Implement Store::update() interface

imag-store/src/update.rs

@@ -1,5 +1,29 @@
+use std::path::PathBuf;
+use std::ops::DerefMut;
+
 use libimagrt::runtime::Runtime;
+use util::build_toml_header;
+use util::build_entry_path;
 
 pub fn update(rt: &Runtime) {
+    rt.cli()
+        .subcommand_matches("update")
+        .map(|scmd| {
+            rt.store()
+                .retrieve(scmd.value_of("id").map(|id| build_entry_path(rt, id)).unwrap())
+                .map(|mut locked_e| {
+                    let mut e = locked_e.deref_mut();
+
+                    scmd.value_of("content")
+                        .map(|new_content| {
+                            *e.get_content_mut() = String::from(new_content);
+                            debug!("New content set");
+                        });
+
+                    *e.get_header_mut() = build_toml_header(scmd, e.get_header().clone());
+                    debug!("New header set");
+                })
+        });
+
 }