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A Singer target that writes data to JSONL (JSON Lines) files.

How to use it

target-jsonl works together with any other Singer Tap to move data from sources like Braintree, Freshdesk and Hubspot to JSONL formatted files.


We will use tap-exchangeratesapi to pull currency exchange rate data from a public data set as an example.

First, make sure Python 3 is installed on your system or follow these installation instructions for Mac or Ubuntu.

It is recommended to install each Tap and Target in a separate Python virtual environment to avoid conflicting dependencies between any Taps and Targets.

 # Install tap-exchangeratesapi in its own virtualenv
python3 -m venv ~/.virtualenvs/tap-exchangeratesapi
source ~/.virtualenvs/tap-exchangeratesapi/bin/activate
pip install tap-exchangeratesapi

# Install target-jsonl in its own virtualenv
python3 -m venv ~/.virtualenvs/target-jsonl
source ~/.virtualenvs/target-jsonl/bin/activate
pip install target-jsonl


We can now run tap-exchangeratesapi and pipe the output to target-jsonl.

~/.virtualenvs/tap-exchangeratesapi/bin/tap-exchangeratesapi | ~/.virtualenvs/target-jsonl/bin/target-jsonl

The data by default will be written to a file called exchange_rate-{timestamp}.jsonl in your working directory.

› cat exchange_rate-{timestamp}.jsonl
{"CAD": 1.3954067515, "HKD": 7.7503228187, "ISK": 147.1130787678, "PHP": 50.5100534957, "DKK": 6.8779745434, "HUF": 327.9376498801, "CZK": 25.018446781, "GBP": 0.8059214167, "RON": 4.4673491976, "SEK": 9.9002029146, "IDR": 15321.0016602103, "INR": 75.6516325401, "BRL": 5.4711307877, "RUB": 73.6220254566, "HRK": 6.9765725881, "JPY": 106.548607268, "THB": 32.420217672, "CHF": 0.9750046117, "EUR": 0.9223390518, "MYR": 4.3475373547, "BGN": 1.8039107176, "TRY": 6.988286294, "CNY": 7.0764619074, "NOK": 10.3973436635, "NZD": 1.6446227633, "ZAR": 18.4316546763, "USD": 1.0, "MXN": 24.1217487548, "SGD": 1.4152370411, "AUD": 1.5361556908, "ILS": 3.5102379635, "KRW": 1218.9540675152, "PLN": 4.1912931194, "date": "2020-04-29T00:00:00Z"}

Optional Configuration

target-jsonl takes an optional configuration file that can be used to set formatting parameters like the delimiter - see config.sample.json for examples. To run target-jsonl with the configuration file, use this command:

~/.virtualenvs/tap-exchangeratesapi/bin/tap-exchangeratesapi | ~/.virtualenvs/target-jsonl/bin/target-jsonl -c my-config.json

Here is a brief description of the optional config keys

destination_path - Specifies where to write the resulting .jsonl file to. By default, the file gets written in your working directory.

custom_name - Specifies a custom name for the filename, instead of the stream name (i.e. {custom_name}-{timestamp}.jsonl, asumming do_timestamp_file is true). By default, the stream name will be used.

do_timestamp_file - specifies if the file should get timestamped. By default, the resulting file will have a timestamp in the file name (i.e. exchange_rate-{timestamp}.jsonl as described above in the Run section). If this option gets set to false, the resulting file will not have a timestamp associated with it (i.e. exchange_rate.jsonl in our example).

Copyright © 2020 Andy Huynh