This page explains features, concepts, and considerations to use when building your connected system plug-in.
Branding
Good logos and descriptions will help users find and use your plug-in.
- Add logos to your Connected System to show custom branding
- Add a description that tells us how to use your system. Why would I use it? What is exciting about it?
- For example, our Google Cloud Natural Language Connected System has the following description: Easily connect to Google Cloud Natural Language machine learning models. Extract structure and information from text, including both sentiment and key subjects such as people, places, and events. Integrations using this connected system will allow you to provide a text value and select which types of information to analyze.
- Check out Appian's Connected Systems for more examples.
Authentication
When authentication is required to send and receive information, fields can be configured to securely store credentials. Appian supports the use of the following authentication types for API requests:
- System username/password
- Basic authentication
- NTLM
- Digest
- Kerberos
- SOAP request body
- Prebuilt OAuth 2.0 (Authorization Code grant) - storage and retrieval of refresh and access tokens
- Custom - you can configure many different kinds of auth. Below are a few examples
Known Unsupported Authentication Mechanisms
Currently, you cannot build a plug-in that authenticates using:
- Anything Involving Certificate-Based Signing
- OAuth 2.0 (JWT Bearer Token)
- Per use credentials for anything other than OAuth 2.0 (e.g. Per-user creds for Basic auth)
- Secure storage of Short-lived token authentication
- OAuth 2.0 (Client Credentials)
- Workaround: You can configure your Connected System Template to request a token on each request. Be sure to review the policies and rate limits for the the service you are connecting to.
File Transfer
System Wide Configurations
Proxy Support
- If a proxy is enabled by an Appian administrator, you use the provided configuration data when making HTTP requests to non excluded hosts.
- See an example of using the proxy data to configure the Apache HttpClient
- Configuring HttpClient when a proxy is enabled
SSL
- Not supported. We do not currently provide trusted or client certificates.
Give Feedback on Errors
Diagnostics
Timing
Import Customizable Fields
Use Sensitive Values on Connected Systems
Connected System Plug-ins Restrictions
Connected Systems
- Must not implement both
TestableConnectedSystemTemplate
and OAuthConnectedSystemTemplate
- Fields must have a
RefreshPolicy
of NEVER
- Fields must not be expressionable
- Fields must not be
LIST
type
- Fields must not have deeply nested Local Types
- Don’t call setErrors(), as errors are ignored
Integrations
isImportCustomizable
should not be set to true
- Fields must not be encrypted
- Local Types must be expressionable
@TemplateId.majorVersion
annotation is ignored
Choices
- Each
Choice
must have a name
and value
PropertyDescriptors
- Fields that are
DisplayHint.EXPRESSION
must be expressionable
- Required fields must not be hidden
EncryptedTextPropertyDescriptors
isImportCustomizable
should be set to true
DocumentPropertyDescriptors
isImportCustomizable
should not be set to true
ListTypePropertyDescriptors
- Must be expressionable
- Must not have a placeholder
displayHint()
must be set to DisplayHint.Expression
LocalTypePropertyDescriptor
- Must not have a null type
isImportCustomizable
should not be set to true