API-Builder File Flow-Node

This node can be used to read and write files in your API-Builder flow.

The following file types are supported/planned:

| File Type | Description | Status | | ----------- | ----------- | ------ | |CSV |You can read/write from and to CSV-Files, filter records and columns and directly convert it into a JavaScript object |Support for Read| |JSON |You can read/write from and to JSON-Files and directly convert it into a JavaScript object |Planned| |XML |You can read/write from and to XML-Files and directly convert it into a JavaScript object |Planned| |Plain-Text|Just read and write plain text|Planned|

CSV Files

With this flow-node you can read CSV-File and make the content available to your flow. With that, you can for instance enrich data taken from the CSV-File and merge it with data you got before.

Read

To Read a CSV-File, you have to make it available to the API-Builder project. For instance putting it directly into your API-Builder app and reference it then with a relative path.

Input parameters

The CSV Read-Operation supports a number of input parameters:

| Param | Type | Required | Description | | ----------- | ----------- | -------- | ----------- | | filename | string | y | The name of the CSV file you would like to read. This file is given either absolute or relative to the API-Builder project. For instance, when putting a file into conf/my-file.csv you just configured conf/my-file.csv | | delimiter | string | n | The delimeter of your CSV-File. Defaults to , Configure any other character, when your CSV-File is splitting records differently.| | filterColumn | string | n | The CSV column name used to filter using the filterValues. This parameter is ignored, if filterValues is not set. | | filterValues | string|array | n | This value is used to filter entries in the configured filterColumn. It can be either a simple string or an array of string. The parameter is case-sensitve. This parameter is ignored, if filterColumn is not set. | | uniqueResult | boolean | n | Turn this on if you require a unique result (exactly 1). If not unique or nothing is found the flow node fails. | | resultColumns | array | n | An array of CSV column names you want in the result. The column names are expected in the first line or using the parameter: columnsyou can override the column names. Example: ["columnA", "columnF", "columnT"] | | quote | string | n | Optional character surrounding a field. This is required, when the delimiter is used as part of a field; one character only. The default is double quote. | | comment | string | n | Treat all the characters after this one as a comment. Used this, when your CSV-File contains lines with comments. E.g. using a # | | columns | array | n | Provide an array of column headers if your CSV has NO headers or you would like to have different field names. | | relax_column_count| boolean | n | Discard inconsistent columns count. If a column is missing for a record a reduced dataset is returned. |

Output

The content from the CSV-File is converted into a Java-Script object, so that you can easily use it in your flow.

For instance the following input:

ReturnCode, ResponseMessage, LastUpdate, Author
401, You have no permission, 16.01.2020, Chris
500, Internal server error, 17.01.2020, Charles

is made available to the flow as the following object:

{
  ReturnCode: '401',
  ResponseMessage: 'You have no permission',
  LastUpdate: '16.01.2020',
  Author: 'Chris'
},
{
  ReturnCode: '500',
  ResponseMessage: 'Internal server error',
  LastUpdate: '17.01.2020',
  Author: 'Charles'
}

When using the default output attribute: $.content you can access the data inside your flow like so: $.content.1.ReturnCode to get the second return-code.

Using the parameters: filterColumn, filterValues and uniqueResult you can limit the data to one record. In that case, the data is always stored in the first object: $.content.0.ReturnCode

Write

This is not yet supported. Please create an issue describing your use-case, if you need support for it.

JSON Files

Read

This is not yet supported. Please create an issue describing your use-case, if you need support for it.

Write

This is not yet supported. Please create an issue describing your use-case, if you need support for it.

XML Files

Read

This is not yet supported. Please create an issue describing your use-case, if you need support for it.

Write

This is not yet supported. Please create an issue describing your use-case, if you need support for it.

Plain Text

Read

This is not yet supported. Please create an issue describing your use-case, if you need support for it.

Write

The intention of this operation is to write the content of an attribute into a on your API-Builder project. As an API-Builder project is supposed to run in a docker container and the nature of it, the location should be an external share.

Input parameters

The Write-Operation supports a number of input parameters:

| Param | Type | Required | Description | | ----------- | ----------- | -------- | ----------- | | filename | string | y | The name of the file you would like to write. This filename is given either absolute or relative to the API-Builder project. For instance, when using a filename like conf/output.txt the file is written in the conf folder within you API-Builder project.| | data | string | Y | This is parameter contains the data to write to the filter. You can either use a hard-coded string, but very likely you use a selector to reference for instance the received content body| | overwrite | boolean | n | Set this optional toggle to true, if you would like to overwrite already existing files. | | dataEncoding | string | n | Optionally, set the data encoding, which is used to write the file. If not set UTF-8 is used. | | stringify | boolean | n | By default, if data is an Object, it is automatially stringified (JSON.stringify). Using this option you can turn off that feature.|

Output

Next

Is followed when the file has been successfully writen. The variable contains the filename of file.

Error

An error has occured and you get back the error message.

After creating your API Builder service (api-builder init), you can install this plugin using npm:

npm install api-builder-plugin-fn-file

Changelog

See Change-Log