Fix a panic that could occur when context was omitted (#83)

I could have sworn the context property was required, but evidently it
isn't and we weren't handling the case when it was missing.

This PR updates things to set a default location of the current
directory if the context is absent. Some unit tests are also added.

Fixes #78.

CHANGELOG.md

@@ -4,6 +4,7 @@
 
 - Fixed the default value for `ACTIONS_CACHE_URL` when using GitHub action caching. (https://github.com/pulumi/pulumi-docker-build/pull/80)
 - Fixed Java SDK publishing. (https://github.com/pulumi/pulumi-docker-build/pull/89)
+- Fixed a panic that could occur when `context` was omitted. (https://github.com/pulumi/pulumi-docker-build/pull/83)
 
 ## 0.0.2 (2024-04-25)
 

Makefile

@@ -107,6 +107,7 @@ define example
 		--language $(1) \
 		--out ${WORKING_DIR}/examples/$(1)
 	cp -r ${WORKING_DIR}/examples/app ${WORKING_DIR}/examples/$(1)/app
+	cp ${WORKING_DIR}/examples/yaml/.dockerignore ${WORKING_DIR}/examples/$(1)/.dockerignore
 endef
 
 up::

examples/dotnet/.dockerignore

@@ -0,0 +1,2 @@
+command-output
+tmp

examples/dotnet/Program.cs

@@ -239,10 +239,6 @@ COPY hello.c ./
 RUN echo ""This uses an inline Dockerfile! 👍""
 ",
         },
-        Context = new DockerBuild.Inputs.BuildContextArgs
-        {
-            Location = "./app",
-        },
     });
 
     var dockerLoad = new DockerBuild.Image("dockerLoad", new()

examples/go/.dockerignore

@@ -0,0 +1,2 @@
+command-output
+tmp

examples/go/main.go

@@ -207,9 +207,6 @@ func main() {
 			Dockerfile: &dockerbuild.DockerfileArgs{
 				Inline: pulumi.String("FROM alpine\nRUN echo \"This uses an inline Dockerfile! 👍\"\n"),
 			},
-			Context: &dockerbuild.BuildContextArgs{
-				Location: pulumi.String("./app"),
-			},
 		})
 		if err != nil {
 			return err

examples/java/.dockerignore

@@ -0,0 +1,2 @@
+command-output
+tmp

examples/java/src/main/java/generated_program/App.java

@@ -185,9 +185,6 @@ public static void stack(Context ctx) {
 RUN echo "This uses an inline Dockerfile! 👍"
                 """)
                 .build())
-            .context(BuildContextArgs.builder()
-                .location("./app")
-                .build())
             .build());
 
         var dockerLoad = new Image("dockerLoad", ImageArgs.builder()        

examples/nodejs/.dockerignore

@@ -0,0 +1,2 @@
+command-output
+tmp

examples/nodejs/index.ts

@@ -154,9 +154,6 @@ const inline = new docker_build.Image("inline", {
 RUN echo "This uses an inline Dockerfile! 👍"
 `,
     },
-    context: {
-        location: "./app",
-    },
 });
 const dockerLoad = new docker_build.Image("dockerLoad", {
     push: false,

examples/python/.dockerignore

@@ -0,0 +1,2 @@
+command-output
+tmp

examples/python/__main__.py

@@ -141,9 +141,6 @@
         inline="""FROM alpine
 RUN echo "This uses an inline Dockerfile! 👍"
 """,
-    ),
-    context=docker_build.BuildContextArgs(
-        location="./app",
     ))
 docker_load = docker_build.Image("dockerLoad",
     push=False,

examples/yaml/.dockerignore

@@ -0,0 +1,2 @@
+command-output
+tmp

examples/yaml/Pulumi.yaml

@@ -166,8 +166,6 @@ resources:
         inline: |
           FROM alpine
           RUN echo "This uses an inline Dockerfile! 👍"
-      context:
-        location: "./app"
 
   # docker buildx build --load .
   dockerLoad:

provider/cmd/pulumi-resource-docker-build/schema.json

@@ -1165,7 +1165,7 @@
         },
         "context": {
           "$ref": "#/types/docker-build:index:BuildContext",
-          "description": "Build context settings.\n\nEquivalent to Docker's `PATH | URL | -` positional argument."
+          "description": "Build context settings. Defaults to the current directory.\n\nEquivalent to Docker's `PATH | URL | -` positional argument."
         },
         "contextHash": {
           "type": "string",
@@ -1309,7 +1309,7 @@
         },
         "context": {
           "$ref": "#/types/docker-build:index:BuildContext",
-          "description": "Build context settings.\n\nEquivalent to Docker's `PATH | URL | -` positional argument."
+          "description": "Build context settings. Defaults to the current directory.\n\nEquivalent to Docker's `PATH | URL | -` positional argument."
         },
         "dockerfile": {
           "$ref": "#/types/docker-build:index:Dockerfile",

provider/internal/context.go

@@ -26,12 +26,14 @@ import (
 	"os"
 	"path"
 	"path/filepath"
+	"slices"
 	"syscall"
 
 	buildx "github.com/docker/buildx/build"
 	"github.com/moby/patternmatcher/ignorefile"
 	"github.com/spf13/afero"
 	"github.com/tonistiigi/fsutil"
+	"golang.org/x/exp/maps"
 
 	"github.com/pulumi/pulumi-go-provider/infer"
 	"github.com/pulumi/pulumi/sdk/v3/go/common/util/contract"
@@ -90,7 +92,9 @@ func (c *Context) Annotate(a infer.Annotator) {
 
 // validate returns a non-nil CheckError if the Context is invalid. The
 // returned Dockerfile may have defaults set to match Docker's default
-// handling. The returned Dockerfile should be validated separately.
+// handling. The returned Dockerfile should be validated separately. Non-nil
+// values are returned even in the case of errors to allow additional
+// validation to be performed.
 func (bc *BuildContext) validate(preview bool, d *Dockerfile) (*Dockerfile, *Context, error) {
 	if d == nil {
 		d = &Dockerfile{}
@@ -107,6 +111,11 @@ func (bc *BuildContext) validate(preview bool, d *Dockerfile) (*Dockerfile, *Con
 		// a build later.
 		return d, c, nil
 	}
+	// If this isn't a preview but our location still isn't set, default it to
+	// the current directory.
+	if c.Location == "" {
+		c.Location = "."
+	}
 
 	if buildx.IsRemoteURL(c.Location) {
 		// We assume remote URLs are always valid.
@@ -225,8 +234,11 @@ func hashBuildContext(
 		}
 	}
 
-	// Hash any local named contexts.
-	for _, namedContext := range namedContexts {
+	// Hash any local named contexts. Sort keys for stable iteration order.
+	keys := maps.Keys(namedContexts)
+	slices.Sort(keys)
+	for _, key := range keys {
+		namedContext := namedContexts[key]
 		if isLocalDir(fs, namedContext) {
 			fs, err := rootFS(namedContext, excludes)
 			if err != nil {

provider/internal/context_test.go

@@ -33,71 +33,77 @@ func TestValidateContext(t *testing.T) {
 	t.Parallel()
 	tests := []struct {
 		name    string
-		c       Context
+		c       *BuildContext
 		givenD  Dockerfile
 		preview bool
 
 		wantD   *Dockerfile
+		wantC   *Context
 		wantErr string
 	}{
 		{
 			name: "relative",
-			c: Context{
+			c: &BuildContext{Context: Context{
 				Location: "../internal/../internal/testdata/noop",
-			},
+			}},
 			wantD: &Dockerfile{
 				Location: "../internal/testdata/noop/Dockerfile",
 			},
 		},
 		{
 			name: "missing directory",
-			c: Context{
+			c: &BuildContext{Context: Context{
 				Location: "/does/not/exist/",
-			},
+			}},
 			wantErr: "not a valid directory",
 		},
 		{
 			name: "missing default Dockerfile",
-			c: Context{
+			c: &BuildContext{Context: Context{
 				Location: "testdata",
-			},
+			}},
 			wantD: &Dockerfile{Location: "testdata/Dockerfile"},
 		},
 		{
 			name: "with explicit Dockerfile",
-			c: Context{
+			c: &BuildContext{Context: Context{
 				Location: "testdata",
-			},
+			}},
 			givenD: Dockerfile{
 				Location: "testdata/Dockerfile.invalid",
 			},
 		},
 		{
 			name:  "default location",
-			c:     Context{},
+			c:     &BuildContext{Context: Context{}},
 			wantD: &Dockerfile{Location: "Dockerfile"},
 		},
 		{
 			name: "remote context doesn't default to local Dockerfile",
-			c: Context{
+			c: &BuildContext{Context: Context{
 				Location: "https://raw.githubusercontent.com/pulumi/pulumi-docker/api-types/provider/testdata/Dockerfile",
-			},
+			}},
 			wantD: &Dockerfile{},
 		},
 		{
 			name:    "preview",
-			c:       Context{},
+			c:       &BuildContext{Context: Context{}},
 			preview: true,
 		},
+		{
+			name:  "missing context defaults to current directory",
+			c:     nil,
+			wantC: &Context{Location: "."},
+			wantD: &Dockerfile{Location: "Dockerfile"},
+		},
 	}
 
 	for _, tt := range tests {
 		tt := tt
 		t.Run(tt.name, func(t *testing.T) {
 			t.Parallel()
 
-			bc := &BuildContext{Context: tt.c}
-			d, _, err := bc.validate(tt.preview, &tt.givenD)
+			d, c, err := tt.c.validate(tt.preview, &tt.givenD)
 
 			if tt.wantErr == "" {
 				assert.NoError(t, err)
@@ -109,6 +115,9 @@ func TestValidateContext(t *testing.T) {
 				assert.Equal(t, tt.wantD.Location, d.Location)
 				assert.Equal(t, tt.wantD.Inline, d.Inline)
 			}
+			if tt.wantC != nil {
+				assert.Equal(t, tt.wantC.Location, c.Location)
+			}
 		})
 	}
 }

provider/internal/host.go

@@ -16,8 +16,10 @@ package internal
 
 import (
 	"context"
+	"fmt"
 	"path/filepath"
 	"sync"
+	"time"
 
 	"github.com/docker/buildx/builder"
 	"github.com/docker/buildx/store/storeutil"
@@ -72,7 +74,7 @@ func (h *host) builderFor(build Build) (*cachedBuilder, error) {
 
 	txn, release, err := storeutil.GetStore(h.cli)
 	if err != nil {
-		return nil, err
+		return nil, fmt.Errorf("getting store: %w", err)
 	}
 	defer release()
 
@@ -86,7 +88,7 @@ func (h *host) builderFor(build Build) (*cachedBuilder, error) {
 		builder.WithStore(txn),
 	)
 	if err != nil {
-		return nil, err
+		return nil, fmt.Errorf("new builder: %w", err)
 	}
 
 	// If we didn't request a particular builder, and we loaded a default
@@ -95,7 +97,7 @@ func (h *host) builderFor(build Build) (*cachedBuilder, error) {
 	if b.Driver == "" && opts.Builder == "" {
 		builders, err := builder.GetBuilders(h.cli, txn)
 		if err != nil {
-			return nil, err
+			return nil, fmt.Errorf("getting builders: %w", err)
 		}
 	nextbuilder:
 		for _, bb := range builders {
@@ -128,6 +130,7 @@ func (h *host) builderFor(build Build) (*cachedBuilder, error) {
 	}
 
 	if b.Driver == "" && opts.Builder == "" {
+
 		// If we STILL don't have a builder, create a docker-container instance.
 		b, err = builder.Create(
 			context.Background(),
@@ -136,7 +139,12 @@ func (h *host) builderFor(build Build) (*cachedBuilder, error) {
 			builder.CreateOpts{Driver: "docker-container"},
 		)
 		if err != nil {
-			return nil, err
+			return nil, fmt.Errorf("creating builder: %w", err)
+		}
+		ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
+		defer cancel()
+		if _, err := b.Boot(ctx); err != nil {
+			return nil, fmt.Errorf("booting builder: %w", err)
 		}
 	}
 
@@ -145,7 +153,7 @@ func (h *host) builderFor(build Build) (*cachedBuilder, error) {
 	// drivers that are unknown to us.
 	nodes, err := b.LoadNodes(context.Background())
 	if err != nil && !build.ShouldExec() {
-		return nil, err
+		return nil, fmt.Errorf("loading nodes: %w", err)
 	}
 
 	cached := &cachedBuilder{name: b.Name, driver: b.Driver, nodes: nodes}

provider/internal/image.go

@@ -153,7 +153,7 @@ func (ia *ImageArgs) Annotate(a infer.Annotator) {
 		Equivalent to Docker's "--cache-to" flag.
 	`))
 	a.Describe(&ia.Context, dedent(`
-		Build context settings.
+		Build context settings. Defaults to the current directory.
 
 		Equivalent to Docker's "PATH | URL | -" positional argument.
 	`))
@@ -546,6 +546,10 @@ func (ia *ImageArgs) validate(preview bool) (controllerapi.BuildOptions, error)
 		multierr = errors.Join(multierr, err)
 	}
 	ia.Dockerfile = dockerfile
+	// Set a default context if one wasn't provided.
+	if ia.Context == nil {
+		ia.Context = &BuildContext{Context: *context}
+	}
 
 	if err := ia.Dockerfile.validate(preview, context); err != nil {
 		multierr = errors.Join(multierr, err)