Support resource copy into Fn Docker image via func.yaml (#591)

Author: bepearso

common/common.go

@@ -15,6 +15,7 @@ import (
 	"os/exec"
 	"os/signal"
 	"path/filepath"
+	"strconv"
 	"strings"
 	"time"
 	"unicode"
@@ -388,6 +389,15 @@ func writeTmpDockerfile(helper langs.LangHelper, dir string, ff *FuncFile) (stri
 		dfLines = append(dfLines, fmt.Sprintf("FROM %s", ri))
 		dfLines = append(dfLines, "WORKDIR /function")
 		dfLines = append(dfLines, helper.DockerfileCopyCmds()...)
+
+		resources := ff.CopyResources
+		for _, resource := range resources {
+			if Exists(resource.From) {
+				dfLines = append(dfLines, fmt.Sprintf("COPY %s %s", strconv.Quote(resource.From), strconv.Quote(resource.To)))
+			} else {
+				return "", errors.New(fmt.Sprintf("Filepath %s does not exist", resource.From))
+			}
+		}
 	}
 	if ff.Entrypoint != "" {
 		dfLines = append(dfLines, fmt.Sprintf("ENTRYPOINT [%s]", stringToSlice(ff.Entrypoint)))
@@ -442,6 +452,15 @@ func writeTmpDockerfileV20180708(helper langs.LangHelper, dir string, ff *FuncFi
 		dfLines = append(dfLines, fmt.Sprintf("FROM %s", ri))
 		dfLines = append(dfLines, "WORKDIR /function")
 		dfLines = append(dfLines, helper.DockerfileCopyCmds()...)
+
+		resources := ff.CopyResources
+		for _, resource := range resources {
+			if Exists(resource.From) {
+				dfLines = append(dfLines, fmt.Sprintf("COPY %s %s", strconv.Quote(resource.From), strconv.Quote(resource.To)))
+			} else {
+				return "", errors.New(fmt.Sprintf("Filepath %s does not exist", resource.From))
+			}
+		}
 	}
 	if ff.Entrypoint != "" {
 		dfLines = append(dfLines, fmt.Sprintf("ENTRYPOINT [%s]", stringToSlice(ff.Entrypoint)))

common/funcfile.go

@@ -52,6 +52,11 @@ type Expects struct {
 	Config []inputVar `yaml:"config" json:"config"`
 }
 
+type copyResources struct {
+	From string `yaml:"from,omitempty" json:"from,omitempty"`
+	To string `yaml:"to,omitempty" json:"to,omitempty"`
+}
+
 // FuncFile defines the internal structure of a func.yaml/json/yml
 type FuncFile struct {
 	// just for posterity, this won't be set on old files, but we can check that
@@ -70,6 +75,9 @@ type FuncFile struct {
 	RunImage    string   `yaml:"run_image,omitempty" json:"run_image,omitempty"`     // Image to use for running
 	ContentType string   `yaml:"content_type,omitempty" json:"content_type,omitempty"`
 
+	//Allows resource copy 
+	CopyResources []copyResources `yaml:"copy_resources,omitempty" json:"copy_resources,omitempty"`
+
 	// Route params
 	// TODO embed models.Route
 	Type        string                 `yaml:"type,omitempty" json:"type,omitempty"`
@@ -102,6 +110,8 @@ type FuncFileV20180708 struct {
 	Timeout      *int32 `yaml:"timeout,omitempty" json:"timeout,omitempty"`
 	IDLE_timeout *int32 `yaml:"idle_timeout,omitempty" json:"idle_timeout,omitempty"`
 
+	CopyResources []copyResources `yaml:"copy_resources,omitempty" json:"copy_resources,omitempty"`
+
 	Config      map[string]string      `yaml:"config,omitempty" json:"config,omitempty"`
 	Annotations map[string]interface{} `yaml:"annotations,omitempty" json:"annotations,omitempty"`
 

test/cli_copy_resource_test.go

@@ -0,0 +1,65 @@
+package test
+
+import (
+	"strings"
+	"testing"
+
+	"github.com/fnproject/cli/testharness"
+)
+
+func TestResourceCopy(t *testing.T) {
+
+	const testFuncSource = `package main
+	import (
+		"context"
+		"io"
+		"os" 
+		fdk "github.com/fnproject/fdk-go"
+	)
+	func main() {
+		fdk.Handle(fdk.HandlerFunc(myHandler))
+	}
+	func myHandler(ctx context.Context, in io.Reader, out io.Writer) {
+		testFile,err := os.Open("/testfile.txt")
+		if err != nil {
+			panic(err.Error()) 
+		}
+		defer testFile.Close()
+		io.Copy(out,testFile) 
+	}
+	`
+
+	const funcYaml = 
+`schema_version: 20180708
+name: filefn
+version: 0.0.1
+runtime: go
+entrypoint: ./func
+copy_resources:
+   - from: testfile.txt
+     to: /
+`
+
+	const gomod = `module func`
+	const testFile = `hello world!`
+
+	t.Parallel()
+	h := testharness.Create(t)
+	defer h.Cleanup()
+
+	appName := h.NewAppName()
+
+	h.WithFile("func.yaml", funcYaml, 0644)
+	h.WithFile("func.go", testFuncSource, 0644)
+	h.WithFile("testfile.txt", testFile, 0644)
+	h.WithFile("go.mod", gomod, 0644)
+
+	h.Fn("deploy", "--app", appName, "--local", "--create-app").AssertSuccess()
+
+	res := h.Fn("invoke", appName, "filefn")
+
+	res.AssertSuccess()
+	if strings.TrimSpace(res.Stdout) != testFile {
+		t.Fatalf("Expected result to be '%s', got '%s'", testFile, res.Stdout)
+	}
+}