diff --git a/.all-contributorsrc b/.all-contributorsrc index 48635c73..84ece03b 100644 --- a/.all-contributorsrc +++ b/.all-contributorsrc @@ -483,6 +483,18 @@ "contributions": [ "doc" ] + }, + { + "login": "Pakisan", + "name": "Pavel Bodiachevskii", + "avatar_url": "https://avatars.githubusercontent.com/u/3388414?v=4", + "profile": "https://www.linkedin.com/in/pavel-bo/", + "contributions": [ + "doc", + "bug", + "ideas", + "question" + ] } ], "commitConvention": "none", diff --git a/README.md b/README.md index 30160a14..f965564c 100644 --- a/README.md +++ b/README.md @@ -207,6 +207,7 @@ Thanks goes to these wonderful people ([emoji key](https://allcontributors.org/d Ace
Ace
📋 🤔 🚧 📢 Animesh Kumar
Animesh Kumar
🖋 📖 🚧 Fabrizio Lazzaretti
Fabrizio Lazzaretti
📖 + Pavel Bodiachevskii
Pavel Bodiachevskii
📖 🐛 🤔 💬 diff --git a/spec/asyncapi.md b/spec/asyncapi.md index bd7bada5..b8532abb 100644 --- a/spec/asyncapi.md +++ b/spec/asyncapi.md @@ -1,10 +1,10 @@ # AsyncAPI Specification -#### Attribution +## Attribution Part of this content has been taken from the great work done by the folks at the [OpenAPI Initiative](https://openapis.org). -#### Version 3.0.0 +### Version 3.0.0 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC 2119](https://www.ietf.org/rfc/rfc2119.txt). @@ -116,35 +116,43 @@ Aside from the issues mentioned above, there may also be infrastructure configur -## Definitions +## Definitions + +### Server -### Server A server MAY be a message broker that is capable of sending and/or receiving between a [sender](#definitionsSender) and [receiver](#definitionsReceiver). A server MAY be a service with WebSocket API that enables message-driven communication between browser-to-server or server-to-server. -### Application -An application is any kind of computer program or a group of them. It MUST be a [sender](#definitionsSender), a [receiver](#definitionsReceiver), or both. An application MAY be a microservice, IoT device (sensor), mainframe process, message broker, etc. An application MAY be written in any number of different programming languages as long as they support the selected [protocol](#definitionsProtocol). An application MUST also use a protocol supported by the [server](#definitionsServer) in order to connect and exchange [messages](#definitionsMessage). +### Application + +An application is any kind of computer program or a group of them. It MUST be a [sender](#definitionsSender), a [receiver](#definitionsReceiver), or both. An application MAY be a microservice, IoT device (sensor), mainframe process, message broker, etc. An application MAY be written in any number of different programming languages as long as they support the selected [protocol](#definitionsProtocol). An application MUST also use a protocol supported by the [server](#definitionsServer) in order to connect and exchange [messages](#definitionsMessage). + +### Sender -### Sender A sender is a type of application, that is sending [messages](#definitionsMessage) to [channels](#definitionsChannel). A sender MAY send to multiple channels depending on the [server](#definitionsServer), protocol, and use-case pattern. -### Receiver +### Receiver + A receiver is a type of application that is receiving [messages](#definitionsMessage) from [channels](#definitionsChannel). A receiver MAY receive from multiple channels depending on the [server](#definitionsServer), protocol, and the use-case pattern. A receiver MAY forward a received message further without changing it. A receiver MAY act as a consumer and react to the message. A receiver MAY act as a processor that, for example, aggregates multiple messages in one and forwards them. -### Message -A message is the mechanism by which information is exchanged via a channel between [servers](#definitionsServer) and applications. A message MAY contain a payload and MAY also contain headers. The headers MAY be subdivided into [protocol](#definitionsProtocol)-defined headers and header properties defined by the application which can act as supporting metadata. The payload contains the data, defined by the application, which MUST be serialized into a format (JSON, XML, Avro, binary, etc.). Since a message is a generic mechanism, it can support multiple interaction patterns such as event, command, request, or response. +### Message + +A message is the mechanism by which information is exchanged via a channel between [servers](#definitionsServer) and applications. A message MAY contain a payload and MAY also contain headers. The headers MAY be subdivided into [protocol](#definitionsProtocol)-defined headers and header properties defined by the application which can act as supporting metadata. The payload contains the data, defined by the application, which MUST be serialized into a format (JSON, XML, Avro, binary, etc.). Since a message is a generic mechanism, it can support multiple interaction patterns such as event, command, request, or response. + +### Channel -### Channel A channel is an addressable component, made available by the [server](#definitionsServer), for the organization of [messages](#definitionsMessage). [Sender](#definitionsSender) applications send messages to channels and [receiver](#definitionsReceiver) applications receive messages from channels. [Servers](#definitionsServer) MAY support many channel instances, allowing messages with different content to be addressed to different channels. Depending on the [server](#definitionsServer) implementation, the channel MAY be included in the message via protocol-defined headers. -### Protocol +### Protocol + A protocol is the mechanism (wireline protocol or API) by which [messages](#definitionsMessage) are exchanged between the application and the [channel](#definitionsChannel). Example protocols include, but are not limited to, AMQP, HTTP, JMS, Kafka, Anypoint MQ, MQTT, Solace, STOMP, Mercure, WebSocket, Google Pub/Sub, Pulsar. -### Bindings -A "binding" (or "protocol binding") is a mechanism to define protocol-specific information. Therefore, a protocol binding MUST define protocol-specific information only. +### Bindings + +A "binding" (or "protocol binding") is a mechanism to define protocol-specific information. Therefore, a protocol binding MUST define protocol-specific information only. -## Specification +## Specification -### Format +### Format The files describing the message-driven API in accordance with the AsyncAPI Specification are represented as JSON objects and conform to the JSON standards. YAML, being a superset of JSON, can be used as well to represent a A2S (AsyncAPI Specification) file. @@ -170,7 +178,7 @@ In order to preserve the ability to round-trip between YAML and JSON formats, YA - Tags MUST be limited to those allowed by the [JSON Schema ruleset](https://www.yaml.org/spec/1.2/spec.html#id2803231) - Keys used in YAML maps MUST be limited to a scalar string, as defined by the YAML Failsafe schema ruleset -### File Structure +### File Structure An AsyncAPI document MAY be made up of a single document or be divided into multiple, connected parts at the discretion of the author. In the latter case, [Reference Objects](#referenceObject) are used. @@ -179,13 +187,13 @@ It is important to note that everything that is defined in an AsyncAPI document By convention, the AsyncAPI Specification (A2S) file is named `asyncapi.json` or `asyncapi.yaml`. -### Absolute URLs +### Absolute URLs Unless specified otherwise, all properties that are absolute URLs are defined by [RFC3986, section 4.3](https://datatracker.ietf.org/doc/html/rfc3986#section-4.3). -### Schema +### Schema -#### AsyncAPI Object +#### AsyncAPI Object This is the root document object for the API specification. It combines resource listing and API declaration together into one document. @@ -205,7 +213,7 @@ Field Name | Type | Description This object MAY be extended with [Specification Extensions](#specificationExtensions). -#### AsyncAPI Version String +#### AsyncAPI Version String The version string signifies the version of the AsyncAPI Specification that the document complies to. The format for this string _must_ be `major`.`minor`.`patch`. The `patch` _may_ be suffixed by a hyphen and extra alphanumeric characters. @@ -215,13 +223,13 @@ The patch version will not be considered by tooling, making no distinction betwe In subsequent versions of the AsyncAPI Specification, care will be given such that increments of the `minor` version should not interfere with operations of tooling developed to a lower minor version. Thus a hypothetical `1.1.0` specification should be usable with tooling designed for `1.0.0`. -#### Identifier +#### Identifier This field represents a unique universal identifier of the [application](#definitionsApplication) the AsyncAPI document is defining. It must conform to the URI format, according to [RFC3986](https://tools.ietf.org/html/rfc3986). It is RECOMMENDED to use a [URN](https://tools.ietf.org/html/rfc8141) to globally and uniquely identify the application during long periods of time, even after it becomes unavailable or ceases to exist. -###### Examples +##### Examples ```json { @@ -243,7 +251,7 @@ id: 'urn:example:com:smartylighting:streetlights:server' id: 'https://github.com/smartylighting/streetlights-server' ``` -#### Info Object +#### Info Object The object provides metadata about the API. The metadata can be used by the clients if needed. @@ -263,7 +271,7 @@ Field Name | Type | Description This object MAY be extended with [Specification Extensions](#specificationExtensions). -##### Info Object Example: +##### Info Object Example ```json { @@ -311,7 +319,7 @@ tags: - name: e-commerce ``` -#### Contact Object +#### Contact Object Contact information for the exposed API. @@ -325,7 +333,7 @@ Field Name | Type | Description This object MAY be extended with [Specification Extensions](#specificationExtensions). -##### Contact Object Example: +##### Contact Object Example ```json { @@ -341,7 +349,7 @@ url: https://www.example.com/support email: support@example.com ``` -#### License Object +#### License Object License information for the exposed API. @@ -354,7 +362,7 @@ Field Name | Type | Description This object MAY be extended with [Specification Extensions](#specificationExtensions). -##### License Object Example: +##### License Object Example ```json { @@ -368,7 +376,7 @@ name: Apache 2.0 url: https://www.apache.org/licenses/LICENSE-2.0.html ``` -#### Servers Object +#### Servers Object The Servers Object is a map of [Server Objects](#serverObject). @@ -448,8 +456,7 @@ production: description: "This environment is the live environment available for final users." ``` - -#### Server Object +#### Server Object An object representing a message broker, a server or any other kind of computer program capable of sending and/or receiving data. This object is used to capture details such as URIs, protocols and security configuration. Variable substitution can be used so that some details, for example usernames and passwords, can be injected by code generation tools. @@ -508,7 +515,7 @@ protocol: amqp description: Production RabbitMQ broker (uses the `production` vhost). ``` -#### Server Variable Object +#### Server Variable Object An object representing a Server Variable for server URL template substitution. @@ -556,8 +563,7 @@ variables: - staging ``` - -#### Default Content Type +#### Default Content Type A string representing the default content type to use when encoding/decoding a message's payload. The value MUST be a specific media type (e.g. `application/json`). This value MUST be used by schema parsers when the [contentType](#messageObjectContentType) property is omitted. @@ -575,12 +581,7 @@ In case a message can't be encoded/decoded using this value, schema parsers MUST defaultContentType: application/json ``` - - - - - -#### Channels Object +#### Channels Object An object containing all the [Channel Object](#channelObject) definitions the [Application](#definitionsApplication) MUST use during runtime. @@ -613,10 +614,7 @@ userSignedUp: $ref: '#/components/messages/userSignedUp' ``` - - - -#### Channel Object +#### Channel Object Describes a shared communication channel. @@ -635,7 +633,6 @@ Field Name | Type | Description externalDocs | [External Documentation Object](#externalDocumentationObject) \| [Reference Object](#referenceObject) | Additional external documentation for this channel. bindings | [Channel Bindings Object](#channelBindingsObject) \| [Reference Object](#referenceObject) | A map where the keys describe the name of the protocol and the values describe protocol-specific definitions for the channel. - This object MAY be extended with [Specification Extensions](#specificationExtensions). ##### Channel Object Example @@ -709,21 +706,13 @@ externalDocs: url: 'https://example.com' ``` - - - - -#### Channel Address Expressions +#### Channel Address Expressions Channel addresses MAY contain expressions that can be used to define dynamic values. Expressions MUST be composed by a name enclosed in curly braces (`{` and `}`). E.g., `{userId}`. - - - - -#### Messages Object +#### Messages Object Describes a map of messages included in a channel. @@ -753,9 +742,7 @@ userCompletedOrder: $ref: '#/components/messages/userCompletedOrder' ``` - - -#### Operations Object +#### Operations Object Holds a dictionary with all the [operations](#operationObject) this application MUST implement. @@ -815,8 +802,7 @@ onUserSignUp: - $ref: '#/components/operationTraits/kafka' ``` - -#### Operation Object +#### Operation Object Describes a specific operation. @@ -919,10 +905,7 @@ reply: - $ref: '#/components/messages/userSignedUpReply' ``` - - - -#### Operation Trait Object +#### Operation Trait Object Describes a trait that MAY be applied to an [Operation Object](#operationObject). This object MAY contain any property from the [Operation Object](#operationObject), except the `action`, `channel`, `messages` and `traits` ones. @@ -960,10 +943,7 @@ bindings: ack: false ``` - - - -#### Operation Reply Object +#### Operation Reply Object Describes the reply part that MAY be applied to an Operation Object. If an operation implements the request/reply pattern, the reply object represents the response message. @@ -977,13 +957,12 @@ Field Name | Type | Description This object MAY be extended with [Specification Extensions](#specificationExtensions). -#### Operation Reply Address Object +#### Operation Reply Address Object -An object that specifies where an operation has to send the reply. +An object that specifies where an operation has to send the reply. For specifying and computing the location of a reply address, a [runtime expression](#runtimeExpression) is used. - ##### Fixed Fields Field Name | Type | Description @@ -1007,8 +986,7 @@ description: Consumer Inbox location: $message.header#/replyTo ``` - -#### Parameters Object +#### Parameters Object Describes a map of parameters included in a channel address. @@ -1040,11 +1018,7 @@ parameters: description: Id of the user. ``` - - - - -#### Parameter Object +#### Parameter Object Describes a parameter included in a channel address. @@ -1082,10 +1056,7 @@ parameters: location: $message.payload#/user/id ``` - - - -#### Server Bindings Object +#### Server Bindings Object Map describing protocol-specific definitions for a server. @@ -1115,9 +1086,7 @@ Field Name | Type | Description This object MAY be extended with [Specification Extensions](#specificationExtensions). - - -#### Channel Bindings Object +#### Channel Bindings Object Map describing protocol-specific definitions for a channel. @@ -1147,9 +1116,7 @@ Field Name | Type | Description This object MAY be extended with [Specification Extensions](#specificationExtensions). - - -#### Operation Bindings Object +#### Operation Bindings Object Map describing protocol-specific definitions for an operation. @@ -1179,10 +1146,7 @@ Field Name | Type | Description This object MAY be extended with [Specification Extensions](#specificationExtensions). - - - -#### Message Bindings Object +#### Message Bindings Object Map describing protocol-specific definitions for a message. @@ -1212,13 +1176,7 @@ Field Name | Type | Description This object MAY be extended with [Specification Extensions](#specificationExtensions). - - - - - - -#### Message Object +#### Message Object Describes a message received on a given channel and operation. @@ -1227,7 +1185,7 @@ Describes a message received on a given channel and operation. Field Name | Type | Description ---|:---:|--- headers | [Multi Format Schema Object](#multiFormatSchemaObject) | [Schema Object](#schemaObject) | [Reference Object](#referenceObject) | Schema definition of the application headers. Schema MUST be a map of key-value pairs. It **MUST NOT** define the protocol headers. If this is a [Schema Object](#schemaObject), then the `schemaFormat` will be assumed to be "application/vnd.aai.asyncapi+json;version=`asyncapi`" where the version is equal to the [AsyncAPI Version String](#A2SVersionString). -payload | [Multi Format Schema Object](#multiFormatSchemaObject) | [Schema Object](#schemaObject) | [Reference Object](#referenceObject) | Definition of the message payload. If this is a [Schema Object](#schemaObject), then the `schemaFormat` will be assumed to be "application/vnd.aai.asyncapi+json;version=`asyncapi`" where the version is equal to the [AsyncAPI Version String](#A2SVersionString). +payload | [Multi Format Schema Object](#multiFormatSchemaObject) | [Schema Object](#schemaObject) | [Reference Object](#referenceObject) | Definition of the message payload. If this is a [Schema Object](#schemaObject), then the `schemaFormat` will be assumed to be "application/vnd.aai.asyncapi+json;version=`asyncapi`" where the version is equal to the [AsyncAPI Version String](#A2SVersionString). correlationId | [Correlation ID Object](#correlationIdObject) | [Reference Object](#referenceObject) | Definition of the correlation ID used for message tracing or matching. contentType | `string` | The content type to use when encoding/decoding a message's payload. The value MUST be a specific media type (e.g. `application/json`). When omitted, the value MUST be the one specified on the [defaultContentType](#defaultContentTypeString) field. name | `string` | A machine-friendly name for the message. @@ -1389,13 +1347,7 @@ payload: $ref: 'path/to/user-create.avsc/#UserCreate' ``` - - - - - - -#### Message Trait Object +#### Message Trait Object Describes a trait that MAY be applied to a [Message Object](#messageObject). This object MAY contain any property from the [Message Object](#messageObject), except `payload` and `traits`. @@ -1431,15 +1383,15 @@ This object MAY be extended with [Specification Extensions](#specificationExtens contentType: application/json ``` -#### Message Example Object +#### Message Example Object -Message Example Object represents an example of a [Message Object](#messageObject) and MUST contain either **headers** and/or **payload** fields. +Message Example Object represents an example of a [Message Object](#messageObject) and MUST contain either **headers** and/or **payload** fields. ##### Fixed Fields Field Name | Type | Description ---|:---:|--- -headers | `Map[string, any]` | The value of this field MUST validate against the [Message Object's headers](#messageObjectHeaders) field. +headers | `Map[string, any]` | The value of this field MUST validate against the [Message Object's headers](#messageObjectHeaders) field. payload | `Map[string, any]` | The value of this field MUST validate against the [Message Object's payload](#messageObjectPayload) field. name | `string` | A machine-friendly name. summary | `string` | A short summary of what the example is about. @@ -1480,15 +1432,16 @@ payload: someSignupKey: someSignupValue ``` -#### Tags Object +#### Tags Object A Tags object is a list of [Tag Objects](#tagObject). An [Tag Object](#tagObject) in a list can be referenced by [Reference Object](#referenceObject). -#### Tag Object +#### Tag Object Allows adding meta data to a single tag. ##### Fixed Fields + Field Name | Type | Description ---|:---:|--- name | `string` | **REQUIRED.** The name of the tag. @@ -1501,8 +1454,8 @@ This object MAY be extended with [Specification Extensions](#specificationExtens ```json { - "name": "user", - "description": "User-related messages" + "name": "user", + "description": "User-related messages" } ``` @@ -1511,13 +1464,7 @@ name: user description: User-related messages ``` - - - - - - -#### External Documentation Object +#### External Documentation Object Allows referencing an external resource for extended documentation. @@ -1544,8 +1491,7 @@ description: Find more info here url: https://example.com ``` - -#### Reference Object +#### Reference Object A simple object to allow referencing other components in the specification, internally and externally. @@ -1554,6 +1500,7 @@ The Reference Object is defined by [JSON Reference](https://tools.ietf.org/html/ For this specification, reference resolution is done as defined by the JSON Reference specification and not by the JSON Schema specification. ##### Fixed Fields + Field Name | Type | Description ---|:---:|--- $ref | `string` | **REQUIRED.** The reference string. @@ -1572,7 +1519,7 @@ This object cannot be extended with additional properties and any properties add $ref: '#/components/schemas/Pet' ``` -#### Components Object +#### Components Object Holds a set of reusable objects for different aspects of the AsyncAPI specification. All objects defined within the components object will have no effect on the API unless they are explicitly referenced from properties outside the components object. @@ -1580,14 +1527,14 @@ All objects defined within the components object will have no effect on the API ##### Fixed Fields Field Name | Type | Description ----|:---|--- +---|:---|--- schemas | Map[`string`, [Multi Format Schema Object](#multiFormatSchemaObject) \| [Schema Object](#schemaObject) \| [Reference Object](#referenceObject)] | An object to hold reusable [Schema Object](#schemaObject). If this is a [Schema Object](#schemaObject), then the `schemaFormat` will be assumed to be "application/vnd.aai.asyncapi+json;version=`asyncapi`" where the version is equal to the [AsyncAPI Version String](#A2SVersionString). servers | Map[`string`, [Server Object](#serverObject) \| [Reference Object](#referenceObject)] | An object to hold reusable [Server Objects](#serverObject). channels | Map[`string`, [Channel Object](#channelObject) \| [Reference Object](#referenceObject)] | An object to hold reusable [Channel Objects](#channelObject). operations | Map[`string`, [Operation Object](#operationObject) \| [Reference Object](#referenceObject)] | An object to hold reusable [Operation Objects](#operationObject). messages | Map[`string`, [Message Object](#messageObject) \| [Reference Object](#referenceObject)] | An object to hold reusable [Message Objects](#messageObject). securitySchemes| Map[`string`, [Security Scheme Object](#securitySchemeObject) \| [Reference Object](#referenceObject)] | An object to hold reusable [Security Scheme Objects](#securitySchemeObject). - serverVariables | Map[`string`, [Server Variable Object](#serverVariableObject) \| [Reference Object](#referenceObject)] | An object to hold reusable [Server Variable Objects](#serverVariableObject). + serverVariables | Map[`string`, [Server Variable Object](#serverVariableObject) \| [Reference Object](#referenceObject)] | An object to hold reusable [Server Variable Objects](#serverVariableObject). parameters | Map[`string`, [Parameter Object](#parameterObject) \| [Reference Object](#referenceObject)] | An object to hold reusable [Parameter Objects](#parameterObject). correlationIds | Map[`string`, [Correlation ID Object](#correlationIdObject) \| [Reference Object](#referenceObject)] | An object to hold reusable [Correlation ID Objects](#correlationIdObject). replies | Map[`string`, [Operation Reply Object](#operationReplyObject) \| [Reference Object](#referenceObject)] | An object to hold reusable [Operation Reply Objects](#operationReplyObject). @@ -1607,7 +1554,7 @@ All the fixed fields declared above are objects that MUST use keys that match th Field Name Examples: -``` +```text User User_1 User_Name @@ -1836,7 +1783,7 @@ components: maximum: 100 ``` -#### Multi Format Schema Object +#### Multi Format Schema Object The Multi Format Schema Object represents a schema definition. It differs from the [Schema Object](#schemaObject) in that it supports multiple schema formats or languages (e.g., JSON Schema, Avro, etc.). @@ -1849,26 +1796,48 @@ Field Name | Type | Description This object MAY be extended with [Specification Extensions](#specificationExtensions). -##### Schema formats table +##### Schema formats table The following table contains a set of values that every implementation MUST support. Name | Allowed values | Notes ---|:---:|--- [AsyncAPI 3.0.0 Schema Object](#schemaObject) | `application/vnd.aai.asyncapi;version=3.0.0`, `application/vnd.aai.asyncapi+json;version=3.0.0`, `application/vnd.aai.asyncapi+yaml;version=3.0.0` | This is the default when a `schemaFormat` is not provided. -[JSON Schema Draft 07](https://json-schema.org/specification-links.html#draft-7) | `application/schema+json;version=draft-07`, `application/schema+yaml;version=draft-07` | +[JSON Schema Draft 07](https://json-schema.org/specification-links.html#draft-7) | `application/schema+json;version=draft-07`, `application/schema+yaml;version=draft-07` | The following table contains a set of values that every implementation is RECOMMENDED to support. Name | Allowed values | Notes ---|:---:|--- [Avro 1.9.0 schema](https://avro.apache.org/docs/1.9.0/spec.html#schemas) | `application/vnd.apache.avro;version=1.9.0`, `application/vnd.apache.avro+json;version=1.9.0`, `application/vnd.apache.avro+yaml;version=1.9.0` | -[OpenAPI 3.0.0 Schema Object](https://github.com/OAI/OpenAPI-Specification/blob/master/versions/3.0.0.md#schemaObject) | `application/vnd.oai.openapi;version=3.0.0`, `application/vnd.oai.openapi+json;version=3.0.0`, `application/vnd.oai.openapi+yaml;version=3.0.0` | +[OpenAPI 3.0.0 Schema Object](https://github.com/OAI/OpenAPI-Specification/blob/master/versions/3.0.0.md#schemaObject) | `application/vnd.oai.openapi;version=3.0.0`, `application/vnd.oai.openapi+json;version=3.0.0`, `application/vnd.oai.openapi+yaml;version=3.0.0` | [RAML 1.0 data type](https://github.com/raml-org/raml-spec/blob/master/versions/raml-10/raml-10.md/) | `application/raml+yaml;version=1.0` | -[Protocol Buffers](https://protobuf.dev/) | `application/vnd.google.protobuf;version=2`, `application/vnd.google.protobuf;version=3` | +[Protocol Buffers](https://protobuf.dev/) | `application/vnd.google.protobuf;version=2`, `application/vnd.google.protobuf;version=3` | + +##### Multi Format Schema Object Examples +###### Multi Format Schema Object Example with Avro -#### Schema Object +```yaml +channels: + example: + messages: + myMessage: + payload: + schemaFormat: 'application/vnd.apache.avro;version=1.9.0' + schema: + type: record + name: User + namespace: com.company + doc: User information + fields: + - name: displayName + type: string + - name: age + type: int +``` + +#### Schema Object The Schema Object allows the definition of input and output data types. These types can be objects, but also primitives and arrays. This object is a superset of the [JSON Schema Specification Draft 07](https://json-schema.org/). The empty schema (which allows any instance to validate) MAY be represented by the `boolean` value `true` and a schema which allows no instance to validate MAY be represented by the `boolean` value `false`. @@ -1925,6 +1894,7 @@ Alternatively, any time a Schema Object can be used, a [Reference Object](#refer In addition to the JSON Schema fields, the following AsyncAPI vocabulary fields MAY be used for further schema documentation: ##### Fixed Fields + Field Name | Type | Description ---|:---:|--- discriminator | `string` | Adds support for polymorphism. The discriminator is the schema property name that is used to differentiate between other schema that inherit this schema. The property name used MUST be defined at this schema and it MUST be in the `required` property list. When used, the value MUST be the name of this schema or any schema that inherits it. See [Composition and Inheritance](#schemaComposition) for more details. @@ -1933,10 +1903,10 @@ Field Name | Type | Description This object MAY be extended with [Specification Extensions](#specificationExtensions). -###### Composition and Inheritance (Polymorphism) +###### Composition and Inheritance (Polymorphism) The AsyncAPI Specification allows combining and extending model definitions using the `allOf` property of JSON Schema, in effect offering model composition. -`allOf` takes in an array of object definitions that are validated *independently* but together compose a single object. +`allOf` takes in an array of object definitions that are validated _independently_ but together compose a single object. While composition offers model extensibility, it does not imply a hierarchy between the models. To support polymorphism, AsyncAPI Specification adds the support of the `discriminator` field. @@ -1947,7 +1917,7 @@ There are two ways to define the value of a discriminator for an inheriting inst - Use the schema's name. - Override the schema's name by overriding the property with a new value. If exists, this takes precedence over the schema's name. -As such, inline schema definitions, which do not have a given id, *cannot* be used in polymorphism. +As such, inline schema definitions, which do not have a given id, _cannot_ be used in polymorphism. ##### Schema Object Examples @@ -2332,25 +2302,22 @@ schemas: - color ``` - - - - -#### Security Scheme Object +#### Security Scheme Object Defines a security scheme that can be used by the operations. Supported schemes are: -* User/Password. -* API key (either as user or as password). -* X.509 certificate. -* End-to-end encryption (either symmetric or asymmetric). -* HTTP authentication. -* HTTP API key. -* OAuth2's common flows (Implicit, Resource Owner Protected Credentials, Client Credentials and Authorization Code) as defined in [RFC6749](https://tools.ietf.org/html/rfc6749). -* [OpenID Connect Discovery](https://tools.ietf.org/html/draft-ietf-oauth-discovery-06). -* SASL (Simple Authentication and Security Layer) as defined in [RFC4422](https://tools.ietf.org/html/rfc4422). +- User/Password. +- API key (either as user or as password). +- X.509 certificate. +- End-to-end encryption (either symmetric or asymmetric). +- HTTP authentication. +- HTTP API key. +- OAuth2's common flows (Implicit, Resource Owner Protected Credentials, Client Credentials and Authorization Code) as defined in [RFC6749](https://tools.ietf.org/html/rfc6749). +- [OpenID Connect Discovery](https://tools.ietf.org/html/draft-ietf-oauth-discovery-06). +- SASL (Simple Authentication and Security Layer) as defined in [RFC4422](https://tools.ietf.org/html/rfc4422). ##### Fixed Fields + Field Name | Type | Applies To | Description ---|:---:|---|--- type | `string` | Any | **REQUIRED**. The type of the security scheme. Valid values are `"userPassword"`, `"apiKey"`, `"X509"`, `"symmetricEncryption"`, `"asymmetricEncryption"`, `"httpApiKey"`, `"http"`, `"oauth2"`, `"openIdConnect"`, `"plain"`, `"scramSha256"`, `"scramSha512"`, and `"gssapi"`. @@ -2507,11 +2474,12 @@ scopes: type: scramSha512 ``` -#### OAuth Flows Object +#### OAuth Flows Object Allows configuration of the supported OAuth Flows. ##### Fixed Fields + Field Name | Type | Description ---|:---:|--- implicit| [OAuth Flow Object](#oauthFlowObject) | Configuration for the OAuth Implicit flow. @@ -2521,11 +2489,12 @@ Field Name | Type | Description This object MAY be extended with [Specification Extensions](#specificationExtensions). -#### OAuth Flow Object +#### OAuth Flow Object Configuration details for a supported OAuth Flow ##### Fixed Fields + Field Name | Type | Applies To | Description ---|:---:|---|--- authorizationUrl | `string` | `oauth2` (`"implicit"`, `"authorizationCode"`) | **REQUIRED**. The authorization URL to be used for this flow. This MUST be in the form of an absolute URL. @@ -2556,15 +2525,13 @@ availableScopes: read:pets: read your pets ``` +### Correlation ID Object - -### Correlation ID Object - -An object that specifies an identifier at design time that can used for message tracing and correlation. +An object that specifies an identifier at design time that can used for message tracing and correlation. For specifying and computing the location of a Correlation ID, a [runtime expression](#runtimeExpression) is used. -##### Fixed Fields +#### Fixed Fields Field Name | Type | Description ---|:---|--- @@ -2587,14 +2554,14 @@ description: Default Correlation ID location: $message.header#/correlationId ``` -### Runtime Expression +### Runtime Expression A runtime expression allows values to be defined based on information that will be available within the message. This mechanism is used by [Correlation ID Object](#correlationIdObject) and [Operation Reply Address Object](#operationReplyAddressObject). The runtime expression is defined by the following [ABNF](https://tools.ietf.org/html/rfc5234) syntax: -``` +```text expression = ( "$message" "." source ) source = ( header-reference | payload-reference ) header-reference = "header" ["#" fragment] @@ -2604,7 +2571,7 @@ The runtime expression is defined by the following [ABNF](https://tools.ietf.org The table below provides examples of runtime expressions and examples of their use in a value: -##### Examples +#### Examples Source Location | Example expression | Notes ---|:---|:---| @@ -2613,7 +2580,7 @@ Message Payload Property | `$message.payload#/messageId` | Correlation ID is set Runtime expressions preserve the type of the referenced value. -### Traits Merge Mechanism +### Traits Merge Mechanism Traits MUST be merged with the target object using the [JSON Merge Patch](https://tools.ietf.org/html/rfc7386) algorithm in the same order they are defined. A property on a trait MUST NOT override the same property on the target object. @@ -2639,7 +2606,7 @@ tags: - name: user ``` -### Specification Extensions +### Specification Extensions While the AsyncAPI Specification tries to accommodate most use cases, additional data can be added to extend the specification at certain points. @@ -2647,11 +2614,11 @@ The extensions properties are implemented as patterned fields that are always pr Field Pattern | Type | Description ---|:---:|--- -`^x-[\w\d\-\_]+$` | Any | Allows extensions to the AsyncAPI Schema. The field name MUST begin with `x-`, for example, `x-internal-id`. The value can be `null`, a primitive, an array or an object. Can have any valid JSON format value. +`^x-[\w\d\.\x2d_]+$` | Any | Allows extensions to the AsyncAPI Schema. The field name MUST begin with `x-`, for example, `x-internal-id`. The value can be `null`, a primitive, an array or an object. Can have any valid JSON format value. The extensions may or may not be supported by the available tooling, but those may be extended as well to add requested support (if tools are internal or open-sourced). -### Data Type Formats +### Data Type Formats Primitives have an optional modifier property: `format`. The AsyncAPI specification uses several known formats to more finely define the data type being used. @@ -2662,7 +2629,6 @@ Tools that do not recognize a specific `format` MAY default back to the `type` a The formats defined by the AsyncAPI Specification are: - Common Name | `type` | [`format`](#dataTypeFormat) | Comments ----------- | ------ | -------- | -------- integer | `integer` | `int32` | signed 32 bits