Support dockerfile and Dockerfile

Closes #10807

Adds support for `dockerfile` ONLY when `Dockerfile` can't be found.
If we're building from a Dockerfile via stdin/URL then always download
it a `Dockerfile` and ignore the -f flag.

Signed-off-by: Doug Davis <dug@us.ibm.com>

api/client/commands.go

@@ -114,9 +114,10 @@ func (cli *DockerCli) CmdBuild(args ...string) error {
 			if err != nil {
 				return fmt.Errorf("failed to read Dockerfile from STDIN: %v", err)
 			}
-			if *dockerfileName == "" {
-				*dockerfileName = api.DefaultDockerfileName
-			}
+
+			// -f option has no meaning when we're reading it from stdin,
+			// so just use our default Dockerfile name
+			*dockerfileName = api.DefaultDockerfileName
 			context, err = archive.Generate(*dockerfileName, string(dockerfile))
 		} else {
 			context = ioutil.NopCloser(buf)
@@ -156,6 +157,16 @@ func (cli *DockerCli) CmdBuild(args ...string) error {
 			// No -f/--file was specified so use the default
 			*dockerfileName = api.DefaultDockerfileName
 			filename = filepath.Join(absRoot, *dockerfileName)
+
+			// Just to be nice ;-) look for 'dockerfile' too but only
+			// use it if we found it, otherwise ignore this check
+			if _, err = os.Lstat(filename); os.IsNotExist(err) {
+				tmpFN := path.Join(absRoot, strings.ToLower(*dockerfileName))
+				if _, err = os.Lstat(tmpFN); err == nil {
+					*dockerfileName = strings.ToLower(*dockerfileName)
+					filename = tmpFN
+				}
+			}
 		}
 
 		origDockerfile := *dockerfileName // used for error msg

builder/evaluator.go

@@ -28,6 +28,7 @@ import (
 	"strings"
 
 	log "github.com/Sirupsen/logrus"
+	"github.com/docker/docker/api"
 	"github.com/docker/docker/builder/command"
 	"github.com/docker/docker/builder/parser"
 	"github.com/docker/docker/daemon"
@@ -146,7 +147,7 @@ func (b *Builder) Run(context io.Reader) (string, error) {
 		}
 	}()
 
-	if err := b.readDockerfile(b.dockerfileName); err != nil {
+	if err := b.readDockerfile(); err != nil {
 		return "", err
 	}
 
@@ -177,7 +178,23 @@ func (b *Builder) Run(context io.Reader) (string, error) {
 
 // Reads a Dockerfile from the current context. It assumes that the
 // 'filename' is a relative path from the root of the context
-func (b *Builder) readDockerfile(origFile string) error {
+func (b *Builder) readDockerfile() error {
+	// If no -f was specified then look for 'Dockerfile'. If we can't find
+	// that then look for 'dockerfile'.  If neither are found then default
+	// back to 'Dockerfile' and use that in the error message.
+	if b.dockerfileName == "" {
+		b.dockerfileName = api.DefaultDockerfileName
+		tmpFN := filepath.Join(b.contextPath, api.DefaultDockerfileName)
+		if _, err := os.Lstat(tmpFN); err != nil {
+			tmpFN = filepath.Join(b.contextPath, strings.ToLower(api.DefaultDockerfileName))
+			if _, err := os.Lstat(tmpFN); err == nil {
+				b.dockerfileName = strings.ToLower(api.DefaultDockerfileName)
+			}
+		}
+	}
+
+	origFile := b.dockerfileName
+
 	filename, err := symlink.FollowSymlinkInScope(filepath.Join(b.contextPath, origFile), b.contextPath)
 	if err != nil {
 		return fmt.Errorf("The Dockerfile (%s) must be within the build context", origFile)

builder/job.go

@@ -78,10 +78,6 @@ func (b *BuilderJob) CmdBuild(job *engine.Job) engine.Status {
 		}
 	}
 
-	if dockerfileName == "" {
-		dockerfileName = api.DefaultDockerfileName
-	}
-
 	if remoteURL == "" {
 		context = ioutil.NopCloser(job.Stdin)
 	} else if urlutil.IsGitURL(remoteURL) {
@@ -113,6 +109,11 @@ func (b *BuilderJob) CmdBuild(job *engine.Job) engine.Status {
 		if err != nil {
 			return job.Error(err)
 		}
+
+		// When we're downloading just a Dockerfile put it in
+		// the default name - don't allow the client to move/specify it
+		dockerfileName = api.DefaultDockerfileName
+
 		c, err := archive.Generate(dockerfileName, string(dockerFile))
 		if err != nil {
 			return job.Error(err)

docs/sources/reference/api/docker_remote_api_v1.18.md

@@ -1073,10 +1073,13 @@ command*](/reference/builder/#dockerbuilder)).
 
 Query Parameters:
 
--   **dockerfile** - path within the build context to the Dockerfile
+-   **dockerfile** - path within the build context to the Dockerfile. This is 
+        ignored if `remote` is specified and points to an individual filename.
 -   **t** – repository name (and optionally a tag) to be applied to
         the resulting image in case of success
--   **remote** – git or HTTP/HTTPS URI build source
+-   **remote** – A Git repository URI or HTTP/HTTPS URI build source. If the 
+        URI specifies a filename, the file's contents are placed into a file 
+		called `Dockerfile`.
 -   **q** – suppress verbose build output
 -   **nocache** – do not use the cache when building the image
 -   **pull** - attempt to pull the image even if an older image exists locally

docs/sources/reference/commandline/cli.md

@@ -506,21 +506,27 @@ is returned by the `docker attach` command to its caller too:
       --rm=true                Remove intermediate containers after a successful build
       -t, --tag=""             Repository name (and optionally a tag) for the image
 
-Use this command to build Docker images from a Dockerfile and a
-"context".
-
-The files at `PATH` or `URL` are called the "context" of the build. The
-build process may refer to any of the files in the context, for example
-when using an [*ADD*](/reference/builder/#add) instruction.
-When a single Dockerfile is given as `URL` or is piped through `STDIN`
-(`docker build - < Dockerfile`), then no context is set.
-
-When a Git repository is set as `URL`, then the repository is used as
-the context. The Git repository is cloned with its submodules
-(`git clone -recursive`). A fresh `git clone` occurs in a temporary directory
-on your local host, and then this is sent to the Docker daemon as the
-context.  This way, your local user credentials and VPN's etc can be
-used to access private repositories.
+Builds Docker images from a Dockerfile and a "context". A build's context is
+the files located in the specified `PATH` or `URL`.  The build process can
+refer to any of the files in the context. For example, your build can use
+an [*ADD*](/reference/builder/#add) instruction to reference a file in the
+context.
+
+The `URL` parameter can specify the location of a Git repository; in this
+case,  the repository is the context. The Git repository is recursively
+cloned with its submodules.  The system does a fresh `git clone -recursive`
+in a temporary directory on your local host. Then, this clone is sent to
+the Docker daemon as the context. Local clones give you the ability to
+access private repositories using local user credentials, VPN's, and so forth.
+
+Instead of specifying a context, you can pass a single Dockerfile in the
+`URL` or pipe the file in via `STDIN`.  To pipe a Dockerfile from `STDIN`:
+
+	docker build - < Dockerfile
+
+If you use STDIN or specify a `URL`, the system places the contents into a
+file called `Dockerfile`, and any `-f`, `--file` option is ignored. In this 
+scenario, there is no context.
 
 If a file named `.dockerignore` exists in the root of `PATH` then it
 is interpreted as a newline-separated list of exclusion patterns.
@@ -529,7 +535,7 @@ will be excluded from the context. Globbing is done using Go's
 [filepath.Match](http://golang.org/pkg/path/filepath#Match) rules.
 
 Please note that `.dockerignore` files in other subdirectories are
-considered as normal files. Filepaths in .dockerignore are absolute with
+considered as normal files. Filepaths in `.dockerignore` are absolute with
 the current directory as the root. Wildcards are allowed but the search
 is not recursive.
 

integration-cli/docker_api_containers_test.go

@@ -353,6 +353,106 @@ func TestBuildApiDockerfilePath(t *testing.T) {
 	logDone("container REST API - check build w/bad Dockerfile path")
 }
 
+func TestBuildApiDockerFileRemote(t *testing.T) {
+	server, err := fakeStorage(map[string]string{
+		"testD": `FROM busybox
+COPY * /tmp/
+RUN find /tmp/`,
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer server.Close()
+
+	buf, err := sockRequestRaw("POST", "/build?dockerfile=baz&remote="+server.URL+"/testD", nil, "application/json")
+	if err != nil {
+		t.Fatalf("Build failed: %s", err)
+	}
+
+	out := string(buf)
+	if !strings.Contains(out, "/tmp/Dockerfile") ||
+		strings.Contains(out, "/tmp/baz") {
+		t.Fatalf("Incorrect output: %s", out)
+	}
+
+	logDone("container REST API - check build with -f from remote")
+}
+
+func TestBuildApiLowerDockerfile(t *testing.T) {
+	git, err := fakeGIT("repo", map[string]string{
+		"dockerfile": `FROM busybox
+RUN echo from dockerfile`,
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer git.Close()
+
+	buf, err := sockRequestRaw("POST", "/build?remote="+git.RepoURL, nil, "application/json")
+	if err != nil {
+		t.Fatalf("Build failed: %s\n%q", err, buf)
+	}
+
+	out := string(buf)
+	if !strings.Contains(out, "from dockerfile") {
+		t.Fatalf("Incorrect output: %s", out)
+	}
+
+	logDone("container REST API - check build with lower dockerfile")
+}
+
+func TestBuildApiBuildGitWithF(t *testing.T) {
+	git, err := fakeGIT("repo", map[string]string{
+		"baz": `FROM busybox
+RUN echo from baz`,
+		"Dockerfile": `FROM busybox
+RUN echo from Dockerfile`,
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer git.Close()
+
+	// Make sure it tries to 'dockerfile' query param value
+	buf, err := sockRequestRaw("POST", "/build?dockerfile=baz&remote="+git.RepoURL, nil, "application/json")
+	if err != nil {
+		t.Fatalf("Build failed: %s\n%q", err, buf)
+	}
+
+	out := string(buf)
+	if !strings.Contains(out, "from baz") {
+		t.Fatalf("Incorrect output: %s", out)
+	}
+
+	logDone("container REST API - check build from git w/F")
+}
+
+func TestBuildApiDoubleDockerfile(t *testing.T) {
+	git, err := fakeGIT("repo", map[string]string{
+		"Dockerfile": `FROM busybox
+RUN echo from Dockerfile`,
+		"dockerfile": `FROM busybox
+RUN echo from dockerfile`,
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer git.Close()
+
+	// Make sure it tries to 'dockerfile' query param value
+	buf, err := sockRequestRaw("POST", "/build?remote="+git.RepoURL, nil, "application/json")
+	if err != nil {
+		t.Fatalf("Build failed: %s", err)
+	}
+
+	out := string(buf)
+	if !strings.Contains(out, "from Dockerfile") {
+		t.Fatalf("Incorrect output: %s", out)
+	}
+
+	logDone("container REST API - check build with two dockerfiles")
+}
+
 func TestBuildApiDockerfileSymlink(t *testing.T) {
 	// Test to make sure we stop people from trying to leave the
 	// build context when specifying a symlink as the path to the dockerfile

integration-cli/docker_cli_build_test.go

@@ -4699,6 +4699,125 @@ func TestBuildRenamedDockerfile(t *testing.T) {
 	logDone("build - rename dockerfile")
 }
 
+func TestBuildFromMixedcaseDockerfile(t *testing.T) {
+	defer deleteImages("test1")
+
+	ctx, err := fakeContext(`FROM busybox
+	RUN echo from dockerfile`,
+		map[string]string{
+			"dockerfile": "FROM busybox\nRUN echo from dockerfile",
+		})
+	defer ctx.Close()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	out, _, err := dockerCmdInDir(t, ctx.Dir, "build", "-t", "test1", ".")
+	if err != nil {
+		t.Fatalf("Failed to build: %s\n%s", out, err)
+	}
+
+	if !strings.Contains(out, "from dockerfile") {
+		t.Fatalf("Missing proper output: %s", out)
+	}
+
+	logDone("build - mixedcase Dockerfile")
+}
+
+func TestBuildWithTwoDockerfiles(t *testing.T) {
+	defer deleteImages("test1")
+
+	ctx, err := fakeContext(`FROM busybox
+RUN echo from Dockerfile`,
+		map[string]string{
+			"dockerfile": "FROM busybox\nRUN echo from dockerfile",
+		})
+	defer ctx.Close()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	out, _, err := dockerCmdInDir(t, ctx.Dir, "build", "-t", "test1", ".")
+	if err != nil {
+		t.Fatalf("Failed to build: %s\n%s", out, err)
+	}
+
+	if !strings.Contains(out, "from Dockerfile") {
+		t.Fatalf("Missing proper output: %s", out)
+	}
+
+	logDone("build - two Dockerfiles")
+}
+
+func TestBuildFromURLWithF(t *testing.T) {
+	defer deleteImages("test1")
+
+	server, err := fakeStorage(map[string]string{"baz": `FROM busybox
+RUN echo from baz
+COPY * /tmp/
+RUN find /tmp/`})
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer server.Close()
+
+	ctx, err := fakeContext(`FROM busybox
+RUN echo from Dockerfile`,
+		map[string]string{})
+	defer ctx.Close()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// Make sure that -f is ignored and that we don't use the Dockerfile
+	// that's in the current dir
+	out, _, err := dockerCmdInDir(t, ctx.Dir, "build", "-f", "baz", "-t", "test1", server.URL+"/baz")
+	if err != nil {
+		t.Fatalf("Failed to build: %s\n%s", out, err)
+	}
+
+	if !strings.Contains(out, "from baz") ||
+		strings.Contains(out, "/tmp/baz") ||
+		!strings.Contains(out, "/tmp/Dockerfile") {
+		t.Fatalf("Missing proper output: %s", out)
+	}
+
+	logDone("build - from URL with -f")
+}
+
+func TestBuildFromStdinWithF(t *testing.T) {
+	defer deleteImages("test1")
+
+	ctx, err := fakeContext(`FROM busybox
+RUN echo from Dockerfile`,
+		map[string]string{})
+	defer ctx.Close()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// Make sure that -f is ignored and that we don't use the Dockerfile
+	// that's in the current dir
+	dockerCommand := exec.Command(dockerBinary, "build", "-f", "baz", "-t", "test1", "-")
+	dockerCommand.Dir = ctx.Dir
+	dockerCommand.Stdin = strings.NewReader(`FROM busybox
+RUN echo from baz
+COPY * /tmp/
+RUN find /tmp/`)
+	out, status, err := runCommandWithOutput(dockerCommand)
+	if err != nil || status != 0 {
+		t.Fatalf("Error building: %s", err)
+	}
+
+	if !strings.Contains(out, "from baz") ||
+		strings.Contains(out, "/tmp/baz") ||
+		!strings.Contains(out, "/tmp/Dockerfile") {
+		t.Fatalf("Missing proper output: %s", out)
+	}
+
+	logDone("build - from stdin with -f")
+}
+
 func TestBuildFromOfficialNames(t *testing.T) {
 	name := "testbuildfromofficial"
 	fromNames := []string{