Changelog

v0.9.0 (2026-08-12)

Breaking Changes

• Require Elixir 1.15 or later
• Unknown options now raise an ArgumentError instead of being silently ignored, both in SRTM.get_elevation/3 and in the built-in sources
• Report a failed or unexpected archive as :invalid_archive instead of :io_error

Added

• Make SRTM.DataCell.new/2 and SRTM.DataCell.to_binary/1 public, so SRTM.Cache implementations can parse and serialize cached HGT files
• Make SRTM.Source.get/2 public and document its :timeout option, along with the :endpoint option of SRTM.Source.AWS and SRTM.Source.ESA
• Document what a nil elevation means, how to implement a source or a cache, and where the disk cache writes the files it downloads

Changed

• Fetch the SRTMGL1 dataset in SRTM.Source.ESA over HTTPS instead of HTTP
• Store each HGT file under its own :persistent_term key, so caching a file no longer rewrites the whole cache or triggers a global garbage collection
• Pass source options through to the HTTP request, making :timeout usable via sources: [{SRTM.Source.AWS, timeout: 5_000}]
• Widen the :reason of SRTM.Error to include the tuples :httpc reports, such as {:failed_connect, _}

Fixed

• Disabling both caches no longer returns a :missing_caches error; every lookup downloads the HGT file instead
• Return :error instead of raising when an HGT file in the disk cache can't be read
• Return an error instead of raising when a downloaded file isn't a readable archive, so the next source gets a turn
• Point the source links in the published documentation at the tagged revision, which used to 404

v0.8.0 (2023-08-14)

Breaking Changes

• Remove SRTM.Client
• Remove SRTM.Client.purge_in_memory_cache/2
• Add in-memory cache backend by :persistent_term
• Add :disk_cache_enabled, :disk_cache_path, :in_memory_cache_enabled and :in_memory_cache_module options to SRTM.get_elevation/3

v0.7.0 (2023-08-13)

Breaking Changes

• Require Elixir 1.11
• Remove USGS source
• Drop :adapter and :opts option from SRTM.Client.new/1

Changes

• Replace hackney with httpc
• Update documentation
• Add CI workflow

v0.6.0 (2020-12-02)

Breaking Changes

• Use Tesla.Adapter.Hackney as default adapter. Add hackney to the list of dependencies if you don't want to use another HTTP adapter (see Tesla Adapters to find all available adapters and SRTM.Client.new/2 on how to configure another adapter).

  def deps do
    [
      {:srtm, "~> 0.6"},
      {:hackney, "~> 1.15"}
    ]
  end