airfield

README

go-sfomuseum-airfield

Go package for working with airfield-related activities at SFO Museum (airlines, aircraft, airports).

Documentation

Documentation is incomplete at this time.

A note about "lookups"

As of this writing (October, 2021) most of the code in this package is focused around the code for "looking up" a record using one or more identifiers (for example an ICAO code or a SFO Museum database primary key) and/or to find the "current" instance of a given identifier (it turns out that IATA codes were re-used in the past). In all cases we're trying to resolve a given identifier back to a specific Who's On First ID for that "thing" in time and the code has been broken out in the topic and source specific subpackages.

All of those subpackages implement a generic Lookup interface which looks like this:

type Lookup interface {
	Find(context.Context, string) ([]interface{}, error)
	Append(context.Context, interface{}) error
}

There is an equivalent interface in the go-sfomuseum-architecture package which has all the same concerns as this package but is specific to the architectural elements at SFO. In time it would be best if both packages (go-sfomuseum-architecture and go-sfomuseum-airfield) shared a common "lookup" package/interface but that hasn't happened yet. There were past efforts around this idea in the go-lookup* packages which have now been deprecated. If there is going to be a single common "lookup" interface package then the it will happen in a github.com/sfomuseum/go-lookup/v2 namespace.

Which means that there is a lot of duplicate code to implement functionality around the basic model in order to accomodate the different interfaces because an icao.Aircraft is not the same as a sfomuseum.Aircraft and a sfomuseum.Aircraft won't be the same as a sfomuseum.Airport. Things in the sfomuseum namespace tend to be more alike than not but there are always going to be edge-cases so the decision has been to suffer duplicate code (in different subpackages) rather than trying to shoehorn different classes of "things" in to a single data structure.

One alternative approach would be to adopt the GoCloud As model but there is a sufficient level of indirection that I haven't completely wrapped my head around so it's still just an idea for now.

It's not great. It's just what we're doing today. The goal right now is to expect a certain amount of "rinse and repeat" in the short term while aiming to make each cycle shorter than the last.

Data storage for "lookups"

The default data storage layer for lookup is an in-memory sync.Map. This works well for most cases and enforces a degree of moderation around the size of lookup tables. Another approach would be to use the philippgille/gokv package (or equivalent) which is a simple interface with multiple storage backends. TBD..

See also

• https://github.com/sfomuseum-data/sfomuseum-data-aircraft
• https://github.com/sfomuseum-data/sfomuseum-data-enterprise
• https://github.com/sfomuseum-data/sfomuseum-data-whosonfirst

Documentation

Overview

package airfield provides methods for working with airfield-related activities at SFO Museum (airlines, aircraft, airports).

Index

• func RegisterLookup(ctx context.Context, scheme string, init_func LookupInitializationFunc) error
• type Lookup
  • func NewLookup(ctx context.Context, uri string) (Lookup, error)
• type LookupInitializationFunc

Functions

func RegisterLookup

func RegisterLookup(ctx context.Context, scheme string, init_func LookupInitializationFunc) error

Types

type Lookup

type Lookup interface {
	Find(context.Context, string) ([]interface{}, error)
	Append(context.Context, interface{}) error
}

func NewLookup

func NewLookup(ctx context.Context, uri string) (Lookup, error)

type LookupInitializationFunc

type LookupInitializationFunc func(ctx context.Context, uri string) (Lookup, error)