You can install neo4j-doc-manager from Github source:

First, install the project dependencies:

Now install neo4j_doc_manager by cloning this repository and setting the PYTHONPATH to it’s local directory:

If you have authentication enabled for Neo4j, be sure to set NEO4J_AUTH environment variable, containing your username and password.

If authentication is not enabled on Neo4j, no action is required. To disable authentication on Neo4j, go to Neo4j install directory, and then edit conf/neo4j-server.properties :

We then run the following statement into mongo, to insert a talk into a collection of talks:

This will insert the following document into Mongo:

This will be reflected as follows into Neo4j:

Check the detailed generated graph:

Created nodes:

Also, for every created node, a property names _ts, representing the timestamp of the creation in MongoBD, is added to the node.

Created Relationships:

The node chain is preserved. For example, imagine that you insert the following document in MongoDB:

In Neo4j, we will have:

Created nodes:

Also, for every created node, a property names _ts, representing the timestamp of the creation in MongoBD, is added to the node.

Created Relationships:

Now let’s insert the following data. Note the nested JSON array represented by tracks:

The above document will be translated into Neo4j as follows:

Created nodes:

Created Relationships:

Let’s imagine now an explicit _id reference between two documents, such as:

Note that two documents were inserted, and people references place explicitly by id. Neo4j Doc Manager will map every field that ends with _id into an explicit relationship. First, we run a MERGE to see if the respective node exists. In the above example, we insert a _place_, and then a people. When inserting the people type, the connector will identify an explicit id relationship, through places\_id , and will try to find the respective node. If it does exist (and it should), a relationship between the two nodes will be created.

Created nodes:

Created Relationships:

$set clause updates a single document. For example, imagine we have inserted the talks previously described into Upsert section, and now we want to update the room, which is Auditorium, to Auditorium2. We have to run the following instruction:

This instruction will get the first document in Mongo that matches with the specified criteria and generate an update method call into Neo4j Doc Manager. Considering we have a document previously inserted into Mongo by the Upsert example, we will have a single update.

Updated Nodes

Compare both graphs:

Before the update

After the update

Let’s assume we have inserted another talk in Mongo:

Note that both talks should be held at Auditorium2. If we run the following command:

Only the first document found by Mongo will be updated, as shown on the image below.

If we want to change all documents, we must use multi parameter, described in the following section.

Many properties can be changed with a single update clause. For example, if we run

We will have both properties, room and timeslot, updated into the graph.

$unset clause updates a single document by removing a property on a document. For example, imagine we have inserted the talks previously described into Upsert section, and now we want to remove the timeslot property for the talk that has its room as Auditorium. We have to run the following instruction:

Compare both graphs:

Before the update

After the update

This instruction will get the first document in Mongo that matches with the specified criteria and generate an update method call into Neo4j Doc Manager. Considering we have a document previously inserted into Mongo by the Upsert example, we will have a single update, removing the property (notice on the node on the left side of the image).

Updated Nodes by removing a property

Only the first document found by Mongo will be updated and have timeslot property removed. If we want to change all documents, we must use multi parameter, described in the following section.

Many properties can be changed with a single update clause. For example, if we run

We will have both properties, room and timeslot, removed of the node into the graph.

$unset can also remove connected nodes and relationships. Assuming our default talks example:

If we run:

In Neo4j it will cause a removal of the node with the label session for the room with the property Auditorium and also the removal os the relationship connecting talks and session.

It is also possible to update a document by specifying the entire change desired on it. For example, imagine we have inserted the talks previously described into Upsert section.

Now we want to update the document to select the one whose room will be Auditorium and clear all the root data and have only a property called level, which value will be intermediate. We have to run the following instruction:

This instruction will get the first document in Mongo that matches with the specified criteria and generate an update method call into Neo4j Doc Manager. Considering we have a document previously inserted into Mongo by the Upsert example, we will have a single update.

Updated Nodes

Updated Relationships

Note: Calling an update clause without $set or $unset will lead to property overriding, not concatenating with the existing ones.

It is also possible to run an update clause that contains a nested document as an argument. Imagine our default talks example:

Then we run:

This instruction will remove all the properties from the talks node (but it will still being the root node). A new node, with the label conference, will be created. Also, a relationship between talks and conference will be made:

Updated Nodes

Updated Relationships

We can also run a composite update clause where we create a new node and also update the root node:

This instruction will remove all the properties from the talks node (but it will still be the root node). It will also create a level property on talks, with intermediate value. A new node, with the label conference, will be created. Also, a relationship between talks and conference will be made:

Updated Nodes

Updated Relationships

We can update all the documents that match to a following criteria. Following the example above, to update all document rooms to Auditorium, we should run:

multi: true will update all documents that match the specified clauses. This behaviour will also be reflected into Neo4j - all Nodes will be updated. So, if before the clause we had:

Before the update:

After the update:

Nodes

After running the update clause with multi parameter, we end up with:

Updated Nodes

Update clauses also can be used for inserting new properties into documents. This will result in a new property for a node. Let’s assume the talks previously inserted. Let’s set a level property for all the talks that will happen into Auditorium room, pointing that they require an intermediate level. Before running the update clause, we have the following into Neo4j graph:

After running the update clause, we have:

Let’s assume the graph below:

If the update clause does not match any document, by default a new document is not created. However, if you pass the parameter {upsert: true}, a new document is created. For example, assume we run the following clause:

At the moment we do not have any document that matches with room Auditorium4. If we do not specify anything, nothing is done to Mongo or Neo4j and we end up with a graph identical to the initial one:

However, if we specify the upsert as a true parameter,

a new document will be inserted into Mongo and a new group of nodes and relationships will be inserted into Neo4j. So, after running the above query, we will have:

Updated nodes

Inserted nodes

We can also invoke an update action that contains a nested Document. For example, imagine that we have the following document in Mongo, that we have been using in the past examples:

In Neo4j, we have:

Nodes:

Relationships:

And then we run the following instruction:

This will cause the following update in Mongo:

Note that the nested document conference has been inserted. This will be translated as a new node and a new relationship into Neo4j:

Created by update action Nodes:

Created by update action Relationchips:

When a node will be removed, the nodes created from nested documents will also be removed. Also, all the relationships between these nodes will be deleted, to avoid orphans.

It is also possible to specify a document parameter that refers to the document that we want to remove. For example, we can run:

This will remove a single document with room marked as Auditorium.

Before the update:

After the update:

The translation will be held the same way for Neo4j - The corresponding Document::talks node will be removed with all his nested information.

Imagine that we have the following document:

You can notice that we have nested documents. We can specify only the root level fields that will be imported. For example:

In Neo4j, we will have:

Nodes

Note that the nested node speaker was not imported to Neo4j, nor the root level properties topics and timeslot.

Relationships