Block remote Prisma and Drizzle wipes in Cursor

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{
  "version": 1,
  "hooks": {
    "beforeShellExecution": [
      {
        "command": ".cursor/hooks/block-remote-migrate.sh",
        "timeout": 10,
        "failClosed": true,
        "matcher": "prisma|drizzle-kit"
      }
    ]
  }
}

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#!/bin/sh
# Free Cursor hook: block prisma migrate reset and drizzle-kit push --force
# when the target database URL is not local.
# Derived from Schema Migration Guard v1.3 hooks/block-destructive-migrate.sh
# (command scan only; no Claude Code payload, no db drop / drizzle reset).
# Docs: https://cursor.com/docs/hooks
#
# Blocked (when the URL is not local):
#   prisma migrate reset
#   drizzle-kit push --force  (or push with a force flag such as -f)
# Local URLs still run: localhost, 127.0.0.1, ::1, file:, sqlite:, sqlite3:
# URL sources: --url on the command, DATABASE_URL / DIRECT_URL in the hook
# environment, then .env / .env.local in the payload cwd.

set -eu

json_escape() {
  printf '%s' "$1" | awk '
    BEGIN { ORS = "" }
    {
      n = length($0)
      for (i = 1; i <= n; i++) {
        c = substr($0, i, 1)
        if (c == "\\") printf "\\\\"
        else if (c == "\"") printf "\\\""
        else if (c == "\n") printf "\\n"
        else if (c == "\r") printf "\\r"
        else if (c == "\t") printf "\\t"
        else printf "%s", c
      }
    }
  '
}

extract_string_field() {
  key=$1
  printf '%s' "$2" | awk -v key="$key" '
    function skip_ws(s) {
      while (s ~ /^[ \t\n\r]/) s = substr(s, 2)
      return s
    }
    function parse_string(s,    c, out, esc) {
      out = ""
      esc = 0
      while (length(s) > 0) {
        c = substr(s, 1, 1)
        s = substr(s, 2)
        if (esc) {
          if (c == "n") out = out "\n"
          else if (c == "t") out = out "\t"
          else if (c == "r") out = out "\r"
          else out = out c
          esc = 0
          continue
        }
        if (c == "\\") { esc = 1; continue }
        if (c == "\"") {
          RESULT = out
          REST = s
          return 1
        }
        out = out c
      }
      return 0
    }
    BEGIN { needle = "\"" key "\"" }
    {
      s = $0
      while ((i = index(s, needle)) > 0) {
        rest = skip_ws(substr(s, i + length(needle)))
        if (substr(rest, 1, 1) != ":") {
          s = substr(s, i + 1)
          continue
        }
        rest = skip_ws(substr(rest, 2))
        if (substr(rest, 1, 1) != "\"") {
          s = substr(s, i + 1)
          continue
        }
        if (parse_string(substr(rest, 2))) {
          print RESULT
          exit 0
        }
        s = substr(s, i + 1)
      }
    }
  '
}

split_segments() {
  printf '%s' "$1" | awk '
    BEGIN { token = "" }
    function flush() {
      gsub(/^[ \t\n\r]+|[ \t\n\r]+$/, "", token)
      if (token != "") print token
      token = ""
    }
    {
      line = $0
      n = length(line)
      i = 1
      in_squote = 0
      in_dquote = 0
      while (i <= n) {
        c = substr(line, i, 1)
        nextc = substr(line, i + 1, 1)
        if (in_squote) {
          token = token c
          if (c == "'\''") in_squote = 0
          i++
          continue
        }
        if (in_dquote) {
          token = token c
          if (c == "\\") {
            if (i < n) {
              token = token nextc
              i += 2
              continue
            }
          }
          if (c == "\"") in_dquote = 0
          i++
          continue
        }
        if (c == "'\''") { in_squote = 1; token = token c; i++; continue }
        if (c == "\"") { in_dquote = 1; token = token c; i++; continue }
        if (c == "\n" || c == ";" || c == "|" || c == "&") {
          if ((c == "|" && nextc == "|") || (c == "&" && nextc == "&")) {
            flush()
            i += 2
            continue
          }
          if (c == "|" || c == "&" || c == ";" || c == "\n") {
            flush()
            i++
            continue
          }
        }
        token = token c
        i++
      }
      flush()
    }
  '
}

tokenize() {
  printf '%s' "$1" | awk '
    {
      line = $0
      n = length(line)
      i = 1
      token = ""
      in_squote = 0
      in_dquote = 0
      while (i <= n) {
        c = substr(line, i, 1)
        nextc = substr(line, i + 1, 1)
        if (in_squote) {
          if (c == "'\''") in_squote = 0
          else token = token c
          i++
          continue
        }
        if (in_dquote) {
          if (c == "\\") {
            i++
            if (i <= n) token = token substr(line, i, 1)
            i++
            continue
          }
          if (c == "\"") in_dquote = 0
          else token = token c
          i++
          continue
        }
        if (c == "'\''") { in_squote = 1; i++; continue }
        if (c == "\"") { in_dquote = 1; i++; continue }
        if (c == " " || c == "\t") {
          if (token != "") { print token; token = "" }
          i++
          continue
        }
        token = token c
        i++
      }
      if (token != "") print token
    }
  '
}

strip_prefixes() {
  awk '
    function is_runner(t) {
      return (t == "npx" || t == "pnpm" || t == "yarn" || t == "bunx" || t == "bun" || t == "npm")
    }
    function is_sub(t) {
      return (t == "exec" || t == "dlx" || t == "x")
    }
    function is_wrap(t) {
      return (t == "env" || t == "command" || t == "exec" || t == "sudo" || t == "time" || t == "nice" || t == "nohup")
    }
    function is_assign(t) {
      return (t ~ /^[A-Za-z_][A-Za-z0-9_]*=/)
    }
    function is_flag(t) {
      return (t == "--" || t ~ /^-/)
    }
    function skip_flags() {
      while (i <= NR && is_flag(lines[i])) {
        if (lines[i] == "-p" || lines[i] == "--package") {
          i++
          if (i <= NR && !is_flag(lines[i])) i++
          continue
        }
        i++
      }
    }
    {
      lines[NR] = $0
    }
    END {
      i = 1
      progressed = 1
      while (progressed && i <= NR) {
        progressed = 0
        while (i <= NR && is_assign(lines[i])) { i++; progressed = 1 }
        while (i <= NR && is_wrap(lines[i])) {
          i++
          while (i <= NR && (is_flag(lines[i]) || is_assign(lines[i]))) i++
          progressed = 1
        }
        while (i <= NR && is_runner(lines[i])) {
          i++
          skip_flags()
          if (i <= NR && is_sub(lines[i])) {
            i++
            skip_flags()
          }
          progressed = 1
        }
      }
      for (; i <= NR; i++) print lines[i]
    }
  '
}

unwrap_shell_c() {
  awk '
    function base(t,    n, p) {
      n = split(t, p, "/")
      t = p[n]
      split(t, p, "@")
      return p[1]
    }
    function is_shell(t,    b) {
      b = base(t)
      return (b == "sh" || b == "bash" || b == "zsh")
    }
    function is_flag(t) {
      return (t == "--" || t ~ /^-/)
    }
    function is_c_flag(t) {
      if (t == "-c") return 1
      if (t ~ /^-[a-zA-Z]*c[a-zA-Z]*$/ && t !~ /^--/) return 1
      return 0
    }
    {
      tok[++n] = $0
    }
    END {
      i = 1
      if (i > n || !is_shell(tok[i])) exit 0
      i++
      while (i <= n) {
        if (is_c_flag(tok[i])) {
          if (i + 1 <= n) print tok[i + 1]
          exit 0
        }
        if (is_flag(tok[i])) { i++; continue }
        exit 0
      }
    }
  '
}

reason_for_segment() {
  awk '
    function base(t,    n, p) {
      n = split(t, p, "/")
      t = p[n]
      split(t, p, "@")
      return p[1]
    }
    function is_flag(t) {
      return (t == "--" || t ~ /^-/)
    }
    function drizzle_force(t) {
      return (t == "--force" || index(t, "--force=") == 1 || t == "-f")
    }
    {
      tok[++n] = $0
    }
    END {
      i = 1
      while (i <= n && is_flag(tok[i])) i++
      if (i > n) exit 0
      kind = base(tok[i])
      start = i
      if (kind != "prisma" && kind != "drizzle-kit") exit 0

      for (i = start; i <= n; i++) {
        if (!is_flag(tok[i])) words[++w] = base(tok[i])
      }

      if (kind == "prisma") {
        if (w >= 3 && words[1] == "prisma" && words[2] == "migrate" && words[3] == "reset") {
          print "prisma_reset"
          exit 0
        }
      }

      if (kind == "drizzle-kit") {
        if (w >= 2 && words[1] == "drizzle-kit" && words[2] == "push") {
          for (i = start; i <= n; i++) {
            if (drizzle_force(tok[i])) {
              print "drizzle_force"
              exit 0
            }
          }
        }
      }
    }
  '
}

urls_from_command() {
  tokenize "$1" | awk '
    {
      tok[++n] = $0
    }
    END {
      for (i = 1; i <= n; i++) {
        t = tok[i]
        if (index(t, "DATABASE_URL=") == 1) {
          print substr(t, 14)
          continue
        }
        if (index(t, "DIRECT_URL=") == 1) {
          print substr(t, 12)
          continue
        }
        if (index(t, "--url=") == 1) {
          print substr(t, 7)
          continue
        }
        if (t == "--url" && i < n) {
          print tok[i + 1]
          i++
        }
      }
    }
  '
}

read_env_file_var() {
  file=$1
  key=$2
  [ -f "$file" ] || return 0
  awk -v key="$key" '
    {
      line = $0
      sub(/\r$/, "", line)
      sub(/^[ \t]+/, "", line)
      if (line == "" || line ~ /^#/) next
      if (index(line, "export ") == 1) {
        line = substr(line, 8)
        sub(/^[ \t]+/, "", line)
      }
      eq = index(line, "=")
      if (eq < 2) next
      k = substr(line, 1, eq - 1)
      gsub(/[ \t]+$/, "", k)
      if (k != key) next
      v = substr(line, eq + 1)
      sub(/^[ \t]+/, "", v)
      if (v ~ /^"/) {
        v = substr(v, 2)
        if (v ~ /"$/) v = substr(v, 1, length(v) - 1)
      } else if (v ~ /^'\''/) {
        v = substr(v, 2)
        if (v ~ /'\''$/) v = substr(v, 1, length(v) - 1)
      } else {
        sub(/[ \t]+(#.*)?$/, "", v)
      }
      print v
      exit 0
    }
  ' "$file"
}

url_kind() {
  printf '%s' "$1" | awk '
    function last_at(s,    i, p) {
      p = 0
      for (i = 1; i <= length(s); i++) if (substr(s, i, 1) == "@") p = i
      return p
    }
    {
      raw = $0
      gsub(/^[ \t\n\r]+|[ \t\n\r]+$/, "", raw)
      if (raw == "") { print "unknown"; exit 0 }
      u = tolower(raw)
      if (u ~ /^(file|sqlite|sqlite3):/) { print "local"; exit 0 }
      q = index(u, "?")
      if (q > 0) u = substr(u, 1, q - 1)
      sep = index(u, "://")
      if (sep < 1) { print "remote"; exit 0 }
      rest = substr(u, sep + 3)
      at = last_at(rest)
      hostport = (at > 0) ? substr(rest, at + 1) : rest
      p = index(hostport, "/")
      if (p > 0) hostport = substr(hostport, 1, p - 1)
      if (hostport ~ /^\[/) {
        closebr = index(hostport, "]")
        host = (closebr > 1) ? substr(hostport, 2, closebr - 2) : hostport
      } else {
        c = index(hostport, ":")
        host = (c > 0) ? substr(hostport, 1, c - 1) : hostport
      }
      if (host == "localhost" || host == "127.0.0.1" || host == "::1" || host == "0.0.0.0") {
        print "local"
        exit 0
      }
      print "remote"
    }
  '
}

collect_target_urls() {
  command=$1
  cwd=$2
  urls=$(urls_from_command "$command" || true)
  if [ -n "$urls" ]; then
    printf '%s\n' "$urls"
    return 0
  fi
  if [ -n "${DATABASE_URL-}" ]; then
    printf '%s\n' "$DATABASE_URL"
    return 0
  fi
  if [ -n "${DIRECT_URL-}" ]; then
    printf '%s\n' "$DIRECT_URL"
    return 0
  fi
  if [ -n "$cwd" ]; then
    for f in "$cwd/.env" "$cwd/.env.local"; do
      v=$(read_env_file_var "$f" DATABASE_URL || true)
      if [ -z "$v" ]; then
        v=$(read_env_file_var "$f" DIRECT_URL || true)
      fi
      if [ -n "$v" ]; then
        printf '%s\n' "$v"
        return 0
      fi
    done
  fi
}

is_local_target() {
  urls=$(collect_target_urls "$1" "$2" || true)
  if [ -z "$urls" ]; then
    return 1
  fi
  printf '%s\n' "$urls" | while IFS= read -r url || [ -n "$url" ]; do
    [ -z "$url" ] && continue
    kind=$(url_kind "$url" || true)
    if [ "$kind" != "local" ]; then
      exit 1
    fi
  done
}

classify() {
  command="$1"
  depth=${2:-0}
  if [ -z "$command" ]; then
    printf '%s' ""
    return 0
  fi
  if [ "$depth" -gt 16 ]; then
    printf '%s' ""
    return 0
  fi

  split_segments "$command" | while IFS= read -r seg || [ -n "$seg" ]; do
    [ -z "$seg" ] && continue
    stripped=$(tokenize "$seg" | strip_prefixes || true)
    [ -z "$stripped" ] && continue
    inner=$(printf '%s\n' "$stripped" | unwrap_shell_c || true)
    if [ -n "$inner" ]; then
      seg_reason=$(classify "$inner" $((depth + 1)) || true)
    else
      seg_reason=$(printf '%s\n' "$stripped" | reason_for_segment || true)
    fi
    if [ -n "$seg_reason" ]; then
      printf '%s' "$seg_reason"
      break
    fi
  done
}

deny_text() {
  case "$1" in
    prisma_reset)
      printf '%s' "This Prisma reset was blocked because the database URL is not local (localhost, 127.0.0.1, file, or sqlite)."
      ;;
    drizzle_force)
      printf '%s' "This forced Drizzle push was blocked because the database URL is not local (localhost, 127.0.0.1, file, or sqlite)."
      ;;
    *)
      printf '%s' "This Prisma or Drizzle command was blocked because the database URL is not local."
      ;;
  esac
}

input=$(cat || true)
command=$(extract_string_field command "$input" || true)
cwd=$(extract_string_field cwd "$input" || true)
reason=$(classify "$command" || true)

if [ -z "$reason" ]; then
  printf '%s\n' '{"permission":"allow"}'
  exit 0
fi

if is_local_target "$command" "$cwd"; then
  printf '%s\n' '{"permission":"allow"}'
  exit 0
fi

msg=$(deny_text "$reason")
escaped=$(json_escape "$msg")
printf '%s\n' "{\"permission\":\"deny\",\"user_message\":\"${escaped}\",\"agent_message\":\"${escaped}\"}"
exit 0