During doc fetch, share each example to the Go playground,
then add a link to that shared example alongside the code.

Fixes golang/go#36865

Change-Id: I541774af5f29e0bdbb9bd812496cc6e4fd39fcb6
Reviewed-on: https://team-review.git.corp.google.com/c/golang/discovery/+/715584
Reviewed-by: Julie Qiu <julieqiu@google.com>

…ang.org/share

This change adds a /play handler that mirrors requests
to play.golang.org/share which is used in implementing playground
integration in the frontend. This change also adds a test that
includes a mock server using net/httptest to check for proper
status codes.

Updates golang/go#36865

Change-Id: Ia3e902808534189ada747b270fed908e766c224b
Reviewed-on: https://go-review.googlesource.com/c/pkgsite/+/241164
Reviewed-by: Julie Qiu <julie@golang.org>
Reviewed-by: Jonathan Amsterdam <jba@google.com>

This commit modifies the codeHTML function to use *doc.Example
instead of a *doc.Example.Code so that we can have access to
*doc.Example.Play whenever the example is executable. This is important so that the imports are visible in the
example documentation. If the example doesn't include a executable editor,
it will default to rendering *doc.Example.Code. Also, this commit modifies the HTML template
to include a play button for the playground integration, which will be
displayed once all of the play button functionality is incorporated.
This commit also adds an experiment flag to enable the feature by
passing in context to the render function

For golang/go#36865

Change-Id: If2ef0d128fdd791617aad5dd8eb8a08c90e9ae72
Reviewed-on: https://go-review.googlesource.com/c/pkgsite/+/240685
Reviewed-by: Jonathan Amsterdam <jba@google.com>

The experiment variable for executable examples was describing the
description of the variable rather than the name constant. This CL
changes it to the name constant.

For golang/go#36865

Change-Id: I84c3fcf8147c2c3964c262037ff2340f2ca0f39a
Reviewed-on: https://go-review.googlesource.com/c/pkgsite/+/243037
Reviewed-by: Jonathan Amsterdam <jba@google.com>
Reviewed-by: Julie Qiu <julie@golang.org>

…r executable examples

This CL adds the HTML changes for the new play button, and error message for the playground integration. Corresponding experiment/feature flag is included.

This change also adds example_test testdata for tests that verify executable and non executable examples.

For golang/go#36865

Change-Id: I3b0339f61c2e46881681cc271252499142785000
Reviewed-on: https://go-review.googlesource.com/c/pkgsite/+/243222
Reviewed-by: Julie Qiu <julie@golang.org>

This CL adds the CSS styling for the new playground examples. It is
currently under a feature flag, so the CL won't make any visible changes to the
website yet.

Without error: https://i.imgur.com/OK4V0sU.png
With error: https://i.imgur.com/sfqhZub.png

For golang/go#36865

Change-Id: I8d0e2aeeb4076bb863d36887bfe8cb0d791a1f25
Reviewed-on: https://go-review.googlesource.com/c/pkgsite/+/243638
Reviewed-by: Andrew Bonventre <andybons@golang.org>

This CL reverts the change for a "HideButtons" field in a package
example struct. Instead of using a feature flag that we turn off and on
for displaying the new Playground buttons, we will just replace the
`display: none;` property back to `display: flex` in a future commit.

For golang/go#36865

Change-Id: Iee29c431c22dc263bda8a812dfc148fd62d77f84
Reviewed-on: https://go-review.googlesource.com/c/pkgsite/+/244763
Reviewed-by: Miguel Acero <acero@google.com>

fetchPlayUrl creates a request to golang.org/share during the fetch process which we do not want since it would make too many requests. We no longer need this code since we are generating the playUrl in the client side through a button in the frontend. The current implementation has tests for modules with examples and replaces the playlinks.

This commit also updates the tests to reflect the current playground implementation.

For golang/go#36865

Change-Id: Ie590538db2dcdb94d5aa2cdac9c72c3522b7a565
Reviewed-on: https://go-review.googlesource.com/c/pkgsite/+/241259
Reviewed-by: Julie Qiu <julie@golang.org>

This change adds a boolean "replay" flag in the existing playground test for the /share endpoint. When enabled, the test will make a request to play.golang.org instead of a mock httptest server.

For golang/go#36865

Change-Id: I26bb79d21500edbc128ce46e19bed493585a3e31
Reviewed-on: https://go-review.googlesource.com/c/pkgsite/+/245378
Reviewed-by: Julie Qiu <julie@golang.org>
Reviewed-by: Jonathan Amsterdam <jba@google.com>

…yground

This CL implements a "play button" for each example in a given package
that redirects to play.golang.org.

This code is based on https://golang.org/lib/godoc/playground.js, it was
modified to remove the dependence on jquery and bootstrap, as well as
removing DOM creation to prevent jittering of the website.

Example behavior: https://i.imgur.com/NcGO3kx.gif

For golang/go#36865

Change-Id: Ic17ebd038561ef4dabbd139f6fa2e378968b01a1
Reviewed-on: https://go-review.googlesource.com/c/pkgsite/+/243699
Reviewed-by: Andrew Bonventre <andybons@golang.org>

A metric is added for everytime a request is sent to play.golang.org.
The request status code will be used and is useful to have better
visibility on how many users click the new playground "play" button.

For golang/go#36865

Change-Id: I243efe5b3d8724fa6bdd60d332e2932925ffe094
Reviewed-on: https://go-review.googlesource.com/c/pkgsite/+/245898
Reviewed-by: Jonathan Amsterdam <jba@google.com>

The changes here will not appear until the display: none; experiment
flag is removed

If a playground example doesn't have an output and is accompanied by
another example right below, currently there is no margin that separates
the dropdown div and code input div above it. This change adds a
margin-top to the dropdown.

i.e: Non-executable example with no output
https://pkg.go.dev/github.com/prometheus/client_golang/prometheus?tab=doc#example-Timer
before: https://i.imgur.com/SpCNKQj.png
after:  https://i.imgur.com/iIr6ThE.png

If a playground example doesn't have an output, currently there is no
margin that separates the button and the code input div above it. This
change adds a margin-top on the button container.

i.e: Executable example with no output.
https://pkg.go.dev/cloud.google.com/go?tab=doc#example-package-ApplicationDefaultCredentials
before: https://i.imgur.com/yFMkKrt.png
after:  https://i.imgur.com/UkmqiHJ.png

The reason the margin-top in the button container doesn't add onto the
margin-bottom in an example with an output is because of margin
collapsing that occurs between margin top and bottom properties. This is
also true for the dropdown margin-top when the div above the dropdown is
not the code input div.

i.e: Executable example with output the before and after will remain the
same https://i.imgur.com/hSzjvBn.png

i.e: Dropdown with paragraph element above the before and after will
remain the same https://i.imgur.com/niyfG7B.png

For golang/go#36865

Change-Id: I5a271cb6cb899fcec6cbd22920e885c69c20b52b
Reviewed-on: https://go-review.googlesource.com/c/pkgsite/+/247401
Reviewed-by: Julie Qiu <julie@golang.org>

This change replaces display: none; with display: flex; to enable
executable examples in in the documentation page. The HTML changes used
for this CSS change requires the executable-examples feature flag.

Updates golang/go#36865

Change-Id: I2cb62438663ecbfbccfe1f5b4b6b1e2dbe3e3916
Reviewed-on: https://go-review.googlesource.com/c/pkgsite/+/253599
Reviewed-by: Julie Qiu <julie@golang.org>