Why does HashiCorp seem to refer to upstream / downstream as the opposite of everything else I've read?

Nomad
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Everywhere I’ve read in the docs seem to use these terms to mean the opposite of what I’ve seen anywhere else.

For example, HashiCorp calls a database “upstream”. I always understood that to be downstream:

frontend -> API -> database

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An upstream is a backend server. See for example nginx, which defines the backends as upstreams:

http://nginx.org/en/docs/http/ngx_http_upstream_module.html

You are fetching information/ data, so it streams up the vertical workflow.

Whatever you read, HashiCorp is not the only company talking this way about upstreams. :wink:

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Ah, so the stream isn’t the representation of the request, but of the response?

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I think that’s the way it is. :slight_smile:

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I am assuming this is related to the connect integration?

I always like to use images such as these https://dpzbhybb2pdcj.cloudfront.net/posta2/v-5/Figures/envoy-internals-high-level.png to keep upstream and downstream confusion to a minimum.

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Thanks! The image does help, but I still say that naming is confusing since it’s the opposite of the definition of the word: https://www.merriam-webster.com/dictionary/upstream

Upstream normally means where the water is coming from.

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The definition used for upstream and downstream is coming from Envoy, so that terminology shows itself inside the connect stanza too.

https://www.envoyproxy.io/docs/envoy/latest/intro/arch_overview/intro/terminology

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