feat(api): add typed client interface (#556)

4 files changed, 60 insertions, 6 deletions

diff --git a/lua/mason-core/managers/github/client.lua b/lua/mason-core/managers/github/client.lua
index 9583ab6d..3ef307c1 100644
--- a/lua/mason-core/managers/github/client.lua
+++ b/lua/mason-core/managers/github/client.lua
@@ -66,8 +66,7 @@ end
 ---@return Result # Result<GitHubRelease>
 function M.fetch_latest_release(repo, opts)
     opts = opts or { include_prerelease = false }
-    local path = ("/api/repo/%s/releases/latest"):format(repo)
-    return api.get(path, {
+    return api.repo.releases.latest({ repo = repo }, {
         params = {
             include_prerelease = opts.include_prerelease and "true" or "false",
         },
@@ -88,8 +87,7 @@ end
 ---@param repo string The GitHub repo ("username/repo").
 ---@return Result # Result<string> The latest tag name.
 function M.fetch_latest_tag(repo)
-    local path = ("/api/repo/%s/tags/latest"):format(repo)
-    return api.get(path):map(_.prop "tag")
+    return api.repo.tags.latest({ repo = repo }):map(_.prop "tag")
 end
 
 ---@async
diff --git a/lua/mason-core/managers/npm/init.lua b/lua/mason-core/managers/npm/init.lua
index 9cfa2be7..61ee4042 100644
--- a/lua/mason-core/managers/npm/init.lua
+++ b/lua/mason-core/managers/npm/init.lua
@@ -112,7 +112,7 @@ function M.check_outdated_primary_package(receipt, install_dir)
     local primary_package = receipt.primary_source.package
     return M.get_installed_primary_package_version(receipt, install_dir)
         :and_then(function(installed_version)
-            return api.get(("/api/npm/%s/versions/latest"):format(primary_package)):map(function(response)
+            return api.npm.versions.latest({ package = primary_package }):map(function(response)
                 return {
                     installed = installed_version,
                     latest = response.version,
diff --git a/lua/mason-registry/api.lua b/lua/mason-registry/api.lua
index 037d7fd6..b700ba47 100644
--- a/lua/mason-registry/api.lua
+++ b/lua/mason-registry/api.lua
@@ -8,9 +8,11 @@ local BASE_URL = "https://api.mason-registry.dev"
 
 local stringify_params = _.compose(_.join "&", _.map(_.join "="), _.sort_by(_.head), _.to_pairs)
 
+---@alias ApiFetchOpts { params: table<string, any>? }
+
 ---@async
 ---@param path string
----@param opts { params: table<string, any>? }?
+---@param opts ApiFetchOpts?
 ---@return Result # JSON decoded response.
 function api.get(path, opts)
     if opts and opts.params then
@@ -24,4 +26,47 @@ function api.get(path, opts)
     }):map_catching(vim.json.decode)
 end
 
+---@alias ApiSignature<T> fun(path_params: T, opts?: ApiFetchOpts): Result
+
+---@param path_template string
+local function get(path_template)
+    ---@param path_params table
+    ---@param opts ApiFetchOpts?
+    return function(path_params, opts)
+        local path = path_template:gsub("{([%w_%.0-9]+)}", function(prop)
+            return path_params[prop]
+        end)
+        -- This is done so that test stubs trigger as expected (you have to explicitly match against nil arguments)
+        if opts then
+            return api.get(path, opts)
+        else
+            return api.get(path)
+        end
+    end
+end
+
+api.repo = {
+    releases = {
+        ---@type ApiSignature<{ repo: string }>
+        latest = get "/api/repo/{repo}/releases/latest",
+        ---@type ApiSignature<{ repo: string }>
+        all = get "/api/repo/{repo}/releases/all",
+    },
+    tags = {
+        ---@type ApiSignature<{ repo: string }>
+        latest = get "/api/repo/{repo}/tags/latest",
+        ---@type ApiSignature<{ repo: string }>
+        all = get "/api/repo/{repo}/tags/all",
+    },
+}
+
+api.npm = {
+    versions = {
+        ---@type ApiSignature<{ package: string }>
+        latest = get "/api/npm/{package}/versions/latest",
+        ---@type ApiSignature<{ package: string }>
+        all = get "/api/npm/{package}/versions/all",
+    },
+}
+
 return api
diff --git a/tests/mason-registry/api_spec.lua b/tests/mason-registry/api_spec.lua
index f7b1bf45..0027e695 100644
--- a/tests/mason-registry/api_spec.lua
+++ b/tests/mason-registry/api_spec.lua
@@ -1,4 +1,5 @@
 local stub = require "luassert.stub"
+local match = require "luassert.match"
 local Result = require "mason-core.result"
 
 describe("mason-registry API", function()
@@ -38,4 +39,14 @@ describe("mason-registry API", function()
 
         assert.same({ field = { "value" } }, result)
     end)
+
+    it("should interpolate path parameters", function()
+        fetch.returns(Result.success [[{}]])
+
+        local result = api.repo.releases.latest { repo = "myrepo/name" }
+
+        assert.is_true(result:is_success())
+        assert.spy(fetch).was_called(1)
+        assert.spy(fetch).was_called_with(match.is_match "/api/repo/myrepo/name/releases/latest$", match.is_table())
+    end)
 end)