add basic support for blossom uploads

.gitignore

@@ -193,3 +193,6 @@ tests/pagerank/network_graph_99bb5591c9116600f845107d31f9b59e2f7c7e09a1ff802e84f
 tests/test_data/wallet_mint_api/wallet.sqlite3
 .env_bkp2
 /ui/noogle/dev-dist
+tests/cat4.png
+tests/cat4.png
+*.png

nostr_dvm/utils/blossom_utils.py

@@ -0,0 +1,90 @@
+import base64
+import hashlib
+import json
+import mimetypes
+import os
+
+import aiohttp
+from nostr_sdk import Keys, Tag, EventBuilder, Kind, Timestamp
+
+
+def sha256(file):
+        h = hashlib.sha256()
+        h.update(file)
+        return h.digest().hex()
+
+async def check(url, sha256, key):
+    async with aiohttp.ClientSession(url) as sess:
+        b64_auth = await generate_blossom_header(key, sha256, "get")
+        headers = {
+            "Authorization": b64_auth
+        }
+
+        async with sess.get(f"{sha256}",   headers=headers) as resp:
+            return resp.status == 200
+
+
+async def generate_blossom_header(key, hash, method):
+
+    keys = Keys.parse(key)
+    t_tag = Tag.parse(["t", method])
+    x_tag = Tag.parse(["x", hash])
+    expiration_tag = Tag.parse(["expiration", str(Timestamp.now().as_secs() + 300)])
+    tags = [x_tag, t_tag, expiration_tag]
+
+    eb = EventBuilder(Kind(24242), "Uploading blob with SHA-256 hash").tags(tags)
+    event  = eb.sign_with_keys(keys)
+
+    encoded_nip98_event = base64.b64encode(event.as_json().encode('utf-8')).decode('utf-8')
+    return "Nostr " + encoded_nip98_event
+
+
+def upload_image_to_blossom(file_path, url):
+    """Uploads an image to a Blossom server via a PUT request."""
+
+
+async def upload_blossom(filepath, pkey, url):
+
+    with open(filepath, "rb") as f:
+        mtime = int(os.fstat(f.fileno()).st_mtime)
+
+        file = f.read()
+        hash = sha256(file)
+        b64_auth = await generate_blossom_header(pkey, hash, "upload")
+
+        file_stats = os.stat(filepath)
+        sizeinmb = file_stats.st_size / (1024 * 1024)
+        print("Filesize of Uploaded media: " + str(sizeinmb) + " Mb.")
+
+        if await check(url, hash, pkey):
+            print(f"Blob {hash} is up to date for [{filepath}].")
+        else:
+            print(f"Storing file [{hash}] on blossom.")
+
+
+            content_type = mimetypes.guess_type(filepath)[0] or 'application/octet-stream'
+
+            # Upload object to blossom.
+            async with aiohttp.ClientSession() as sess:
+                async with sess.put(
+                        url = url.rstrip('/') + '/upload',
+                        data=file,
+                        headers={
+                            "Authorization": b64_auth,
+                            "Content-Type": content_type
+                        }) as resp:
+
+
+                    if resp.status == 413:
+                        print("Can't upload on Blossom Server")
+                        return "Can't upload on Blossom Server"
+
+                    elif resp.status != 200:
+                        txt = await resp.text()
+                        print(txt)
+                    else:
+                        res = await resp.text()
+                        resjson = json.loads(res)
+                        print(resjson["url"])
+                        return resjson["url"]
+