# The documentation for aurelia-http-client is non-existent

**URL:** <https://discourse.aurelia.io/t/the-documentation-for-aurelia-http-client-is-non-existent/5511>\
**Category:** Best Practices\
**Created:** [August 8, 2024, 12:07pm UTC](https://discourse.aurelia.io/t/the-documentation-for-aurelia-http-client-is-non-existent/5511 "2024-08-08T12:07:22Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![mberdev](https://yyz1.discourse-cdn.com/flex027/user_avatar/discourse.aurelia.io/mberdev/32/2529_2.png) [@mberdev](https://discourse.aurelia.io/u/mberdev)\
**Post date:** [August 8, 2024, 12:07pm UTC](https://discourse.aurelia.io/t/the-documentation-for-aurelia-http-client-is-non-existent/5511/1 "2024-08-08T12:07:22Z")

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My legacy project uses the `HttpClient` class of `aurelia-http-client`.

I find myself trying to understand how to use the `get`, `post`, etc. methods for **error handling**.  
I cannot find the answer anywhere. For example, I don’t know if I should use `try/catch`. the documentation does not have any elaborate example. (apart for saying that interceptors can be used, but we don’t do that).

> **[HTTP Services | Aurelia](https://aurelia.io/docs/plugins/http-services/)**
>
> Usually JavaScript applications need to get their data from or communicate with various web services. In this article we'll take a look at the options Aurelia makes available to you.

I instinctively believed that it might work the same way as the basic `fetch` API, but it seems I’m wrong. For example the errors caught in the try/catch seem to have a `.response` field?

**All I need is an actual code snippet showing:**

- how to catch _all_ the errors ,
- and then _filtering on error status_.,
- and then looking at _what the error object contains_

The snippet should be **strongly-typed.** I want to know what kind of objects I’m dealing with.

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**Author:** ![bigopon](https://yyz1.discourse-cdn.com/flex027/user_avatar/discourse.aurelia.io/bigopon/32/18_2.png) [@bigopon](https://discourse.aurelia.io/u/bigopon)\
**Post date:** [August 8, 2024, 1:12pm UTC](https://discourse.aurelia.io/t/the-documentation-for-aurelia-http-client-is-non-existent/5511/2 "2024-08-08T13:12:12Z")

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Indeed, v1 doc is quite bad in a few areas. Thanks for the note @mberdev

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<div class="post-metadata">

**Author:** ![mberdev](https://yyz1.discourse-cdn.com/flex027/user_avatar/discourse.aurelia.io/mberdev/32/2529_2.png) [@mberdev](https://discourse.aurelia.io/u/mberdev)\
**Post date:** [August 8, 2024, 2:12pm UTC](https://discourse.aurelia.io/t/the-documentation-for-aurelia-http-client-is-non-existent/5511/3 "2024-08-08T14:12:01Z")

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I didn’t even know this was v1. I thought our project was using v2…

Since I couldn’t tell if your reply was sarcastic (either way it didn’t shed any light on my problem), I spent some time writing the snippet myself.

===========================

The main difference between Aurelia’s HttpClient and the fetch api is that **in Aurelia failures will ALWAYS throw an error.**  
I.e. in Aurelia there is no distinction between (a) _“failed because network error”_ (which would throw in `fetch`), and (b) _“failed because some more benign problem such as bad request”_ (which would _not_ throw in `fetch` and would require to check the status code).

Aurelia makes it simpler.

**Scenario 1 : We only want to process a success (any success) or an error (any error)**

_We only need the payload (i.e. content) of a success, and only want to catch the error code or message._

```
import {HttpClient, HttpResponseMessage} from "aurelia-http-client";

export interface MyResultType {
    myValue: number;
}

....

try {
    const result:MyResultType = (await myHttpClient.get("http://my-get-url")).content;
    console.log(result.myValue);
} catch (e) {
    const err = e as ErrorHttpResponseMessage;
    console.error(err?.message ?? "An error occurred");
    console.error(err?.statusCode);

} finally {
   console.log ("all done!");
}

```

Notice the **.content** after the get.

**Scenario 2 : We want to process a success (any success) or a SPECIFIC error**

We only need the payload (i.e. content) of a success, but this time we want to study the errors.

```
try {
    const result:MyResultType = (await myHttpClient.get("http://my-get-url")).content;
    console.log(result.myValue);
} catch (e) {
    const err = e as ErrorHttpResponseMessage;

    switch(err.statusCode) {
           case HttpResponseStatus.BAD_REQUEST: 
                console.error(err.response); // <-- if we assume your response is a raw string containing only the error message
                 console.log(err?.message ?? "Bad request fallback"); // <-- if we assume you made it a message
                 console.error(((err.content) as MyElaborateErrorObject).myElaborateErrorField); // <-- if your error contains an object
                 break;
          default:
                 console.log(err?.message ?? "An error occurred");
    }
    console.log(err.statusCode);
} finally {
   console.log ("all done!");
}

```

Notice how the **.content** was still there

**Scenario 3 : We want to fully process the success**

We only need the payload (i.e. content) of a success, but this time we want to study the errors.

```
try {
    const response:HttpResponseMessage= await myHttpClient.get("http://my-get-url");
    switch(response.statusCode) {
           case HttpResponseStatus.OK:
                      ...
           case HttpResponseStatus.NO_CONTENT:
                      ...  
     }
    // Maybe you also want to study the success response even more!
    if (response.headers.get("my-header")) === "something") {
            ...
    }
} catch (e) {
      .... // Same as before
}

```

Notice how the **.content** is no longer there

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<div class="post-metadata">

**Author:** ![bigopon](https://yyz1.discourse-cdn.com/flex027/user_avatar/discourse.aurelia.io/bigopon/32/18_2.png) [@bigopon](https://discourse.aurelia.io/u/bigopon)\
**Post date:** [August 8, 2024, 2:35pm UTC](https://discourse.aurelia.io/t/the-documentation-for-aurelia-http-client-is-non-existent/5511/4 "2024-08-08T14:35:08Z")

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I wasn’t sarcastic, I just didn’t have anything more to say as I didn’t want to promise something I may not be able to do. (It’s just I’m a bit tight on the time budget, and I wanted to say I’ll look into it and add more typings or something to help).