Add support for building a go app without any go modules specified

README.md

@@ -127,7 +127,7 @@ Internally, `lambda-builder` detects a given language and builds the app accordi
     - dotnetcore3.1
 - `go`
   - default build image: `lambci/lambda:build-go1.x`
-  - requirement: `go.mod`
+  - requirement: `go.mod` or `main.go`
   - runtimes:
     - provided.al2
 - `nodejs`

builders/go.go

@@ -24,7 +24,11 @@ func NewGoBuilder(config Config) (GoBuilder, error) {
 }
 
 func (b GoBuilder) Detect() bool {
-	if io.FileExistsInDirectory(b.Config.WorkingDirectory, "go.sum") {
+	if io.FileExistsInDirectory(b.Config.WorkingDirectory, "go.mod") {
+		return true
+	}
+
+	if io.FileExistsInDirectory(b.Config.WorkingDirectory, "main.go") {
 		return true
 	}
 
@@ -76,8 +80,13 @@ puts-step() {
 }
 
 install-gomod() {
-  puts-step "Downloading dependencies via go mod"
-  go mod download 2>&1 | indent
+  if [[ -f "go.mod" ]]; then
+    puts-step "Downloading dependencies via go mod"
+    go mod download 2>&1 | indent
+  else
+    puts-step "Missing go.mod, downloading dependencies via go get"
+    go get
+  fi
 
   puts-step "Compiling via go build"
   go build -o bootstrap main.go 2>&1 | indent

test.bats

@@ -34,6 +34,13 @@ teardown_file() {
   [[ "$status" -eq 0 ]]
 }
 
+@test "[build] go without go modules" {
+  run $LAMBDA_BUILDER_BIN build --working-directory tests/go-nomod
+  echo "output: $output"
+  echo "status: $status"
+  [[ "$status" -eq 0 ]]
+}
+
 @test "[build] hooks" {
   run $LAMBDA_BUILDER_BIN build --working-directory tests/hooks
   echo "output: $output"

tests/go-nomod/main.go

@@ -0,0 +1,20 @@
+package main
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/aws/aws-lambda-go/lambda"
+)
+
+type MyEvent struct {
+	Name string `json:"name"`
+}
+
+func HandleRequest(ctx context.Context, name MyEvent) (string, error) {
+	return fmt.Sprintf("Hello %s!", name.Name), nil
+}
+
+func main() {
+	lambda.Start(HandleRequest)
+}

tests/go-nomod/test.bats

@@ -0,0 +1,61 @@
+#!/usr/bin/env bats
+
+export LAMBDA_ROLE="arn:aws:iam::aws:policy/service-role/AWSLambdaBasicExecutionRole"
+export AWS_ACCOUNT_ID="$(aws sts get-caller-identity | jq -r ".Account")"
+export LAMBDA_FUNCTION_NAME=lambda-go1x
+export LAMBDA_RUNTIME=provided.al2
+export LAMBDA_HANDLER=bootstrap
+
+setup() {
+  aws lambda delete-function --function-name "$LAMBDA_FUNCTION_NAME" 2>/dev/null || true
+  aws iam detach-role-policy --role-name "$LAMBDA_FUNCTION_NAME" --policy-arn arn:aws:iam::aws:policy/service-role/AWSLambdaBasicExecutionRole 2>/dev/null || true
+  aws iam delete-role --role-name "$LAMBDA_FUNCTION_NAME" 2>/dev/null || true
+}
+
+teardown() {
+  aws lambda delete-function --function-name "$LAMBDA_FUNCTION_NAME" 2>/dev/null || true
+  aws iam detach-role-policy --role-name "$LAMBDA_FUNCTION_NAME" --policy-arn arn:aws:iam::aws:policy/service-role/AWSLambdaBasicExecutionRole 2>/dev/null || true
+  aws iam delete-role --role-name "$LAMBDA_FUNCTION_NAME" 2>/dev/null || true
+}
+
+@test "aws test" {
+  run /bin/bash -c "lambda-builder build"
+  echo "output: $output"
+  echo "status: $status"
+  [[ "$status" -eq 0 ]]
+
+  run /bin/bash -c "aws iam create-role --role-name '$LAMBDA_FUNCTION_NAME' --tags 'Key=app,Value=lambda-builder' --tags 'Key=com.dokku.lambda-builder/runtime,Value=$LAMBDA_RUNTIME'  --assume-role-policy-document '{\"Version\": \"2012-10-17\", \"Statement\": [{ \"Effect\": \"Allow\", \"Principal\": {\"Service\": \"lambda.amazonaws.com\"}, \"Action\": \"sts:AssumeRole\"}]}'"
+  echo "output: $output"
+  echo "status: $status"
+  [[ "$status" -eq 0 ]]
+
+  run /bin/bash -c "aws iam attach-role-policy --role-name '$LAMBDA_FUNCTION_NAME' --policy-arn arn:aws:iam::aws:policy/service-role/AWSLambdaBasicExecutionRole"
+  echo "output: $output"
+  echo "status: $status"
+  [[ "$status" -eq 0 ]]
+
+  run /bin/bash -c "sleep 10"
+  echo "output: $output"
+  echo "status: $status"
+  [[ "$status" -eq 0 ]]
+
+  run /bin/bash -c "aws lambda create-function --function-name '$LAMBDA_FUNCTION_NAME' --package-type Zip --tags 'app=lambda-builder,com.dokku.lambda-builder/runtime=$LAMBDA_RUNTIME' --role 'arn:aws:iam::${AWS_ACCOUNT_ID}:role/$LAMBDA_FUNCTION_NAME' --zip-file fileb://lambda.zip --runtime '$LAMBDA_RUNTIME' --handler '$LAMBDA_HANDLER'"
+  echo "output: $output"
+  echo "status: $status"
+  [[ "$status" -eq 0 ]]
+
+  run /bin/bash -c "sleep 10"
+  echo "output: $output"
+  echo "status: $status"
+  [[ "$status" -eq 0 ]]
+
+  run /bin/bash -c "aws lambda get-function --function-name '$LAMBDA_FUNCTION_NAME'"
+  echo "output: $output"
+  echo "status: $status"
+  [[ "$status" -eq 0 ]]
+
+  run /bin/bash -c "aws lambda invoke --cli-binary-format raw-in-base64-out --function-name '$LAMBDA_FUNCTION_NAME' --payload '{\"name\": \"World\"}' response.json"
+  echo "output: $output"
+  echo "status: $status"
+  [[ "$status" -eq 0 ]]
+}