add /admin/schema endpoint

[abhimanyusinghgaur]

This change is 

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[pawanrawal]

Reviewable status: 0 of 7 files reviewed, 5 unresolved discussions (waiting on @abhimanyusinghgaur, @manishrjain, @MichaelJCompton, and @pawanrawal)

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dgraph/cmd/alpha/http.go, line 570 at r4 (raw file):

	}

	res := map[string]interface{}{}

create a small function for this and reuse below.

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graphql/e2e/common/common.go, line 696 at r3 (raw file):

	}

	var addResult struct {

Also check that Errors should be of length 0.

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graphql/web/http.go, line 110 at r3 (raw file):

	if r.URL.Path == "/admin/schema" {
		handleAdminSchemaRequest(ctx, w, r, gh)

return here, then you don't need the else below.

[pawanrawal]

Reviewed 2 of 4 files at r1, 2 of 4 files at r2, 3 of 3 files at r4.
Reviewable status: 5 of 7 files reviewed, 5 unresolved discussions (waiting on @abhimanyusinghgaur, @manishrjain, @MichaelJCompton, and @pawanrawal)

[abhimanyusinghgaur]

Reviewable status: 5 of 7 files reviewed, 5 unresolved discussions (waiting on @golangcibot, @manishrjain, @MichaelJCompton, and @pawanrawal)

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dgraph/cmd/alpha/http.go, line 570 at r4 (raw file):

Previously, pawanrawal (Pawan Rawal) wrote…

create a small function for this and reuse below.

Done.

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graphql/e2e/common/common.go, line 696 at r3 (raw file):

Previously, pawanrawal (Pawan Rawal) wrote…

Also check that Errors should be of length 0.

Done.

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graphql/web/http.go, line 196 at r1 (raw file):

Previously, golangcibot (Bot from GolangCI) wrote…

context.Context should be the first parameter of a function (from golint)

Done.

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graphql/web/http.go, line 196 at r2 (raw file):

Previously, golangcibot (Bot from GolangCI) wrote…

line is 112 characters (from lll)

Done.

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graphql/web/http.go, line 110 at r3 (raw file):

Previously, pawanrawal (Pawan Rawal) wrote…

return here, then you don't need the else below.

Done.