Add an OAuth Provider

go get github.com/glincker/theauth-go/v2

import (
    "github.com/glincker/theauth-go/v2"
    "github.com/glincker/theauth-go/v2/provider/github"
    "github.com/glincker/theauth-go/v2/storage/postgres"
)

a, _ := theauth.New(theauth.Config{
    Storage: store,
    BaseURL: "https://myapp.com",
    Providers: []theauth.Provider{
        github.New(github.Config{
            ClientID:     os.Getenv("GITHUB_CLIENT_ID"),
            ClientSecret: os.Getenv("GITHUB_CLIENT_SECRET"),
        }),
    },
})

a, _ := theauth.New(theauth.Config{
    Storage: store,
    BaseURL: "https://myapp.com",
    Providers: []theauth.Provider{
        github.New(github.Config{
            ClientID:     os.Getenv("GITHUB_CLIENT_ID"),
            ClientSecret: os.Getenv("GITHUB_CLIENT_SECRET"),
        }),
        google.New(google.Config{
            ClientID:     os.Getenv("GOOGLE_CLIENT_ID"),
            ClientSecret: os.Getenv("GOOGLE_CLIENT_SECRET"),
        }),
    },
})

GET /auth/providers/{name}/start    -- redirect to provider
GET /auth/providers/{name}/callback -- consume code, issue session

type Provider interface {
    // Name returns the stable registry key, e.g. "github". Routes mount as
    // /auth/providers/{name}/start and /auth/providers/{name}/callback.
    Name() string

    // AuthURL builds the absolute authorization URL. state and
    // codeChallenge are generated by the caller.
    AuthURL(state, codeChallenge, redirectURI string, scopes []string) string

    // ExchangeCode trades an authorization code (and PKCE verifier) for a
    // ProviderToken.
    ExchangeCode(ctx context.Context, code, codeVerifier, redirectURI string) (*ProviderToken, error)

    // UserInfo returns the canonical user profile for the supplied token.
    UserInfo(ctx context.Context, token *ProviderToken) (*ProviderUser, error)
}