[T], str] = lambda it: str(it),
+):
+    if name is not None:
+        prev = conf.get(name, None)
+        if prev is not None:  # If got previous value
+            checked = check(prev)
+            if checked is not None:  # And previous value is valid
+                add_conf(name, fmt(checked))  # Add again in case normalization changed
+                return checked
+
+    while True:
+        raw = action()
+        if raw is None:
+            if default is not None:
+                if name is not None:
+                    add_conf(name, fmt(default))
+                return default
+            continue
+        else:
+            checked = check(raw)
+            if checked is not None:
+                if name is not None:
+                    add_conf(name, fmt(checked))
+                return checked
+
+
+def ask(
+    name: str | None,
+    msg: str,
+    default: T | None = None,
+    check: Callable[[str], T | None] = lambda it: it,
+    fmt: Callable[[T], str] = lambda it: str(it),
+) -> T:
+    def do_ask():
+        log.write(msg.encode())
+        log.write("\n".encode())
+        raw = input(msg).strip()
+        if raw == "":
+            if default is None:
+                print("You must enter a value")
+            return None
+        return raw
+
+    return custom(name, do_ask, default, check, fmt)
+
+
+def ask_str(name: str | None, msg: str, default: str | None = None) -> str:
+    return ask(name, msg, default)
+
+
+def ask_currency(name: str, msg: str, default: str | None = None) -> str:
+    def check_currency(currency: str) -> str | None:
+        currency = currency.upper()
+        if not currency.isascii() or not currency.isalpha():
+            print("The currency name must be an ASCII alphabetic string")
+        elif len(currency) < 3 or 11 < len(currency):
+            print("The currency name had to be between 3 and 11 characters long")
+        else:
+            return currency
+        return None
+
+    return ask(name, msg, default, check_currency)
+
+
+def ask_host(name: str, msg: str, default: str | None = None) -> str:
+    def check_host(host: str) -> str | None:
+        success = True
+        for subdomain in ["backend", "bank", "exchange"]:
+            success = try_cmd(["ping", "-c", "1", f"{subdomain}.{host}"]) and success
+        if success:
+            return host
+        else:
+            return None
+
+    return ask(name, msg, default, check_host)
+
+
+def ask_yes_no(name: str | None, msg: str, default: bool | None = None) -> bool:
+    def check_yes_no(raw: str) -> bool | None:
+        raw = raw.lower()
+        if raw == "y" or raw == "yes":
+            return True
+        elif raw == "n" or raw == "no":
+            return False
+        else:
+            print("Expected 'y' or 'n'")
+            return None
+
+    return ask(name, msg, default, check_yes_no, lambda it: "y" if it else "n")
+
+
+ask_currency(
+    "CURRENCY",
+    "1. Enter the name of the regional currency (e.g. 'NETZBON'): ",
+    "NETZBON",
+)
+ask_currency(
+    "FIAT_CURRENCY", "2. Enter the name of the fiat currency (e.g. 'CHF'): ", "CHF"
+)
+ask_str(
+    "BANK_NAME",
+    "3. Enter the human-readable name of the bank (e.g. 'Taler Bank'): ",
+    "Taler Bank",
+)
+ask_host("DOMAIN_NAME", "4. Enter the domain name (e.g. 'example.com'): ")
+if ask_yes_no("ENABLE_TLS", "5. Setup TLS using Let's Encrypt? (Y/n): ", True):
+    ask_str("TLS_EMAIL", "5.1. Enter an email address for Let's Encrypt: ")
+
+    def ask_tos():
+        print(
+            "5.2. Please read the Terms of Service at https://letsencrypt.org/documents/LE-SA-v1.3-September-21-2022.pdf."
+        )
+        if not ask_yes_no(
+            None,
+            "5.2. You must agree in order to register with the ACME server. Do you agree? (y/n): ",
+            False,
+        ):
+            print("You must agree in order to register with the ACME server")
+            return None
+        else:
+            return "y"
+
+    custom("TLS_TOS", ask_tos)
+    add_conf("PROTO", "https")
+else:
+    add_conf("PROTO", "http")
+
+if not ask_yes_no(
+    "DO_OFFLINE",
+    "6. Do you want Taler Exchange keys on this server (Y) or externally on another server (n): ",
+    True,
+):
+    ask_str("MASTER_PUBLIC_KEY", "6.1. Enter the exchange-offline master public key: ")
+
+if ask_yes_no(
+    "DO_TELESIGN",
+    "7. Setup sms two-factor authentication using Telesign https://www.telesign.com? (Y/n): ",
+    True,
+):
+
+    def ask_telesign():
+        customer_id = ask_str(None, "7.1. Enter your Telesign Customer ID: ")
+        api_key = ask_str(None, "7.2. Enter your Telesign API Key: ")
+        phone_number = ask_str(
+            None,
+            "7.3. Enter a phone number to test your API key (e.g. '+447911123456'): ",
+        )
+        auth_token = base64.b64encode(f"{customer_id}:{api_key}".encode()).decode()
+        if not try_cmd(
+            ["libeufin-tan-sms.sh", phone_number],
+            "12345",
+            {**os.environ, "AUTH_TOKEN": auth_token},
+        ):
+            print(
+                "Failed to send an sms using Telesign API, check your credentials and phone number"
+            )
+            return None
+        code = ask_str(None, f"7.4. Enter the code received by {phone_number} : ")
+        if code != "12345":
+            print(
+                f"Wrong code got '{code}' expected '12345', check your credentials and phone number"
+            )
+            return None
+        return auth_token
+
+    custom("TELESIGN_AUTH_TOKEN", ask_telesign)
+ask_str(
+    "BANK_ADMIN_PASSWORD",
+    "8. Enter the admin password for the bank (or press enter to autogenerate password): ",
+    str(uuid.uuid4()),
+)
diff --git a/regional-currency/functions.sh b/regional-currency/functions.sh
index 77616ba..749d1bd 100755
--- a/regional-currency/functions.sh
+++ b/regional-currency/functions.sh
@@ -22,106 +22,6 @@ function check_user() {
   fi
 }
 
-function ask_questions() {
-  if test -z "${CURRENCY:-}"; then
-    read -r -p "1. Enter the name of the regional currency (e.g. 'NETZBON'): " CURRENCY
-    CURRENCY=$(normalize_currency "${CURRENCY}")
-    echo "CURRENCY=${CURRENCY}" >>config/user.conf
-  fi
-  if test -z "${FIAT_CURRENCY:-}"; then
-    read -r -p "2. Enter the name of the fiat currency (e.g. 'CHF'): " FIAT_CURRENCY
-    FIAT_CURRENCY=$(normalize_currency "${FIAT_CURRENCY}")
-    echo "FIAT_CURRENCY=${FIAT_CURRENCY}" >>config/user.conf
-  fi
-  if test -z "${BANK_NAME:-}"; then
-    read -r -p "3. Enter the human-readable name of the bank (e.g. 'Taler Bank'): " BANK_NAME
-    echo "BANK_NAME=\"${BANK_NAME}\"" >>config/user.conf
-  fi
-  if test -z "${DOMAIN_NAME:-}"; then
-    read -r -p "4. Enter the domain name: " DOMAIN_NAME
-    # convert to lower-case
-    DOMAIN_NAME=$(echo "${DOMAIN_NAME}" | tr A-Z a-z)
-    check_dns
-    echo "DOMAIN_NAME=${DOMAIN_NAME}" >>config/user.conf
-  fi
-  if test -z "${ENABLE_TLS:-}"; then
-    read -r -p "5. Setup TLS using Let's Encrypt? (y/n): " ENABLE_TLS
-    echo "ENABLE_TLS=${ENABLE_TLS}" >>config/user.conf
-  fi
-  if test -z "${TLS_EMAIL:-}"; then
-    if test "${ENABLE_TLS:-}" == y; then
-      read -r -p "5.1. Enter an email address for Let's Encrypt: " TLS_EMAIL
-      echo "TLS_EMAIL=${TLS_EMAIL}" >>config/user.conf
-    fi
-  fi
-  if test -z "${TLS_TOS:-}"; then
-    if test "${ENABLE_TLS:-}" == y; then
-      echo "5.2. Please read the Terms of Service at https://letsencrypt.org/documents/LE-SA-v1.3-September-21-2022.pdf."
-      read -r -p "5.2. You must agree in order to register with the ACME server. Do you agree? (y/n): " TLS_TOS
-      if test "${TLS_TOS:-y}" != y; then
-        say "You must agree in order to register with the ACME server"
-        exit 1
-      fi
-      echo "TLS_TOS=${TLS_TOS}" >>config/user.conf
-    fi
-  fi
-  if test -z "${DO_OFFLINE:-}"; then
-    read -r -p "6. Do you want Taler Exchange keys on this server (y) or externally on another server (n): " DO_OFFLINE
-    echo "DO_OFFLINE=${DO_OFFLINE}" >>config/user.conf
-  fi
-  if test -z "${MASTER_PUBLIC_KEY:-}"; then
-    if test "${DO_OFFLINE:-y}" == n; then
-      read -r -p "6.1. Enter the exchange-offline master public key: " MASTER_PUBLIC_KEY
-      echo "MASTER_PUBLIC_KEY=${MASTER_PUBLIC_KEY}" >>config/user.conf
-    fi
-  fi
-  if test -z "${DO_TELESIGN:-}"; then
-    read -r -p "7. Setup sms two-factor authentication using Telesign https://www.telesign.com? (y/n): " DO_TELESIGN
-    if test "${DO_TELESIGN:-y}" != n; then
-      read -r -p "7.1. Enter your Telesign Customer ID: " TELESIGN_CUSTOMER_ID
-      read -r -s -p "7.2. Enter your Telesign API Key: " TELESIGN_API_KEY
-      echo "" # force new line
-      read -r -p "7.3. Enter a phone number to test your API key (e.g. '+447911123456'): " TELESIGN_PHONE
-      TELESIGN_AUTH_TOKEN=$(echo "$TELESIGN_CUSTOMER_ID:$TELESIGN_API_KEY" | base64 -w 0)
-      export AUTH_TOKEN=$TELESIGN_AUTH_TOKEN
-      echo "12345" | libeufin-tan-sms.sh $TELESIGN_PHONE
-      read -r -p "7.4. Enter the code received by $TELESIGN_PHONE : " TELESIGN_TEST_CODE
-      if test "${TELESIGN_TEST_CODE:-y}" != "12345"; then
-        say "Wrong code got '$TELESIGN_TEST_CODE' expected '12345', rerun this script to enter the right Telesign auth info"
-        exit 1
-      fi
-      echo "TELESIGN_AUTH_TOKEN=\"${TELESIGN_AUTH_TOKEN}\"" >>config/user.conf
-    fi
-    echo "DO_TELESIGN=${DO_TELESIGN}" >>config/user.conf
-  fi
-  if test -z "${BANK_ADMIN_PASSWORD:-}"; then
-    read -r -s -p "8. Enter the admin password for the bank (or press enter to autogenerate password): " BANK_ADMIN_PASSWORD
-    echo "BANK_ADMIN_PASSWORD=$(printf '%q' "${BANK_ADMIN_PASSWORD}")" >>config/user.conf
-    echo "" # force new line
-  fi
-}
-
-function normalize_currency() {
-  # convert to all-caps
-  local CURRENCY=$(echo "$1" | tr a-z A-Z)
-  # libeufin currenly doesn't like currency names less than 3 letters.
-  if [[ ${#CURRENCY} -lt 3 || ${#CURRENCY} -gt 11 ]]; then
-    say "Currency name must be between 3 and 10 letters"
-    exit 1
-  fi
-  echo "${CURRENCY}"
-}
-
-function check_dns() {
-  for prefix in "exchange" "bank" "backend"; do
-    if ! ping -c1 "${prefix}.${DOMAIN_NAME}" &>>setup.log; then
-      say "Could not ping ${prefix}.${DOMAIN_NAME}."
-      say "Please make sure your DNS/network are working."
-      exit 1
-    fi
-  done
-}
-
 # Set DISTRO to the detected distro or return non-zero
 # status if distro not supported.
 function detect_distro() {
diff --git a/regional-currency/main.sh b/regional-currency/main.sh
index 144fe5a..f7bc9e3 100755
--- a/regional-currency/main.sh
+++ b/regional-currency/main.sh
@@ -44,9 +44,9 @@ say "Installing packages (step 1 of 6)"
 
 say ""
 say "Interactive configuration (step 2 of 6)"
-ask_questions
+./ask_questions.py
+source config/user.conf
 
-check_dns
 # Remove when libeufin currencies.conf is in sync with exchange
 cat >>/usr/share/libeufin/config.d/netzbon.conf <<EOF
 [CURRENCY-NETZBON]
@@ -64,22 +64,10 @@ if test -z "${BANK_EXCHANGE_PASSWORD:-}"; then
   echo "BANK_EXCHANGE_PASSWORD=\"${BANK_EXCHANGE_PASSWORD}\"" >>config/internal.conf
 fi
 
-if test -z "${BANK_ADMIN_PASSWORD:-}"; then
-  BANK_ADMIN_PASSWORD=$(uuidgen)
-  echo "BANK_ADMIN_PASSWORD=\"${BANK_ADMIN_PASSWORD}\"" >>config/user.conf
-fi
-
 if test -z "${BANK_PORT:-}"; then
   echo "BANK_PORT=8080" >>config/user.conf
 fi
 
-if test "${ENABLE_TLS:-}" == "y"; then
-  PROTO="https"
-else
-  PROTO="http"
-fi
-echo "PROTO=${PROTO}" >>config/internal.conf
-
 say ""
 say "Configuring nginx (step 3 of 6)"
 ./config_nginx.sh
@@ -100,6 +88,7 @@ say "Setting up merchant (step 6 of 6)"
 say ""
 say "Congratulations, you have successfully installed GNU Taler"
 say "Your bank is at ${PROTO}://bank.${DOMAIN_NAME}/"
+say "You can connect to the bank web UI as 'admin' using '${BANK_ADMIN_PASSWORD}'"
 say "A merchant is at ${PROTO}://backend.${DOMAIN_NAME}/"
 say "You should set credentials for the merchant soon."