add file ops

Signed-off-by: Tony Worm <tony@hofstadter.io>

stdlib/file/file.cue

@@ -0,0 +1,72 @@
+package file
+
+import (
+	"strings"
+	"dagger.io/dagger"
+)
+
+#Create: {
+	filename: !=""
+  permissions: int | *0o644
+	contents: string | bytes
+
+	#compute: [
+		dagger.#WriteFile & { dest: filename, content: contents, mode: permissions}
+	]
+}
+
+#Append: {
+	filename: !=""
+  permissions: int | *0o644
+	contents: string | bytes
+	from: dagger.#Artifact
+
+	orig: (#read & { path: filename, "from": from }).data
+
+	#compute: [
+		dagger.#WriteFile & { dest: filename, content: "\(orig)\(contents)", mode: permissions}
+	]
+}
+
+#Read: {
+	filename: !=""
+	from: dagger.#Artifact
+	contents: (#read & { path: filename, "from": from }).data
+}
+
+#read: {
+	path: !=""
+	from: dagger.#Artifact
+	data: {
+		string
+		#compute: [
+			dagger.#Load & {"from": from},
+			dagger.#Export & { source: path }
+		]
+	}
+}
+
+#Glob: {
+	glob: !=""
+	filenames: [...string]
+	from: dagger.#Artifact
+	files: (_#glob & { "glob": glob, "from": from }).data
+	// trim suffix because ls always ends with newline
+	filenames: strings.Split(strings.TrimSuffix(files, "\n"), "\n")
+}
+
+_#glob: {
+	glob: !=""
+	from: dagger.#Artifact
+	data: {
+		string
+		_tmppath: "/tmp/ls.out"
+		#compute: [
+			dagger.#Load & {"from": from},
+			dagger.#Exec & {
+				args: ["sh", "-c", "ls \(glob) > \(_tmppath)"]
+			},
+			dagger.#Export & { source: _tmppath }
+		]
+	}
+}