I just started using jcabi's fluent http client and I feel like I am missing some general error handling routines (I believe each jcabi-http user faces it).
So, for a start there's always IOException when I use fetch() or json().readObject() and my first attempt looks like this:
try {
return new JdkRequest("http://localhost")
.uri()
...
.back()
.method(Request.GET)
.fetch()
.as(JacksonResponse.class)
.json().readObject()
...;
} catch (IOException e) {
throw new RuntimeException(e);
}
Next, when response's status in not 200 OK, then json().readObject() fails with the error that "this is not a json you gave me". So I add status check:
try {
return new JdkRequest("http://localhost")
...
.fetch()
.as(RestResponse.class)
.assertStatus(HttpURLConnection.HTTP_OK)
.as(JacksonResponse.class)
...;
} catch (IOException e) {
throw new RuntimeException(e);
}
With this when status is not 200 OK I receive AssertionError, which I have to handle to give it some business meaning:
try {
return new JdkRequest("http://localhost")
...
.fetch()
.as(RestResponse.class)
.assertStatus(HttpURLConnection.HTTP_OK)
.as(JacksonResponse.class)
...;
} catch (IOException ex) {
throw new RuntimeException(ex);
}
} catch (AssertionError error) {
wrapBusiness(error);
}
Next when I want to get different behavior for 401, 403, 404 of 5xx statuses, then my code will transform into something like this:
try {
val response = new JdkRequest("http://localhost")
...
.fetch()
.as(RestResponse.class);
HttpStatusHandlers.of(response.status()).handle();
return response
.as(JacksonResponse.class)
...;
} catch (IOException ex) {
throw new RuntimeException(ex);
}
This "code evolution" looks like a common pattern and I am reinventing the wheel.
Maybe there's an already implemented (or described) solution (or a Wire.class)?
You are doing everything correctly.
IOExceptionwill happen if there is some network problem,AssertionErroris flying outassert*()methods. The rest is up to your business logic.A few examples: