degenerate 0.4.2

Generate typesafe Dart API clients from OpenAPI 3.x specs. Produces idiomatic models, serialization, and HTTP clients with pluggable adapters.

Changelog

Important user-facing changes only. For full details see commit log.

0.4.2

Bug fixes for enum parameter serialization, generated security helpers, and union parsing; anyOf + discriminator support.

Bug fixes

• Enum path parameters interpolate their wire value (#7): a path parameter whose schema is a $ref string enum produced debug strings like Color(red) in request URLs. Path interpolation now uses the enum's underlying value, and every other parameter serialization site (query, header, cookie, deepObject fields, list items, multipart text fields) was hardened so non-string enums and non-string-backed extension types no longer generate uncompilable code.
• apiKey schemes missing in or name no longer emit uncompilable code (#8): the generator defaults a missing name to the scheme key and a missing/invalid in to header (each with a CLI warning), and the with<Scheme> facade helper is only emitted when its matching apply<Scheme> method exists.
• Security requirement lists are explicitly typed (#9): operations opting out via security: [] emitted an untyped [] inferred as List<dynamic>; all requirement lists now carry an explicit <ApiSecurityRequirement> type argument.
• OneOf.parse falls through on Error, not just Exception (#10, thanks @josher8a): a variant's fromJson that discriminates by casting (e.g. json['x'] as String) throws a TypeError when the payload is a different variant; trial-parsing previously aborted instead of trying the next variant.
• Union variant names no longer collide with their referenced model: when the derived variant name <UnionName><PascalCase(value)> matches the referenced schema's own class name (e.g. OpenAI's Realtime events), the wrapper now uses a $ separator (RealtimeClientEvent$SessionUpdate), fixing ambiguous barrel exports and a self-recursive fromJson.

Improvements

• anyOf + discriminator generates sealed unions (#10, thanks @josher8a): schemas using anyOf with a discriminator (allowed by the OpenAPI spec) now lower to the same sealed-class hierarchy as oneOf when every variant is a $ref, instead of an untagged OneOfN. Affected schemas in regenerated clients change shape accordingly (e.g. OpenAI's ResponsesClientEvent).

0.4.1

Generated code is now lint-clean under very_good_analysis.

Breaking changes

• OneOf.parse callback signature: callback parameter type changed from Object? to Object (with json! assertion in runtime). Callers passing nullable values to parse callbacks will need to add a ! assertion.
• @immutable annotation: re-exported from degenerate_runtime. Generated model, enum, and union variant classes are now annotated @immutable.

Improvements

• Lint-clean generated output: generated Dart code now passes dart analyze with zero issues under very_good_analysis for all tested specs (Stripe, GitHub, Cloudflare, Twilio, etc.).
  • Constructors ordered before fields/methods (sort_constructors_first)
  • Required named parameters before optional (always_put_required_named_parameters_first)
  • Files end with exactly one trailing newline (eol_at_end_of_file)
  • Imports/exports sorted alphabetically (directives_ordering)
  • Security scheme literals omit redundant default values and use const (avoid_redundant_argument_values, prefer_const_constructors)
  • Raw strings and double-quoted strings used to avoid unnecessary escapes (use_raw_strings, avoid_escaping_inner_quotes)
  • Identity map transforms like .map((k, v) => MapEntry(k, v)) are elided (unnecessary_lambdas)
  • Simple closures like (e) => base64Encode(e) emit tearoffs (unnecessary_lambdas)
  • Empty model fromJson uses _ for unused parameter and const return (avoid_unused_constructor_parameters, prefer_const_constructors)
  • Doc comment [references] escaped to avoid false Dart doc links (comment_references)
  • Fenced code blocks in doc comments get a language specifier (missing_code_block_language_in_doc_comment)
  • Form-urlencoded body list literals are explicitly typed (inference_failure_on_collection_literal)
  • Untagged union fromJson casts accessor to Map<String, dynamic> for object variants (argument_type_not_assignable)
  • Extension type multipart serialization skips redundant .toString() when toJson() already returns String (noop_primitive_operations)

0.4.0

Critical fixes for discriminated unions, streaming, and runtime ergonomics.

Breaking changes

• OneOf types simplified: the sealed subclass hierarchy (OneOf2A, OneOf2B, etc.) is replaced by a single final class per arity. Code using is OneOf2A checks must switch to matching on .value type instead. Named constructors .a(), .b(), .c() etc. provide concise construction with Dart's implicit context syntax (e.g. model: .b(.gpt4oMini)).

Bug fixes

• Discriminator enum value extraction: inferred discriminator mappings now extract the actual enum value from referenced schemas (e.g. 'system' from role: enum: [system]) instead of using schema names. Fixes OpenAI ChatCompletionRequestMessage dispatch and similar patterns.
• Streaming interceptor bypass: executeStreaming and executeJsonlStreaming now run through the full interceptor chain (auth, retry, logging) before sending. Previously interceptors were completely bypassed for streaming requests, causing silent auth failures.
• Mid-stream error wrapping: network errors during SSE/JSONL streaming (SocketException, etc.) are now wrapped in ApiStreamError instead of propagating as raw platform exceptions.

Improvements

• OneOf variant deduplication: inline unions with duplicate variant types (e.g. OneOf3<A, A, B>) are collapsed to remove redundant variants (OneOf2<A, B>).
• Shorter discriminated union variant names: variant class names now use the discriminator enum value (ChatCompletionRequestMessageSystem) instead of the full schema name (ChatCompletionRequestMessageChatCompletionRequestSystemMessage).
• Added example.md with real-world usage patterns (OpenAI, streaming, Riverpod, envelope unwrapping).

0.3.0

Major feature release: allOf composition, additionalProperties, streaming, and OAS 3.2 support.

New features

• additionalProperties support: objects with additionalProperties now generate a typed overflow Map<String, T> field. Extra keys are preserved during fromJson/toJson round-trips instead of being silently dropped. Supports typed values, dynamic, and recursive self-references.
• allOf composition: allOf schemas that combine a $ref with extra inline properties now produce a merged object with all fields from both the ref target and the inline schema, instead of silently dropping the extra properties.
• --unwrap-fields CLI option: unwrap response envelopes by extracting a named field. --unwrap-fields=result returns the result type directly instead of the full {errors, messages, success, result} envelope — matching what Stainless generates for Cloudflare SDKs.
• OAS 3.2 query method: the HTTP QUERY method (safe method with request body) is now a first-class operation.
• OAS 3.2 additionalOperations: custom HTTP methods (COPY, LOCK, PURGE, etc.) via the path item's additionalOperations map.
• Typed streaming via itemSchema: SSE and JSONL responses with itemSchema now return Stream<T> with typed deserialization instead of void.
• JSONL streaming: application/jsonl and application/x-ndjson media types are now supported with a dedicated executeJsonlStreaming runtime method.
• Integer and number enums: enum schemas with type: integer or type: number now generate typed enums with int/double values, not just string enums.
• content-based parameter schemas: parameters using the OAS 3.x content field (instead of schema) now have their schema correctly extracted.
• OAuth2 deviceAuthorization: the device authorization flow type and deviceAuthorizationUrl are now supported.

Bug fixes

• String literal escaping: $, \n, \r, \t, and Unicode bidi/zero-width characters are now properly escaped in generated string literals.
• Object member name conflicts: fields and methods named toString, hashCode, runtimeType, or noSuchMethod are prefixed with $ to avoid conflicts with Object members.
• Discriminator mapping keys: inferred oneOf discriminator mappings now use the original schema names as switch keys, not the Dart type names.
• Discriminator toJson collision: union variant toJson spreads the variant first and sets the discriminator key last, so the discriminator always wins over fields with the same name.
• type: "null" handling: type: "null" now maps to nullable dynamic instead of String.
• canParse for optional-only models: models with no required fields now check for at least one known property key instead of returning true unconditionally.
• Latin character transliteration: accented characters are transliterated to ASCII (café → cafe) instead of being stripped (caf).
• Enum casing: leading +/- before letters in enum values no longer corrupts casing (+NaN → naN, not NaN).
• Query/header parameter key escaping: $ and special characters in parameter names are properly escaped in generated map key strings.

0.2.1

• Fix required-but-nullable query parameters generating invalid assignments (String? assigned to Map<String, String>)
• Add totem-web.json to snapshot testing

0.2.0

Breaking changes to CLI defaults and output structure.

• New default output: generated code goes to lib/<name>/ (was lib/src/generated/). The -n flag sets the package name (default: api_client) and is appended to the -o base directory.
• Workspace mode (--workspace): generates a standalone Dart package with pubspec.yaml to packages/<name>/ (customizable with -o). Includes resolution: workspace for Dart workspaces.
• Flattened directory structure: removed the src/ directory from generated output. Models, APIs, client, and barrel file are now siblings (e.g. models/, apis/, client/, <name>.dart). Workspace mode wraps these under lib/.
• No pubspec in default mode: the CLI prints the dependencies you need to add to your own pubspec.yaml after generation.
• Post-generation instructions: the CLI now prints setup instructions (dependencies for default mode, workspace + dependency config for workspace mode).
• Unformatted output: generated code is no longer annotated with // dart format off. Run dart format on the output to apply your project's formatting preferences.
• Dropped collection dependency: replaced ListEquality with a built-in listEquals in degenerate_runtime. One fewer dependency for generated code.
• Simplified file headers: generated files now contain only // GENERATED CODE - DO NOT MODIFY BY HAND.

0.1.5

• Fix published package containing workspace field in pubspec.yaml, which caused dart run build_runner failures for users

0.1.4

• Add stdin pipe support (-i -): generate from curl, cat, or any command (e.g. curl https://example.com/spec.json | degenerate -i - -o lib/src/api -n my_api)

0.1.3

• Fix runtime crash for required+nullable fields in fromJson (type 'Null' is not a subtype of type 'String' in type cast)
• Fix enum values with special characters (e.g. [DONE]) generating PascalCase instead of lowerCamelCase

0.1.2

• Add GitHub Actions CI
• Add release script (make release)
• Make runtime packages publishable to pub.dev (version constraints instead of path deps)

0.1.1

• Fix README image on pub.dev
• Add GitHub Actions CI
• Add release script (make release)
• Make runtime packages publishable to pub.dev (version constraints instead of path deps)

0.1.0

• Initial version.