I am using metadata heavily with my Google Cloud Storage Bucket, now i have a use case where i need to search the files using some of the metadata field values. I have looked at the entire documentation (https://cloud.google.com/storage/docs/gsutil/addlhelp/WorkingWithObjectMetadata) but i didn't find anything related to search on Metadata, is there any why i can do this or should i go ahead and build something myself?
2 Answers
2
votes
It is possible now to do so with APIs.
Set up CUSTOM metadata:
- Visit Viewing and Editing Object Metadata documentation, for more information.
- Use
gsutil setmeta -h "[METADATA_KEY]:[METADATA_VALUE]" gs://[BUCKET_NAME]/[OBJECT_NAME]command. - [METADATA_KEY] should start with
x-goog-meta-as stated in the documentation for custom metadata. So [METADATA_KEY] =x-goog-meta-[CUSTOM_VALUE]. NOTE no spaces in the value. - [METADATA_VALUE] should also be without spaces. Use
_or-.
Search objects based on CUSTOM metadata of objects using APIs.
This example is for Python, but there are a lot of other languages supported in the Listing Objects documentation.
- List the objects in the bucket Sample Code
- For every object found, list all the metadata. Sample Code
- Instead of printing them, take the
blob.metadatapart only and convert it to string. If it is a default value it will beNoneotherwise it will be your set up custom metadata key in JSON format. - Use the value to perform a
==operation to check if it is compatible with the value you are looking for and perform any actions accordingly. - NOTE: The custom values are saved without the
x-goog-meta-prefix. It is used only to determine for the API call when setting metadata that this value is custom. Only the second part will be visible in metadata. e.g. you usex-goog-meta-test_metadatait will be visible astest_metadata.
I have did a little bit of coding myself and this is a Python example doing exactly what I described above. You can find the code in GitHub here.
