add attach functionality

public/index.html

@@ -42,6 +42,7 @@
             <tbody id="properties"></tbody>
           </table>
           <div class="hscroll" id="attachments"></div>
+          <div><input type="text" id="attachment" placeholder="URL"><button type="button" onclick="attach()">attach</button></div>
           <table>
             <thead><tr><th>component</th><th>quantity</th><th>description</th></tr></thead>
             <tbody id="components"></tbody>

public/partdb.js

@@ -262,3 +262,29 @@ function update_part()
 	};
 	post.send(JSON.stringify(part));
 }
+
+function attach()
+{
+	const results = document.getElementById('results');
+	if (results.selectedIndex >= 0) {
+		part_id = parseInt(results.options[results.selectedIndex].value);
+	} else {
+		part_id = null;
+		return;
+	}
+	const attachment = document.getElementById('attachment');
+	if (null == attachment.value || 0 == attachment.value.length) {
+		return;
+	}
+	const xhr = new XMLHttpRequest();
+	xhr.open('GET', '/attach?id=' + part_id + "&url=" + encodeURI(attachment.value), true);
+	xhr.onload = function() {
+		clear();
+		search(); // refresh search
+	};
+	xhr.onerror = function() {
+		console.log("part attachment failed");
+	};
+	xhr.send();
+
+}

server.rb

@@ -17,6 +17,7 @@ require 'json'
 require 'sinatra'
 require 'uri'
 require 'net/http'
+require 'cgi'
 
 # allow dumping crashes in browser
 DEBUG = false
@@ -463,3 +464,24 @@ get '/import/lcsc/:lcsc' do
   end
   return 200, "#{part['name']} added"
 end
+
+get '/attach?' do
+  halt 401, "part name or id required" unless params['id'] or params['name']
+  halt 401, "attachement URL required" unless params['url']
+  statement = @db.prepare("SELECT id, name FROM part WHERE id = ? OR name = ?")
+  part = statement.execute(params['id'], params['name']).to_a[0]
+  halt 401, "unknown part" unless part
+  file = CGI.unescape(params['url']).split("/")[-1]
+  dir = PUBLIC + "/" + ATTACHMENTS + "/" + part["name"].gsub("/", "_")
+  path = "#{dir}/#{file}"
+  unless File.file?(path) then
+    uri = URI(params['url'])
+    res = Net::HTTP.get_response(uri)
+    if (res.is_a?(Net::HTTPSuccess)) then
+      Dir.mkdir(dir) unless File.directory?(dir)
+      File.open(path, "wb") do |f|
+        f.write res.body
+      end
+    end
+  end
+end