Conversions

Jigx stores uploaded files as local files on the device and returns their file paths as local-uri. However, most REST APIs do not accept files in this format. To send files to a REST endpoint, you must convert the local-uri to a compatible format, such as base64, data-uri, or buffer, before including them in the request body.

Likewise, when retrieving files from a REST endpoint, they are often returned in a non-local format (e.g., base64 or buffer). To use or display these files in the app, you must convert them back to local-uri.

This is achieved by using conversions in functions. See File handling for detailed information on working with files and converting them into the correct format.

Example and code snippet

Incoming and outgoing conversions

In the examples below, the file conversions are configured:

1. In the REST (GET) functions to convert the incoming files to local-uri.

2. The file conversions are configured in the REST (SAVE/CREATE/UPDATE) functions to convert the files that are outgoing to REST.

rest-function-incoming

provider: DATA_PROVIDER_REST
method: GET
# Pdf indicates a generic binary type
format: pdf 
url: https://graph.microsoft.com/v1.0/me/photo/$value
outputTransform: $.{"data":$.data,"userId":$.inputs.userId.value} 
useLocalCall: true

parameters:
  accessToken:
    location: header
    required: true
    type: string
    value: oauth.microsoft 
  userId:
    type: string
    location: path
    required: true
# Add a conversion to ensure the file can be viewed in the app.    
conversions:
  - property: data
    from: base64
    to: local-uri

rest-function-outgoing

Convert device specific formats

In this example, the file conversion is configured in the REST function to convert the files that are outgoing via REST. convertHeicToJpg is configured to true to convert HEIC images to JPEG which ensures images are visible on iOS and Android devices.

YAML

provider: DATA_PROVIDER_REST
method: PATCH
url: https://graph.microsoft.com/v1.0/me/photo/$value
useLocalCall: true
parameters:
  accessToken:
    location: header
    required: true
    type: string
    # Use manage.jigx.com to define credentials for your solution
    value: oauth.microsoft 
  Content-Type:
    location: header
    required: true
    type: string
    # set the content type of the body
    value: image/jpeg 
  file:
    location: body
    required: true
    type: image
conversions:
  - property: file
    from: local-uri
    to: buffer
    convertHeicToJpg: true