Merge pull request #9814 from supabase/add-read-from-storage-example

fix: add an example for reading a file from storage

examples/edge-functions/supabase/functions/read-storage/index.ts

@@ -0,0 +1,58 @@
+// Follow this setup guide to integrate the Deno language server with your editor:
+// https://deno.land/manual/getting_started/setup_your_environment
+// This enables autocomplete, go to definition, etc.
+
+import { serve } from "https://deno.land/std@0.131.0/http/server.ts"
+import { createClient } from 'https://esm.sh/@supabase/supabase-js@2.0.0'
+
+const corsHeaders = {
+  'Access-Control-Allow-Origin': '*',
+  'Access-Control-Allow-Headers': 'authorization, x-client-info, apikey',
+}
+
+serve(async (req) => {
+  // read a text file from storage and print its contents
+  // This is needed if you're planning to invoke your function from a browser.
+  if (req.method === 'OPTIONS') {
+    return new Response('ok', { headers: corsHeaders })
+  }
+
+  try {
+    // Create a Supabase client with the Auth context of the logged in user.
+    const supabaseClient = createClient(
+      // Supabase API URL - env var exported by default.
+      Deno.env.get('SUPABASE_URL') ?? '',
+      // Supabase API ANON KEY - env var exported by default.
+      Deno.env.get('SUPABASE_ANON_KEY') ?? '',
+      // Create client with Auth context of the user that called the function.
+      // This way your row-level-security (RLS) policies are applied.
+      { global: { headers: { Authorization: req.headers.get('Authorization')! } } }
+    )
+
+    const { data, error } = await supabaseClient
+      .storage
+      .from('my-bucket')
+      .download('sample.txt')
+    if (error) throw error
+
+    // file contents are returned as a blob, we can convert it to utf-8 text by calling text() method.
+    const contents = await data.text();
+
+    // prints out the contents of the file
+    console.log(contents)
+
+    return new Response(JSON.stringify({ contents }), {
+      headers: { ...corsHeaders, 'Content-Type': 'application/json' },
+      status: 200,
+    })
+
+  } catch (error) {
+    console.error(error);
+
+    return new Response(JSON.stringify({ error: error.message }), {
+      headers: { ...corsHeaders, 'Content-Type': 'application/json' },
+      status: 400,
+    })
+  }
+
+})