Add Fetch Data From An Endpoint In SQL as a Postgres TIL

postgres/fetch-data-from-an-endpoint-in-sql.md

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+# Fetch Data From An Endpoint In SQL
+
+The [`pgsql-http` extension](https://github.com/pramsey/pgsql-http) provides a
+variety of functions for allowing PostgreSQL to act as an HTTP client. This is
+a bit unorthodox and may not be a good idea in production systems. That said,
+it is cool that it is possible. Let's look at an example of it.
+
+First, I've installed the extension on the Docker container running my local
+Postgres server.
+
+```bash
+$ docker exec -it still-postgres-1 bash
+
+$ apt-get update
+
+$ apt-get install postgres-16-http # I'm running Postgres v16
+
+$ exit
+```
+
+Then I'll connect to a `psql` session in that container for the `postgres` database.
+
+```bash
+$ docker exec still-postgres-1 psql -U postgres -d postgres
+```
+
+Then I enable the extension.
+
+```sql
+> create extension if not exists http;
+CREATE EXTENSION
+```
+
+Now I can point a PostgreSQL statement at a live endpoint like
+[https://httpbun.com/ip](https://httpbun.com/ip) which will respond with a
+chunk of JSON including the IP address for that project's server. I do this
+using `http_get` which makes a `GET` request to the given endpoint. The body is
+included in the result set.
+
+```bash
+> select content from http_get('http://httpbun.com/ip');
+           content
+-----------------------------
+ {                          +
+   "origin": "73.75.236.101"+
+ }                          +
+
+(1 row)
+```