README.md

pipelinewise-tap-mongodb

This is a Singer tap that produces JSON-formatted data following the Singer spec from a MongoDB source.

Custom setup

• install with meltano add --custom extractor tap-mongodb
  • namespace: tap-mongodb
  • pip_url: git+https://github.com/JamieSplitit/pipelinewise-tap-mongodb.git
  • executable name: tap-mongodb
  • capabilities: state,catalog,discover,log-based
  • settings: password,user,host,auth_database,database,srv,port:integer,replica_set,ssl,verify_mode,include_schemas_in_destination_stream_name,update_buffer_size:integer,await_time_ms:integer

Set up local dev environment:

make setup

Activate virtual environment

. venv/bin/activate

Set up Config file

Create json file called config.json, with the following contents:

{
  "password": "<password>",
  "user": "<username>",
  "host": "<host ip address>",
  "auth_database": "<database name to authenticate on>",
  "database": "<database name to sync from>"
}

The following parameters are optional for your config file:

Name	Type	Default value	Description
srv	Boolean	false	uses a mongodb+srv protocol to connect. Disables the usage of port argument if set to True
port	Integer	false	Connection port. Required if a non-srv connection is being used.
replica_set	string	null	name of replica set
ssl	Boolean	false	can be set to true to connect using ssl
verify_mode	Boolean	true	Default SSL verify mode
include_schemas_in_destination_stream_name	Boolean	false	forces the stream names to take the form <database_name>-<collection_name> instead of <collection_name>
update_buffer_size	int	1	[LOG_BASED] The size of the buffer that holds detected update operations in memory, the buffer is flushed once the size is reached
await_time_ms	int	1000	[LOG_BASED] The maximum amount of time in milliseconds the loge_base method waits for new data changes before exiting.

All of the above attributes are required by the tap to connect to your mongo instance. here is a sample configuration file.

Run in discovery mode

Run the following command and redirect the output into the catalog file

tap-mongodb --config ~/config.json --discover > ~/catalog.json

Your catalog file should now look like this:

{
  "streams": [
    {
      "table_name": "<table name>",
      "tap_stream_id": "<tap_stream_id>",
      "metadata": [
        {
          "breadcrumb": [],
          "metadata": {
            "row-count":<int>,
            "is-view": <bool>,
            "database-name": "<database name>",
            "table-key-properties": [
              "_id"
            ],
            "valid-replication-keys": [
              "_id"
            ]
          }
        }
      ],
      "stream": "<stream name>",
      "schema": {
        "type": "object"
      }
    }
  ]
}

Edit Catalog file

Using valid json, edit the config.json file

To select a stream, enter the following to the stream's metadata:

"selected": true,
"replication-method": "<replication method>",

<replication-method> must be either FULL_TABLE, INCREMENTAL or LOG_BASED, if it's INCREMENTAL, make sure to add a "replication-key".

For example, if you were to edit the example stream to select the stream as well as add a projection, config.json should look this:

{
  "streams": [
    {
      "table_name": "<table name>",
      "tap_stream_id": "<tap_stream_id>",
      "metadata": [
        {
          "breadcrumb": [],
          "metadata": {
            "row-count": <int>,
            "is-view": <bool>,
            "database-name": "<database name>",
            "table-key-properties": [
              "_id"
            ],
            "valid-replication-keys": [
              "_id"
            ],
            "selected": true,
            "replication-method": "<replication method>"
          }
        }
      ],
      "stream": "<stream name>",
      "schema": {
        "type": "object"
      }
    }
  ]
}

Run in sync mode:

tap-mongodb --config ~/config.json --catalog ~/catalog.json

The tap will write bookmarks to stdout which can be captured and passed as an optional --state state.json parameter to the tap for the next sync.

Logging configuration

The tap uses a predefined logging config if none is provided, however, you can set your own config by setting the environment variable LOGGING_CONFIG_FILE as the path to the logging config. A sample config is available here.

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