Fetching metadata (-m)¶
Download only the sample metadata for an accession and skip the sequence data.
Metadata is always fetched (with or without -m) because it drives resolution; if
metadata cannot be retrieved, adaptiSeq stops before downloading. The metadata
bytes are pulled with wget, so the files are exactly what the archive serves.
SRA / ENA / DDBJ / GEO¶
adaptiSeq first queries ENA. If sample information is available it downloads
metadata in TSV format via the
ENA Portal API
(typically ~191 columns), saved as ${accession}.metadata.tsv.
If ENA has no record yet (common for very recently released SRA data), adaptiSeq falls back to the SRA Database Backend, downloading CSV (~30 columns) and converting it to TSV for consistency.
GSA¶
For GSA accessions, adaptiSeq uses GSA's getRunInfo interface to download
CSV metadata (~25 columns), saved as ${accession}.metadata.csv, and the
exportExcelFile interface for the parent Project's XLSX (sheets Sample,
Experiment, Run), saved as CRA*.metadata.xlsx.
In the Python API¶
get_metadata returns the parsed rows as a list of dicts (and writes the same
files):
from adaptiseq import get_metadata
rows = get_metadata("SRR7706354") # ENA/SRA -> list[dict] of TSV columns
rows = get_metadata("CRR311377") # GSA -> list[dict] of CSV columns
See the Python API page.
Output¶
| Database | Files |
|---|---|
| SRA / ENA / DDBJ / GEO | ${accession}.metadata.tsv |
| GSA | ${accession}.metadata.csv, CRA*.metadata.xlsx |
Note NCBI E-utilities is rate-limited to 3 req/s without a key and 10 req/s with one. Set
NCBI_API_KEY(and optionallyNCBI_EMAIL) in the environment to use the higher limit when resolving large batches.