1 files changed, 102 insertions, 0 deletions
diff --git a/app_expo/services/api/api.ts b/app_expo/services/api/api.ts
new file mode 100644
index 0000000..4093d34
--- /dev/null
+++ b/app_expo/services/api/api.ts
@@ -0,0 +1,102 @@
+import { ApisauceInstance, create, ApiResponse } from 'apisauce'
+import { getGeneralApiProblem } from './api-problem'
+import { ApiConfig, DEFAULT_API_CONFIG } from './api-config'
+import * as Types from './api.types'
+
+/**
+ * Manages all requests to the API.
+ */
+export class Api {
+  /**
+   * The underlying apisauce instance which performs the requests.
+   */
+  apisauce: ApisauceInstance
+
+  /**
+   * Configurable options.
+   */
+  config: ApiConfig
+
+  /**
+   * Creates the api.
+   *
+   * @param config The configuration to use.
+   */
+  constructor(config: ApiConfig = DEFAULT_API_CONFIG) {
+    this.config = config
+  }
+
+  /**
+   * Sets up the API.  This will be called during the bootup
+   * sequence and will happen before the first React component
+   * is mounted.
+   *
+   * Be as quick as possible in here.
+   */
+  setup() {
+    // construct the apisauce instance
+    this.apisauce = create({
+      baseURL: this.config.url,
+      timeout: this.config.timeout,
+      headers: {
+        Accept: 'application/json',
+      },
+    })
+  }
+
+  /**
+   * Gets a list of users.
+   */
+  async getUsers(): Promise<Types.GetUsersResult> {
+    // make the api call
+    const response: ApiResponse<any> = await this.apisauce.get(`/users`)
+
+    // the typical ways to die when calling an api
+    if (!response.ok) {
+      const problem = getGeneralApiProblem(response)
+      if (problem) return problem
+    }
+
+    const convertUser = (raw) => {
+      return {
+        id: raw.id,
+        name: raw.name,
+      }
+    }
+
+    // transform the data into the format we are expecting
+    try {
+      const rawUsers = response.data
+      const resultUsers: Types.User[] = rawUsers.map(convertUser)
+      return { kind: 'ok', users: resultUsers }
+    } catch {
+      return { kind: 'bad-data' }
+    }
+  }
+
+  /**
+   * Gets a single user by ID
+   */
+
+  async getUser(id: string): Promise<Types.GetUserResult> {
+    // make the api call
+    const response: ApiResponse<any> = await this.apisauce.get(`/users/${id}`)
+
+    // the typical ways to die when calling an api
+    if (!response.ok) {
+      const problem = getGeneralApiProblem(response)
+      if (problem) return problem
+    }
+
+    // transform the data into the format we are expecting
+    try {
+      const resultUser: Types.User = {
+        id: response.data.id,
+        name: response.data.name,
+      }
+      return { kind: 'ok', user: resultUser }
+    } catch {
+      return { kind: 'bad-data' }
+    }
+  }
+}