Add some prerequisites

src/resources/mod.rs

@@ -1,3 +1,5 @@
+use std::borrow::Cow;
+
 pub trait Resource {
   fn get_type(&self) -> &str;
   fn get_value(&self) -> &str;
@@ -11,3 +13,12 @@ impl<'a> Resource for UserResource<'a> {
   fn get_type(&self) -> &str { "user" }
   fn get_value(&self) -> &str { self.name }
 }
+
+pub struct DirResource<'a> {
+  pub path: Cow<'a, str>
+}
+
+impl<'a> Resource for DirResource<'a> {
+  fn get_type(&self) -> &str { "dir" }
+  fn get_value(&self) -> &str { &*self.path }
+}

src/symbols/dir.rs

@@ -0,0 +1,49 @@
+use std::borrow::Cow;
+use std::error::Error;
+use std::fmt;
+use std::fs;
+use std::io;
+use std::io::{Read, Write};
+use std::ops::Deref;
+use std::path::Path;
+
+use symbols::Symbol;
+
+pub struct Dir<D> where D: AsRef<str> + fmt::Display {
+  path: D
+}
+
+impl<D> Dir<D> where D: AsRef<str> + fmt::Display {
+  pub fn new(path: D) -> Self {
+    Dir { path: path }
+  }
+}
+
+impl<D> Symbol for Dir<D> where D: AsRef<str> + fmt::Display {
+  fn target_reached(&self) -> Result<bool, Box<Error>> {
+    let metadata = fs::metadata(self.path.as_ref());
+    // Check if dir exists
+    if let Err(e) = metadata {
+      return if e.kind() == io::ErrorKind::NotFound {
+        Ok(false)
+      } else {
+        Err(Box::new(e))
+      };
+    }
+    if metadata.unwrap().is_dir() {
+      Ok(true)
+    } else {
+      Err(Box::new(io::Error::new(io::ErrorKind::AlreadyExists, "Could not create a directory, non-directory file exists")))
+    }
+  }
+
+  fn execute(&self) -> Result<(), Box<Error>> {
+    fs::create_dir_all(self.path.as_ref()).map_err(|e| Box::new(e) as Box<Error>)
+  }
+}
+
+impl<D> fmt::Display for Dir<D> where D: AsRef<str> + fmt::Display {
+  fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error>{
+    write!(f, "Dir {}", self.path)
+  }
+}

src/symbols/file.rs

@@ -8,6 +8,7 @@ use std::ops::Deref;
 use std::path::Path;
 
 use symbols::Symbol;
+use resources::{DirResource, Resource};
 
 pub struct File<C, D> where C: Deref<Target=str>, D: AsRef<str> + fmt::Display {
   path: D,
@@ -52,6 +53,11 @@ impl<C, D> Symbol for File<C, D> where C: Deref<Target=str>, D: AsRef<str> + fmt
     try!(file.write_all(self.content.as_bytes()));
     Ok(())
   }
+
+  fn get_prerequisites(&self) -> Vec<Box<Resource>> {
+    vec![
+      Box::new(DirResource { path: String::from(Path::new(self.path.as_ref()).parent().unwrap().to_string_lossy()).into() }) ]
+  }
 }
 
 impl<C, D> fmt::Display for File<C, D> where C: Deref<Target=str>, D: AsRef<str> + fmt::Display {

src/symbols/mod.rs

@@ -1,12 +1,17 @@
 use std::borrow::Cow;
 use std::error::Error;
 use std::fmt::Display;
+use resources::Resource;
 
 pub trait Symbol: Display {
   fn target_reached(&self) -> Result<bool, Box<Error>>;
   fn execute(&self) -> Result<(), Box<Error>>;
+  fn get_prerequisites(&self) -> Vec<Box<Resource>> {
+    vec![]
+  }
 }
 
+pub mod dir;
 pub mod file;
 pub mod git;
 pub mod npm;

src/symbols/nginx/server.rs

@@ -6,6 +6,7 @@ use std::ops::Deref;
 use command_runner::CommandRunner;
 use symbols::Symbol;
 use symbols::file::File as FileSymbol;
+use resources::Resource;
 
 #[derive(Debug)]
 pub enum NginxServerError<E: Error> {
@@ -99,6 +100,10 @@ impl<'a, C> Symbol for NginxServer<'a, C> where C: Deref<Target=str> {
     try!(self.command_runner.run_with_args("systemctl", &["reload-or-restart", "nginx"]));
     Ok(())
   }
+
+  fn get_prerequisites(&self) -> Vec<Box<Resource>> {
+    self.file.get_prerequisites()
+  }
 }
 
 impl<'a, C> fmt::Display for NginxServer<'a, C> where C: Deref<Target=str> {

src/symbols/systemd/node_js_user_service.rs

@@ -12,6 +12,7 @@ use std::ops::Deref;
 use command_runner::CommandRunner;
 use symbols::Symbol;
 use symbols::file::File as FileSymbol;
+use resources::Resource;
 
 #[derive(Debug)]
 pub enum NodeJsSystemdUserServiceError<E: Error> {
@@ -146,6 +147,10 @@ impl<'a, P, C> Symbol for NodeJsSystemdUserService<'a, P, C> where P: AsRef<str>
 
     Ok(())
   }
+
+  fn get_prerequisites(&self) -> Vec<Box<Resource>> {
+    self.file.get_prerequisites()
+  }
 }
 
 impl<'a, P, C> fmt::Display for NodeJsSystemdUserService<'a, P, C> where P: AsRef<str> + fmt::Display, C: Deref<Target=str> {