embulk-input-http_json

An Embulk plugin to ingest json records from REST API with transformation by jq.

Overview

• Plugin type: input
• Resume supported: yes
• Cleanup supported: yes
• Guess supported: no

Configuration

• scheme: URI Scheme for the endpoint (string, default: "https", allows: "https", "http")
• host: Hostname or IP address of the endpoint (string, required)
• port: Port number of the endpoint (integer, optional, allows: 0-65535)
• path: Path of the endpoint (string, optional)
• headers: HTTP Headers (array of map, optional, allows: 1 element can contains 1 key-value.)
• method: HTTP Method (string, default: "GET", allows: "GET", "POST", "PUT", "PATCH", "DELETE", "GET", "HEAD", "OPTIONS", "TRACE", "CONNECT")
• params: HTTP Request params. This is merged with params for pagenation when the pager option is specified. (array of map, optional, allows: 1 element can contains 1 key-value.)
• body: HTTP Request body. (json, optional)
• success_condition: jq filter to check whether the response is succeeded or not. You can use jq to query for the status code and the response body. (string, ".status_code_class == 200")
• transformer: jq filter to transform the api response json. (string, "[.response_body]")
• extract_transformed_json_array: If true, the plugin extracts the transformed json array, and ingest them as records. (boolean, default: true)
• pager: (the following options are acceptable, default: {})
  • initial_params: Additional HTTP Request params that is used the first request. (array of map, optional, allows: 1 element can contains 1 key-value.)
  • next_params: Additional HTTP Request params that is used the subsequent requests. The value is treated as a jq filter to transform the prior response. (array of map, optional, allows: 1 element can contains 1 key-value.)
  • next_body_transformer: jq filter to transform the prior response to the next request body. (string, default: ".request_body")
  • while: jq filter to check whether the pagination is required or not. You can use jq to query for the status code and the response body. (string, "false")
  • interval_millis: Interval in milliseconds between requests. (integer, default: 100)
• retry: (the following options are acceptable, default: {})
  • condition: jq filter to check whether the response is retryable or not. This condition will be used when it is determined that the response is not succeeded by success_condition_jq. You can use jq to query for the status code and the response body. (string, "true")
  • max_retries: Maximum retries. (integer, default: 7)
  • initial_interval_millis: Initial retry interval in milliseconds. (integer, default: 1000)
  • max_interval_millis: Maximum retries interval in milliseconds. (integer, default: 60000)
• show_request_body_on_error: Show request body on error. (boolean, default: true)
• default_timezone: Default timezone. (string, default: "UTC")
• default_timestamp_format: Default timestamp format. (string, default: "%Y-%m-%d %H:%M:%S %z")
• default_date: Default date. (string, default: "1970-01-01")

About the jq filter

The following options accept the jq filter to transform the api response json.

• success_condition
• transformer
• pager/next_params
• pager/next_body_transformer
• retry/condition

All of the jq filters transform json that has the same format as the following.

{
  "request_params": [
    {"name": "foo", "value": "bar"}
  ],
  "request_body": {
    "foo": "bar"
  },
  "status_code": 201,
  "status_code_class": 200,
  "response_body": {
    "foo": "bar",
    "results": [
      {"id": 1, "name": "foo"},
      {"id": 2, "name": "bar"}
    ]
  }
}

The response of api is stored as the "response_body" field, so please note that the jq filter definition must start with .response_body in order to perform jq transformations on the API response results.

Example

in:
  type: http_json
  scheme: http
  host: localhost
  port: 8080
  path: /example
  method: GET
  transformer: '.response_body.integerValues'
  success_condition: '.status_code_class == 200'
out:
  type: stdout

Development

Run an example

Firstly, you need to start the mock server.

$ ./example/run-mock-server.sh

then, you run the example.

$ ./gradlew gem
$ embulk run -Ibuild/gemContents/lib -X min_output_tasks=1 example/config.yml

The requested records are shown on the mock server console.

Run tests

$ ./gradlew test

Build

$ ./gradlew gem  # -t to watch change of files and rebuild continuously

Update dependencies locks

$ ./gradlew dependencies --write-locks

Run the formatter

## Just check the format violations
$ ./gradlew spotlessCheck

## Fix the all format violations
$ ./gradlew spotlessApply

Release a new gem

A new tag is pushed, then a new gem will be released. See the Github Action CI Setting.

CHANGELOG

See. Github Releases

License

MIT LICENSE