Fast Cloudevents

A small and configurable implementation of the cloudevents spec for Go, with support for fasthttp.

This package exists to replace the heavy, complex, and difficult to use (in my opinion) go-sdk.

Example

See main.go and fastce/examples.go.

package main

import (
    fastce "github.com/creativecactus/fast-cloudevents-go/fastce"
    jsonce "github.com/creativecactus/fast-cloudevents-go/jsonce"
)

func main(){      
    // An example of a custom unmarshal function
    MyMapToCE := func(cm jsonce.CEMap)(ce jsonce.CloudEvent, err error){
        // In this example, we still want to perform the DefaultCEToMap validation
        // But we will automatically generate an ID if it is not present
        if id, ok := cm["id"].(string); !ok || len(id) < 1 {
            cm["id"] = "SomeRandomRuntimeGeneratedID"
        }
        return jsonce.DefaultMapToCE(cm)
    }

    handler := func(ces jsonce.CloudEvents)(res jsonce.CloudEvents, err error){
        // This is a simple echo server
        res = ces
        return
    }
    CEServer{}.ListenAndServeCE(listenAddr,jsonce.DefaultCEToMap,MyMapToCE,handler)
}

Notes

• While most functions operate on []jsonce.CloudEvent (AKA jsonce.CloudEvents), structured and binary modes will discard all but the first event.
• In binary mode, all extension headers are treated as strings. This might look strange when sending and receiving in different modes. To support receiving non-strings in binary mode, use a custom unmarshal mapper as in the above example.

Features

• High level server and client types: CEClient, CEServer
• Mid level getters and setters for fasthttp request/response: GetEvents, SetEvents, SendEvents, RecvEvents
• Flexible CloudEvents type can be used standalone
• Lightweight, easy to audit, heavily tested
• Good support for CloudEvents spec
• Easy to use

V1 spec

See JSON, HTTP specifications.

fasthttp support:

• 3.1 Binary Content Mode ☑️ Send and receive.
• 3.2 Structured Content Mode ☑️ Send and receive.
• 3.3. Batched Content Mode ☑️ Send and receive.

JSON support:

• 2.2. Type System Mapping ☑️ Supported on known fields, user must enforce for extensions as needed using type assertion.
• 2.4. JSONSchema Validation ❌ Not tested yet.
• 3. Envelope 🕙 Fully suported, partially complaint.
• 4. JSON Batch Format ☑️ Supported.

Conventions

• cec means CloudEvent Client
• ce and ces mean CloudEvent and CloudEvents respectively
• res is sometimes used to refer to a second CloudEvents if there are multiple
• re and res mean Response CloudEvent and Response CloudEvents respectively
• Get/Set and Send/Recv refer to Servers and Clients writing/reading events, respectively

See also

FastHTTP best practices.