Correspondence Map

A geographic visualization of correspondence between abolitionists in the 19th century

Project Set Up

This project consists of two parts:

1. A parser for downloading data from the DPLA API
2. A map that visualizes the data using LeafletJS

Parser

1. In order to use the parser you will need to install NodeJS.

2. After installing Node, you will need to install the project dependencies

   1. Open a command prompt window and navigate to the parser folder where the project is located
      1. Type cd [directory where you saved the project]
   2. run npm install. This will create a folder called node_modules and will install the libraries you need into it.

3. Create a file using notepad or another plain text editor called config.json in the parser folder with the text below. Replace [API Key] with your DPLA API key.

   {
     "api_key": "[API Key]"
   }
   

4. From the command prompt window run node get-data.js. This will download the data into a file called letters.csv

Setting up the map

Before running the map you will need to save the letters.csv file you created with the parser into the main repository folder. The repo includes a sample letters file named letters-sample.csv. To use this data set simply rename this file to letters.csv. If you are using your own data, the map assumes that you have a file named letters.csv with at least the following columns:

Field	Column Name
Sender	sender
Recipient	recipient
Title	title
Link	link
Date	date
Place	place
Sent Location	sentLocation
Received Location	receivedLocation
Sender Latitude	senderLat
Sender Longitude	senderLng
Receiver Latitude	receiverLat
Receiver Longitude	receiverLng

Remote web server

If you have a website with FTP access, the easiest thing to do is copy all the files in this repository to your web server in a folder called something like map. The map should then be available on your website at that folder i.e. http://www.yourdomain.com/map

Local web server

There are a number of ways to run a local web server, one of the easiest with Node is to use the node-server module.

1. Open a command line and navigate to the folder where the project is located.
2. Run npm install -g jitsu
3. Run jitsu install http-server
4. Run node http-server/bin/http-server

There will now be a server running by default on port 8080. To visit the map open a browser and go to http://localhost:8080

To stop the server you will hit Ctrl-C. To start the server again, you don't need to download it again, just run node http-server/bin/http-server

Code Organization

Parser

All the code for the parser is contained in the parser folder. At present this is a single file named get-data.js, a configuration file named config.json, and a package.json for node installation.

Map

The core code of the map is organized into four different files, all of which can be found in the js folder:

• controls.js contains functions that handle the time line slider and filters.
• data.js contains functions that load and handle the initial formatting of the CSV file.
• map.js contains all the code which loads and displays the map layers, including filtering the layers in response to the controls.
• sidebar.js contains the code which displays detailed letter information in the sidebar when a line or point is clicked.