Add package command (#385)

Add package command support: This PR adds package command to CLI. package provides some useful subcommands to use such as packages CRUD and display package detail information. Also it is able to reuse existing package at function creation.

* Check function existence before creating package

* Check package existence

* Add support for downloading archive from given url

The functionality was supported before e238776bf7. Add this functionality back for more flexible usage.

* Add output flag to save archive content in specific file

* Add logs when package create/update

* Fix fnCreate requires environment argument when a pkg is specified

* Fix fnUpdate failed to update function pkg info when a package is specified

* Add package command test

* Fix wrong python test image in test script

* Remove package description fields

* Fix package command not update package but creating a new one

* Set package as pending status only when there is no deploy archive

* Rename function from fetchArchiveFromArbitraryURL to downloadToTempFile

* Use io.Copy to prevent loading all body into memory

* Revise some messages

* Allow user to update package build command

* Allow user to update package content when using function update

* Retrieve pkgName from function packageref if it’s not specified

* Fix function failed to update due to resource conflict

* Fix test case failure due to single quote

* kick ci

* Fix failed to update function packageRef

* kick ci

* kick ci

test/tests/test_package_command.sh

@@ -0,0 +1,85 @@
+#!/bin/bash
+
+set -euo pipefail
+
+# Use package command to create two packages one with source 
+# archive and the other with deploy archive. Also, create a 
+# function to test the packages created by package command are 
+# able to work.
+
+ROOT=$(dirname $0)/../..
+PYTHON_RUNTIME_IMAGE=gcr.io/fission-ci/python3-env:test
+PYTHON_BUILDER_IMAGE=gcr.io/fission-ci/python3-env-builder:test
+
+fn=python-srcbuild-$(date +%s)
+
+waitBuild() {
+    echo "Waiting for builder manager to finish the build"
+    
+    while true; do
+      kubectl --namespace default get packages $1 -o jsonpath='{.status.buildstatus}'|grep succeeded
+      if [[ $? -eq 0 ]]; then
+          break
+      fi
+    done
+}
+export -f waitBuild
+
+checkFunctionResponse() {
+    echo "Doing an HTTP GET on the function's route"
+    response=$(curl http://$FISSION_ROUTER/$1)
+
+    echo "Checking for valid response"
+    echo $response
+    echo $response | grep -i "$2"
+}
+
+echo "Pre-test cleanup"
+fission env delete --name python || true
+
+echo "Creating python env"
+fission env create --name python --image $PYTHON_RUNTIME_IMAGE --builder $PYTHON_BUILDER_IMAGE
+trap "fission env delete --name python" EXIT
+
+echo "Waiting for env builder to catch up"
+sleep 30
+
+echo "Creating pacakage with source archive"
+zip -jr demo-src-pkg.zip $ROOT/examples/python/sourcepkg/
+pkgName=$(fission package create --src demo-src-pkg.zip --env python --buildcmd "./build.sh"| cut -f2 -d' '| tr -d \')
+
+# wait for build to finish at most 60s
+timeout 60s bash -c "waitBuild $pkgName"
+
+echo "Creating function " $fn
+fission fn create --name $fn --pkg $pkgName --entrypoint "user.main"
+trap "fission fn delete --name $fn" EXIT
+
+echo "Creating route"
+fission route create --function $fn --url /$fn --method GET
+
+echo "Waiting for router to catch up"
+sleep 3
+  
+checkFunctionResponse $fn 'a: 1 b: {c: 3, d: 4}'
+
+echo "Creating package with deploy archive"
+mkdir testDir
+touch testDir/__init__.py
+printf 'def main():\n    return "Hello, world!"' > testDir/hello.py
+zip -jr demo-deploy-pkg.zip testDir/
+pkgName=$(fission package create --deploy demo-deploy-pkg.zip --env python| cut -f2 -d' '| tr -d \')
+
+echo "Updating function " $fn
+fission fn update --name $fn --pkg $pkgName --entrypoint "hello.main"
+trap "fission fn delete --name $fn" EXIT
+
+echo "Waiting for router to update cache"
+sleep 3
+
+checkFunctionResponse $fn 'Hello, world!'
+
+# crappy cleanup, improve this later
+kubectl get httptrigger -o name | tail -1 | cut -f2 -d'/' | xargs kubectl delete httptrigger
+
+echo "All done."