http/get_simple/julia/server/server.jl

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# to you under the Apache License, Version 2.0 (the
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# with the License.  You may obtain a copy of the License at
#
#   http://www.apache.org/licenses/LICENSE-2.0
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using Arrow, HTTP, Random, Tables

function randint_nullable(n::Integer)
    v = Vector{Union{Missing, Int}}(undef, n)
    rand!(v, Int)
    return v
end

function get_stream(::HTTP.Request)
    total_records = 100_000_000
    batch_len = 4096
    stream = Tables.partitioner(Iterators.partition(1:total_records, batch_len)) do indices
        nrows = length(indices)
        return (
            a = randint_nullable(nrows),
            b = randint_nullable(nrows),
            c = randint_nullable(nrows),
            d = randint_nullable(nrows)
        )
    end
    buffer = IOBuffer()
    Arrow.write(buffer, stream)
    return HTTP.Response(200, take!(buffer))
end

println("Serving on localhost:8008...")
server = HTTP.serve(get_stream, "127.0.0.1", 8008)