plaid-OpenAPI

Help shape Plaid’s next-generation SDKs

We’re modernizing Plaid’s SDKs. The new Go library is available now as plaid-go v49, with the previous library included at github.com/plaid/plaid-go/v49/legacy. For the other languages, register your interest and we’ll follow up when an early release is available. No migration is required today.

Plaid uses the OpenAPI 3.0.0 specification to schematize our docs and to generate our supported client libraries. This provides for a consistent typing experience across our external interfaces. Below we have listed some examples and issues we have found when iterating on the specification.

Exact-discriminator oneOf support across the five SDKs

A named top-level component oneOf must use bare local branch references, an explicit one-to-one discriminator.mapping, and a required singleton discriminator enum on each direct object branch. Branches may be open or closed; additionalProperties controls model evolution independently of discriminator dispatch. Other named top-level oneOf shapes fail processing. Keep response branches and their nested objects open for additive compatibility; server-side request strictness is configured separately.

Language	Construct emitted	What you hold after decode
Go	struct wrapper	the wrapper — inspect its typed branch field or call GetActualInstance()
Java	interface	the branch — instanceof
Python	class(ModelComposed)	the branch — isinstance
Ruby	module	the branch — is_a?
Node	type alias	the branch — narrow on the discriminator

Go, Java, Python, and Ruby dispatch at runtime and reject missing or unknown discriminator values. Node provides compile-time narrowing only; axios returns parsed JSON without runtime discriminator validation.

Go is the only SDK that returns a wrapper. Its <Branch>As<Union>(...) helpers construct request wrappers; they are not decode accessors. Python also enforces required fields during deserialization while Go leaves missing fields at their zero values.

Using the OpenAPI generator

You can find examples on the official OpenApiGenerator docs.

Generating Plaid supported client libraries

The following are approximate commands that we use to generate our 5 client libraries:

plaid-node

OpenAPI Generator version: 5.1.1

openapi-generator-cli generate -g typescript-axios  \
-i 2020-09-14.yml \
-o build/generated-node \
-p npmName=plaid,supportsES6=true,modelPropertyNaming=original \
-t local/templates/typescript-axios

plaid-python

OpenAPI Generator version: 6.1

openapi-generator-cli generate -g python \
-i 2020-09-14.yml \
-o build/generated-python \
-p packageName=plaid \
--global-property apiTests=false,modelTests=false \
-t templates/python

plaid-ruby

OpenAPI Generator version: 6.3

openapi-generator-cli generate -g ruby  \
-i 2020-09-14.yml \
-o build/generated-ruby \
--global-property=apiTests=false,modelTests=false,useAutoload=true  \
--library=faraday \
-p gemName=plaid,gemRequiredRubyVersion=">= 3.2.0" \
-t local/templates/ruby

plaid-java

OpenAPI Generator version: 5.1.1

openapi-generator-cli generate -g java \
-i 2020-09-14.yml \
-o build/generated-java \
--library=retrofit2 \
--global-property apiDocs=false,modelDocs=false,apiTests=false,modelTests=false \
-p artifactId=plaid,apiPackage=com.plaid.client.request,modelPackage=com.plaid.client.model,dateLibrary=java8 \
-t templates/java \
--type-mappings=BigDecimal=Double

plaid-go

The command below generates the previous Go library, which plaid-go v49 includes as the legacy package.

OpenAPI Generator version: 5.2

openapi-generator-cli generate -g go \
-i 2020-09-14.yml \
-o build/plaid-go \
--global-property=apiTests=false,modelTests=false,apiDocs=false,modelDocs=false \
-t templates/go \
-p packageName=plaid,enumClassPrefix=true

Known issues with openapi-generator

The openapi-generator often uses different styles based on the language you are generating.

• We found that we had to modify our mustache templates to get servers and securitySchemes working for some generators. If possible, try not to modify these templates as they cause breaking changes upon upgrading, but modifications might be necessary for cases like these.

• Enums as used by Plaid are extensible; that is, the API may add new enum values at will. However, OpenAPI generator for some languages will enable enum validation by default. You must disable strict enum validation for responses in your generated libraries, or your users may experience crashes when encountering a newly-added enum value in a response.