Resolver

Overview

This project served as a service for assets resolving for static files that are being served by a CDN and whose filenames are hashed.

For instance when you reference static files from a template in your favourite framework, you'll probably have a tag like this:

<link type="text/css" media="screen" href="assets.css" rel="stylesheet">

Now, when those files are served by a CDN, and you hashed the filenames, you want to reference those correct, up-to-date files. So the filename assets.css need to be resolved to the correct hashed filename that is served by the CDN.

One way to do this is by using Resolver. It creates a small service which you can query to resolve the filenames ot its hashed equivalent available on the CDN. It does so by storing the key, value combinations of filenames, and hashes in a json file. It exposes several endpoints which can be used to query or update this file.

Hopefully you'll be able to create an equivalent of a template_tag in your chosen framework that enables you to references a function that can query the resolver service. From our example above, this will look something like this, if you were using Django.

<link type="text/css" media="screen" href="{% resolve_assets assets.css %}" rel="stylesheet">

Endpoints

Resolver exposes the following endpoint:

GET /assets/

Response:

// STATUS 200
{
    "asset1": "hash1",
    "asset2": "hash2"
}

POST /assets/

Input:

{
    "asset1": "new_hash1",
    "asset2": "new_hash2"
}

Response:

// STATUS 201
{
    "asset1": "new_hash1",
    "asset2": "new_hash2"
}

Running Resolver

The easiest of running this service is using docker. A binary is also provided in bin/ if you want to run it that way.

$ docker run -it \
    -p 4000:4000 \
    -e "RESOLVER_USER=[user-name]" \
    -e "RESOLVER_KEY=[key]" \
    -v /dir-on-host:/data \
    --name resolver \
    erroneousboat/resolver
    

$ curl -U [user-name]:[password] http://localhost:4000/assets/

Resolver uses http basic authentication, you can create a key at the following site: Htpasswd Generator