stitch-ui/src/services/mongodb/validation.js

const DISALLOWED_NS_CHARS = ["/", "\\", ".", "\u0000", "$"];
const DISALLOWED_NS_COLLECTION_CHARS = ["/", "\\", "\u0000", "$"];
const DISALLOWED_FIELD_CHARS = ["$", "\u0000"];
const INVALID_DB_NAMES = ["system", "local", "admin"];

// Returns false if the string contains any of the set of characters
// not allowed in DB or collection names.
export const validateDisallowedChars = (s, disallowedCharSet) =>
  !disallowedCharSet.some(illegalChar => s.indexOf(illegalChar) >= 0);

export const validateCollectionName = cName => {
  if (cName.length === 0) {
    return "Collection name cannot be blank";
  }
  if (cName.indexOf("system.") === 0) {
    return "Collection names may not be prefixed with 'system.'";
  }

  if (cName[0] === ".") {
    return `Collection names may not start with '.'`;
  }

  if (!validateDisallowedChars(cName, DISALLOWED_NS_COLLECTION_CHARS)) {
    return "Collection name contains illegal characters";
  }

  return null;
};

// TODO perform this validation on the backend.
export const validateDBName = dbName => {
  if (dbName.length === 0) {
    return "Database name must not be empty";
  }
  if (dbName.length > 63) {
    return "Database name is too long";
  }

  if (INVALID_DB_NAMES.includes(dbName)) {
    return `Database name may not be '${dbName}'`;
  }

  if (!validateDisallowedChars(dbName, DISALLOWED_NS_CHARS)) {
    return "Database name contains illegal characters";
  }
  return null;
};

export const validateNamespace = n => {
  if (n.length > 122) {
    return "Namespace is too long.";
  }

  // find the first instance of "." in the namespace
  const firstDotIndex = n.indexOf(".");
  if (firstDotIndex === 0) {
    return "Namespace cannot begin with '.'";
  } else if (firstDotIndex === n.length - 1) {
    return "Namespace cannot end with '.'";
  } else if (firstDotIndex < 0) {
    return "Namespace must contain a '.' to separate database and collection.";
  }
  const dbName = n.substring(0, firstDotIndex);
  const collectionName = n.substring(firstDotIndex + 1);

  const dbErr = validateDBName(dbName);
  if (dbErr) {
    return dbErr;
  }
  const cErr = validateCollectionName(collectionName);
  if (cErr) {
    return cErr;
  }
  return null;
};

export const validateFieldName = fName => {
  if (fName.length === 0) {
    return "Field name may not be empty.";
  }
  if (!validateDisallowedChars(fName, DISALLOWED_FIELD_CHARS)) {
    return "Field name contains illegal characters";
  }
  return null;
};