GRAIL interview

This is my solution for the GRAIL interview question. It's admittedly a bit over the top for what should have been a short project, but I took the opportunity to learn new stuff including:

• The first Go code I've ever written
• The first time I've used Bazel outside Google's monolithic repository, which has some non-trivial differences
• The first time I've created a gRPC server not using Google internal-only frameworks

Other than that, I've sort-of used gRPC before with Java servers, but Google has a bunch of internal-only frameworks to build them (which is why I decided to learn something new, since there's no RPC framework external to Google I've used before).

The API also follows best practices from https://aip.dev.

Running instructions

Requires Bazel to build. Run the server using the following command:

$ bazel run //cmd/participant-server -- -logtostderr

This starts a REST server listening on port 50051. Note that everything is stored in memory, there is no persistance, so restarting the server will clear everything.

REST API

Participant definition

Participants are represented as JSON objects with the following fields:

Field	Description
name	The resource name of the Participant, not the name of the person. See https://aip.dev/122#fields-representing-resource-names.
givenName	The participant's given name.
familyName	The participant's family name.
birthDate	The participant's date of birth represented as an object with a year, month and day.
phoneNumber	The participant's phone number.
address	The participant's physical address.

POST /v1/participants

Creates a new participant. The body of the request can include a JSON participant but must not set the name field as that will be generated. Returns JSON for the created participant. Not all fields have to be set in case the information is collected gradually.

Example:

$ curl -X POST localhost:50051/v1/participants -d '{"givenName": "Graham", "familyName": "Rogers"}'

GET /v1/participants/{reference}

Gets a participant. Should use the name of a previously created participant otherwise it will 404. Returns a JSON participant.

Example:

$ curl -X GET localhost:50051/v1/participants/AAA-001

PATCH /v1/participants/{reference}

Updates a participant's details. The body of the request should be a JSON participant without the name field. Returns the JSON of the updated participant.

Example:

curl -X PATCH localhost:50051/v1/participants/AAA-001 -d '{"phoneNumber": "01189998819991197253"}'

DELETE /v1/participants/{reference}

Deletes the participant, returning an empty JSON object.

Example:

curl -X DELETE localhost:50051/v1/participants/AAA-001

Running tests

All the tests can be run with bazel test //....