# Sitemapper
[](https://hex.pm/packages/sitemapper)
Sitemapper is an Elixir library for generating [XML Sitemaps](https://www.sitemaps.org).
It's designed to generate large sitemaps while maintaining a low memory profile. It can persist sitemaps to Amazon S3, GCP Storage, disk or any other adapter you wish to write.
## Installation
```elixir
def deps do
[
{:sitemapper, "~> 0.8"}
]
end
```
## Usage
```elixir
def generate_sitemap() do
config = [
store: Sitemapper.S3Store,
store_config: [bucket: "example-bucket"],
sitemap_url: "http://example-bucket.s3-aws-region.amazonaws.com"
]
Stream.concat([1..100_001])
|> Stream.map(fn i ->
%Sitemapper.URL{
loc: "http://example.com/page-#{i}",
changefreq: :daily,
lastmod: Date.utc_today()
}
end)
|> Sitemapper.generate(config)
|> Sitemapper.persist(config)
|> Stream.run()
end
```
`Sitemapper.generate` receives a `Stream` of URLs. This makes it easy to stream the contents of an Ecto Repo into a sitemap.
```elixir
def generate_sitemap() do
config = [
store: Sitemapper.S3Store,
store_config: [bucket: "example-bucket"],
sitemap_url: "http://example-bucket.s3-aws-region.amazonaws.com"
]
Repo.transaction(fn ->
User
|> Repo.stream()
|> Stream.map(fn %User{username: username, updated_at: updated_at} ->
%Sitemapper.URL{
loc: "http://example.com/users/#{username}",
changefreq: :hourly,
lastmod: updated_at
}
end)
|> Sitemapper.generate(config)
|> Sitemapper.persist(config)
|> Stream.run()
end)
end
```
To persist your sitemaps to the local file system, instead of Amazon S3, your config should look like:
```elixir
[
store: Sitemapper.FileStore,
store_config: [
path: sitemap_folder_path
],
sitemap_url: "http://yourdomain.com"
]
```
Note that you'll need to finish on `Stream.run/1` or `Enum.to_list/1` to execute the stream and return the result.
## Todo
- Support extended Sitemap properties, like images, video, etc.
## Benchmarks
`sitemapper` is about 50% faster than `fast_sitemap`. In the large scenario below (1,000,000 URLs) `sitemapper` uses ~50MB peak memory consumption, while `fast_sitemap` uses ~1000MB.
```shell
$ MIX_ENV=bench mix run bench/bench.exs
Operating System: macOS
CPU Information: Intel(R) Core(TM) i7-4870HQ CPU @ 2.50GHz
Number of Available Cores: 8
Available memory: 16 GB
Elixir 1.9.1
Erlang 22.0.4
Benchmark suite executing with the following configuration:
warmup: 2 s
time: 10 s
memory time: 0 ns
parallel: 1
inputs: large, medium, small
Estimated total run time: 1.20 min
Benchmarking fast_sitemap - simple with input large...
Benchmarking fast_sitemap - simple with input medium...
Benchmarking fast_sitemap - simple with input small...
Benchmarking sitemapper - simple with input large...
Benchmarking sitemapper - simple with input medium...
Benchmarking sitemapper - simple with input small...
##### With input large #####
Name ips average deviation median 99th %
sitemapper - simple 0.0353 28.32 s ±0.00% 28.32 s 28.32 s
fast_sitemap - simple 0.0223 44.76 s ±0.00% 44.76 s 44.76 s
Comparison:
sitemapper - simple 0.0353
fast_sitemap - simple 0.0223 - 1.58x slower +16.45 s
##### With input medium #####
Name ips average deviation median 99th %
sitemapper - simple 0.35 2.85 s ±0.57% 2.85 s 2.87 s
fast_sitemap - simple 0.23 4.28 s ±0.46% 4.28 s 4.30 s
Comparison:
sitemapper - simple 0.35
fast_sitemap - simple 0.23 - 1.50x slower +1.43 s
##### With input small #####
Name ips average deviation median 99th %
sitemapper - simple 32.00 31.25 ms ±8.01% 31.20 ms 37.22 ms
fast_sitemap - simple 21.55 46.41 ms ±6.96% 46.26 ms 56.36 ms
Comparison:
sitemapper - simple 32.00
fast_sitemap - simple 21.55 - 1.49x slower +15.16 ms
```
