Multi-paths update and Geofire

[cmellinas]

Hi,

As mentioned here, I think it should be great to easily multi update data paths and a geofire path at the same time. As the set of Geofire is pretty complex, it's hard to directly copy/paste the code to make it works.

Here the use case : (I use the same as the link above but add a path to know where a post is located). So the structure :

{
  posts: {
    post1: {
      from : user1,
      message: "Hi",
    },
    post2: {
      from : user2,
      message: "Hey",
    }
  },
  posts-location: {
    post1: {
      g : 'xxxxxxxx',
      l: {
         0 : latitude,
         1 : longitude
      }
    },
    post2: {
       g : 'xxxxxxxx',
       l: {
         0 : latitude,
         1 : longitude
      }
    }
  },
  users: {
    user1: {
      posts: {
        post1: true
      }
    },
    user2: {
      posts: {
        post2: true
      }
    }
  }
}

Now I can add a post at the same time at users and posts (with multi-path update). But I need to set the position after. In my use case, a post without a position is not valid data, it's for that the best should be to do the 3 updates at the same times (if one fails, all fail).

Deleting Geofire path is easy (using update(null)), we can multi-update for delete, but for set/update, I loop for a way to do that easily,

Cheers,
Clément

[jwngr]

I think this is a great suggestion and I think we can find a way to work this into the API. It will be a little while before I have time to implement this, but I'm happy to code review PRs from the community. Otherwise, once I have some time to take a crack at this, I'll go ahead and see how we can support this kind of feature. Thanks for opening this issue!

[cmellinas]

Ah great Jacob
Hope you will found a solution

Many thanks,
Clément

[kz]

+1. Atomic updates are really important to ensure the integrity of the database.

[vikas-anvaya]

Do we have a solution for the problem now.

+1

maybe instead return _firebaseRef.update(newData); use return newData; ... then we can use ref().update function with other data

[jcheroske]

Playing fast and loose here, so disregard if this is totally whacked, but couldn't we just have a method that returns the geofire data that would be updated? Then we could just use the existing atomic update api.

[mversteeg3]

Any movement on this? I like @jcheroske's suggestion as long as there isn't any behind the scenes wizardry in the "set" method that would confound this solution

[deflexable]

checking the set function inside module at ../node_modules/geofire/dist/geofire/index.cjs.js" there wasn't really sophisticated method or external library that help update geofire hash to firebase. It's just plan method and validation.

as @ghost suggested earlier, instead of returning a promise for updating the data, you can simple return newData, then do the uploading yourself.

you can simply copy and paste below function, then you can do something like

`var map = {};
map['eventIndex/' + v] = getGeoFireHashes(eventKey, [location.lat, location.lon]);

firebase.database().ref('/').update(map);`

`function getGeoFireHashes(keyOrLocations, location) {
var locations;
if (typeof keyOrLocations === 'string' && keyOrLocations.length !== 0) {
// If this is a set for a single location, convert it into a object
locations = {};
locations[keyOrLocations] = location;
} else if (typeof keyOrLocations === 'object') {
if (typeof location !== 'undefined') {
throw new Error('The location argument should not be used if you pass an object to set().');
}
locations = keyOrLocations;
} else {
throw new Error('keyOrLocations must be a string or a mapping of key - location pairs.');
}
var newData = {};
Object.keys(locations).forEach(function (key) {
validateKey(key);
var location = locations[key];
if (location === null) {
// Setting location to null is valid since it will remove the key
newData[key] = null;
} else {
validateLocation(location);
var geohash = geohashForLocation(location);
newData[key] = encodeGeoFireObject(location, geohash);
}
});
return newData;
}

/**

• Encodes a location and geohash as a GeoFire object.
• @param location The location as [latitude, longitude] pair.
• @param geohash The geohash of the location.
• @returns The location encoded as GeoFire object.
  */
  function encodeGeoFireObject(location, geohash) {
  validateLocation(location);
  validateGeohash(geohash);
  return { '.priority': geohash, 'g': geohash, 'l': location };
  }

/**

• Generates a geohash of the specified precision/string length from the [latitude, longitude]
• pair, specified as an array.
• @param location The [latitude, longitude] pair to encode into a geohash.
• @param precision The length of the geohash to create. If no precision is specified, the
• global default is used.
• @returns The geohash of the inputted location.
  */
  function geohashForLocation(location, precision) {
  if (precision === void 0) { precision = GEOHASH_PRECISION; }
  validateLocation(location);
  if (typeof precision !== 'undefined') {
  if (typeof precision !== 'number' || isNaN(precision)) {
  throw new Error('precision must be a number');
  } else if (precision <= 0) {
  throw new Error('precision must be greater than 0');
  } else if (precision > 22) {
  throw new Error('precision cannot be greater than 22');
  } else if (Math.round(precision) !== precision) {
  throw new Error('precision must be an integer');
  }
  }
  var latitudeRange = {
  min: -90,
  max: 90
  };
  var longitudeRange = {
  min: -180,
  max: 180
  };
  var hash = '';
  var hashVal = 0;
  var bits = 0;
  var even = 1;
  while (hash.length < precision) {
  var val = even ? location[1] : location[0];
  var range = even ? longitudeRange : latitudeRange;
  var mid = (range.min + range.max) / 2;
  if (val > mid) {
  hashVal = (hashVal << 1) + 1;
  range.min = mid;
  } else {
  hashVal = (hashVal << 1) + 0;
  range.max = mid;
  }
  even = !even;
  if (bits < 4) {
  bits++;
  } else {
  bits = 0;
  hash += BASE32[hashVal];
  hashVal = 0;
  }
  }
  return hash;
  }

/**

• Validates the inputted geohash and throws an error if it is invalid.
• @param geohash The geohash to be validated.
  */
  function validateGeohash(geohash) {
  var error;
  if (typeof geohash !== 'string') {
  error = 'geohash must be a string';
  }
  else if (geohash.length === 0) {
  error = 'geohash cannot be the empty string';
  }
  else {
  for (var _i = 0, geohash_1 = geohash; _i < geohash_1.length; _i++) {
  var letter = geohash_1[_i];
  if (BASE32.indexOf(letter) === -1) {
  error = 'geohash cannot contain '' + letter + ''';
  }
  }
  }
  if (typeof error !== 'undefined') {
  throw new Error('Invalid GeoFire geohash '' + geohash + '': ' + error);
  }
  }

function validateKey(key) {
var error;
if (typeof key !== 'string') {
error = 'key must be a string';
}
else if (key.length === 0) {
error = 'key cannot be the empty string';
} else if (1 + GEOHASH_PRECISION + key.length > 755) {
// Firebase can only stored child paths up to 768 characters
// The child path for this key is at the least: 'i/key'
error = 'key is too long to be stored in Firebase';
} else if (/[[].#$/\u0000-\u001F\u007F]/.test(key)) {
// Firebase does not allow node keys to contain the following characters
error = 'key cannot contain any of the following characters: . # $ ] [ /';
}
if (typeof error !== 'undefined') {
throw new Error('Invalid GeoFire key '' + key + '': ' + error);
}
}

function validateLocation(location) {
var error;
if (!Array.isArray(location)) {
error = 'location must be an array';
}
else if (location.length !== 2) {
error = 'expected array of length 2, got length ' + location.length;
}
else {
var latitude = location[0];
var longitude = location[1];
if (typeof latitude !== 'number' || isNaN(latitude)) {
error = 'latitude must be a number';
}
else if (latitude < -90 || latitude > 90) {
error = 'latitude must be within the range [-90, 90]';
}
else if (typeof longitude !== 'number' || isNaN(longitude)) {
error = 'longitude must be a number';
}
else if (longitude < -180 || longitude > 180) {
error = 'longitude must be within the range [-180, 180]';
}
}
if (typeof error !== 'undefined') {
throw new Error('Invalid GeoFire location '' + location + '': ' + error);
}
}`