tencentcloud-cos

# Tencent Cloud COS (Object Storage) Manage Tencent Cloud COS buckets and objects via the official `cos-python-sdk-v5` client. > **Setup:** See [tencentcloud authentication](../_shared/tencentcloud.md) for SecretId / SecretKey / region setup. The SDK reads `TENCENTCLOUD_SECRET_ID` / `TENCENTCLOUD_SECRET_KEY` / `TENCENTCLOUD_REGION` from the environment. ## CLI (preferred) The skill ships [`scripts/cos.py`](scripts/cos.py) — a self-contained CLI that wraps every COS operation below. **Prefer this over hand-rolled SDK calls** when the user's request maps cleanly onto one of its subcommands; it's what the maintained code paths exercise. ```bash # $SKILL_DIR can point at another skill loaded this turn — anchor on our own # script (re-run this at the top of every fresh-shell Bash block). COS="$SKILL_DIR/scripts/cos.py"; [ -f "$COS" ] || COS=$(find /tmp -maxdepth 8 -path '*/skills/*/scripts/cos.py' 2>/dev/null | head -1) [ -f "$COS" ] || { echo "tencentcloud-cos script not found (SKILL_DIR=$SKILL_DIR)" >&2; exit 1; } python3 $COS buckets # list all buckets python3 $COS ls mydata-1250000000 --prefix images/ # list objects python3 $COS upload mydata-1250000000 ./report.pdf --key docs/report-2026.pdf python3 $COS download mydata-1250000000 docs/report-2026.pdf --output ./out.pdf python3 $COS url mydata-1250000000 docs/report-2026.pdf --expires 3600 python3 $COS du mydata-1250000000 --prefix logs/ python3 $COS cp mydata-1250000000 old/path.txt new/path.txt python3 $COS batch-delete mydata-1250000000 --prefix temp/old/ --dry-run python3 $COS batch-delete mydata-1250000000 --prefix temp/old/ # actually delete python3 $COS info mydata-1250000000 docs/report-2026.pdf ``` Run `python3 $COS --help` (or `python3 $COS <cmd> --help`) for full flags. Pass `--region <region>` to override per-call. ## When to Use - List COS buckets across the account - List objects in a bucket (with prefix / delimiter filtering) - Upload / download files - Delete a single object or batch-delete by prefix - Generate pre-signed download URLs (private bucket sharing) - Calculate bucket / prefix storage usage - Copy objects within a bucket ## Dependencies ```bash pip install cos-python-sdk-v5 ``` ## Bucket naming Tencent Cloud bucket names always end in `-<APPID>`, e.g. `mydata-1250000000`. The APPID is the numeric account identifier. The SDK requires the full `name-APPID` form everywhere a bucket is named. ## Quick start ```python import os from qcloud_cos import CosConfig, CosS3Client config = CosConfig( Region=os.environ["TENCENTCLOUD_REGION"], SecretId=os.environ["TENCENTCLOUD_SECRET_ID"], SecretKey=os.environ["TENCENTCLOUD_SECRET_KEY"], Scheme="https", ) client = CosS3Client(config) ``` ## Workflows ### List all buckets ```python resp = client.list_buckets() for b in resp["Buckets"]["Bucket"]: print(b["Name"], b["Location"], b["CreationDate"]) ``` ### List objects in a bucket ```python # Single page (max 1000 objects) resp = client.list_objects(Bucket="mydata-1250000000", Prefix="images/", Delimiter="/") for obj in resp.get("Contents", []): print(obj["Key"], int(obj["Size"]), obj["LastModified"]) # Paginate through everything marker = "" while True: resp = client.list_objects(Bucket="mydata-1250000000", Prefix="logs/", Marker=marker, MaxKeys=1000) for obj in resp.get("Contents", []): print(obj["Key"]) if resp.get("IsTruncated") != "true": break marker = resp["NextMarker"] ``` ### Upload a file ```python # Streaming upload — handles multipart / resumes / 5GB+ files transparently client.upload_file( Bucket="mydata-1250000000", Key="uploads/2026/report.pdf", LocalFilePath="./report.pdf", ) ``` ### Download a file ```python client.download_file( Bucket="mydata-1250000000", Key="uploads/2026/report.pdf", DestFilePath="./report.pdf", ) ``` ### Generate a pre-signed download URL ```python # Default expiry 1 hour; pass Expired=86400 for 24h, etc. url = client.get_presigned_url( Method="GET", Bucket="mydata-1250000000", Key="uploads/2026/report.pdf", Expired=3600, ) print(url) ``` ### Delete a single object ```python client.delete_object(Bucket="mydata-1250000000", Key="uploads/old-file.txt") ``` ### Batch delete by prefix (with dry-run safety) ```python # 1) Always preview first to_delete = [] marker = "" while True: resp = client.list_objects(Bucket="mydata-1250000000", Prefix="temp/old/", Marker=marker, MaxKeys=1000) for obj in resp.get("Contents", []): to_delete.append({"Key": obj["Key"]}) if resp.get("IsTruncated") != "true": break marker = resp["NextMarker"] print(f"Would delete {len(to_delete)} objects") for o in to_delete[:10]: print(" -", o["Key"]) # 2) Confirm with the user before running this: # resp = client.delete_objects(Bucket="mydata-1250000000", Delete={"Object": to_delete, "Quiet": "false"}) # print("Deleted:", len(resp.get("Deleted", []))) ``` ### Calculate bucket / prefix size (du) ```python total_bytes = 0 total_count = 0 marker = "" while True: resp = client.list_objects(Bucket="mydata-1250000000", Prefix="logs/", Marker=marker, MaxKeys=1000) for obj in resp.get("Contents", []): total_bytes += int(obj["Size"]) total_count += 1 if resp.get("IsTruncated") != "true": break marker = resp["NextMarker"] print(f"{total_count} objects, {total_bytes / 1024 / 1024:.1f} MiB") ``` ### Copy objects within a bucket ```python client.copy_object( Bucket="mydata-1250000000", Key="new/path.txt", CopySource={ "Bucket": "mydata-1250000000", "Key": "old/path.txt", "Region": os.environ["TENCENTCLOUD_REGION"], }, ) ``` ## Safety reminders - **Confirm batch deletes with the user** before running. The `delete_objects` call is irreversible — there's no recycle bin in COS by default. - **Pre-signed URLs are bearer tokens** — anyone with the URL gets the object until it expires. Default to short expiries (1 hour) unless the user explicitly asks for longer. - **Cross-region operations** require the source / destination Region in `CopySource`. Mismatched region triggers `NoSuchBucket`. - **`download_file` overwrites the destination** without asking. Pick `DestFilePath` carefully when scripting in a loop. ## Error patterns | Symptom | Likely cause | |---|---| | `NoSuchBucket` | Wrong region, wrong APPID suffix on the bucket name | | `AccessDenied` | Sub-account missing `QcloudCOSReadOnlyAccess` / `QcloudCOSDataReadOnly` etc. | | `SignatureDoesNotMatch` | SecretKey was pasted with leading / trailing whitespace, or the system clock is off by more than 5 minutes | | `RequestTimeTooSkewed` | Same — clock skew | ## Console links - COS console: <https://console.cloud.tencent.com/cos/bucket> - API reference: <https://www.tencentcloud.com/document/product/436/41330>