Declarative application specifications for Fission (#422)

This change enables users to have declarative specifications for Fission resources. Users can specify their "app" in a set of spec files, and use a new fission CLI command to "apply" these specs to a running cluster.

The new "spec" CLI also includes archiving of local source files, and a file watcher that re-builds archives and uploads them on file changes, and a package build watcher that waits for package builds on the CLI. 

A "--spec" option is also added to "function create", and will be added to other resources in future changes.  This option causes a YAML to be outputted to the specs directory instead of the resource being created on the cluster.

The CLI "fission spec --help" outputs usage information.

examples/go/README.md

@@ -1,40 +1,17 @@
-# Go examples
+# Hello World in Go on Fission
 
-The `go` runtime uses the [`plugin` package](https://golang.org/pkg/plugin/) to dynamically load an HTTP handler.
-
-## Requirements
-
-First, set up your fission deployment with the go environment.
-
-```
-fission env create --name go-env --image fission/go-env:1.8.1
-```
-
-To ensure that you build functions using the same version as the
-runtime, fission provides a docker image and helper script for
-building functions.
-
-## Example Usage
-
-### hello.go
-
-`hello.go` is an very basic HTTP handler returning `"Hello, World!"`.
+`hello.go` is an very simple fission function that says "Hello, World!".
 
 ```bash
-# Download the build helper script
-$ curl https://raw.githubusercontent.com/fission/fission/master/environments/go/builder/go-function-build > go-function-build
-$ chmod +x go-function-build
+# This command creates the environment and function, and waits for the
+# function build.  Look at the YAML files in specs/ for details about
+# how those are specified.
+$ fission spec apply --wait
+1 environment created
+1 package created
+1 function created
 
-# Build the function as a plugin. Outputs result to 'function.so'
-$ go-function-build hello.go
-
-# Upload the function to fission
-$ fission function create --name hello --env go-env --package function.so
-
-# Map /hello to the hello function
-$ fission route create --method GET --url /hello --function hello
-
-# Run the function
-$ curl http://$FISSION_ROUTER/hello
+# This run the function and prints its output
+$ fission function test --name hello
 Hello, World!
 ```

examples/go/hello.go

@@ -4,7 +4,8 @@ import (
 	"net/http"
 )
 
+// Handler is the entry point for this fission function
 func Handler(w http.ResponseWriter, r *http.Request) {
-	msg := "Hello, World!"
+	msg := "Hello, world!\n"
 	w.Write([]byte(msg))
 }

examples/go/specs/env.yaml

@@ -0,0 +1,12 @@
+apiVersion: fission.io/v1
+kind: Environment
+metadata:
+  name: go
+  namespace: default
+spec:
+  version: 2
+  builder:
+    command: build
+    image: fission/go-build-env:20171206-2
+  runtime:
+    image: fission/go-env:20171206

examples/go/specs/fission-deployment-config.yaml

@@ -0,0 +1,6 @@
+# This file is generated by the 'fission spec init' command.
+# See the README in this directory for background and usage information.
+# Do not edit the UID below: that will break 'fission spec apply'
+kind: DeploymentConfig
+name: hello-go
+uid: a8cdb63c-9be8-4a59-9427-89051afecd7b

examples/go/specs/function-hello.yaml

@@ -0,0 +1,38 @@
+kind: ArchiveUploadSpec
+name: hello-go
+include:
+- hello.go
+
+---
+apiVersion: fission.io/v1
+kind: Package
+metadata:
+  creationTimestamp: null
+  name: hello-go-pkg
+  namespace: default
+spec:
+  environment:
+    name: go
+    namespace: default
+  source:
+    type: url
+    url: archive://hello-go
+status:
+  buildstatus: pending
+
+---
+apiVersion: fission.io/v1
+kind: Function
+metadata:
+  creationTimestamp: null
+  name: hello-go
+  namespace: default
+spec:
+  environment:
+    name: go
+    namespace: default
+  package:
+    functionName: Handler
+    packageref:
+      name: hello-go-pkg
+      namespace: default

examples/spec-example/README.md

@@ -0,0 +1,11 @@
+This is the root directory of a declaratively specified fission "application".  The app
+contains source code for one function (a simple "hello world") in the hello/hello.py
+file.
+
+The `specs` directory contains YAML files that specify the Fission environment and
+function.
+
+You can create this app on your cluster by running `fission spec apply` from this
+directory.  See `fission spec --help` for other options.
+
+After applying the spec, you can test the function with `fission fn test --name hello`.

examples/spec-example/hello/build.sh

@@ -0,0 +1,9 @@
+#!/bin/sh
+
+set -e
+
+# check syntax
+python -m compileall -l ${SRC_PKG}
+
+# install deps
+pip install -r ${SRC_PKG}/requirements.txt -t ${SRC_PKG} && cp -r ${SRC_PKG} ${DEPLOY_PKG}

examples/spec-example/hello/hello.py

@@ -0,0 +1,4 @@
+import yaml
+
+def main():
+    return "hello, world!!\n"

examples/spec-example/hello/requirements.txt

@@ -0,0 +1 @@
+pyyaml

examples/spec-example/specs/env.yaml

@@ -0,0 +1,12 @@
+apiVersion: fission.io/v1
+kind: Environment
+metadata:
+  name: python-27
+  namespace: default
+spec:
+  version: 2
+  builder:
+    command: build
+    image: fission/python-build-env-2.7:0.4.0rc
+  runtime:
+    image: fission/python-env-2.7:0.4.0rc

examples/spec-example/specs/fission-config.yaml

@@ -0,0 +1,3 @@
+kind: DeploymentConfig
+name: spec-example
+uid: 27438a48-4191-4b5e-95b2-7793624317b9

examples/spec-example/specs/hello.yaml

@@ -0,0 +1,38 @@
+apiVersion: fission.io/v1
+kind: Function
+metadata:
+  name: hello
+  namespace: default
+spec:
+  environment:
+    name: python-27
+    namespace: default
+  package:
+    packageref:
+      name: hello-pkg
+      namespace: default
+    functionName: hello.main
+
+---
+apiVersion: fission.io/v1
+kind: Package
+metadata:
+  name: hello-pkg
+  namespace: default
+spec:
+  source:
+    url: archive://hello-archive
+  buildcmd: "./build.sh"
+  environment:
+    name: python-27
+    namespace: default
+status:
+  buildstatus: pending
+
+---
+kind: ArchiveUploadSpec
+name: hello-archive
+include:
+  - "hello/*.py"
+  - "hello/*.sh"
+  - "hello/requirements.txt"