Idea #9005
Updated by Tom Clegg almost 8 years ago
h2. Background
As an example, keep-web currently
* gets an arvadosclient.ArvadosClient from an arvadosclient.ClientPool
* configures it with the current token
* passes it to keepclient.MakeKeepClient() in order to get a keepclient.Client
(The public APIs for creating a keepclient.Client all involve passing in an arvadosclient.ArvadosClient, so we can't just make a pool of keepclient.Clients and assume they won't leak credentials across requests.)
At this point, keepclient.MakeKeepClient() creates a new http.Client object. This means
* Consecutive keep-web requests cannot reuse http connections to keep services
* (Currently) the HTTP connections to keep services are left open anyway, because we don't tell the http.Client that we won't be reusing it
In general, sharing an http.Client across requests is beneficial because it reduces TCP and TLS handshaking.
h2. Proposed improvements
MakeKeepClient should use the http.Client handed to it in the arvadosclient.ArvadosClient object. The Client field is already exported so the caller can override it later if desired. When an arvadosclient.ClientPool is used, this change alone should reduce the proliferation of http.Client objects significantly.
Also, arvadosclient.MakeArvadosClient should reuse the same two http.Client objects for all new ArvadosClient objects -- e.g., arvadosclient.DefaultHTTPClient when ApiInsecure is false, arvadosclient.DefaultInsecureHTTPClient when true. The caller can override it later if desired.
arvadosclient.DefaultHTTPClient should default to http.DefaultClient.