Can't save and delete in a transaction

[susanlinsfu]

I asked this question on stackoverflow, but am also posting here as an issue (http://stackoverflow.com/questions/37401751/cant-save-and-delete-in-a-transaction).

var cachedTransaction;
datastore.runInTransaction(function(transaction, done) {
            cachedTransaction = transaction;

            var keys = [
                datastore.key([PARENT_TABLE, p1]),
                datastore.key([PARENT_TABLE, p2]),
                datastore.key([PARENT_TABLE, p1, CHILD_TABLE, p2])
            ];

            transaction.get(keys, function(err, entities) {

                    if (err) {
                        transaction.rollback();
                    }

                    if (entities) {
                        transaction.save([{
                            key: datastore.key([PARENT_TABLE, p1]),
                            method: 'update',
                            data: {
                                p: 100
                            }
                        }, {
                            key: datastore.key([config.PARENT_TABLE, p2]),
                            method: 'update',
                            data: {
                                p: 100
                            }
                        }]);

                        transaction.delete([

                            datastore.key([PARENT_TABLE, p1, CHILD_TABLE, p2]),
                            datastore.key([PARENT_TABLE, p2, CHILD_TABLE, p1])

                        ]);

                    } else {
                        console.log('Entities are empty');
                    }
                    console.log('commiting ... ');
                    done();
                    console.log('commited ');

                } else {
                    transaction.rollback();
                }
            });

    },
    function(err) {
        console.log('commited complete. Was it successful ? ');
        if (err) {
            console.log('err : ' + err);
            cachedTransaction.rollback();
        }
    });

With the following code I am getting two entities from a parent table and one entity from a child table (I print some stuff with this child entity not shown in code). I then update the two parent entities and delete two child entities (one which I did not get get from my original response). The result is that the parent entities do get updated, but the two children entities do NOT get deleted. I get no error messages.

If I comment out the save portion of the code which updated the parents, then it will delete the child entities, but I need to update the parent and delete the children. How can I do this? I am using gcloud-node 0.34.0 and running off the actual Google Cloud Datastore.

Thanks!

[stephenplusplus]

@pcostell could you give this one a quick look to make sure things look correct?

Here's the script I've tested with:

'use strict';

var gcloud = require('gcloud');
var datastore = gcloud.datastore();

var PARENT_TABLE = 'Parent';
var CHILD_TABLE = 'Child';

var p1 = 'pname1';
var p2 = 'pname2';

insertInitialData(runTransaction);

function insertInitialData(callback) {
  datastore.save([
    {
      key: datastore.key([PARENT_TABLE, p1]),
      data: {
        p: 0
      }
    },
    {
      key: datastore.key([PARENT_TABLE, p2]),
      data: {
        p: 0
      }
    },
    {
      key: datastore.key([PARENT_TABLE, p1, CHILD_TABLE, p2]),
      data: {
        p: 0
      }
    },
    {
      key: datastore.key([PARENT_TABLE, p2, CHILD_TABLE, p1]),
      data: {
        p: 0
      }
    }
  ], callback);
}

function runTransaction() {
  var keysToGet = [
    datastore.key([PARENT_TABLE, p1]),
    datastore.key([PARENT_TABLE, p2]),
    datastore.key([PARENT_TABLE, p1, CHILD_TABLE, p2])
  ];

  var keysToDelete = [
    keysToGet[2],
    datastore.key([PARENT_TABLE, p2, CHILD_TABLE, p1])
  ];

  var keysToUpdate = [
    datastore.key([PARENT_TABLE, p1]),
    datastore.key([PARENT_TABLE, p2])
  ];

  datastore.runInTransaction(function(transaction, done) {
    transaction.get(keysToGet, function(err, entities) {
      if (err) {
        transaction.rollback();
        done();
        return;
      }

      if (entities.length === 0) {
        console.log('Entities are empty');
        done();
        return;
      }

      transaction.save([{
        key: keysToUpdate[0],
        method: 'update',
        data: {
          p: 100
        }
      }, {
        key: keysToUpdate[1],
        method: 'update',
        data: {
          p: 100
        }
      }]);

      transaction.delete(keysToDelete);

      done();
    });
  }, function(err) {
    if (err) {
      throw err;
    }

    datastore.get(keysToUpdate, function(err, entities) {
      if (err) {
        throw err;
      }

      console.log('Updated entities?', entities.every(function(entity) {
        return entity.data.p === 100;
      }));

      datastore.get(keysToDelete, function(err, entities) {
        if (err) {
          throw err;
        }

        console.log('Deleted entities?', entities.length === 0);
      });
    });
  });
}

Running returns:

Updated entities? true
Deleted entities? false

And the commit request that gets sent when done() (commit) is called.

{
  "mutations": [
    {
      "delete": {
        "path": [
          {
            "kind": "Parent",
            "name": "pname1"
          },
          {
            "kind": "Child",
            "name": "pname2"
          }
        ]
      },
      "update": {
        "key": {
          "path": [
            {
              "kind": "Parent",
              "name": "pname1"
            }
          ]
        },
        "properties": {
          "p": {
            "integerValue": 100
          }
        }
      }
    },
    {
      "delete": {
        "path": [
          {
            "kind": "Parent",
            "name": "pname2"
          },
          {
            "kind": "Child",
            "name": "pname1"
          }
        ]
      },
      "update": {
        "key": {
          "path": [
            {
              "kind": "Parent",
              "name": "pname2"
            }
          ]
        },
        "properties": {
          "p": {
            "integerValue": 100
          }
        }
      }
    }
  ]
}

[pcostell]

@stephenplusplus That seems odd. One thing to double check, is that the full commit message? Because I don't see any transaction specified there.

[stephenplusplus]

Yes, that was just the mutations part, sorry. The full thing is here:

{
  "mutations": [
    {
      "delete": {
        "path": [
          {
            "kind": "Parent",
            "name": "pname1"
          },
          {
            "kind": "Child",
            "name": "pname2"
          }
        ]
      },
      "update": {
        "key": {
          "path": [
            {
              "kind": "Parent",
              "name": "pname1"
            }
          ]
        },
        "properties": {
          "p": {
            "integerValue": 100
          }
        }
      }
    },
    {
      "delete": {
        "path": [
          {
            "kind": "Parent",
            "name": "pname2"
          },
          {
            "kind": "Child",
            "name": "pname1"
          }
        ]
      },
      "update": {
        "key": {
          "path": [
            {
              "kind": "Parent",
              "name": "pname2"
            }
          ]
        },
        "properties": {
          "p": {
            "integerValue": 100
          }
        }
      }
    }
  ],
  "projectId": "nth-circlet-705",
  "mode": "TRANSACTIONAL",
  "transaction": "EQA6Wuslj8Q/IlkAM9qycvuHuvP30Lxax8rLQToFhMqIJzOwWishYI7n2zQxHpmybeKYoNjQ8zjTA/7s8eXQizRmcLQJr/R1wURemBZpMlg5FzSMTAXQ7JxwU+1/PI96X/C0eg=="
}

[pcostell]

Ah it looks like your mutations are being created incorrectly. In particular, you only have two mutations, each one with an upsert and a delete.

The way proto oneof fields work, it will only ever accept the last one set.

[stephenplusplus]

Ah, okay, so just confirming, it should be:

mutations = [
  { delete: {} },
  { upsert: {} },
  { delete: {} },
  { upsert: {} }
]

[stephenplusplus]

PR sent with a fix: #1341

[stephenplusplus]

Released in 0.35.0.