diff --git a/lib/ex_docker_build/dockerfile_parser.ex b/lib/ex_docker_build/dockerfile_parser.ex
index 62273cb..404998b 100644
--- a/lib/ex_docker_build/dockerfile_parser.ex
+++ b/lib/ex_docker_build/dockerfile_parser.ex
@@ -3,10 +3,17 @@ defmodule ExDockerBuild.DockerfileParser do
   @continuation ~r/^.*\\\s*$/
   @instruction ~r/^\s*(\w+)\s+(.*)$/
 
-  @spec parse!(Path.t()) :: list(String.t()) | no_return()
-  def parse!(path) do
+  @spec parse!(Path.t() | String.t()) :: list(String.t()) | no_return()
+  def parse!(path_or_content) do
+    content =
+      if File.exists?(path_or_content) do
+        File.read!(path_or_content)
+      else
+        path_or_content
+      end
+
     {parsed_lines, _} =
-      File.read!(path)
+      content
       |> String.split("\n")
       |> Enum.reduce({[], false}, fn line, {acc, continuation?} ->
         case parse_line(line, continuation?) do
diff --git a/test/dockerfile_parser_test.exs b/test/dockerfile_parser_test.exs
index 9107b4e..393fca5 100644
--- a/test/dockerfile_parser_test.exs
+++ b/test/dockerfile_parser_test.exs
@@ -58,4 +58,22 @@ defmodule ExDockerBuild.DockerfileParserTest do
               "set -xe  && REBAR3_DOWNLOAD_URL=\"https://github.com/erlang/rebar3/archive/${REBAR3_VERSION}.tar.gz\"  && REBAR3_DOWNLOAD_SHA256=\"40b3c85440f3235c7b149578d0211bdf57d1c66390f888bb771704f8abc71033\"  && mkdir -p /usr/src/rebar3-src  && curl -fSL -o rebar3-src.tar.gz \"$REBAR3_DOWNLOAD_URL\"  && echo \"$REBAR3_DOWNLOAD_SHA256 rebar3-src.tar.gz\" | sha256sum -c -  && tar -xzf rebar3-src.tar.gz -C /usr/src/rebar3-src --strip-components=1  && rm rebar3-src.tar.gz  && cd /usr/src/rebar3-src  && HOME=$PWD ./bootstrap  && install -v ./rebar3 /usr/local/bin/  && rm -rf /usr/src/rebar3-src"}
            ]
   end
+
+  test "parses file content instead of a file" do
+    content = """
+    FROM elixir:1.7.3
+    VOLUME /Users/kiro/test:/data
+    RUN echo "hello-world!!!!" > /data/myfile.txt
+    CMD ["cat", "/data/myfile.txt"]
+    """
+
+    result = Parser.parse!(content)
+
+    assert result == [
+             {"FROM", "elixir:1.7.3"},
+             {"VOLUME", "/Users/kiro/test:/data"},
+             {"RUN", "echo \"hello-world!!!!\" > /data/myfile.txt"},
+             {"CMD", "[\"cat\", \"/data/myfile.txt\"]"}
+           ]
+  end
 end