Range request handling

[mischnic]

I hope this isn't considered out of scope...
This can be tested in the "real world" by browsing to a video file in Safari (didn't work before)

Should these features be implemented as well?

• Handling of multiple ranges (with a multipart response, currently only the first range is used)
• the If-Range header

This change could be considered breaking:

--- a/test/integration.js
+++ b/test/integration.js
@@ -869,9 +869,9 @@ test('set `createReadStream` handler to async function', async t => {

        // eslint-disable-next-line no-undefined
        const url = await getUrl(undefined, {
-               createReadStream: async file => {
+               createReadStream: async (file, opts) => {
                        await sleep(2000);
-                       return fs.createReadStream(file);
+                       return fs.createReadStream(file, opts);
                }
        });

Came up in https://github.com/vercel/serve/issues/447

[codecov]

Codecov Report

Merging #40 into master will not change coverage.
The diff coverage is 100%.

@@          Coverage Diff          @@
##           master    #40   +/-   ##
=====================================
  Coverage     100%   100%           
=====================================
  Files           1      1           
  Lines         289    303   +14     
=====================================
+ Hits          289    303   +14

Impacted Files	Coverage Δ
src/index.js	100% <100%> (ø)	⬆️

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[leo]

What a great PR, thank you!

How is your change to createReadStream a breaking change though? You only added yet another argument for the function call...? 😊

[leo]

By the way, supporting these two would be perfect! ☺️

• Handling of multiple ranges (with a multipart response, currently only the first range is used)
• The If-Range header

Thank you so much!

[leo]

Oh, now I understand why it's a breaking change. Thank you!

Let's add the other two features in a future release, if you want.